NEWS
author wenzelm
Fri Sep 24 16:17:59 2010 +0200 (2010-09-24)
changeset 39689 78b185bf7660
parent 39644 ad436fa9fc5b
child 39754 150f831ce4a3
permissions -rw-r--r--
clarified @{type} antiquotation: abbreviations and nonterminals count as "syntactic", disallow TFrees;
tuned;
     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 * Improved infrastructure for term evaluation using code generator
    78 techniques, in particular static evaluation conversions.
    79 
    80 * String.literal is a type, but not a datatype. INCOMPATIBILITY.
    81  
    82 * Renamed lemmas:
    83   expand_fun_eq -> fun_eq_iff
    84   expand_set_eq -> set_eq_iff
    85   set_ext -> set_eqI
    86  INCOMPATIBILITY.
    87 
    88 * Renamed class eq and constant eq (for code generation) to class equal
    89 and constant equal, plus renaming of related facts and various tuning.
    90 INCOMPATIBILITY.
    91 
    92 * Scala (2.8 or higher) has been added to the target languages of
    93 the code generator.
    94 
    95 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
    96 
    97 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    98 canonical names for instance definitions for functions; various improvements.
    99 INCOMPATIBILITY.
   100 
   101 * Records: logical foundation type for records do not carry a '_type' suffix
   102 any longer.  INCOMPATIBILITY.
   103 
   104 * Code generation for records: more idiomatic representation of record types.
   105 Warning: records are not covered by ancient SML code generation any longer.
   106 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
   107 helps to succeed then:
   108 
   109   record 'a foo = ...
   110   ...
   111   rep_datatype foo_ext ...
   112 
   113 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   114 INCOMPATIBILITY.
   115 
   116 * Quickcheck in locales considers interpretations of that locale for
   117 counter example search.
   118 
   119 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   120 in Library/State_Monad has been changed to avoid ambiguities.
   121 INCOMPATIBILITY.
   122 
   123 * Code generator: export_code without explicit file declaration prints
   124 to standard output.  INCOMPATIBILITY.
   125 
   126 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   127 respectively.  INCOMPATIBILITY.
   128 
   129 * Constant "split" has been merged with constant "prod_case";  names
   130 of ML functions, facts etc. involving split have been retained so far,
   131 though.  INCOMPATIBILITY.
   132 
   133 * Dropped old infix syntax "mem" for List.member;  use "in set"
   134 instead.  INCOMPATIBILITY.
   135 
   136 * Refactoring of code-generation specific operations in List.thy
   137 
   138   constants
   139     null ~> List.null
   140 
   141   facts
   142     mem_iff ~> member_def
   143     null_empty ~> null_def
   144 
   145 INCOMPATIBILITY.  Note that these were not suppossed to be used
   146 regularly unless for striking reasons;  their main purpose was code
   147 generation.
   148 
   149 * Some previously unqualified names have been qualified:
   150 
   151   types
   152     bool ~> HOL.bool
   153     nat ~> Nat.nat
   154 
   155   constants
   156     Trueprop ~> HOL.Trueprop
   157     True ~> HOL.True
   158     False ~> HOL.False
   159     op & ~> HOL.conj
   160     op | ~> HOL.disj
   161     op --> ~> HOL.implies
   162     op = ~> HOL.eq
   163     Not ~> HOL.Not
   164     The ~> HOL.The
   165     All ~> HOL.All
   166     Ex ~> HOL.Ex
   167     Ex1 ~> HOL.Ex1
   168     Let ~> HOL.Let
   169     If ~> HOL.If
   170     Ball ~> Set.Ball
   171     Bex ~> Set.Bex
   172     Suc ~> Nat.Suc
   173     Pair ~> Product_Type.Pair
   174     fst ~> Product_Type.fst
   175     snd ~> Product_Type.snd
   176     curry ~> Product_Type.curry
   177     op : ~> Set.member
   178     Collect ~> Set.Collect
   179 
   180 INCOMPATIBILITY.
   181 
   182 * Removed simplifier congruence rule of "prod_case", as has for long
   183 been the case with "split".  INCOMPATIBILITY.
   184 
   185 * Datatype package: theorems generated for executable equality
   186 (class eq) carry proper names and are treated as default code
   187 equations.
   188 
   189 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   190 INCOMPATIBILITY.
   191 
   192 * List.thy: use various operations from the Haskell prelude when
   193 generating Haskell code.
   194 
   195 * Multiset.thy: renamed empty_idemp -> empty_neutral
   196 
   197 * code_simp.ML and method code_simp: simplification with rules determined
   198 by code generator.
   199 
   200 * code generator: do not print function definitions for case
   201 combinators any longer.
   202 
   203 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   204 theorems are now stated in terms of euclidean spaces instead of finite
   205 cartesian products.
   206 
   207   types
   208     real ^ 'n ~>  'a::real_vector
   209               ~>  'a::euclidean_space
   210               ~>  'a::ordered_euclidean_space
   211         (depends on your needs)
   212 
   213   constants
   214      _ $ _        ~> _ $$ _
   215      \<chi> x. _  ~> \<chi>\<chi> x. _
   216      CARD('n)     ~> DIM('a)
   217 
   218 Also note that the indices are now natural numbers and not from some finite
   219 type. Finite cartesian products of euclidean spaces, products of euclidean
   220 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   221 
   222 INCOMPATIBILITY.
   223 
   224 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   225 as value for measures. Introduces Lebesgue Measure based on the integral in
   226 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   227 spaces.
   228 
   229  INCOMPATIBILITY.
   230 
   231 * Inductive package: offers new command "inductive_simps" to automatically
   232 derive instantiated and simplified equations for inductive predicates,
   233 similar to inductive_cases.
   234 
   235 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   236 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   237 The theorems bij_def and surj_def are unchanged.
   238 
   239 *** FOL ***
   240 
   241 * All constant names are now qualified.  INCOMPATIBILITY.
   242 
   243 
   244 *** ZF ***
   245 
   246 * All constant names are now qualified.  INCOMPATIBILITY.
   247 
   248 
   249 *** ML ***
   250 
   251 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   252 meaning.
   253 
   254 * Renamed structure PureThy to Pure_Thy and moved most of its
   255 operations to structure Global_Theory, to emphasize that this is
   256 rarely-used global-only stuff.
   257 
   258 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   259 instead (or tracing for high-volume output).
   260 
   261 * Configuration option show_question_marks only affects regular pretty
   262 printing of types and terms, not raw Term.string_of_vname.
   263 
   264 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   265 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   266 @{thms} for most purposes.
   267 
   268 * ML structure Unsynchronized never opened, not even in Isar
   269 interaction mode as before.  Old Unsynchronized.set etc. have been
   270 discontinued -- use plain := instead.  This should be *rare* anyway,
   271 since modern tools always work via official context data, notably
   272 configuration options.
   273 
   274 * ML antiquotations @{theory} and @{theory_ref} refer to named
   275 theories from the ancestry of the current context, not any accidental
   276 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   277 change in semantics.
   278 
   279 * Parallel and asynchronous execution requires special care concerning
   280 interrupts.  Structure Exn provides some convenience functions that
   281 avoid working directly with raw Interrupt.  User code must not absorb
   282 interrupts -- intermediate handling (for cleanup etc.) needs to be
   283 followed by re-raising of the original exception.  Another common
   284 source of mistakes are "handle _" patterns, which make the meaning of
   285 the program subject to physical effects of the environment.
   286 
   287 
   288 *** System ***
   289 
   290 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   291 
   292 
   293 
   294 New in Isabelle2009-2 (June 2010)
   295 ---------------------------------
   296 
   297 *** General ***
   298 
   299 * Authentic syntax for *all* logical entities (type classes, type
   300 constructors, term constants): provides simple and robust
   301 correspondence between formal entities and concrete syntax.  Within
   302 the parse tree / AST representations, "constants" are decorated by
   303 their category (class, type, const) and spelled out explicitly with
   304 their full internal name.
   305 
   306 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   307 and translations (translation rules and translation functions in ML).
   308 Some hints on upgrading:
   309 
   310   - Many existing uses of 'syntax' and 'translations' can be replaced
   311     by more modern 'type_notation', 'notation' and 'abbreviation',
   312     which are independent of this issue.
   313 
   314   - 'translations' require markup within the AST; the term syntax
   315     provides the following special forms:
   316 
   317       CONST c   -- produces syntax version of constant c from context
   318       XCONST c  -- literally c, checked as constant from context
   319       c         -- literally c, if declared by 'syntax'
   320 
   321     Plain identifiers are treated as AST variables -- occasionally the
   322     system indicates accidental variables via the error "rhs contains
   323     extra variables".
   324 
   325     Type classes and type constructors are marked according to their
   326     concrete syntax.  Some old translations rules need to be written
   327     for the "type" category, using type constructor application
   328     instead of pseudo-term application of the default category
   329     "logic".
   330 
   331   - 'parse_translation' etc. in ML may use the following
   332     antiquotations:
   333 
   334       @{class_syntax c}   -- type class c within parse tree / AST
   335       @{term_syntax c}    -- type constructor c within parse tree / AST
   336       @{const_syntax c}   -- ML version of "CONST c" above
   337       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   338 
   339   - Literal types within 'typed_print_translations', i.e. those *not*
   340     represented as pseudo-terms are represented verbatim.  Use @{class
   341     c} or @{type_name c} here instead of the above syntax
   342     antiquotations.
   343 
   344 Note that old non-authentic syntax was based on unqualified base
   345 names, so all of the above "constant" names would coincide.  Recall
   346 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   347 diagnose syntax problems.
   348 
   349 * Type constructors admit general mixfix syntax, not just infix.
   350 
   351 * Concrete syntax may be attached to local entities without a proof
   352 body, too.  This works via regular mixfix annotations for 'fix',
   353 'def', 'obtain' etc. or via the explicit 'write' command, which is
   354 similar to the 'notation' command in theory specifications.
   355 
   356 * Discontinued unnamed infix syntax (legacy feature for many years) --
   357 need to specify constant name and syntax separately.  Internal ML
   358 datatype constructors have been renamed from InfixName to Infix etc.
   359 Minor INCOMPATIBILITY.
   360 
   361 * Schematic theorem statements need to be explicitly markup as such,
   362 via commands 'schematic_lemma', 'schematic_theorem',
   363 'schematic_corollary'.  Thus the relevance of the proof is made
   364 syntactically clear, which impacts performance in a parallel or
   365 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   366 
   367 * Use of cumulative prems via "!" in some proof methods has been
   368 discontinued (old legacy feature).
   369 
   370 * References 'trace_simp' and 'debug_simp' have been replaced by
   371 configuration options stored in the context. Enabling tracing (the
   372 case of debugging is similar) in proofs works via
   373 
   374   using [[trace_simp = true]]
   375 
   376 Tracing is then active for all invocations of the simplifier in
   377 subsequent goal refinement steps. Tracing may also still be enabled or
   378 disabled via the ProofGeneral settings menu.
   379 
   380 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   381 'hide_fact' replace the former 'hide' KIND command.  Minor
   382 INCOMPATIBILITY.
   383 
   384 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   385 more efficient than combinations with -q1 or -q2.
   386 
   387 
   388 *** Pure ***
   389 
   390 * Proofterms record type-class reasoning explicitly, using the
   391 "unconstrain" operation internally.  This eliminates all sort
   392 constraints from a theorem and proof, introducing explicit
   393 OFCLASS-premises.  On the proof term level, this operation is
   394 automatically applied at theorem boundaries, such that closed proofs
   395 are always free of sort constraints.  INCOMPATIBILITY for tools that
   396 inspect proof terms.
   397 
   398 * Local theory specifications may depend on extra type variables that
   399 are not present in the result type -- arguments TYPE('a) :: 'a itself
   400 are added internally.  For example:
   401 
   402   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   403 
   404 * Predicates of locales introduced by classes carry a mandatory
   405 "class" prefix.  INCOMPATIBILITY.
   406 
   407 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   408 
   409 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   410 'class' instead.
   411 
   412 * Command 'code_reflect' allows to incorporate generated ML code into
   413 runtime environment; replaces immature code_datatype antiquotation.
   414 INCOMPATIBILITY.
   415 
   416 * Code generator: simple concept for abstract datatypes obeying
   417 invariants.
   418 
   419 * Code generator: details of internal data cache have no impact on the
   420 user space functionality any longer.
   421 
   422 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   423 subgoals.  This is more appropriate for interpretations with 'where'.
   424 INCOMPATIBILITY.
   425 
   426 * Command 'example_proof' opens an empty proof body.  This allows to
   427 experiment with Isar, without producing any persistent result.
   428 
   429 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   430 within a local theory context, with explicit checking of the
   431 constructors involved (in contrast to the raw 'syntax' versions).
   432 
   433 * Commands 'types' and 'typedecl' now work within a local theory
   434 context -- without introducing dependencies on parameters or
   435 assumptions, which is not possible in Isabelle/Pure.
   436 
   437 * Command 'defaultsort' has been renamed to 'default_sort', it works
   438 within a local theory context.  Minor INCOMPATIBILITY.
   439 
   440 
   441 *** HOL ***
   442 
   443 * Command 'typedef' now works within a local theory context -- without
   444 introducing dependencies on parameters or assumptions, which is not
   445 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   446 contain multiple interpretations of local typedefs (with different
   447 non-emptiness proofs), even in a global theory context.
   448 
   449 * New package for quotient types.  Commands 'quotient_type' and
   450 'quotient_definition' may be used for defining types and constants by
   451 quotient constructions.  An example is the type of integers created by
   452 quotienting pairs of natural numbers:
   453 
   454   fun
   455     intrel :: "(nat * nat) => (nat * nat) => bool"
   456   where
   457     "intrel (x, y) (u, v) = (x + v = u + y)"
   458 
   459   quotient_type int = "nat * nat" / intrel
   460     by (auto simp add: equivp_def expand_fun_eq)
   461 
   462   quotient_definition
   463     "0::int" is "(0::nat, 0::nat)"
   464 
   465 The method "lifting" can be used to lift of theorems from the
   466 underlying "raw" type to the quotient type.  The example
   467 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   468 construction and provides a reasoning infrastructure for finite sets.
   469 
   470 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   471 clash with new theory Quotient in Main HOL.
   472 
   473 * Moved the SMT binding into the main HOL session, eliminating
   474 separate HOL-SMT session.
   475 
   476 * List membership infix mem operation is only an input abbreviation.
   477 INCOMPATIBILITY.
   478 
   479 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   480 for future developements; former Library/Word.thy is still present in
   481 the AFP entry RSAPPS.
   482 
   483 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   484 longer shadowed.  INCOMPATIBILITY.
   485 
   486 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   487 INCOMPATIBILITY.
   488 
   489 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   490 INCOMPATIBILITY.
   491 
   492 * Dropped normalizing_semiring etc; use the facts in semiring classes
   493 instead.  INCOMPATIBILITY.
   494 
   495 * Dropped several real-specific versions of lemmas about floor and
   496 ceiling; use the generic lemmas from theory "Archimedean_Field"
   497 instead.  INCOMPATIBILITY.
   498 
   499   floor_number_of_eq         ~> floor_number_of
   500   le_floor_eq_number_of      ~> number_of_le_floor
   501   le_floor_eq_zero           ~> zero_le_floor
   502   le_floor_eq_one            ~> one_le_floor
   503   floor_less_eq_number_of    ~> floor_less_number_of
   504   floor_less_eq_zero         ~> floor_less_zero
   505   floor_less_eq_one          ~> floor_less_one
   506   less_floor_eq_number_of    ~> number_of_less_floor
   507   less_floor_eq_zero         ~> zero_less_floor
   508   less_floor_eq_one          ~> one_less_floor
   509   floor_le_eq_number_of      ~> floor_le_number_of
   510   floor_le_eq_zero           ~> floor_le_zero
   511   floor_le_eq_one            ~> floor_le_one
   512   floor_subtract_number_of   ~> floor_diff_number_of
   513   floor_subtract_one         ~> floor_diff_one
   514   ceiling_number_of_eq       ~> ceiling_number_of
   515   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   516   ceiling_le_zero_eq         ~> ceiling_le_zero
   517   ceiling_le_eq_one          ~> ceiling_le_one
   518   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   519   less_ceiling_eq_zero       ~> zero_less_ceiling
   520   less_ceiling_eq_one        ~> one_less_ceiling
   521   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   522   ceiling_less_eq_zero       ~> ceiling_less_zero
   523   ceiling_less_eq_one        ~> ceiling_less_one
   524   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   525   le_ceiling_eq_zero         ~> zero_le_ceiling
   526   le_ceiling_eq_one          ~> one_le_ceiling
   527   ceiling_subtract_number_of ~> ceiling_diff_number_of
   528   ceiling_subtract_one       ~> ceiling_diff_one
   529 
   530 * Theory "Finite_Set": various folding_XXX locales facilitate the
   531 application of the various fold combinators on finite sets.
   532 
   533 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   534 provides abstract red-black tree type which is backed by "RBT_Impl" as
   535 implementation.  INCOMPATIBILTY.
   536 
   537 * Theory Library/Coinductive_List has been removed -- superseded by
   538 AFP/thys/Coinductive.
   539 
   540 * Theory PReal, including the type "preal" and related operations, has
   541 been removed.  INCOMPATIBILITY.
   542 
   543 * Real: new development using Cauchy Sequences.
   544 
   545 * Split off theory "Big_Operators" containing setsum, setprod,
   546 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   547 
   548 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   549 "Int" etc.  INCOMPATIBILITY.
   550 
   551 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   552 
   553 * New set of rules "ac_simps" provides combined assoc / commute
   554 rewrites for all interpretations of the appropriate generic locales.
   555 
   556 * Renamed theory "OrderedGroup" to "Groups" and split theory
   557 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   558 appropriate and more consistent names suitable for name prefixes
   559 within the HOL theories.  INCOMPATIBILITY.
   560 
   561 * Some generic constants have been put to appropriate theories:
   562   - less_eq, less: Orderings
   563   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   564   - inverse, divide: Rings
   565 INCOMPATIBILITY.
   566 
   567 * More consistent naming of type classes involving orderings (and
   568 lattices):
   569 
   570     lower_semilattice                   ~> semilattice_inf
   571     upper_semilattice                   ~> semilattice_sup
   572 
   573     dense_linear_order                  ~> dense_linorder
   574 
   575     pordered_ab_group_add               ~> ordered_ab_group_add
   576     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   577     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   578     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   579     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   580     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   581     pordered_cancel_semiring            ~> ordered_cancel_semiring
   582     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   583     pordered_comm_ring                  ~> ordered_comm_ring
   584     pordered_comm_semiring              ~> ordered_comm_semiring
   585     pordered_ring                       ~> ordered_ring
   586     pordered_ring_abs                   ~> ordered_ring_abs
   587     pordered_semiring                   ~> ordered_semiring
   588 
   589     ordered_ab_group_add                ~> linordered_ab_group_add
   590     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   591     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   592     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   593     ordered_field                       ~> linordered_field
   594     ordered_field_no_lb                 ~> linordered_field_no_lb
   595     ordered_field_no_ub                 ~> linordered_field_no_ub
   596     ordered_field_dense_linear_order    ~> dense_linordered_field
   597     ordered_idom                        ~> linordered_idom
   598     ordered_ring                        ~> linordered_ring
   599     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   600     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   601     ordered_ring_strict                 ~> linordered_ring_strict
   602     ordered_semidom                     ~> linordered_semidom
   603     ordered_semiring                    ~> linordered_semiring
   604     ordered_semiring_1                  ~> linordered_semiring_1
   605     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   606     ordered_semiring_strict             ~> linordered_semiring_strict
   607 
   608   The following slightly odd type classes have been moved to a
   609   separate theory Library/Lattice_Algebras:
   610 
   611     lordered_ab_group_add               ~> lattice_ab_group_add
   612     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   613     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   614     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   615     lordered_ring                       ~> lattice_ring
   616 
   617 INCOMPATIBILITY.
   618 
   619 * Refined field classes:
   620   - classes division_ring_inverse_zero, field_inverse_zero,
   621     linordered_field_inverse_zero include rule inverse 0 = 0 --
   622     subsumes former division_by_zero class;
   623   - numerous lemmas have been ported from field to division_ring.
   624 INCOMPATIBILITY.
   625 
   626 * Refined algebra theorem collections:
   627   - dropped theorem group group_simps, use algebra_simps instead;
   628   - dropped theorem group ring_simps, use field_simps instead;
   629   - proper theorem collection field_simps subsumes former theorem
   630     groups field_eq_simps and field_simps;
   631   - dropped lemma eq_minus_self_iff which is a duplicate for
   632     equal_neg_zero.
   633 INCOMPATIBILITY.
   634 
   635 * Theory Finite_Set and List: some lemmas have been generalized from
   636 sets to lattices:
   637 
   638   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   639   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   640   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   641   union_Union_fold_union        ~> sup_Sup_fold_sup
   642   Inter_fold_inter              ~> Inf_fold_inf
   643   Union_fold_union              ~> Sup_fold_sup
   644   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   645   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   646   INTER_fold_inter              ~> INFI_fold_inf
   647   UNION_fold_union              ~> SUPR_fold_sup
   648 
   649 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   650 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   651 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   652 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   653 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   654 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   655 
   656 * Reorganized theory Multiset: swapped notation of pointwise and
   657 multiset order:
   658 
   659   - pointwise ordering is instance of class order with standard syntax
   660     <= and <;
   661   - multiset ordering has syntax <=# and <#; partial order properties
   662     are provided by means of interpretation with prefix
   663     multiset_order;
   664   - less duplication, less historical organization of sections,
   665     conversion from associations lists to multisets, rudimentary code
   666     generation;
   667   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   668     if needed.
   669 
   670 Renamed:
   671 
   672   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   673   multi_count_ext  ~>  multiset_ext
   674   diff_union_inverse2  ~>  diff_union_cancelR
   675 
   676 INCOMPATIBILITY.
   677 
   678 * Theory Permutation: replaced local "remove" by List.remove1.
   679 
   680 * Code generation: ML and OCaml code is decorated with signatures.
   681 
   682 * Theory List: added transpose.
   683 
   684 * Library/Nat_Bijection.thy is a collection of bijective functions
   685 between nat and other types, which supersedes the older libraries
   686 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   687 
   688   Constants:
   689   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   690   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   691   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   692   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   693   Countable.pair_encode           ~> prod_encode
   694   NatIso.prod2nat                 ~> prod_encode
   695   NatIso.nat2prod                 ~> prod_decode
   696   NatIso.sum2nat                  ~> sum_encode
   697   NatIso.nat2sum                  ~> sum_decode
   698   NatIso.list2nat                 ~> list_encode
   699   NatIso.nat2list                 ~> list_decode
   700   NatIso.set2nat                  ~> set_encode
   701   NatIso.nat2set                  ~> set_decode
   702 
   703   Lemmas:
   704   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   705   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   706   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   707   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   708   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   709   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   710   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   711   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   712   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   713   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   714   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   715   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   716   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   717 
   718 * Sledgehammer:
   719   - Renamed ATP commands:
   720     atp_info     ~> sledgehammer running_atps
   721     atp_kill     ~> sledgehammer kill_atps
   722     atp_messages ~> sledgehammer messages
   723     atp_minimize ~> sledgehammer minimize
   724     print_atps   ~> sledgehammer available_atps
   725     INCOMPATIBILITY.
   726   - Added user's manual ("isabelle doc sledgehammer").
   727   - Added option syntax and "sledgehammer_params" to customize
   728     Sledgehammer's behavior.  See the manual for details.
   729   - Modified the Isar proof reconstruction code so that it produces
   730     direct proofs rather than proofs by contradiction.  (This feature
   731     is still experimental.)
   732   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   733     full-typed mode.
   734   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   735 
   736 * Nitpick:
   737   - Added and implemented "binary_ints" and "bits" options.
   738   - Added "std" option and implemented support for nonstandard models.
   739   - Added and implemented "finitize" option to improve the precision
   740     of infinite datatypes based on a monotonicity analysis.
   741   - Added support for quotient types.
   742   - Added support for "specification" and "ax_specification"
   743     constructs.
   744   - Added support for local definitions (for "function" and
   745     "termination" proofs).
   746   - Added support for term postprocessors.
   747   - Optimized "Multiset.multiset" and "FinFun.finfun".
   748   - Improved efficiency of "destroy_constrs" optimization.
   749   - Fixed soundness bugs related to "destroy_constrs" optimization and
   750     record getters.
   751   - Fixed soundness bug related to higher-order constructors.
   752   - Fixed soundness bug when "full_descrs" is enabled.
   753   - Improved precision of set constructs.
   754   - Added "atoms" option.
   755   - Added cache to speed up repeated Kodkod invocations on the same
   756     problems.
   757   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   758     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   759     "SAT4J_Light".  INCOMPATIBILITY.
   760   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   761     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   762   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   763 
   764 * Method "induct" now takes instantiations of the form t, where t is not
   765   a variable, as a shorthand for "x == t", where x is a fresh variable.
   766   If this is not intended, t has to be enclosed in parentheses.
   767   By default, the equalities generated by definitional instantiations
   768   are pre-simplified, which may cause parameters of inductive cases
   769   to disappear, or may even delete some of the inductive cases.
   770   Use "induct (no_simp)" instead of "induct" to restore the old
   771   behaviour. The (no_simp) option is also understood by the "cases"
   772   and "nominal_induct" methods, which now perform pre-simplification, too.
   773   INCOMPATIBILITY.
   774 
   775 
   776 *** HOLCF ***
   777 
   778 * Variable names in lemmas generated by the domain package have
   779 changed; the naming scheme is now consistent with the HOL datatype
   780 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   781 
   782 * The domain package no longer defines the function "foo_copy" for
   783 recursive domain "foo".  The reach lemma is now stated directly in
   784 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   785 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   786 
   787 * Most definedness lemmas generated by the domain package (previously
   788 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   789 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   790 Proofs that used definedness lemmas as intro rules may break,
   791 potential INCOMPATIBILITY.
   792 
   793 * Induction and casedist rules generated by the domain package now
   794 declare proper case_names (one called "bottom", and one named for each
   795 constructor).  INCOMPATIBILITY.
   796 
   797 * For mutually-recursive domains, separate "reach" and "take_lemma"
   798 rules are generated for each domain, INCOMPATIBILITY.
   799 
   800   foo_bar.reach       ~> foo.reach  bar.reach
   801   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   802 
   803 * Some lemmas generated by the domain package have been renamed for
   804 consistency with the datatype package, INCOMPATIBILITY.
   805 
   806   foo.ind        ~> foo.induct
   807   foo.finite_ind ~> foo.finite_induct
   808   foo.coind      ~> foo.coinduct
   809   foo.casedist   ~> foo.exhaust
   810   foo.exhaust    ~> foo.nchotomy
   811 
   812 * For consistency with other definition packages, the fixrec package
   813 now generates qualified theorem names, INCOMPATIBILITY.
   814 
   815   foo_simps  ~> foo.simps
   816   foo_unfold ~> foo.unfold
   817   foo_induct ~> foo.induct
   818 
   819 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   820 method and internal fixrec proofs now use the default simpset instead.
   821 INCOMPATIBILITY.
   822 
   823 * The "contlub" predicate has been removed.  Proof scripts should use
   824 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   825 
   826 * The "admw" predicate has been removed, INCOMPATIBILITY.
   827 
   828 * The constants cpair, cfst, and csnd have been removed in favor of
   829 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   830 
   831 
   832 *** ML ***
   833 
   834 * Antiquotations for basic formal entities:
   835 
   836     @{class NAME}         -- type class
   837     @{class_syntax NAME}  -- syntax representation of the above
   838 
   839     @{type_name NAME}     -- logical type
   840     @{type_abbrev NAME}   -- type abbreviation
   841     @{nonterminal NAME}   -- type of concrete syntactic category
   842     @{type_syntax NAME}   -- syntax representation of any of the above
   843 
   844     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   845     @{const_abbrev NAME}  -- abbreviated constant
   846     @{const_syntax NAME}  -- syntax representation of any of the above
   847 
   848 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   849 syntax constant (cf. 'syntax' command).
   850 
   851 * Antiquotation @{make_string} inlines a function to print arbitrary
   852 values similar to the ML toplevel.  The result is compiler dependent
   853 and may fall back on "?" in certain situations.
   854 
   855 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   856 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   857 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   858 not work with the asynchronous Isar document model.
   859 
   860 * Configuration options now admit dynamic default values, depending on
   861 the context or even global references.
   862 
   863 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   864 uses an efficient external library if available (for Poly/ML).
   865 
   866 * Renamed some important ML structures, while keeping the old names
   867 for some time as aliases within the structure Legacy:
   868 
   869   OuterKeyword  ~>  Keyword
   870   OuterLex      ~>  Token
   871   OuterParse    ~>  Parse
   872   OuterSyntax   ~>  Outer_Syntax
   873   PrintMode     ~>  Print_Mode
   874   SpecParse     ~>  Parse_Spec
   875   ThyInfo       ~>  Thy_Info
   876   ThyLoad       ~>  Thy_Load
   877   ThyOutput     ~>  Thy_Output
   878   TypeInfer     ~>  Type_Infer
   879 
   880 Note that "open Legacy" simplifies porting of sources, but forgetting
   881 to remove it again will complicate porting again in the future.
   882 
   883 * Most operations that refer to a global context are named
   884 accordingly, e.g. Simplifier.global_context or
   885 ProofContext.init_global.  There are some situations where a global
   886 context actually works, but under normal circumstances one needs to
   887 pass the proper local context through the code!
   888 
   889 * Discontinued old TheoryDataFun with its copy/init operation -- data
   890 needs to be pure.  Functor Theory_Data_PP retains the traditional
   891 Pretty.pp argument to merge, which is absent in the standard
   892 Theory_Data version.
   893 
   894 * Sorts.certify_sort and derived "cert" operations for types and terms
   895 no longer minimize sorts.  Thus certification at the boundary of the
   896 inference kernel becomes invariant under addition of class relations,
   897 which is an important monotonicity principle.  Sorts are now minimized
   898 in the syntax layer only, at the boundary between the end-user and the
   899 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   900 explicitly in rare situations.
   901 
   902 * Renamed old-style Drule.standard to Drule.export_without_context, to
   903 emphasize that this is in no way a standard operation.
   904 INCOMPATIBILITY.
   905 
   906 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   907 usual for resolution.  Rare INCOMPATIBILITY.
   908 
   909 * Renamed varify/unvarify operations to varify_global/unvarify_global
   910 to emphasize that these only work in a global situation (which is
   911 quite rare).
   912 
   913 * Curried take and drop in library.ML; negative length is interpreted
   914 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   915 
   916 * Proof terms: type substitutions on proof constants now use canonical
   917 order of type variables.  INCOMPATIBILITY for tools working with proof
   918 terms.
   919 
   920 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   921 may no longer carry premises.  User-level specifications are
   922 transformed accordingly by Thm.add_axiom/add_def.
   923 
   924 
   925 *** System ***
   926 
   927 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   928 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   929 proof terms are enabled unconditionally in the new HOL-Proofs image.
   930 
   931 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   932 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   933 respectively.
   934 
   935 * Old lib/scripts/polyml-platform is superseded by the
   936 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   937 variant, even on a 64 bit machine.  The following example setting
   938 prefers 64 bit if available:
   939 
   940   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   941 
   942 * The preliminary Isabelle/jEdit application demonstrates the emerging
   943 Isabelle/Scala layer for advanced prover interaction and integration.
   944 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   945 component.
   946 
   947 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   948 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   949 similar to the default assignment of the document preparation system
   950 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   951 provides some operations for direct access to the font without asking
   952 the user for manual installation.
   953 
   954 
   955 
   956 New in Isabelle2009-1 (December 2009)
   957 -------------------------------------
   958 
   959 *** General ***
   960 
   961 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   962 one backslash should be used, even in ML sources.
   963 
   964 
   965 *** Pure ***
   966 
   967 * Locale interpretation propagates mixins along the locale hierarchy.
   968 The currently only available mixins are the equations used to map
   969 local definitions to terms of the target domain of an interpretation.
   970 
   971 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   972 loc" to print all interpretations of locale "loc" in the theory.
   973 Interpretations in proofs are not shown.
   974 
   975 * Thoroughly revised locales tutorial.  New section on conditional
   976 interpretation.
   977 
   978 * On instantiation of classes, remaining undefined class parameters
   979 are formally declared.  INCOMPATIBILITY.
   980 
   981 
   982 *** Document preparation ***
   983 
   984 * New generalized style concept for printing terms: @{foo (style) ...}
   985 instead of @{foo_style style ...}  (old form is still retained for
   986 backward compatibility).  Styles can be also applied for
   987 antiquotations prop, term_type and typeof.
   988 
   989 
   990 *** HOL ***
   991 
   992 * New proof method "smt" for a combination of first-order logic with
   993 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   994 fixed-size bitvectors; there is also basic support for higher-order
   995 features (esp. lambda abstractions).  It is an incomplete decision
   996 procedure based on external SMT solvers using the oracle mechanism;
   997 for the SMT solver Z3, this method is proof-producing.  Certificates
   998 are provided to avoid calling the external solvers solely for
   999 re-checking proofs.  Due to a remote SMT service there is no need for
  1000 installing SMT solvers locally.  See src/HOL/SMT.
  1001 
  1002 * New commands to load and prove verification conditions generated by
  1003 the Boogie program verifier or derived systems (e.g. the Verifying C
  1004 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1005 
  1006 * New counterexample generator tool 'nitpick' based on the Kodkod
  1007 relational model finder.  See src/HOL/Tools/Nitpick and
  1008 src/HOL/Nitpick_Examples.
  1009 
  1010 * New commands 'code_pred' and 'values' to invoke the predicate
  1011 compiler and to enumerate values of inductive predicates.
  1012 
  1013 * A tabled implementation of the reflexive transitive closure.
  1014 
  1015 * New implementation of quickcheck uses generic code generator;
  1016 default generators are provided for all suitable HOL types, records
  1017 and datatypes.  Old quickcheck can be re-activated importing theory
  1018 Library/SML_Quickcheck.
  1019 
  1020 * New testing tool Mirabelle for automated proof tools.  Applies
  1021 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1022 every proof step in a theory.  To be used in batch mode via the
  1023 "mirabelle" utility.
  1024 
  1025 * New proof method "sos" (sum of squares) for nonlinear real
  1026 arithmetic (originally due to John Harison). It requires theory
  1027 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1028 works well in practice on quantifier-free real arithmetic with +, -,
  1029 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1030 inequalities between polynomials.  It makes use of external
  1031 semidefinite programming solvers.  Method "sos" generates a
  1032 certificate that can be pasted into the proof thus avoiding the need
  1033 to call an external tool every time the proof is checked.  See
  1034 src/HOL/Library/Sum_Of_Squares.
  1035 
  1036 * New method "linarith" invokes existing linear arithmetic decision
  1037 procedure only.
  1038 
  1039 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1040 
  1041 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1042 Causes full type information to be output to the ATPs.  This slows
  1043 ATPs down considerably but eliminates a source of unsound "proofs"
  1044 that fail later.
  1045 
  1046 * New method "metisFT": A version of metis that uses full type
  1047 information in order to avoid failures of proof reconstruction.
  1048 
  1049 * New evaluator "approximate" approximates an real valued term using
  1050 the same method as the approximation method.
  1051 
  1052 * Method "approximate" now supports arithmetic expressions as
  1053 boundaries of intervals and implements interval splitting and Taylor
  1054 series expansion.
  1055 
  1056 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1057 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1058 
  1059 * New theory SupInf of the supremum and infimum operators for sets of
  1060 reals.
  1061 
  1062 * New theory Probability, which contains a development of measure
  1063 theory, eventually leading to Lebesgue integration and probability.
  1064 
  1065 * Extended Multivariate Analysis to include derivation and Brouwer's
  1066 fixpoint theorem.
  1067 
  1068 * Reorganization of number theory, INCOMPATIBILITY:
  1069   - new number theory development for nat and int, in theories Divides
  1070     and GCD as well as in new session Number_Theory
  1071   - some constants and facts now suffixed with _nat and _int
  1072     accordingly
  1073   - former session NumberTheory now named Old_Number_Theory, including
  1074     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1075   - moved theory Pocklington from src/HOL/Library to
  1076     src/HOL/Old_Number_Theory
  1077 
  1078 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1079 lcm of finite and infinite sets. It is shown that they form a complete
  1080 lattice.
  1081 
  1082 * Class semiring_div requires superclass no_zero_divisors and proof of
  1083 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1084 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1085 generalized to class semiring_div, subsuming former theorems
  1086 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1087 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1088 INCOMPATIBILITY.
  1089 
  1090 * Refinements to lattice classes and sets:
  1091   - less default intro/elim rules in locale variant, more default
  1092     intro/elim rules in class variant: more uniformity
  1093   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1094     le_inf_iff
  1095   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1096     sup_aci)
  1097   - renamed ACI to inf_sup_aci
  1098   - new class "boolean_algebra"
  1099   - class "complete_lattice" moved to separate theory
  1100     "Complete_Lattice"; corresponding constants (and abbreviations)
  1101     renamed and with authentic syntax:
  1102     Set.Inf ~>    Complete_Lattice.Inf
  1103     Set.Sup ~>    Complete_Lattice.Sup
  1104     Set.INFI ~>   Complete_Lattice.INFI
  1105     Set.SUPR ~>   Complete_Lattice.SUPR
  1106     Set.Inter ~>  Complete_Lattice.Inter
  1107     Set.Union ~>  Complete_Lattice.Union
  1108     Set.INTER ~>  Complete_Lattice.INTER
  1109     Set.UNION ~>  Complete_Lattice.UNION
  1110   - authentic syntax for
  1111     Set.Pow
  1112     Set.image
  1113   - mere abbreviations:
  1114     Set.empty               (for bot)
  1115     Set.UNIV                (for top)
  1116     Set.inter               (for inf, formerly Set.Int)
  1117     Set.union               (for sup, formerly Set.Un)
  1118     Complete_Lattice.Inter  (for Inf)
  1119     Complete_Lattice.Union  (for Sup)
  1120     Complete_Lattice.INTER  (for INFI)
  1121     Complete_Lattice.UNION  (for SUPR)
  1122   - object-logic definitions as far as appropriate
  1123 
  1124 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1125 Un_subset_iff are explicitly deleted as default simp rules; then also
  1126 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1127 deleted to achieve the desired effect.
  1128 
  1129 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1130 rules by default any longer; the same applies to min_max.inf_absorb1
  1131 etc.  INCOMPATIBILITY.
  1132 
  1133 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1134 pred_set_conv by default.  INCOMPATIBILITY.
  1135 
  1136 * Power operations on relations and functions are now one dedicated
  1137 constant "compow" with infix syntax "^^".  Power operation on
  1138 multiplicative monoids retains syntax "^" and is now defined generic
  1139 in class power.  INCOMPATIBILITY.
  1140 
  1141 * Relation composition "R O S" now has a more standard argument order:
  1142 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1143 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1144 break, since the O_assoc rule was not rewritten like this.  Fix using
  1145 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1146 
  1147 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1148 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1149 INCOMPATIBILITY.
  1150 
  1151 * Most rules produced by inductive and datatype package have mandatory
  1152 prefixes.  INCOMPATIBILITY.
  1153 
  1154 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1155 the attribute of the same name.  Each of the theorems in the list
  1156 DERIV_intros assumes composition with an additional function and
  1157 matches a variable to the derivative, which has to be solved by the
  1158 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1159 of most elementary terms.  Former Maclauren.DERIV_tac and
  1160 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1161 INCOMPATIBILITY.
  1162 
  1163 * Code generator attributes follow the usual underscore convention:
  1164     code_unfold     replaces    code unfold
  1165     code_post       replaces    code post
  1166     etc.
  1167   INCOMPATIBILITY.
  1168 
  1169 * Renamed methods:
  1170     sizechange -> size_change
  1171     induct_scheme -> induction_schema
  1172   INCOMPATIBILITY.
  1173 
  1174 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1175 INCOMPATIBILITY, use "undefined" directly.
  1176 
  1177 * Renamed theorems:
  1178     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1179     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1180     Suc_plus1 -> Suc_eq_plus1
  1181     *anti_sym -> *antisym*
  1182     vector_less_eq_def -> vector_le_def
  1183   INCOMPATIBILITY.
  1184 
  1185 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1186 INCOMPATIBILITY.
  1187 
  1188 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1189 INCOMPATIBILITY.
  1190 
  1191 
  1192 *** HOLCF ***
  1193 
  1194 * Theory Representable defines a class "rep" of domains that are
  1195 representable (via an ep-pair) in the universal domain type "udom".
  1196 Instances are provided for all type constructors defined in HOLCF.
  1197 
  1198 * The 'new_domain' command is a purely definitional version of the
  1199 domain package, for representable domains.  Syntax is identical to the
  1200 old domain package.  The 'new_domain' package also supports indirect
  1201 recursion using previously-defined type constructors.  See
  1202 src/HOLCF/ex/New_Domain.thy for examples.
  1203 
  1204 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1205 on the left-hand side of an equation, and then performs
  1206 simplification.  Rewriting is done using rules declared with the
  1207 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1208 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1209 
  1210 * The pattern-match compiler in 'fixrec' can now handle constructors
  1211 with HOL function types.  Pattern-match combinators for the Pair
  1212 constructor are pre-configured.
  1213 
  1214 * The 'fixrec' package now produces better fixed-point induction rules
  1215 for mutually-recursive definitions:  Induction rules have conclusions
  1216 of the form "P foo bar" instead of "P <foo, bar>".
  1217 
  1218 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1219 been renamed to "below".  The name "below" now replaces "less" in many
  1220 theorem names.  (Legacy theorem names using "less" are still supported
  1221 as well.)
  1222 
  1223 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1224 patterns can be used to generate strictness rules, or to make
  1225 functions more strict (much like the bang-patterns supported by the
  1226 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1227 examples.
  1228 
  1229 
  1230 *** ML ***
  1231 
  1232 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1233 errors and run-time exceptions, including detailed source positions.
  1234 
  1235 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1236 identified entries, with some additional information such as source
  1237 position, logical grouping etc.
  1238 
  1239 * Theory and context data is now introduced by the simplified and
  1240 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1241 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1242 copy operation) is still available for some time.
  1243 
  1244 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1245 provides a high-level programming interface to synchronized state
  1246 variables with atomic update.  This works via pure function
  1247 application within a critical section -- its runtime should be as
  1248 short as possible; beware of deadlocks if critical code is nested,
  1249 either directly or indirectly via other synchronized variables!
  1250 
  1251 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1252 wraps raw ML references, explicitly indicating their non-thread-safe
  1253 behaviour.  The Isar toplevel keeps this structure open, to
  1254 accommodate Proof General as well as quick and dirty interactive
  1255 experiments with references.
  1256 
  1257 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1258 parallel tactical reasoning.
  1259 
  1260 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1261 are similar to SUBPROOF, but are slightly more flexible: only the
  1262 specified parts of the subgoal are imported into the context, and the
  1263 body tactic may introduce new subgoals and schematic variables.
  1264 
  1265 * Old tactical METAHYPS, which does not observe the proof context, has
  1266 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1267 or Subgoal.FOCUS etc.
  1268 
  1269 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1270 functors have their own ML name space there is no point to mark them
  1271 separately.)  Minor INCOMPATIBILITY.
  1272 
  1273 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1274 
  1275 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1276 INCOMPATIBILITY.
  1277 
  1278 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1279 mode, which avoids critical setmp.
  1280 
  1281 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1282 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1283 Attrib/Method.setup introduced in Isabelle2009.
  1284 
  1285 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1286 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1287 last resort.  INCOMPATIBILITY.
  1288 
  1289 * Display.pretty_thm now requires a proper context (cf. former
  1290 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1291 or even Display.pretty_thm_without_context as last resort.
  1292 INCOMPATIBILITY.
  1293 
  1294 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1295 Syntax.pretty_typ/term directly, preferably with proper context
  1296 instead of global theory.
  1297 
  1298 
  1299 *** System ***
  1300 
  1301 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1302 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1303 usedir option -q.
  1304 
  1305 * Support for additional "Isabelle components" via etc/components, see
  1306 also the system manual.
  1307 
  1308 * The isabelle makeall tool now operates on all components with
  1309 IsaMakefile, not just hardwired "logics".
  1310 
  1311 * Removed "compress" option from isabelle-process and isabelle usedir;
  1312 this is always enabled.
  1313 
  1314 * Discontinued support for Poly/ML 4.x versions.
  1315 
  1316 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1317 on a given logic image.  This requires the lighttpd webserver and is
  1318 currently supported on Linux only.
  1319 
  1320 
  1321 
  1322 New in Isabelle2009 (April 2009)
  1323 --------------------------------
  1324 
  1325 *** General ***
  1326 
  1327 * Simplified main Isabelle executables, with less surprises on
  1328 case-insensitive file-systems (such as Mac OS).
  1329 
  1330   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1331     "isatool."
  1332 
  1333   - The former "isabelle" alias for "isabelle-process" has been
  1334     removed (should rarely occur to regular users).
  1335 
  1336   - The former "isabelle-interface" and its alias "Isabelle" have been
  1337     removed (interfaces are now regular Isabelle tools).
  1338 
  1339 Within scripts and make files, the Isabelle environment variables
  1340 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1341 respectively.  (The latter are still available as legacy feature.)
  1342 
  1343 The old isabelle-interface wrapper could react in confusing ways if
  1344 the interface was uninstalled or changed otherwise.  Individual
  1345 interface tool configuration is now more explicit, see also the
  1346 Isabelle system manual.  In particular, Proof General is now available
  1347 via "isabelle emacs".
  1348 
  1349 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1350 purge installed copies of Isabelle executables and re-run "isabelle
  1351 install -p ...", or use symlinks.
  1352 
  1353 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1354 old ~/isabelle, which was slightly non-standard and apt to cause
  1355 surprises on case-insensitive file-systems (such as Mac OS).
  1356 
  1357 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1358 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1359 care is required when using older releases of Isabelle.  Note that
  1360 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1361 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1362 
  1363 * Proofs of fully specified statements are run in parallel on
  1364 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1365 a regular 4-core machine, if the initial heap space is made reasonably
  1366 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1367 
  1368 * The main reference manuals ("isar-ref", "implementation", and
  1369 "system") have been updated and extended.  Formally checked references
  1370 as hyperlinks are now available uniformly.
  1371 
  1372 
  1373 *** Pure ***
  1374 
  1375 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1376 respects.  The most important changes are listed below.  See the
  1377 Tutorial on Locales ("locales" manual) for details.
  1378 
  1379 - In locale expressions, instantiation replaces renaming.  Parameters
  1380 must be declared in a for clause.  To aid compatibility with previous
  1381 parameter inheritance, in locale declarations, parameters that are not
  1382 'touched' (instantiation position "_" or omitted) are implicitly added
  1383 with their syntax at the beginning of the for clause.
  1384 
  1385 - Syntax from abbreviations and definitions in locales is available in
  1386 locale expressions and context elements.  The latter is particularly
  1387 useful in locale declarations.
  1388 
  1389 - More flexible mechanisms to qualify names generated by locale
  1390 expressions.  Qualifiers (prefixes) may be specified in locale
  1391 expressions, and can be marked as mandatory (syntax: "name!:") or
  1392 optional (syntax "name?:").  The default depends for plain "name:"
  1393 depends on the situation where a locale expression is used: in
  1394 commands 'locale' and 'sublocale' prefixes are optional, in
  1395 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1396 implicit qualifiers derived from the parameter names of a locale are
  1397 no longer generated.
  1398 
  1399 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1400 instantiation clause in "interpretation" and "interpret" (square
  1401 brackets) is no longer available.  Use locale expressions.
  1402 
  1403 - When converting proof scripts, mandatory qualifiers in
  1404 'interpretation' and 'interpret' should be retained by default, even
  1405 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1406 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1407 in locale expressions range over a single locale instance only.
  1408 
  1409 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1410 In existing theorem specifications replace the includes element by the
  1411 respective context elements of the included locale, omitting those
  1412 that are already present in the theorem specification.  Multiple
  1413 assume elements of a locale should be replaced by a single one
  1414 involving the locale predicate.  In the proof body, declarations (most
  1415 notably theorems) may be regained by interpreting the respective
  1416 locales in the proof context as required (command "interpret").
  1417 
  1418 If using "includes" in replacement of a target solely because the
  1419 parameter types in the theorem are not as general as in the target,
  1420 consider declaring a new locale with additional type constraints on
  1421 the parameters (context element "constrains").
  1422 
  1423 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1424 
  1425 - Locale interpretation commands no longer attempt to simplify goal.
  1426 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1427 methods intro_locales and unfold_locales to clarify.
  1428 
  1429 - Locale interpretation commands no longer accept interpretation
  1430 attributes.  INCOMPATIBILITY.
  1431 
  1432 * Class declaration: so-called "base sort" must not be given in import
  1433 list any longer, but is inferred from the specification.  Particularly
  1434 in HOL, write
  1435 
  1436     class foo = ...
  1437 
  1438 instead of
  1439 
  1440     class foo = type + ...
  1441 
  1442 * Class target: global versions of theorems stemming do not carry a
  1443 parameter prefix any longer.  INCOMPATIBILITY.
  1444 
  1445 * Class 'instance' command no longer accepts attached definitions.
  1446 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1447 
  1448 * Recovered hiding of consts, which was accidentally broken in
  1449 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1450 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1451 
  1452 * Slightly more coherent Pure syntax, with updated documentation in
  1453 isar-ref manual.  Removed locales meta_term_syntax and
  1454 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1455 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1456 directly in regular applications.
  1457 
  1458 * There is a new syntactic category "float_const" for signed decimal
  1459 fractions (e.g. 123.45 or -123.45).
  1460 
  1461 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1462 interface with 'setup' command instead.
  1463 
  1464 * Command 'local_setup' is similar to 'setup', but operates on a local
  1465 theory context.
  1466 
  1467 * The 'axiomatization' command now only works within a global theory
  1468 context.  INCOMPATIBILITY.
  1469 
  1470 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1471 hypotheses.  Sorts required in the course of reasoning need to be
  1472 covered by the constraints in the initial statement, completed by the
  1473 type instance information of the background theory.  Non-trivial sort
  1474 hypotheses, which rarely occur in practice, may be specified via
  1475 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1476 
  1477   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1478 
  1479 The result contains an implicit sort hypotheses as before --
  1480 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1481 normalization.
  1482 
  1483 * Generalized Isar history, with support for linear undo, direct state
  1484 addressing etc.
  1485 
  1486 * Changed defaults for unify configuration options:
  1487 
  1488   unify_trace_bound = 50 (formerly 25)
  1489   unify_search_bound = 60 (formerly 30)
  1490 
  1491 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1492 
  1493   a) On theory merge, the last set of code equations for a particular
  1494      constant is taken (in accordance with the policy applied by other
  1495      parts of the code generator framework).
  1496 
  1497   b) Code equations stemming from explicit declarations (e.g. code
  1498      attribute) gain priority over default code equations stemming
  1499      from definition, primrec, fun etc.
  1500 
  1501 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1502 
  1503 * Unified theorem tables for both code generators.  Thus [code
  1504 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1505 
  1506 * Command 'find_consts' searches for constants based on type and name
  1507 patterns, e.g.
  1508 
  1509     find_consts "_ => bool"
  1510 
  1511 By default, matching is against subtypes, but it may be restricted to
  1512 the whole type.  Searching by name is possible.  Multiple queries are
  1513 conjunctive and queries may be negated by prefixing them with a
  1514 hyphen:
  1515 
  1516     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1517 
  1518 * New 'find_theorems' criterion "solves" matches theorems that
  1519 directly solve the current goal (modulo higher-order unification).
  1520 
  1521 * Auto solve feature for main theorem statements: whenever a new goal
  1522 is stated, "find_theorems solves" is called; any theorems that could
  1523 solve the lemma directly are listed as part of the goal state.
  1524 Cf. associated options in Proof General Isabelle settings menu,
  1525 enabled by default, with reasonable timeout for pathological cases of
  1526 higher-order unification.
  1527 
  1528 
  1529 *** Document preparation ***
  1530 
  1531 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1532 demanding keyword 'by' and supporting the full method expression
  1533 syntax just like the Isar command 'by'.
  1534 
  1535 
  1536 *** HOL ***
  1537 
  1538 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1539 points Main and Complex_Main remain as before.
  1540 
  1541 * Logic image HOL-Plain provides a minimal HOL with the most important
  1542 tools available (inductive, datatype, primrec, ...).  This facilitates
  1543 experimentation and tool development.  Note that user applications
  1544 (and library theories) should never refer to anything below theory
  1545 Main, as before.
  1546 
  1547 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1548 experimentation due to shorter build times.
  1549 
  1550 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1551 were previously part of former HOL-Complex.  Entry point Hyperreal
  1552 remains valid, but theories formerly using Complex_Main should now use
  1553 new entry point Hypercomplex.
  1554 
  1555 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1556 Posix processes.  Avoids potentially expensive forking of the ML
  1557 process.  New thread-based implementation also works on non-Unix
  1558 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1559 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1560 commands are covered in the isar-ref manual.
  1561 
  1562 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1563 sledgehammer without local ATP installation (Vampire etc.). Other
  1564 provers may be included via suitable ML wrappers, see also
  1565 src/HOL/ATP_Linkup.thy.
  1566 
  1567 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1568 menu.
  1569 
  1570 * The metis method no longer fails because the theorem is too trivial
  1571 (contains the empty clause).
  1572 
  1573 * The metis method now fails in the usual manner, rather than raising
  1574 an exception, if it determines that it cannot prove the theorem.
  1575 
  1576 * Method "coherent" implements a prover for coherent logic (see also
  1577 src/Tools/coherent.ML).
  1578 
  1579 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1580 "undefined" is the right choice to replace "arbitrary", though
  1581 logically there is no difference.  INCOMPATIBILITY.
  1582 
  1583 * Command "value" now integrates different evaluation mechanisms.  The
  1584 result of the first successful evaluation mechanism is printed.  In
  1585 square brackets a particular named evaluation mechanisms may be
  1586 specified (currently, [SML], [code] or [nbe]).  See further
  1587 src/HOL/ex/Eval_Examples.thy.
  1588 
  1589 * Normalization by evaluation now allows non-leftlinear equations.
  1590 Declare with attribute [code nbe].
  1591 
  1592 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1593 as the structured Isar versions "cases" and "induct", cf. the
  1594 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1595 are now presented as a list of individual projections
  1596 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1597 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1598 rare situations a different rule is selected --- notably nested tuple
  1599 elimination instead of former prod.exhaust: use explicit (case_tac t
  1600 rule: prod.exhaust) here.
  1601 
  1602 * Attributes "cases", "induct", "coinduct" support "del" option.
  1603 
  1604 * Removed fact "case_split_thm", which duplicates "case_split".
  1605 
  1606 * The option datatype has been moved to a new theory Option.  Renamed
  1607 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1608 
  1609 * New predicate "strict_mono" classifies strict functions on partial
  1610 orders.  With strict functions on linear orders, reasoning about
  1611 (in)equalities is facilitated by theorems "strict_mono_eq",
  1612 "strict_mono_less_eq" and "strict_mono_less".
  1613 
  1614 * Some set operations are now proper qualified constants with
  1615 authentic syntax.  INCOMPATIBILITY:
  1616 
  1617     op Int ~>   Set.Int
  1618     op Un ~>    Set.Un
  1619     INTER ~>    Set.INTER
  1620     UNION ~>    Set.UNION
  1621     Inter ~>    Set.Inter
  1622     Union ~>    Set.Union
  1623     {} ~>       Set.empty
  1624     UNIV ~>     Set.UNIV
  1625 
  1626 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1627 theory Set.
  1628 
  1629 * Auxiliary class "itself" has disappeared -- classes without any
  1630 parameter are treated as expected by the 'class' command.
  1631 
  1632 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1633 
  1634 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1635 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1636 
  1637 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1638 method "approximation".  It proves formulas on real values by using
  1639 interval arithmetic.  In the formulas are also the transcendental
  1640 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1641 allowed. For examples see
  1642 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1643 
  1644 * Theory "Reflection" now resides in HOL/Library.
  1645 
  1646 * Entry point to Word library now simply named "Word".
  1647 INCOMPATIBILITY.
  1648 
  1649 * Made source layout more coherent with logical distribution
  1650 structure:
  1651 
  1652     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1653     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1654     src/HOL/Library/GCD.thy ~> src/HOL/
  1655     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1656     src/HOL/Library/Parity.thy ~> src/HOL/
  1657     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1658     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1659     src/HOL/Real/Lubs.thy ~> src/HOL/
  1660     src/HOL/Real/PReal.thy ~> src/HOL/
  1661     src/HOL/Real/Rational.thy ~> src/HOL/
  1662     src/HOL/Real/RComplete.thy ~> src/HOL/
  1663     src/HOL/Real/RealDef.thy ~> src/HOL/
  1664     src/HOL/Real/RealPow.thy ~> src/HOL/
  1665     src/HOL/Real/Real.thy ~> src/HOL/
  1666     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1667     src/HOL/Complex/Complex.thy ~> src/HOL/
  1668     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1669     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1670     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1671     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1672     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1673     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1674     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1675     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1676     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1677     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1678     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1679     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1680     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1681     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1682     src/HOL/Real/Float ~> src/HOL/Library/
  1683     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1684     src/HOL/Real/RealVector.thy ~> src/HOL/
  1685 
  1686     src/HOL/arith_data.ML ~> src/HOL/Tools
  1687     src/HOL/hologic.ML ~> src/HOL/Tools
  1688     src/HOL/simpdata.ML ~> src/HOL/Tools
  1689     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1690     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1691     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1692     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1693     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1694     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1695     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1696 
  1697     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1698     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1699     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1700     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1701     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1702     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1703 
  1704 * If methods "eval" and "evaluation" encounter a structured proof
  1705 state with !!/==>, only the conclusion is evaluated to True (if
  1706 possible), avoiding strange error messages.
  1707 
  1708 * Method "sizechange" automates termination proofs using (a
  1709 modification of) the size-change principle.  Requires SAT solver.  See
  1710 src/HOL/ex/Termination.thy for examples.
  1711 
  1712 * Simplifier: simproc for let expressions now unfolds if bound
  1713 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1714 
  1715 * Method "arith": Linear arithmetic now ignores all inequalities when
  1716 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1717 
  1718 * New attribute "arith" for facts that should always be used
  1719 automatically by arithmetic. It is intended to be used locally in
  1720 proofs, e.g.
  1721 
  1722   assumes [arith]: "x > 0"
  1723 
  1724 Global usage is discouraged because of possible performance impact.
  1725 
  1726 * New classes "top" and "bot" with corresponding operations "top" and
  1727 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1728 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1729 
  1730 * Changed definition lemma "less_fun_def" in order to provide an
  1731 instance for preorders on functions; use lemma "less_le" instead.
  1732 INCOMPATIBILITY.
  1733 
  1734 * Theory Orderings: class "wellorder" moved here, with explicit
  1735 induction rule "less_induct" as assumption.  For instantiation of
  1736 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1737 INCOMPATIBILITY.
  1738 
  1739 * Theory Orderings: added class "preorder" as superclass of "order".
  1740 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1741 etc. slightly changed.  Some theorems named order_class.* now named
  1742 preorder_class.*.
  1743 
  1744 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1745 "diag" to "Id_on".
  1746 
  1747 * Theory Finite_Set: added a new fold combinator of type
  1748 
  1749   ('a => 'b => 'b) => 'b => 'a set => 'b
  1750 
  1751 Occasionally this is more convenient than the old fold combinator
  1752 which is now defined in terms of the new one and renamed to
  1753 fold_image.
  1754 
  1755 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1756 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1757 extended with further lemmas!).  At the moment both still exist but
  1758 the former will disappear at some point.
  1759 
  1760 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1761 class recpower.  Type-specific simp rules for various recpower types
  1762 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1763 
  1764 rat_power_0    -> power_0
  1765 rat_power_Suc  -> power_Suc
  1766 realpow_0      -> power_0
  1767 realpow_Suc    -> power_Suc
  1768 complexpow_0   -> power_0
  1769 complexpow_Suc -> power_Suc
  1770 power_poly_0   -> power_0
  1771 power_poly_Suc -> power_Suc
  1772 
  1773 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1774 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1775 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1776 of lemmas from Divides has been generalized from nat to class
  1777 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1778 renames resulting from duplicate elimination:
  1779 
  1780     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1781     zero_dvd_iff ~>         dvd_0_left_iff
  1782     dvd_0 ~>                dvd_0_right
  1783     DIVISION_BY_ZERO_DIV ~> div_by_0
  1784     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1785     mult_div ~>             div_mult_self2_is_id
  1786     mult_mod ~>             mod_mult_self2_is_0
  1787 
  1788 * Theory IntDiv: removed many lemmas that are instances of class-based
  1789 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1790 rename old lemmas as follows:
  1791 
  1792 dvd_diff               -> nat_dvd_diff
  1793 dvd_zminus_iff         -> dvd_minus_iff
  1794 mod_add1_eq            -> mod_add_eq
  1795 mod_mult1_eq           -> mod_mult_right_eq
  1796 mod_mult1_eq'          -> mod_mult_left_eq
  1797 mod_mult_distrib_mod   -> mod_mult_eq
  1798 nat_mod_add_left_eq    -> mod_add_left_eq
  1799 nat_mod_add_right_eq   -> mod_add_right_eq
  1800 nat_mod_div_trivial    -> mod_div_trivial
  1801 nat_mod_mod_trivial    -> mod_mod_trivial
  1802 zdiv_zadd_self1        -> div_add_self1
  1803 zdiv_zadd_self2        -> div_add_self2
  1804 zdiv_zmult_self1       -> div_mult_self2_is_id
  1805 zdiv_zmult_self2       -> div_mult_self1_is_id
  1806 zdvd_triv_left         -> dvd_triv_left
  1807 zdvd_triv_right        -> dvd_triv_right
  1808 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1809 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1810 zmod_zadd_left_eq      -> mod_add_left_eq
  1811 zmod_zadd_right_eq     -> mod_add_right_eq
  1812 zmod_zadd_self1        -> mod_add_self1
  1813 zmod_zadd_self2        -> mod_add_self2
  1814 zmod_zadd1_eq          -> mod_add_eq
  1815 zmod_zdiff1_eq         -> mod_diff_eq
  1816 zmod_zdvd_zmod         -> mod_mod_cancel
  1817 zmod_zmod_cancel       -> mod_mod_cancel
  1818 zmod_zmult_self1       -> mod_mult_self2_is_0
  1819 zmod_zmult_self2       -> mod_mult_self1_is_0
  1820 zmod_1                 -> mod_by_1
  1821 zdiv_1                 -> div_by_1
  1822 zdvd_abs1              -> abs_dvd_iff
  1823 zdvd_abs2              -> dvd_abs_iff
  1824 zdvd_refl              -> dvd_refl
  1825 zdvd_trans             -> dvd_trans
  1826 zdvd_zadd              -> dvd_add
  1827 zdvd_zdiff             -> dvd_diff
  1828 zdvd_zminus_iff        -> dvd_minus_iff
  1829 zdvd_zminus2_iff       -> minus_dvd_iff
  1830 zdvd_zmultD            -> dvd_mult_right
  1831 zdvd_zmultD2           -> dvd_mult_left
  1832 zdvd_zmult_mono        -> mult_dvd_mono
  1833 zdvd_0_right           -> dvd_0_right
  1834 zdvd_0_left            -> dvd_0_left_iff
  1835 zdvd_1_left            -> one_dvd
  1836 zminus_dvd_iff         -> minus_dvd_iff
  1837 
  1838 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1839 
  1840 * The real numbers offer decimal input syntax: 12.34 is translated
  1841 into 1234/10^2. This translation is not reversed upon output.
  1842 
  1843 * Theory Library/Polynomial defines an abstract type 'a poly of
  1844 univariate polynomials with coefficients of type 'a.  In addition to
  1845 the standard ring operations, it also supports div and mod.  Code
  1846 generation is also supported, using list-style constructors.
  1847 
  1848 * Theory Library/Inner_Product defines a class of real_inner for real
  1849 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1850 => real.  Class real_inner is a subclass of real_normed_vector from
  1851 theory RealVector.
  1852 
  1853 * Theory Library/Product_Vector provides instances for the product
  1854 type 'a * 'b of several classes from RealVector and Inner_Product.
  1855 Definitions of addition, subtraction, scalar multiplication, norms,
  1856 and inner products are included.
  1857 
  1858 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1859 addition to the field operations, numerals and case syntax are also
  1860 supported.
  1861 
  1862 * Theory Library/Diagonalize provides constructive version of Cantor's
  1863 first diagonalization argument.
  1864 
  1865 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1866 zlcm (for int); carried together from various gcd/lcm developements in
  1867 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1868 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1869 may recover tupled syntax as follows:
  1870 
  1871     hide (open) const gcd
  1872     abbreviation gcd where
  1873       "gcd == (%(a, b). GCD.gcd a b)"
  1874     notation (output)
  1875       GCD.gcd ("gcd '(_, _')")
  1876 
  1877 The same works for lcm, zgcd, zlcm.
  1878 
  1879 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1880 instantiations for algebraic structures.  Removed some duplicate
  1881 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1882 
  1883 * ML antiquotation @{code} takes a constant as argument and generates
  1884 corresponding code in background and inserts name of the corresponding
  1885 resulting ML value/function/datatype constructor binding in place.
  1886 All occurrences of @{code} with a single ML block are generated
  1887 simultaneously.  Provides a generic and safe interface for
  1888 instrumentalizing code generation.  See
  1889 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1890 In future you ought to refrain from ad-hoc compiling generated SML
  1891 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1892 cannot refer to constants for which user-defined serializations are
  1893 set.  Refer to the corresponding ML counterpart directly in that
  1894 cases.
  1895 
  1896 * Command 'rep_datatype': instead of theorem names the command now
  1897 takes a list of terms denoting the constructors of the type to be
  1898 represented as datatype.  The characteristic theorems have to be
  1899 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1900 have disappeared in favour of existing ones:
  1901 
  1902     unit_induct                 ~> unit.induct
  1903     prod_induct                 ~> prod.induct
  1904     sum_induct                  ~> sum.induct
  1905     Suc_Suc_eq                  ~> nat.inject
  1906     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1907 
  1908 
  1909 *** HOL-Algebra ***
  1910 
  1911 * New locales for orders and lattices where the equivalence relation
  1912 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1913 locales use a record structure with field eq for the equivalence.
  1914 
  1915 * New theory of factorial domains.
  1916 
  1917 * Units_l_inv and Units_r_inv are now simp rules by default.
  1918 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1919 and/or r_inv will now also require deletion of these lemmas.
  1920 
  1921 * Renamed the following theorems, INCOMPATIBILITY:
  1922 
  1923 UpperD ~> Upper_memD
  1924 LowerD ~> Lower_memD
  1925 least_carrier ~> least_closed
  1926 greatest_carrier ~> greatest_closed
  1927 greatest_Lower_above ~> greatest_Lower_below
  1928 one_zero ~> carrier_one_zero
  1929 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1930 
  1931 
  1932 *** HOL-Nominal ***
  1933 
  1934 * Nominal datatypes can now contain type-variables.
  1935 
  1936 * Commands 'nominal_inductive' and 'equivariance' work with local
  1937 theory targets.
  1938 
  1939 * Nominal primrec can now works with local theory targets and its
  1940 specification syntax now conforms to the general format as seen in
  1941 'inductive' etc.
  1942 
  1943 * Method "perm_simp" honours the standard simplifier attributes
  1944 (no_asm), (no_asm_use) etc.
  1945 
  1946 * The new predicate #* is defined like freshness, except that on the
  1947 left hand side can be a set or list of atoms.
  1948 
  1949 * Experimental command 'nominal_inductive2' derives strong induction
  1950 principles for inductive definitions.  In contrast to
  1951 'nominal_inductive', which can only deal with a fixed number of
  1952 binders, it can deal with arbitrary expressions standing for sets of
  1953 atoms to be avoided.  The only inductive definition we have at the
  1954 moment that needs this generalisation is the typing rule for Lets in
  1955 the algorithm W:
  1956 
  1957  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1958  -----------------------------------------------------------------
  1959          Gamma |- Let x be t1 in t2 : T2
  1960 
  1961 In this rule one wants to avoid all the binders that are introduced by
  1962 "close Gamma T1".  We are looking for other examples where this
  1963 feature might be useful.  Please let us know.
  1964 
  1965 
  1966 *** HOLCF ***
  1967 
  1968 * Reimplemented the simplification procedure for proving continuity
  1969 subgoals.  The new simproc is extensible; users can declare additional
  1970 continuity introduction rules with the attribute [cont2cont].
  1971 
  1972 * The continuity simproc now uses a different introduction rule for
  1973 solving continuity subgoals on terms with lambda abstractions.  In
  1974 some rare cases the new simproc may fail to solve subgoals that the
  1975 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1976 Potential INCOMPATIBILITY.
  1977 
  1978 * Command 'fixrec': specification syntax now conforms to the general
  1979 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1980 examples.  INCOMPATIBILITY.
  1981 
  1982 
  1983 *** ZF ***
  1984 
  1985 * Proof of Zorn's Lemma for partial orders.
  1986 
  1987 
  1988 *** ML ***
  1989 
  1990 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1991 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1992 depends on multithreading, so timouts will not work before Poly/ML
  1993 5.2.1!
  1994 
  1995 * High-level support for concurrent ML programming, see
  1996 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1997 particularly convenient to organize independent functional
  1998 computations.  The concept of "synchronized variables" provides a
  1999 higher-order interface for components with shared state, avoiding the
  2000 delicate details of mutexes and condition variables.  (Requires
  2001 Poly/ML 5.2.1 or later.)
  2002 
  2003 * ML bindings produced via Isar commands are stored within the Isar
  2004 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2005 become thread-safe and work with undo as expected (concerning
  2006 top-level bindings, not side-effects on global references).
  2007 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2008 compiler at runtime; really global bindings need to be given outside a
  2009 theory.  (Requires Poly/ML 5.2 or later.)
  2010 
  2011 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2012 context.  Top-level ML bindings are stored within the proof context in
  2013 a purely sequential fashion, disregarding the nested proof structure.
  2014 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2015 proof.  (Requires Poly/ML 5.2 or later.)
  2016 
  2017 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2018 and Method.setup, as well as Isar commands 'attribute_setup' and
  2019 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2020 existing code accordingly, or use plain 'setup' together with old
  2021 Method.add_method.
  2022 
  2023 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2024 to 'a -> thm, while results are always tagged with an authentic oracle
  2025 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2026 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2027 accordingly.  Note that extra performance may be gained by producing
  2028 the cterm carefully, avoiding slow Thm.cterm_of.
  2029 
  2030 * Simplified interface for defining document antiquotations via
  2031 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2032 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2033 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2034 examples.
  2035 
  2036 * More systematic treatment of long names, abstract name bindings, and
  2037 name space operations.  Basic operations on qualified names have been
  2038 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2039 Long_Name.append.  Old type bstring has been mostly replaced by
  2040 abstract type binding (see structure Binding), which supports precise
  2041 qualification by packages and local theory targets, as well as proper
  2042 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2043 bstring values into Binding.name, or better pass through abstract
  2044 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2045 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2046 
  2047 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2048 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2049 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2050 
  2051 * Disposed old type and term read functions (Sign.read_def_typ,
  2052 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2053 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2054 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2055 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2056 resort for legacy applications.
  2057 
  2058 * Disposed old declarations, tactics, tactic combinators that refer to
  2059 the simpset or claset of an implicit theory (such as Addsimps,
  2060 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2061 embedded ML text, or local_simpset_of with a proper context passed as
  2062 explicit runtime argument.
  2063 
  2064 * Rules and tactics that read instantiations (read_instantiate,
  2065 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2066 context, which is required for parsing and type-checking.  Moreover,
  2067 the variables are specified as plain indexnames, not string encodings
  2068 thereof.  INCOMPATIBILITY.
  2069 
  2070 * Generic Toplevel.add_hook interface allows to analyze the result of
  2071 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2072 for theorem dependency output of transactions resulting in a new
  2073 theory state.
  2074 
  2075 * ML antiquotations: block-structured compilation context indicated by
  2076 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2077 
  2078   @{binding name}                         - basic name binding
  2079   @{let ?pat = term}                      - term abbreviation (HO matching)
  2080   @{note name = fact}                     - fact abbreviation
  2081   @{thm fact}                             - singleton fact (with attributes)
  2082   @{thms fact}                            - general fact (with attributes)
  2083   @{lemma prop by method}                 - singleton goal
  2084   @{lemma prop by meth1 meth2}            - singleton goal
  2085   @{lemma prop1 ... propN by method}      - general goal
  2086   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2087   @{lemma (open) ...}                     - open derivation
  2088 
  2089 
  2090 *** System ***
  2091 
  2092 * The Isabelle "emacs" tool provides a specific interface to invoke
  2093 Proof General / Emacs, with more explicit failure if that is not
  2094 installed (the old isabelle-interface script silently falls back on
  2095 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2096 installation location of the Proof General distribution.
  2097 
  2098 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2099 the Isabelle process into a JVM/Scala application.  See
  2100 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2101 process wrapper has been discontinued.)
  2102 
  2103 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2104 
  2105 * Various status messages (with exact source position information) are
  2106 emitted, if proper markup print mode is enabled.  This allows
  2107 user-interface components to provide detailed feedback on internal
  2108 prover operations.
  2109 
  2110 
  2111 
  2112 New in Isabelle2008 (June 2008)
  2113 -------------------------------
  2114 
  2115 *** General ***
  2116 
  2117 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2118 and updated, with formally checked references as hyperlinks.
  2119 
  2120 * Theory loader: use_thy (and similar operations) no longer set the
  2121 implicit ML context, which was occasionally hard to predict and in
  2122 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2123 provides a proper context already.
  2124 
  2125 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2126 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2127 'use' within a theory file will do the job.
  2128 
  2129 * Name space merge now observes canonical order, i.e. the second space
  2130 is inserted into the first one, while existing entries in the first
  2131 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2132 swap theory imports.
  2133 
  2134 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2135 INCOMPATIBILITY in identifier syntax etc.
  2136 
  2137 * Outer syntax: string tokens no longer admit escaped white space,
  2138 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2139 white space without escapes.
  2140 
  2141 * Outer syntax: string tokens may contain arbitrary character codes
  2142 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2143 "foo_bar".
  2144 
  2145 
  2146 *** Pure ***
  2147 
  2148 * Context-dependent token translations.  Default setup reverts locally
  2149 fixed variables, and adds hilite markup for undeclared frees.
  2150 
  2151 * Unused theorems can be found using the new command 'unused_thms'.
  2152 There are three ways of invoking it:
  2153 
  2154 (1) unused_thms
  2155      Only finds unused theorems in the current theory.
  2156 
  2157 (2) unused_thms thy_1 ... thy_n -
  2158      Finds unused theorems in the current theory and all of its ancestors,
  2159      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2160 
  2161 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2162      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2163      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2164      their ancestors.
  2165 
  2166 In order to increase the readability of the list produced by
  2167 unused_thms, theorems that have been created by a particular instance
  2168 of a theory command such as 'inductive' or 'function' are considered
  2169 to belong to the same "group", meaning that if at least one theorem in
  2170 this group is used, the other theorems in the same group are no longer
  2171 reported as unused.  Moreover, if all theorems in the group are
  2172 unused, only one theorem in the group is displayed.
  2173 
  2174 Note that proof objects have to be switched on in order for
  2175 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2176 usually the case when using Proof General with the default settings).
  2177 
  2178 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2179 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2180 duplicate fact bindings, or even accidental fact duplications.  Note
  2181 that tools may maintain dynamically scoped facts systematically, using
  2182 PureThy.add_thms_dynamic.
  2183 
  2184 * Command 'hide' now allows to hide from "fact" name space as well.
  2185 
  2186 * Eliminated destructive theorem database, simpset, claset, and
  2187 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2188 update of theories within ML code.
  2189 
  2190 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2191 INCOMPATIBILITY, object-logics depending on former Pure require
  2192 additional setup PureThy.old_appl_syntax_setup; object-logics
  2193 depending on former CPure need to refer to Pure.
  2194 
  2195 * Commands 'use' and 'ML' are now purely functional, operating on
  2196 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2197 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2198 INCOMPATIBILITY.
  2199 
  2200 * Command 'setup': discontinued implicit version with ML reference.
  2201 
  2202 * Instantiation target allows for simultaneous specification of class
  2203 instance operations together with an instantiation proof.
  2204 Type-checking phase allows to refer to class operations uniformly.
  2205 See src/HOL/Complex/Complex.thy for an Isar example and
  2206 src/HOL/Library/Eval.thy for an ML example.
  2207 
  2208 * Indexing of literal facts: be more serious about including only
  2209 facts from the visible specification/proof context, but not the
  2210 background context (locale etc.).  Affects `prop` notation and method
  2211 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2212 situations.
  2213 
  2214 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2215 "(open)" option, which used to expose internal bound variables to the
  2216 proof text.
  2217 
  2218 * Isar statements: removed obsolete case "rule_context".
  2219 INCOMPATIBILITY, better use explicit fixes/assumes.
  2220 
  2221 * Locale proofs: default proof step now includes 'unfold_locales';
  2222 hence 'proof' without argument may be used to unfold locale
  2223 predicates.
  2224 
  2225 
  2226 *** Document preparation ***
  2227 
  2228 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2229 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2230 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2231 spot); renamed link color from "darkblue" to "linkcolor" (default
  2232 value unchanged, can be redefined via \definecolor); no longer sets
  2233 "a4paper" option (unnecessary or even intrusive).
  2234 
  2235 * Antiquotation @{lemma A method} proves proposition A by the given
  2236 method (either a method name or a method name plus (optional) method
  2237 arguments in parentheses) and prints A just like @{prop A}.
  2238 
  2239 
  2240 *** HOL ***
  2241 
  2242 * New primrec package.  Specification syntax conforms in style to
  2243 definition/function/....  No separate induction rule is provided.  The
  2244 "primrec" command distinguishes old-style and new-style specifications
  2245 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2246 When adjusting theories, beware: constants stemming from new-style
  2247 primrec specifications have authentic syntax.
  2248 
  2249 * Metis prover is now an order of magnitude faster, and also works
  2250 with multithreading.
  2251 
  2252 * Metis: the maximum number of clauses that can be produced from a
  2253 theorem is now given by the attribute max_clauses.  Theorems that
  2254 exceed this number are ignored, with a warning printed.
  2255 
  2256 * Sledgehammer no longer produces structured proofs by default. To
  2257 enable, declare [[sledgehammer_full = true]].  Attributes
  2258 reconstruction_modulus, reconstruction_sorts renamed
  2259 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2260 
  2261 * Method "induct_scheme" derives user-specified induction rules
  2262 from well-founded induction and completeness of patterns. This factors
  2263 out some operations that are done internally by the function package
  2264 and makes them available separately.  See
  2265 src/HOL/ex/Induction_Scheme.thy for examples.
  2266 
  2267 * More flexible generation of measure functions for termination
  2268 proofs: Measure functions can be declared by proving a rule of the
  2269 form "is_measure f" and giving it the [measure_function] attribute.
  2270 The "is_measure" predicate is logically meaningless (always true), and
  2271 just guides the heuristic.  To find suitable measure functions, the
  2272 termination prover sets up the goal "is_measure ?f" of the appropriate
  2273 type and generates all solutions by prolog-style backwards proof using
  2274 the declared rules.
  2275 
  2276 This setup also deals with rules like 
  2277 
  2278   "is_measure f ==> is_measure (list_size f)"
  2279 
  2280 which accommodates nested datatypes that recurse through lists.
  2281 Similar rules are predeclared for products and option types.
  2282 
  2283 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2284 
  2285   INCOMPATIBILITIES:
  2286 
  2287   - Definitions of overloaded constants on sets have to be replaced by
  2288     definitions on => and bool.
  2289 
  2290   - Some definitions of overloaded operators on sets can now be proved
  2291     using the definitions of the operators on => and bool.  Therefore,
  2292     the following theorems have been renamed:
  2293 
  2294       subset_def   -> subset_eq
  2295       psubset_def  -> psubset_eq
  2296       set_diff_def -> set_diff_eq
  2297       Compl_def    -> Compl_eq
  2298       Sup_set_def  -> Sup_set_eq
  2299       Inf_set_def  -> Inf_set_eq
  2300       sup_set_def  -> sup_set_eq
  2301       inf_set_def  -> inf_set_eq
  2302 
  2303   - Due to the incompleteness of the HO unification algorithm, some
  2304     rules such as subst may require manual instantiation, if some of
  2305     the unknowns in the rule is a set.
  2306 
  2307   - Higher order unification and forward proofs:
  2308     The proof pattern
  2309 
  2310       have "P (S::'a set)" <...>
  2311       then have "EX S. P S" ..
  2312 
  2313     no longer works (due to the incompleteness of the HO unification
  2314     algorithm) and must be replaced by the pattern
  2315 
  2316       have "EX S. P S"
  2317       proof
  2318         show "P S" <...>
  2319       qed
  2320 
  2321   - Calculational reasoning with subst (or similar rules):
  2322     The proof pattern
  2323 
  2324       have "P (S::'a set)" <...>
  2325       also have "S = T" <...>
  2326       finally have "P T" .
  2327 
  2328     no longer works (for similar reasons as the previous example) and
  2329     must be replaced by something like
  2330 
  2331       have "P (S::'a set)" <...>
  2332       moreover have "S = T" <...>
  2333       ultimately have "P T" by simp
  2334 
  2335   - Tactics or packages written in ML code:
  2336     Code performing pattern matching on types via
  2337 
  2338       Type ("set", [T]) => ...
  2339 
  2340     must be rewritten. Moreover, functions like strip_type or
  2341     binder_types no longer return the right value when applied to a
  2342     type of the form
  2343 
  2344       T1 => ... => Tn => U => bool
  2345 
  2346     rather than
  2347 
  2348       T1 => ... => Tn => U set
  2349 
  2350 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2351 Wellfounded_Relations to theory Wellfounded.
  2352 
  2353 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2354 
  2355 * Class finite no longer treats UNIV as class parameter.  Use class
  2356 enum from theory Library/Enum instead to achieve a similar effect.
  2357 INCOMPATIBILITY.
  2358 
  2359 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2360 and "Cons".  INCOMPATIBILITY.
  2361 
  2362 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2363 Potential INCOMPATIBILITY.
  2364 
  2365 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2366 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2367 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2368 
  2369 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2370 the same name in theory Orderings:
  2371 
  2372   less_trans
  2373   less_linear
  2374   le_imp_less_or_eq
  2375   le_less_trans
  2376   less_le_trans
  2377   less_not_sym
  2378   less_asym
  2379 
  2380 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2381 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2382 and different variable names.
  2383 
  2384 * Library/Option_ord.thy: Canonical order on option type.
  2385 
  2386 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2387 finite maps.
  2388 
  2389 * Library/Countable.thy: Type class for countable types.
  2390 
  2391 * Theory Int: The representation of numerals has changed.  The infix
  2392 operator BIT and the bit datatype with constructors B0 and B1 have
  2393 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2394 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2395 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2396 accordingly.
  2397 
  2398 * Theory Nat: definition of <= and < on natural numbers no longer
  2399 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2400 le_def and less_def have disappeared.  Consider lemmas not_less
  2401 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2402 
  2403 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2404 (whose purpose mainly is for various fold_set functionals) have been
  2405 abandoned in favor of the existing algebraic classes
  2406 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2407 lower_semilattice (resp. upper_semilattice) and linorder.
  2408 INCOMPATIBILITY.
  2409 
  2410 * Theory Transitive_Closure: induct and cases rules now declare proper
  2411 case_names ("base" and "step").  INCOMPATIBILITY.
  2412 
  2413 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2414 lattices.  The form set-specific version is available as
  2415 Inductive.lfp_ordinal_induct_set.
  2416 
  2417 * Renamed theorems "power.simps" to "power_int.simps".
  2418 INCOMPATIBILITY.
  2419 
  2420 * Class semiring_div provides basic abstract properties of semirings
  2421 with division and modulo operations.  Subsumes former class dvd_mod.
  2422 
  2423 * Merged theories IntDef, Numeral and IntArith into unified theory
  2424 Int.  INCOMPATIBILITY.
  2425 
  2426 * Theory Library/Code_Index: type "index" now represents natural
  2427 numbers rather than integers.  INCOMPATIBILITY.
  2428 
  2429 * New class "uminus" with operation "uminus" (split of from class
  2430 "minus" which now only has operation "minus", binary).
  2431 INCOMPATIBILITY.
  2432 
  2433 * Constants "card", "internal_split", "option_map" now with authentic
  2434 syntax.  INCOMPATIBILITY.
  2435 
  2436 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2437 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2438 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2439 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2440 Sup_set_def, le_def, less_def, option_map_def now with object
  2441 equality.  INCOMPATIBILITY.
  2442 
  2443 * Records. Removed K_record, and replaced it by pure lambda term
  2444 %x. c. The simplifier setup is now more robust against eta expansion.
  2445 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2446 
  2447 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2448 
  2449 * Library/ListVector: new theory of arithmetic vector operations.
  2450 
  2451 * Library/Order_Relation: new theory of various orderings as sets of
  2452 pairs.  Defines preorders, partial orders, linear orders and
  2453 well-orders on sets and on types.
  2454 
  2455 
  2456 *** ZF ***
  2457 
  2458 * Renamed some theories to allow to loading both ZF and HOL in the
  2459 same session:
  2460 
  2461   Datatype  -> Datatype_ZF
  2462   Inductive -> Inductive_ZF
  2463   Int       -> Int_ZF
  2464   IntDiv    -> IntDiv_ZF
  2465   Nat       -> Nat_ZF
  2466   List      -> List_ZF
  2467   Main      -> Main_ZF
  2468 
  2469 INCOMPATIBILITY: ZF theories that import individual theories below
  2470 Main might need to be adapted.  Regular theory Main is still
  2471 available, as trivial extension of Main_ZF.
  2472 
  2473 
  2474 *** ML ***
  2475 
  2476 * ML within Isar: antiquotation @{const name} or @{const
  2477 name(typargs)} produces statically-checked Const term.
  2478 
  2479 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2480 (of the same name).  Removed obsolete print command.
  2481 
  2482 * Removed obsolete "use_legacy_bindings" function.
  2483 
  2484 * The ``print mode'' is now a thread-local value derived from a global
  2485 template (the former print_mode reference), thus access becomes
  2486 non-critical.  The global print_mode reference is for session
  2487 management only; user-code should use print_mode_value,
  2488 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2489 
  2490 * Functions system/system_out provide a robust way to invoke external
  2491 shell commands, with propagation of interrupts (requires Poly/ML
  2492 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2493 
  2494 
  2495 *** System ***
  2496 
  2497 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2498 in accordance with Proof General 3.7, which prefers GNU emacs.
  2499 
  2500 * isatool tty runs Isabelle process with plain tty interaction;
  2501 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2502 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2503 
  2504 * isatool browser now works with Cygwin as well, using general
  2505 "javapath" function defined in Isabelle process environment.
  2506 
  2507 * YXML notation provides a simple and efficient alternative to
  2508 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2509 isatool yxml as described in the Isabelle system manual.
  2510 
  2511 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2512 provides general wrapper for managing an Isabelle process in a robust
  2513 fashion, with ``cooked'' output from stdin/stderr.
  2514 
  2515 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2516 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2517 
  2518 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2519 way of changing the user's settings is via
  2520 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2521 script.
  2522 
  2523 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2524 cores of the underlying machine, which is a good starting point for
  2525 optimal performance tuning.  The corresponding usedir option -M allows
  2526 "max" as an alias for "0".  WARNING: does not work on certain versions
  2527 of Mac OS (with Poly/ML 5.1).
  2528 
  2529 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2530 adverse effect of Isabelle flooding interactive front-ends (notably
  2531 ProofGeneral / XEmacs).
  2532 
  2533 
  2534 
  2535 New in Isabelle2007 (November 2007)
  2536 -----------------------------------
  2537 
  2538 *** General ***
  2539 
  2540 * More uniform information about legacy features, notably a
  2541 warning/error of "Legacy feature: ...", depending on the state of the
  2542 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2543 legacy features will disappear eventually.
  2544 
  2545 * Theory syntax: the header format ``theory A = B + C:'' has been
  2546 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2547 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2548 
  2549 * Theory syntax: the old non-Isar theory file format has been
  2550 discontinued altogether.  Note that ML proof scripts may still be used
  2551 with Isar theories; migration is usually quite simple with the ML
  2552 function use_legacy_bindings.  INCOMPATIBILITY.
  2553 
  2554 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2555 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2556 quotes.
  2557 
  2558 * Theory loader: be more serious about observing the static theory
  2559 header specifications (including optional directories), but not the
  2560 accidental file locations of previously successful loads.  The strict
  2561 update policy of former update_thy is now already performed by
  2562 use_thy, so the former has been removed; use_thys updates several
  2563 theories simultaneously, just as 'imports' within a theory header
  2564 specification, but without merging the results.  Potential
  2565 INCOMPATIBILITY: may need to refine theory headers and commands
  2566 ROOT.ML which depend on load order.
  2567 
  2568 * Theory loader: optional support for content-based file
  2569 identification, instead of the traditional scheme of full physical
  2570 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2571 (cf. the system manual).  The new scheme allows to work with
  2572 non-finished theories in persistent session images, such that source
  2573 files may be moved later on without requiring reloads.
  2574 
  2575 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2576 file (with the same base name as the theory) are considered a legacy
  2577 feature, which will disappear eventually. Even now, the theory loader
  2578 no longer maintains dependencies on such files.
  2579 
  2580 * Syntax: the scope for resolving ambiguities via type-inference is
  2581 now limited to individual terms, instead of whole simultaneous
  2582 specifications as before. This greatly reduces the complexity of the
  2583 syntax module and improves flexibility by separating parsing and
  2584 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2585 'fixes' etc.) are required in rare situations.
  2586 
  2587 * Syntax: constants introduced by new-style packages ('definition',
  2588 'abbreviation' etc.) are passed through the syntax module in
  2589 ``authentic mode''. This means that associated mixfix annotations
  2590 really stick to such constants, independently of potential name space
  2591 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2592 trees are represented slightly differently, may need to adapt syntax
  2593 translations accordingly. Use CONST marker in 'translations' and
  2594 @{const_syntax} antiquotation in 'parse_translation' etc.
  2595 
  2596 * Legacy goal package: reduced interface to the bare minimum required
  2597 to keep existing proof scripts running.  Most other user-level
  2598 functions are now part of the OldGoals structure, which is *not* open
  2599 by default (consider isatool expandshort before open OldGoals).
  2600 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2601 these tend to cause confusion about the actual goal (!) context being
  2602 used here, which is not necessarily the same as the_context().
  2603 
  2604 * Command 'find_theorems': supports "*" wild-card in "name:"
  2605 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2606 support a specific search form (see ProofGeneral/CHANGES).
  2607 
  2608 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2609 by default, which means that "prems" (and also "fixed variables") are
  2610 suppressed from proof state output.  Note that the ProofGeneral
  2611 settings mechanism allows to change and save options persistently, but
  2612 older versions of Isabelle will fail to start up if a negative prems
  2613 limit is imposed.
  2614 
  2615 * Local theory targets may be specified by non-nested blocks of
  2616 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2617 contain definitions, theorems etc., including any derived mechanism
  2618 that has been implemented on top of these primitives.  This concept
  2619 generalizes the existing ``theorem (in ...)'' towards more versatility
  2620 and scalability.
  2621 
  2622 * Proof General interface: proper undo of final 'end' command;
  2623 discontinued Isabelle/classic mode (ML proof scripts).
  2624 
  2625 
  2626 *** Document preparation ***
  2627 
  2628 * Added antiquotation @{theory name} which prints the given name,
  2629 after checking that it refers to a valid ancestor theory in the
  2630 current context.
  2631 
  2632 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2633 check the given source text as ML type/structure, printing verbatim.
  2634 
  2635 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2636 "c args == rhs" given in the current context.  (Any number of
  2637 arguments may be given on the LHS.)
  2638 
  2639 
  2640 *** Pure ***
  2641 
  2642 * The 'class' package offers a combination of axclass and locale to
  2643 achieve Haskell-like type classes in Isabelle.  Definitions and
  2644 theorems within a class context produce both relative results (with
  2645 implicit parameters according to the locale context), and polymorphic
  2646 constants with qualified polymorphism (according to the class
  2647 context).  Within the body context of a 'class' target, a separate
  2648 syntax layer ("user space type system") takes care of converting
  2649 between global polymorphic consts and internal locale representation.
  2650 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2651 "isatool doc classes" provides a tutorial.
  2652 
  2653 * Generic code generator framework allows to generate executable
  2654 code for ML and Haskell (including Isabelle classes).  A short usage
  2655 sketch:
  2656 
  2657     internal compilation:
  2658         export_code <list of constants (term syntax)> in SML
  2659     writing SML code to a file:
  2660         export_code <list of constants (term syntax)> in SML <filename>
  2661     writing OCaml code to a file:
  2662         export_code <list of constants (term syntax)> in OCaml <filename>
  2663     writing Haskell code to a bunch of files:
  2664         export_code <list of constants (term syntax)> in Haskell <filename>
  2665 
  2666     evaluating closed propositions to True/False using code generation:
  2667         method ``eval''
  2668 
  2669 Reasonable default setup of framework in HOL.
  2670 
  2671 Theorem attributs for selecting and transforming function equations theorems:
  2672 
  2673     [code fun]:        select a theorem as function equation for a specific constant
  2674     [code fun del]:    deselect a theorem as function equation for a specific constant
  2675     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2676     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2677 
  2678 User-defined serializations (target in {SML, OCaml, Haskell}):
  2679 
  2680     code_const <and-list of constants (term syntax)>
  2681       {(target) <and-list of const target syntax>}+
  2682 
  2683     code_type <and-list of type constructors>
  2684       {(target) <and-list of type target syntax>}+
  2685 
  2686     code_instance <and-list of instances>
  2687       {(target)}+
  2688         where instance ::= <type constructor> :: <class>
  2689 
  2690     code_class <and_list of classes>
  2691       {(target) <and-list of class target syntax>}+
  2692         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2693 
  2694 code_instance and code_class only are effective to target Haskell.
  2695 
  2696 For example usage see src/HOL/ex/Codegenerator.thy and
  2697 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2698 generation from Isabelle/HOL theories is available via "isatool doc
  2699 codegen".
  2700 
  2701 * Code generator: consts in 'consts_code' Isar commands are now
  2702 referred to by usual term syntax (including optional type
  2703 annotations).
  2704 
  2705 * Command 'no_translations' removes translation rules from theory
  2706 syntax.
  2707 
  2708 * Overloaded definitions are now actually checked for acyclic
  2709 dependencies.  The overloading scheme is slightly more general than
  2710 that of Haskell98, although Isabelle does not demand an exact
  2711 correspondence to type class and instance declarations.
  2712 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2713 exotic versions of overloading -- at the discretion of the user!
  2714 
  2715 Polymorphic constants are represented via type arguments, i.e. the
  2716 instantiation that matches an instance against the most general
  2717 declaration given in the signature.  For example, with the declaration
  2718 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2719 as c(nat).  Overloading is essentially simultaneous structural
  2720 recursion over such type arguments.  Incomplete specification patterns
  2721 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2722 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2723 Command 'print_theory' outputs the normalized system of recursive
  2724 equations, see section "definitions".
  2725 
  2726 * Configuration options are maintained within the theory or proof
  2727 context (with name and type bool/int/string), providing a very simple
  2728 interface to a poor-man's version of general context data.  Tools may
  2729 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2730 these values using Config.get etc.  Users may change options via an
  2731 associated attribute of the same name.  This form of context
  2732 declaration works particularly well with commands 'declare' or
  2733 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2734 very easy to avoid global references, which would not observe Isar
  2735 toplevel undo/redo and fail to work with multithreading.
  2736 
  2737 Various global ML references of Pure and HOL have been turned into
  2738 configuration options:
  2739 
  2740   Unify.search_bound		unify_search_bound
  2741   Unify.trace_bound		unify_trace_bound
  2742   Unify.trace_simp		unify_trace_simp
  2743   Unify.trace_types		unify_trace_types
  2744   Simplifier.simp_depth_limit	simp_depth_limit
  2745   Blast.depth_limit		blast_depth_limit
  2746   DatatypeProp.dtK		datatype_distinctness_limit
  2747   fast_arith_neq_limit  	fast_arith_neq_limit
  2748   fast_arith_split_limit	fast_arith_split_limit
  2749 
  2750 * Named collections of theorems may be easily installed as context
  2751 data using the functor NamedThmsFun (see also
  2752 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2753 attributes; there is also a toplevel print command.  This facility is
  2754 just a common case of general context data, which is the preferred way
  2755 for anything more complex than just a list of facts in canonical
  2756 order.
  2757 
  2758 * Isar: command 'declaration' augments a local theory by generic
  2759 declaration functions written in ML.  This enables arbitrary content
  2760 being added to the context, depending on a morphism that tells the
  2761 difference of the original declaration context wrt. the application
  2762 context encountered later on.
  2763 
  2764 * Isar: proper interfaces for simplification procedures.  Command
  2765 'simproc_setup' declares named simprocs (with match patterns, and body
  2766 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2767 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2768 
  2769 * Isar: an extra pair of brackets around attribute declarations
  2770 abbreviates a theorem reference involving an internal dummy fact,
  2771 which will be ignored later --- only the effect of the attribute on
  2772 the background context will persist.  This form of in-place
  2773 declarations is particularly useful with commands like 'declare' and
  2774 'using', for example ``have A using [[simproc a]] by simp''.
  2775 
  2776 * Isar: method "assumption" (and implicit closing of subproofs) now
  2777 takes simple non-atomic goal assumptions into account: after applying
  2778 an assumption as a rule the resulting subgoals are solved by atomic
  2779 assumption steps.  This is particularly useful to finish 'obtain'
  2780 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2781 without referring to the original premise "!!x. P x ==> thesis" in the
  2782 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2783 more permissive.
  2784 
  2785 * Isar: implicit use of prems from the Isar proof context is
  2786 considered a legacy feature.  Common applications like ``have A .''
  2787 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2788 referencing facts explicitly here improves readability and
  2789 maintainability of proof texts.
  2790 
  2791 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2792 the obtained context from the course of reasoning!  For example:
  2793 
  2794   assume "EX x y. A x & B y"   -- "any previous fact"
  2795   then guess x and y by clarify
  2796 
  2797 This technique is potentially adventurous, depending on the facts and
  2798 proof tools being involved here.
  2799 
  2800 * Isar: known facts from the proof context may be specified as literal
  2801 propositions, using ASCII back-quote syntax.  This works wherever
  2802 named facts used to be allowed so far, in proof commands, proof
  2803 methods, attributes etc.  Literal facts are retrieved from the context
  2804 according to unification of type and term parameters.  For example,
  2805 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2806 theorems in the current context, then these are valid literal facts:
  2807 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2808 
  2809 There is also a proof method "fact" which does the same composition
  2810 for explicit goal states, e.g. the following proof texts coincide with
  2811 certain special cases of literal facts:
  2812 
  2813   have "A" by fact                 ==  note `A`
  2814   have "A ==> B" by fact           ==  note `A ==> B`
  2815   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2816   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2817 
  2818 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2819 outer syntax.  Thus symbolic identifiers may be used without
  2820 additional white space in declarations like this: ``assume *: A''.
  2821 
  2822 * Isar: 'print_facts' prints all local facts of the current context,
  2823 both named and unnamed ones.
  2824 
  2825 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2826 
  2827   def x == "t" and y == "u"
  2828 
  2829 * Isar: added command 'unfolding', which is structurally similar to
  2830 'using', but affects both the goal state and facts by unfolding given
  2831 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2832 'unfolded' attribute may be replaced by first-class proof text.
  2833 
  2834 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2835 and command 'unfolding' now all support object-level equalities
  2836 (potentially conditional).  The underlying notion of rewrite rule is
  2837 analogous to the 'rule_format' attribute, but *not* that of the
  2838 Simplifier (which is usually more generous).
  2839 
  2840 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2841 premises of a theorem by n. Useful in conjunction with drule.
  2842 
  2843 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2844 method expression within a sandbox consisting of the first N
  2845 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2846 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2847 simplifies all new goals that emerge from applying rule foo to the
  2848 originally first one.
  2849 
  2850 * Isar: schematic goals are no longer restricted to higher-order
  2851 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2852 expected.
  2853 
  2854 * Isar: the conclusion of a long theorem statement is now either
  2855 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2856 (essentially a disjunction of cases with local parameters and
  2857 assumptions).  The latter allows to express general elimination rules
  2858 adequately; in this notation common elimination rules look like this:
  2859 
  2860   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2861     assumes "EX x. P x"
  2862     obtains x where "P x"
  2863 
  2864   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2865     assumes "A & B"
  2866     obtains A and B
  2867 
  2868   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2869     assumes "A | B"
  2870     obtains
  2871       A
  2872     | B
  2873 
  2874 The subsequent classical rules even refer to the formal "thesis"
  2875 explicitly:
  2876 
  2877   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2878     obtains "~ thesis"
  2879 
  2880   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2881     obtains "thesis ==> something"
  2882 
  2883 The actual proof of an 'obtains' statement is analogous to that of the
  2884 Isar proof element 'obtain', only that there may be several cases.
  2885 Optional case names may be specified in parentheses; these will be
  2886 available both in the present proof and as annotations in the
  2887 resulting rule, for later use with the 'cases' method (cf. attribute
  2888 case_names).
  2889 
  2890 * Isar: the assumptions of a long theorem statement are available as
  2891 "assms" fact in the proof context.  This is more appropriate than the
  2892 (historical) "prems", which refers to all assumptions of the current
  2893 context, including those from the target locale, proof body etc.
  2894 
  2895 * Isar: 'print_statement' prints theorems from the current theory or
  2896 proof context in long statement form, according to the syntax of a
  2897 top-level lemma.
  2898 
  2899 * Isar: 'obtain' takes an optional case name for the local context
  2900 introduction rule (default "that").
  2901 
  2902 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2903 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2904 to occur.
  2905 
  2906 * Pure: syntax "CONST name" produces a fully internalized constant
  2907 according to the current context.  This is particularly useful for
  2908 syntax translations that should refer to internal constant
  2909 representations independently of name spaces.
  2910 
  2911 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2912 instead of "FOO ". This allows multiple binder declarations to coexist
  2913 in the same context.  INCOMPATIBILITY.
  2914 
  2915 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2916 primitive that also works in a locale context (both for constants and
  2917 fixed variables). Type declaration and internal syntactic representation
  2918 of given constants retrieved from the context. Likewise, the
  2919 'no_notation' command allows to remove given syntax annotations from the
  2920 current context.
  2921 
  2922 * Isar/locales: new derived specification elements 'axiomatization',
  2923 'definition', 'abbreviation', which support type-inference, admit
  2924 object-level specifications (equality, equivalence).  See also the
  2925 isar-ref manual.  Examples:
  2926 
  2927   axiomatization
  2928     eq  (infix "===" 50) where
  2929     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2930 
  2931   definition "f x y = x + y + 1"
  2932   definition g where "g x = f x x"
  2933 
  2934   abbreviation
  2935     neq  (infix "=!=" 50) where
  2936     "x =!= y == ~ (x === y)"
  2937 
  2938 These specifications may be also used in a locale context.  Then the
  2939 constants being introduced depend on certain fixed parameters, and the
  2940 constant name is qualified by the locale base name.  An internal
  2941 abbreviation takes care for convenient input and output, making the
  2942 parameters implicit and using the original short name.  See also
  2943 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2944 entities from a monomorphic theory.
  2945 
  2946 Presently, abbreviations are only available 'in' a target locale, but
  2947 not inherited by general import expressions.  Also note that
  2948 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2949 'translations' in common applications.  The "no_abbrevs" print mode
  2950 prevents folding of abbreviations in term output.
  2951 
  2952 Concrete syntax is attached to specified constants in internal form,
  2953 independently of name spaces.  The parse tree representation is
  2954 slightly different -- use 'notation' instead of raw 'syntax', and
  2955 'translations' with explicit "CONST" markup to accommodate this.
  2956 
  2957 * Pure/Isar: unified syntax for new-style specification mechanisms
  2958 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2959 full type inference and dummy patterns ("_").  For example:
  2960 
  2961   definition "K x _ = x"
  2962 
  2963   inductive conj for A B
  2964   where "A ==> B ==> conj A B"
  2965 
  2966 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2967 the current context.  Print mode "no_abbrevs" prevents inversion of
  2968 abbreviations on output.
  2969 
  2970 * Isar/locales: improved parameter handling: use of locales "var" and
  2971 "struct" no longer necessary; - parameter renamings are no longer
  2972 required to be injective.  For example, this allows to define
  2973 endomorphisms as locale endom = homom mult mult h.
  2974 
  2975 * Isar/locales: changed the way locales with predicates are defined.
  2976 Instead of accumulating the specification, the imported expression is
  2977 now an interpretation.  INCOMPATIBILITY: different normal form of
  2978 locale expressions.  In particular, in interpretations of locales with
  2979 predicates, goals repesenting already interpreted fragments are not
  2980 removed automatically.  Use methods `intro_locales' and
  2981 `unfold_locales'; see below.
  2982 
  2983 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2984 provide backward reasoning on locales predicates.  The methods are
  2985 aware of interpretations and discharge corresponding goals.
  2986 `intro_locales' is less aggressive then `unfold_locales' and does not
  2987 unfold predicates to assumptions.
  2988 
  2989 * Isar/locales: the order in which locale fragments are accumulated
  2990 has changed.  This enables to override declarations from fragments due
  2991 to interpretations -- for example, unwanted simp rules.
  2992 
  2993 * Isar/locales: interpretation in theories and proof contexts has been
  2994 extended.  One may now specify (and prove) equations, which are
  2995 unfolded in interpreted theorems.  This is useful for replacing
  2996 defined concepts (constants depending on locale parameters) by
  2997 concepts already existing in the target context.  Example:
  2998 
  2999   interpretation partial_order ["op <= :: [int, int] => bool"]
  3000     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3001 
  3002 Typically, the constant `partial_order.less' is created by a
  3003 definition specification element in the context of locale
  3004 partial_order.
  3005 
  3006 * Method "induct": improved internal context management to support
  3007 local fixes and defines on-the-fly. Thus explicit meta-level
  3008 connectives !!  and ==> are rarely required anymore in inductive goals
  3009 (using object-logic connectives for this purpose has been long
  3010 obsolete anyway). Common proof patterns are explained in
  3011 src/HOL/Induct/Common_Patterns.thy, see also
  3012 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3013 examples.
  3014 
  3015 * Method "induct": improved handling of simultaneous goals. Instead of
  3016 introducing object-level conjunction, the statement is now split into
  3017 several conclusions, while the corresponding symbolic cases are nested
  3018 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3019 see src/HOL/Induct/Common_Patterns.thy, for example.
  3020 
  3021 * Method "induct": mutual induction rules are now specified as a list
  3022 of rule sharing the same induction cases. HOL packages usually provide
  3023 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3024 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3025 mutual induction rules differently, i.e. like this:
  3026 
  3027   (induct rule: foo_bar.inducts)
  3028   (induct set: foo bar)
  3029   (induct pred: foo bar)
  3030   (induct type: foo bar)
  3031 
  3032 The ML function ProjectRule.projections turns old-style rules into the
  3033 new format.
  3034 
  3035 * Method "coinduct": dual of induction, see
  3036 src/HOL/Library/Coinductive_List.thy for various examples.
  3037 
  3038 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3039 considered a legacy feature.
  3040 
  3041 * Attribute "symmetric" produces result with standardized schematic
  3042 variables (index 0).  Potential INCOMPATIBILITY.
  3043 
  3044 * Simplifier: by default the simplifier trace only shows top level
  3045 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3046 default. Thus there is less danger of being flooded by the trace. The
  3047 trace indicates where parts have been suppressed.
  3048   
  3049 * Provers/classical: removed obsolete classical version of elim_format
  3050 attribute; classical elim/dest rules are now treated uniformly when
  3051 manipulating the claset.
  3052 
  3053 * Provers/classical: stricter checks to ensure that supplied intro,
  3054 dest and elim rules are well-formed; dest and elim rules must have at
  3055 least one premise.
  3056 
  3057 * Provers/classical: attributes dest/elim/intro take an optional
  3058 weight argument for the rule (just as the Pure versions).  Weights are
  3059 ignored by automated tools, but determine the search order of single
  3060 rule steps.
  3061 
  3062 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3063 where the body does not mention the bound variable.  Note that dummy
  3064 patterns implicitly depend on their context of bounds, which makes
  3065 "{_. _}" match any set comprehension as expected.  Potential
  3066 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3067 constant "_idtdummy" in the binding position.
  3068 
  3069 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3070 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3071 for example "A -> B" => "Pi A (%_. B)".
  3072 
  3073 * Pure: 'class_deps' command visualizes the subclass relation, using
  3074 the graph browser tool.
  3075 
  3076 * Pure: 'print_theory' now suppresses certain internal declarations by
  3077 default; use '!' option for full details.
  3078 
  3079 
  3080 *** HOL ***
  3081 
  3082 * Method "metis" proves goals by applying the Metis general-purpose
  3083 resolution prover (see also http://gilith.com/software/metis/).
  3084 Examples are in the directory MetisExamples.  WARNING: the
  3085 Isabelle/HOL-Metis integration does not yet work properly with
  3086 multi-threading.
  3087   
  3088 * Command 'sledgehammer' invokes external automatic theorem provers as
  3089 background processes.  It generates calls to the "metis" method if
  3090 successful. These can be pasted into the proof.  Users do not have to
  3091 wait for the automatic provers to return.  WARNING: does not really
  3092 work with multi-threading.
  3093 
  3094 * New "auto_quickcheck" feature tests outermost goal statements for
  3095 potential counter-examples.  Controlled by ML references
  3096 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3097 5000 milliseconds).  Fails silently if statements is outside of
  3098 executable fragment, or any other codgenerator problem occurs.
  3099 
  3100 * New constant "undefined" with axiom "undefined x = undefined".
  3101 
  3102 * Added class "HOL.eq", allowing for code generation with polymorphic
  3103 equality.
  3104 
  3105 * Some renaming of class constants due to canonical name prefixing in
  3106 the new 'class' package:
  3107 
  3108     HOL.abs ~> HOL.abs_class.abs
  3109     HOL.divide ~> HOL.divide_class.divide
  3110     0 ~> HOL.zero_class.zero
  3111     1 ~> HOL.one_class.one
  3112     op + ~> HOL.plus_class.plus
  3113     op - ~> HOL.minus_class.minus
  3114     uminus ~> HOL.minus_class.uminus
  3115     op * ~> HOL.times_class.times
  3116     op < ~> HOL.ord_class.less
  3117     op <= > HOL.ord_class.less_eq
  3118     Nat.power ~> Power.power_class.power
  3119     Nat.size ~> Nat.size_class.size
  3120     Numeral.number_of ~> Numeral.number_class.number_of
  3121     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3122     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3123     Orderings.min ~> Orderings.ord_class.min
  3124     Orderings.max ~> Orderings.ord_class.max
  3125     Divides.op div ~> Divides.div_class.div
  3126     Divides.op mod ~> Divides.div_class.mod
  3127     Divides.op dvd ~> Divides.div_class.dvd
  3128 
  3129 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3130 
  3131 a) User-defined constants using any of the names "plus", "minus",
  3132 "times", "less" or "less_eq". The standard syntax translations for
  3133 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3134 names.
  3135 
  3136 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3137 INCOMPATIBILITY: use more specific names.
  3138 
  3139 c) Permutative equations (e.g. "a + b = b + a")
  3140 Since the change of names also changes the order of terms, permutative
  3141 rewrite rules may get applied in a different order. Experience shows
  3142 that this is rarely the case (only two adaptions in the whole Isabelle
  3143 distribution).  INCOMPATIBILITY: rewrite proofs
  3144 
  3145 d) ML code directly refering to constant names
  3146 This in general only affects hand-written proof tactics, simprocs and
  3147 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3148 Consider using @{const_name} antiquotation.
  3149 
  3150 * New class "default" with associated constant "default".
  3151 
  3152 * Function "sgn" is now overloaded and available on int, real, complex
  3153 (and other numeric types), using class "sgn".  Two possible defs of
  3154 sgn are given as equational assumptions in the classes sgn_if and
  3155 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3156 INCOMPATIBILITY.
  3157 
  3158 * Locale "partial_order" now unified with class "order" (cf. theory
  3159 Orderings), added parameter "less".  INCOMPATIBILITY.
  3160 
  3161 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3162 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3163 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3164 
  3165 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3166 changed order of proof goals in instance proofs.
  3167 
  3168 * The transitivity reasoner for partial and linear orders is set up
  3169 for classes "order" and "linorder".  Instances of the reasoner are available
  3170 in all contexts importing or interpreting the corresponding locales.
  3171 Method "order" invokes the reasoner separately; the reasoner
  3172 is also integrated with the Simplifier as a solver.  Diagnostic
  3173 command 'print_orders' shows the available instances of the reasoner
  3174 in the current context.
  3175 
  3176 * Localized monotonicity predicate in theory "Orderings"; integrated
  3177 lemmas max_of_mono and min_of_mono with this predicate.
  3178 INCOMPATIBILITY.
  3179 
  3180 * Formulation of theorem "dense" changed slightly due to integration
  3181 with new class dense_linear_order.
  3182 
  3183 * Uniform lattice theory development in HOL.
  3184 
  3185     constants "meet" and "join" now named "inf" and "sup"
  3186     constant "Meet" now named "Inf"
  3187 
  3188     classes "meet_semilorder" and "join_semilorder" now named
  3189       "lower_semilattice" and "upper_semilattice"
  3190     class "lorder" now named "lattice"
  3191     class "comp_lat" now named "complete_lattice"
  3192 
  3193     Instantiation of lattice classes allows explicit definitions
  3194     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3195 
  3196   INCOMPATIBILITY.  Theorem renames:
  3197 
  3198     meet_left_le            ~> inf_le1
  3199     meet_right_le           ~> inf_le2
  3200     join_left_le            ~> sup_ge1
  3201     join_right_le           ~> sup_ge2
  3202     meet_join_le            ~> inf_sup_ord
  3203     le_meetI                ~> le_infI
  3204     join_leI                ~> le_supI
  3205     le_meet                 ~> le_inf_iff
  3206     le_join                 ~> ge_sup_conv
  3207     meet_idempotent         ~> inf_idem
  3208     join_idempotent         ~> sup_idem
  3209     meet_comm               ~> inf_commute
  3210     join_comm               ~> sup_commute
  3211     meet_leI1               ~> le_infI1
  3212     meet_leI2               ~> le_infI2
  3213     le_joinI1               ~> le_supI1
  3214     le_joinI2               ~> le_supI2
  3215     meet_assoc              ~> inf_assoc
  3216     join_assoc              ~> sup_assoc
  3217     meet_left_comm          ~> inf_left_commute
  3218     meet_left_idempotent    ~> inf_left_idem
  3219     join_left_comm          ~> sup_left_commute
  3220     join_left_idempotent    ~> sup_left_idem
  3221     meet_aci                ~> inf_aci
  3222     join_aci                ~> sup_aci
  3223     le_def_meet             ~> le_iff_inf
  3224     le_def_join             ~> le_iff_sup
  3225     join_absorp2            ~> sup_absorb2
  3226     join_absorp1            ~> sup_absorb1
  3227     meet_absorp1            ~> inf_absorb1
  3228     meet_absorp2            ~> inf_absorb2
  3229     meet_join_absorp        ~> inf_sup_absorb
  3230     join_meet_absorp        ~> sup_inf_absorb
  3231     distrib_join_le         ~> distrib_sup_le
  3232     distrib_meet_le         ~> distrib_inf_le
  3233 
  3234     add_meet_distrib_left   ~> add_inf_distrib_left
  3235     add_join_distrib_left   ~> add_sup_distrib_left
  3236     is_join_neg_meet        ~> is_join_neg_inf
  3237     is_meet_neg_join        ~> is_meet_neg_sup
  3238     add_meet_distrib_right  ~> add_inf_distrib_right
  3239     add_join_distrib_right  ~> add_sup_distrib_right
  3240     add_meet_join_distribs  ~> add_sup_inf_distribs
  3241     join_eq_neg_meet        ~> sup_eq_neg_inf
  3242     meet_eq_neg_join        ~> inf_eq_neg_sup
  3243     add_eq_meet_join        ~> add_eq_inf_sup
  3244     meet_0_imp_0            ~> inf_0_imp_0
  3245     join_0_imp_0            ~> sup_0_imp_0
  3246     meet_0_eq_0             ~> inf_0_eq_0
  3247     join_0_eq_0             ~> sup_0_eq_0
  3248     neg_meet_eq_join        ~> neg_inf_eq_sup
  3249     neg_join_eq_meet        ~> neg_sup_eq_inf
  3250     join_eq_if              ~> sup_eq_if
  3251 
  3252     mono_meet               ~> mono_inf
  3253     mono_join               ~> mono_sup
  3254     meet_bool_eq            ~> inf_bool_eq
  3255     join_bool_eq            ~> sup_bool_eq
  3256     meet_fun_eq             ~> inf_fun_eq
  3257     join_fun_eq             ~> sup_fun_eq
  3258     meet_set_eq             ~> inf_set_eq
  3259     join_set_eq             ~> sup_set_eq
  3260     meet1_iff               ~> inf1_iff
  3261     meet2_iff               ~> inf2_iff
  3262     meet1I                  ~> inf1I
  3263     meet2I                  ~> inf2I
  3264     meet1D1                 ~> inf1D1
  3265     meet2D1                 ~> inf2D1
  3266     meet1D2                 ~> inf1D2
  3267     meet2D2                 ~> inf2D2
  3268     meet1E                  ~> inf1E
  3269     meet2E                  ~> inf2E
  3270     join1_iff               ~> sup1_iff
  3271     join2_iff               ~> sup2_iff
  3272     join1I1                 ~> sup1I1
  3273     join2I1                 ~> sup2I1
  3274     join1I1                 ~> sup1I1
  3275     join2I2                 ~> sup1I2
  3276     join1CI                 ~> sup1CI
  3277     join2CI                 ~> sup2CI
  3278     join1E                  ~> sup1E
  3279     join2E                  ~> sup2E
  3280 
  3281     is_meet_Meet            ~> is_meet_Inf
  3282     Meet_bool_def           ~> Inf_bool_def
  3283     Meet_fun_def            ~> Inf_fun_def
  3284     Meet_greatest           ~> Inf_greatest
  3285     Meet_lower              ~> Inf_lower
  3286     Meet_set_def            ~> Inf_set_def
  3287 
  3288     Sup_def                 ~> Sup_Inf
  3289     Sup_bool_eq             ~> Sup_bool_def
  3290     Sup_fun_eq              ~> Sup_fun_def
  3291     Sup_set_eq              ~> Sup_set_def
  3292 
  3293     listsp_meetI            ~> listsp_infI
  3294     listsp_meet_eq          ~> listsp_inf_eq
  3295 
  3296     meet_min                ~> inf_min
  3297     join_max                ~> sup_max
  3298 
  3299 * Added syntactic class "size"; overloaded constant "size" now has
  3300 type "'a::size ==> bool"
  3301 
  3302 * Internal reorganisation of `size' of datatypes: size theorems
  3303 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3304 simplification rules by default!); theorems "prod.size" now named
  3305 "*.size".
  3306 
  3307 * Class "div" now inherits from class "times" rather than "type".
  3308 INCOMPATIBILITY.
  3309 
  3310 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3311 Linorder etc.  have disappeared; operations defined in terms of
  3312 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3313 
  3314 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3315 
  3316 * HOL-Word: New extensive library and type for generic, fixed size
  3317 machine words, with arithemtic, bit-wise, shifting and rotating
  3318 operations, reflection into int, nat, and bool lists, automation for
  3319 linear arithmetic (by automatic reflection into nat or int), including
  3320 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3321 arithmetic type classes, supporting automatic simplification of
  3322 numerals on all operations.
  3323 
  3324 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3325 
  3326 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3327 
  3328 * Code generator library theories:
  3329   - Code_Integer represents HOL integers by big integer literals in target
  3330     languages.
  3331   - Code_Char represents HOL characters by character literals in target
  3332     languages.
  3333   - Code_Char_chr like Code_Char, but also offers treatment of character
  3334     codes; includes Code_Integer.
  3335   - Executable_Set allows to generate code for finite sets using lists.
  3336   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3337     denominator).
  3338   - Executable_Real implements a subset of real numbers, namly those
  3339     representable by rational numbers.
  3340   - Efficient_Nat implements natural numbers by integers, which in general will
  3341     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3342     includes Code_Integer.
  3343   - Code_Index provides an additional datatype index which is mapped to
  3344     target-language built-in integers.
  3345   - Code_Message provides an additional datatype message_string which is isomorphic to
  3346     strings; messages are mapped to target-language strings.
  3347 
  3348 * New package for inductive predicates
  3349 
  3350   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3351 
  3352     inductive
  3353       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3354       for z_1 :: U_1 and ... and z_n :: U_m
  3355     where
  3356       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3357     | ...
  3358 
  3359   with full support for type-inference, rather than
  3360 
  3361     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3362 
  3363     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3364     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3365 
  3366     inductive "s z_1 ... z_m"
  3367     intros
  3368       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3369       ...
  3370 
  3371   For backward compatibility, there is a wrapper allowing inductive
  3372   sets to be defined with the new package via
  3373 
  3374     inductive_set
  3375       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3376       for z_1 :: U_1 and ... and z_n :: U_m
  3377     where
  3378       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3379     | ...
  3380 
  3381   or
  3382 
  3383     inductive_set
  3384       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3385       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3386       for z_1 :: U_1 and ... and z_n :: U_m
  3387     where
  3388       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3389     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3390     | ...
  3391 
  3392   if the additional syntax "p ..." is required.
  3393 
  3394   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3395   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3396 
  3397   INCOMPATIBILITIES:
  3398 
  3399   - Since declaration and definition of inductive sets or predicates
  3400     is no longer separated, abbreviations involving the newly
  3401     introduced sets or predicates must be specified together with the
  3402     introduction rules after the 'where' keyword (see above), rather
  3403     than before the actual inductive definition.
  3404 
  3405   - The variables in induction and elimination rules are now
  3406     quantified in the order of their occurrence in the introduction
  3407     rules, rather than in alphabetical order. Since this may break
  3408     some proofs, these proofs either have to be repaired, e.g. by
  3409     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3410     statements of the form
  3411 
  3412       case (rule_i a_i_1 ... a_i_{k_i})
  3413 
  3414     or the old order of quantification has to be restored by explicitly adding
  3415     meta-level quantifiers in the introduction rules, i.e.
  3416 
  3417       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3418 
  3419   - The format of the elimination rules is now
  3420 
  3421       p z_1 ... z_m x_1 ... x_n ==>
  3422         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3423         ==> ... ==> P
  3424 
  3425     for predicates and
  3426 
  3427       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3428         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3429         ==> ... ==> P
  3430 
  3431     for sets rather than
  3432 
  3433       x : s z_1 ... z_m ==>
  3434         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3435         ==> ... ==> P
  3436 
  3437     This may require terms in goals to be expanded to n-tuples
  3438     (e.g. using case_tac or simplification with the split_paired_all
  3439     rule) before the above elimination rule is applicable.
  3440 
  3441   - The elimination or case analysis rules for (mutually) inductive
  3442     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3443     list of rules "p_1_..._p_k.elims" is no longer available.
  3444 
  3445 * New package "function"/"fun" for general recursive functions,
  3446 supporting mutual and nested recursion, definitions in local contexts,
  3447 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3448 for small examples, and the separate tutorial on the function
  3449 package. The old recdef "package" is still available as before, but
  3450 users are encouraged to use the new package.
  3451 
  3452 * Method "lexicographic_order" automatically synthesizes termination
  3453 relations as lexicographic combinations of size measures. 
  3454 
  3455 * Case-expressions allow arbitrary constructor-patterns (including
  3456 "_") and take their order into account, like in functional
  3457 programming.  Internally, this is translated into nested
  3458 case-expressions; missing cases are added and mapped to the predefined
  3459 constant "undefined". In complicated cases printing may no longer show
  3460 the original input but the internal form. Lambda-abstractions allow
  3461 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3462 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3463 variable.
  3464 
  3465 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3466 is an abbreviation for "of_nat :: nat => int". The simplification
  3467 rules for "of_nat" have been changed to work like "int" did
  3468 previously.  Potential INCOMPATIBILITY:
  3469   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3470   - of_nat_diff and of_nat_mult are no longer default simp rules
  3471 
  3472 * Method "algebra" solves polynomial equations over (semi)rings using
  3473 Groebner bases. The (semi)ring structure is defined by locales and the
  3474 tool setup depends on that generic context. Installing the method for
  3475 a specific type involves instantiating the locale and possibly adding
  3476 declarations for computation on the coefficients.  The method is
  3477 already instantiated for natural numbers and for the axiomatic class
  3478 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3479 CALCULEMUS 2007 for the general principles underlying this
  3480 architecture of context-aware proof-tools.
  3481 
  3482 * Method "ferrack" implements quantifier elimination over
  3483 special-purpose dense linear orders using locales (analogous to
  3484 "algebra"). The method is already installed for class
  3485 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3486 rat, etc.
  3487 
  3488 * Former constant "List.op @" now named "List.append".  Use ML
  3489 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3490 circumvent possible incompatibilities when working on ML level.
  3491 
  3492 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3493 
  3494 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3495 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3496 
  3497 * New syntax for Haskell-like list comprehension (input only), eg.
  3498 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3499 
  3500 * The special syntax for function "filter" has changed from [x :
  3501 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3502 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3503 
  3504 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3505 defined on nat only, as an abbreviation for [a..<Suc b]
  3506 INCOMPATIBILITY.
  3507 
  3508 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3509 
  3510 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3511 
  3512 * New lemma collection field_simps (an extension of ring_simps) for
  3513 manipulating (in)equations involving division. Multiplies with all
  3514 denominators that can be proved to be non-zero (in equations) or
  3515 positive/negative (in inequations).
  3516 
  3517 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3518 have been improved and renamed to ring_simps, group_simps and
  3519 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3520 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3521 
  3522 * Theory Library/Commutative_Ring: switched from recdef to function
  3523 package; constants add, mul, pow now curried.  Infix syntax for
  3524 algebraic operations.
  3525 
  3526 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3527 INCOMPATIBILITY.
  3528 
  3529 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3530 INCOMPATIBILITY.
  3531 
  3532 * HOL/records: generalised field-update to take a function on the
  3533 field rather than the new value: r(|A := x|) is translated to A_update
  3534 (K x) r The K-combinator that is internally used is called K_record.
  3535 INCOMPATIBILITY: Usage of the plain update functions has to be
  3536 adapted.
  3537  
  3538 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3539 * x = 0, which are required for a semiring.  Richer structures do not
  3540 inherit from semiring_0 anymore, because this property is a theorem
  3541 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3542 there is more to prove, but this is mostly trivial.
  3543 
  3544 * Class "recpower" is generalized to arbitrary monoids, not just
  3545 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3546 commutativity or semiring properties additionally.
  3547 
  3548 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3549 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3550 better use 'abbreviation'.
  3551 
  3552 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3553 
  3554 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3555 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3556 significant changes for setting up numeral syntax for types:
  3557   - New constants Numeral.pred and Numeral.succ instead
  3558       of former Numeral.bin_pred and Numeral.bin_succ.
  3559   - Use integer operations instead of bin_add, bin_mult and so on.
  3560   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3561   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3562 
  3563 See src/HOL/Integ/IntArith.thy for an example setup.
  3564 
  3565 * Command 'normal_form' computes the normal form of a term that may
  3566 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3567 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3568 heavy-duty computations because the functions are compiled to ML
  3569 first.  Correspondingly, a method "normalization" is provided.  See
  3570 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3571 
  3572 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3573 25 like -->); output depends on the "iff" print_mode, the default is
  3574 "A = B" (with priority 50).
  3575 
  3576 * Relations less (<) and less_eq (<=) are also available on type bool.
  3577 Modified syntax to disallow nesting without explicit parentheses,
  3578 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3579 INCOMPATIBILITY.
  3580 
  3581 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3582 
  3583 * Relation composition operator "op O" now has precedence 75 and binds
  3584 stronger than union and intersection. INCOMPATIBILITY.
  3585 
  3586 * The old set interval syntax "{m..n(}" (and relatives) has been
  3587 removed.  Use "{m..<n}" (and relatives) instead.
  3588 
  3589 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3590 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3591 ``declare [[simproc del: neq]]''.
  3592 
  3593 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3594 True/False.
  3595 
  3596 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3597 
  3598 * Theorem setsum_mult renamed to setsum_right_distrib.
  3599 
  3600 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3601 ``rule'' method.
  3602 
  3603 * Reimplemented methods "sat" and "satx", with several improvements:
  3604 goals no longer need to be stated as "<prems> ==> False", equivalences
  3605 (i.e. "=" on type bool) are handled, variable names of the form
  3606 "lit_<n>" are no longer reserved, significant speedup.
  3607 
  3608 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3609 zChaff is still supported as well.
  3610 
  3611 * 'inductive' and 'datatype': provide projections of mutual rules,
  3612 bundled as foo_bar.inducts;
  3613 
  3614 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3615 Library.
  3616 
  3617 * Library: moved theory Accessible_Part to main HOL.
  3618 
  3619 * Library: added theory Coinductive_List of potentially infinite lists
  3620 as greatest fixed-point.
  3621 
  3622 * Library: added theory AssocList which implements (finite) maps as
  3623 association lists.
  3624 
  3625 * Method "evaluation" solves goals (i.e. a boolean expression)
  3626 efficiently by compiling it to ML.  The goal is "proved" (via an
  3627 oracle) if it evaluates to True.
  3628 
  3629 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3630 also when invoked by the simplifier.  This results in the Simplifier
  3631 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3632 Configuration option fast_arith_split_limit=0 recovers the old
  3633 behavior.
  3634 
  3635 * Support for hex (0x20) and binary (0b1001) numerals.
  3636 
  3637 * New method: reify eqs (t), where eqs are equations for an
  3638 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3639 parameter, computes a term s::'b and a list xs::'a list and proves the
  3640 theorem I xs s = t. This is also known as reification or quoting. The
  3641 resulting theorem is applied to the subgoal to substitute t with I xs
  3642 s.  If t is omitted, the subgoal itself is reified.
  3643 
  3644 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3645 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3646 where f is supposed to be a computable function (in the sense of code
  3647 generattion). The method uses reify to compute s and xs as above then
  3648 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3649 r and finally gets the theorem t = r, which is again applied to the
  3650 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3651 
  3652 * Reflection: Automatic reification now handels binding, an example is
  3653 available in src/HOL/ex/ReflectionEx.thy
  3654 
  3655 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3656 command 'statespace' that is similar to 'record', but introduces an
  3657 abstract specification based on the locale infrastructure instead of
  3658 HOL types.  This leads to extra flexibility in composing state spaces,
  3659 in particular multiple inheritance and renaming of components.
  3660 
  3661 
  3662 *** HOL-Complex ***
  3663 
  3664 * Hyperreal: Functions root and sqrt are now defined on negative real
  3665 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3666 Nonnegativity side conditions have been removed from many lemmas, so
  3667 that more subgoals may now be solved by simplification; potential
  3668 INCOMPATIBILITY.
  3669 
  3670 * Real: new type classes formalize real normed vector spaces and
  3671 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3672 and norm :: 'a => real.
  3673 
  3674 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3675 reals into other types. The overloaded constant Reals :: 'a set is now
  3676 defined as range of_real; potential INCOMPATIBILITY.
  3677 
  3678 * Real: proper support for ML code generation, including 'quickcheck'.
  3679 Reals are implemented as arbitrary precision rationals.
  3680 
  3681 * Hyperreal: Several constants that previously worked only for the
  3682 reals have been generalized, so they now work over arbitrary vector
  3683 spaces. Type annotations may need to be added in some cases; potential
  3684 INCOMPATIBILITY.
  3685 
  3686   Infinitesimal  :: ('a::real_normed_vector) star set
  3687   HFinite        :: ('a::real_normed_vector) star set
  3688   HInfinite      :: ('a::real_normed_vector) star set
  3689   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3690   monad          :: ('a::real_normed_vector) star => 'a star set
  3691   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3692   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3693   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3694   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3695   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3696   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3697   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3698   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3699   sgn            :: 'a::real_normed_vector => 'a
  3700   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3701 
  3702 * Complex: Some complex-specific constants are now abbreviations for
  3703 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3704 hnorm.  Other constants have been entirely removed in favor of the
  3705 polymorphic versions (INCOMPATIBILITY):
  3706 
  3707   approx        <-- capprox
  3708   HFinite       <-- CFinite
  3709   HInfinite     <-- CInfinite
  3710   Infinitesimal <-- CInfinitesimal
  3711   monad         <-- cmonad
  3712   galaxy        <-- cgalaxy
  3713   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3714   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3715   (ns)deriv     <-- (ns)cderiv
  3716 
  3717 
  3718 *** HOL-Algebra ***
  3719 
  3720 * Formalisation of ideals and the quotient construction over rings.
  3721 
  3722 * Order and lattice theory no longer based on records.
  3723 INCOMPATIBILITY.
  3724 
  3725 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3726 greatest_closed.  INCOMPATIBILITY.
  3727 
  3728 * Method algebra is now set up via an attribute.  For examples see
  3729 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3730 of algebraic structures.
  3731 
  3732 * Renamed theory CRing to Ring.
  3733 
  3734 
  3735 *** HOL-Nominal ***
  3736 
  3737 * Substantial, yet incomplete support for nominal datatypes (binding
  3738 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3739 src/HOL/Nominal/Examples.  Prospective users should consult
  3740 http://isabelle.in.tum.de/nominal/
  3741 
  3742 
  3743 *** ML ***
  3744 
  3745 * ML basics: just one true type int, which coincides with IntInf.int
  3746 (even on SML/NJ).
  3747 
  3748 * ML within Isar: antiquotations allow to embed statically-checked
  3749 formal entities in the source, referring to the context available at
  3750 compile-time.  For example:
  3751 
  3752 ML {* @{sort "{zero,one}"} *}
  3753 ML {* @{typ "'a => 'b"} *}
  3754 ML {* @{term "%x. x"} *}
  3755 ML {* @{prop "x == y"} *}
  3756 ML {* @{ctyp "'a => 'b"} *}
  3757 ML {* @{cterm "%x. x"} *}
  3758 ML {* @{cprop "x == y"} *}
  3759 ML {* @{thm asm_rl} *}
  3760 ML {* @{thms asm_rl} *}
  3761 ML {* @{type_name c} *}
  3762 ML {* @{type_syntax c} *}
  3763 ML {* @{const_name c} *}
  3764 ML {* @{const_syntax c} *}
  3765 ML {* @{context} *}
  3766 ML {* @{theory} *}
  3767 ML {* @{theory Pure} *}
  3768 ML {* @{theory_ref} *}
  3769 ML {* @{theory_ref Pure} *}
  3770 ML {* @{simpset} *}
  3771 ML {* @{claset} *}
  3772 ML {* @{clasimpset} *}
  3773 
  3774 The same works for sources being ``used'' within an Isar context.
  3775 
  3776 * ML in Isar: improved error reporting; extra verbosity with
  3777 ML_Context.trace enabled.
  3778 
  3779 * Pure/General/table.ML: the join operations now works via exceptions
  3780 DUP/SAME instead of type option. This is simpler in simple cases, and
  3781 admits slightly more efficient complex applications.
  3782 
  3783 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3784 use Context.generic instead of just theory.
  3785 
  3786 * Pure: datatype Context.generic joins theory/Proof.context and
  3787 provides some facilities for code that works in either kind of
  3788 context, notably GenericDataFun for uniform theory and proof data.
  3789 
  3790 * Pure: simplified internal attribute type, which is now always
  3791 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3792 local (Proof.context) attributes have been discontinued, while
  3793 minimizing code duplication. Thm.rule_attribute and
  3794 Thm.declaration_attribute build canonical attributes; see also structure
  3795 Context for further operations on Context.generic, notably
  3796 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3797 declarations and definitions.
  3798 
  3799 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3800 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3801 init only required for impure data. INCOMPATIBILITY: empty really need
  3802 to be empty (no dependencies on theory content!)
  3803 
  3804 * Pure/kernel: consts certification ignores sort constraints given in
  3805 signature declarations. (This information is not relevant to the
  3806 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3807 potential INCOMPATIBILITY.
  3808 
  3809 * Pure: axiomatic type classes are now purely definitional, with
  3810 explicit proofs of class axioms and super class relations performed
  3811 internally. See Pure/axclass.ML for the main internal interfaces --
  3812 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3813 AxClass.axiomatize_class/classrel/arity supersede
  3814 Sign.add_classes/classrel/arities.
  3815 
  3816 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3817 global/local versions on theory vs. Proof.context have been
  3818 discontinued; Attrib.syntax and Method.syntax have been adapted
  3819 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3820 attributes, methods, etc.
  3821 
  3822 * Pure: several functions of signature "... -> theory -> theory * ..."
  3823 have been reoriented to "... -> theory -> ... * theory" in order to
  3824 allow natural usage in combination with the ||>, ||>>, |-> and
  3825 fold_map combinators.
  3826 
  3827 * Pure: official theorem names (closed derivations) and additional
  3828 comments (tags) are now strictly separate.  Name hints -- which are
  3829 maintained as tags -- may be attached any time without affecting the
  3830 derivation.
  3831 
  3832 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3833 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3834 achieve the old behaviour.
  3835 
  3836 * Pure: the "Goal" constant is now called "prop", supporting a
  3837 slightly more general idea of ``protecting'' meta-level rule
  3838 statements.
  3839 
  3840 * Pure: Logic.(un)varify only works in a global context, which is now
  3841 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3842 Logic.legacy_(un)varify as temporary workaround.
  3843 
  3844 * Pure: structure Name provides scalable operations for generating
  3845 internal variable names, notably Name.variants etc.  This replaces
  3846 some popular functions from term.ML:
  3847 
  3848   Term.variant		->  Name.variant
  3849   Term.variantlist	->  Name.variant_list
  3850   Term.invent_names	->  Name.invent_list
  3851 
  3852 Note that low-level renaming rarely occurs in new code -- operations
  3853 from structure Variable are used instead (see below).
  3854 
  3855 * Pure: structure Variable provides fundamental operations for proper
  3856 treatment of fixed/schematic variables in a context.  For example,
  3857 Variable.import introduces fixes for schematics of given facts and
  3858 Variable.export reverses the effect (up to renaming) -- this replaces
  3859 various freeze_thaw operations.
  3860 
  3861 * Pure: structure Goal provides simple interfaces for
  3862 init/conclude/finish and tactical prove operations (replacing former
  3863 Tactic.prove).  Goal.prove is the canonical way to prove results
  3864 within a given context; Goal.prove_global is a degraded version for
  3865 theory level goals, including a global Drule.standard.  Note that
  3866 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3867 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3868 in a locale context).
  3869 
  3870 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3871 and type checking (Syntax.check_term etc.), with common combinations
  3872 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3873 which are considered legacy and await removal.
  3874 
  3875 * Pure/Syntax: generic interfaces for type unchecking
  3876 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3877 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3878 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3879 available for convenience, but refer to the very same operations using
  3880 a mere theory instead of a full context.
  3881 
  3882 * Isar: simplified treatment of user-level errors, using exception
  3883 ERROR of string uniformly.  Function error now merely raises ERROR,
  3884 without any side effect on output channels.  The Isar toplevel takes
  3885 care of proper display of ERROR exceptions.  ML code may use plain
  3886 handle/can/try; cat_error may be used to concatenate errors like this:
  3887 
  3888   ... handle ERROR msg => cat_error msg "..."
  3889 
  3890 Toplevel ML code (run directly or through the Isar toplevel) may be
  3891 embedded into the Isar toplevel with exception display/debug like
  3892 this:
  3893 
  3894   Isar.toplevel (fn () => ...)
  3895 
  3896 INCOMPATIBILITY, removed special transform_error facilities, removed
  3897 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3898 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3899 -- use plain ERROR instead.
  3900 
  3901 * Isar: theory setup now has type (theory -> theory), instead of a
  3902 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3903 
  3904 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3905 ProofContext.debug/verbose flags.
  3906 
  3907 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3908 theory before entering a proof state.  Transactions now always see a
  3909 quasi-functional intermediate checkpoint, both in interactive and
  3910 batch mode.
  3911 
  3912 * Isar: simplified interfaces for outer syntax.  Renamed
  3913 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3914 OuterSyntax.add_parsers -- this functionality is now included in
  3915 OuterSyntax.command etc.  INCOMPATIBILITY.
  3916 
  3917 * Simplifier: the simpset of a running simplification process now
  3918 contains a proof context (cf. Simplifier.the_context), which is the
  3919 very context that the initial simpset has been retrieved from (by
  3920 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3921 (solver, looper etc.) may depend on arbitrary proof data.
  3922 
  3923 * Simplifier.inherit_context inherits the proof context (plus the
  3924 local bounds) of the current simplification process; any simproc
  3925 etc. that calls the Simplifier recursively should do this!  Removed
  3926 former Simplifier.inherit_bounds, which is already included here --
  3927 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3928 specify an explicit context using Simplifier.context/theory_context.
  3929 
  3930 * Simplifier/Classical Reasoner: more abstract interfaces
  3931 change_simpset/claset for modifying the simpset/claset reference of a
  3932 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3933 INCOMPATIBILITY.
  3934 
  3935 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3936 "Trueprop" etc.
  3937 
  3938 
  3939 *** System ***
  3940 
  3941 * settings: the default heap location within ISABELLE_HOME_USER now
  3942 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3943 Isabelle installations.
  3944 
  3945 * isabelle-process: option -S (secure mode) disables some critical
  3946 operations, notably runtime compilation and evaluation of ML source
  3947 code.
  3948 
  3949 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3950 
  3951 * Support for parallel execution, using native multicore support of
  3952 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3953 independent theories, according to the given theory header
  3954 specifications. The maximum number of worker threads is specified via
  3955 usedir option -M or the "max-threads" setting in Proof General. A
  3956 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3957 to 6 on a 8-core machine.  User-code needs to observe certain
  3958 guidelines for thread-safe programming, see appendix A in the Isar
  3959 Implementation manual.
  3960 
  3961 
  3962 
  3963 New in Isabelle2005 (October 2005)
  3964 ----------------------------------
  3965 
  3966 *** General ***
  3967 
  3968 * Theory headers: the new header syntax for Isar theories is
  3969 
  3970   theory <name>
  3971   imports <theory1> ... <theoryN>
  3972   uses <file1> ... <fileM>
  3973   begin
  3974 
  3975 where the 'uses' part is optional.  The previous syntax
  3976 
  3977   theory <name> = <theory1> + ... + <theoryN>:
  3978 
  3979 will disappear in the next release.  Use isatool fixheaders to convert
  3980 existing theory files.  Note that there is no change in ancient
  3981 non-Isar theories now, but these will disappear soon.
  3982 
  3983 * Theory loader: parent theories can now also be referred to via
  3984 relative and absolute paths.
  3985 
  3986 * Command 'find_theorems' searches for a list of criteria instead of a
  3987 list of constants. Known criteria are: intro, elim, dest, name:string,
  3988 simp:term, and any term. Criteria can be preceded by '-' to select
  3989 theorems that do not match. Intro, elim, dest select theorems that
  3990 match the current goal, name:s selects theorems whose fully qualified
  3991 name contain s, and simp:term selects all simplification rules whose
  3992 lhs match term.  Any other term is interpreted as pattern and selects
  3993 all theorems matching the pattern. Available in ProofGeneral under
  3994 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3995 
  3996   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3997 
  3998 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3999 matching the current goal as introduction rule and not having "HOL."
  4000 in their name (i.e. not being defined in theory HOL).
  4001 
  4002 * Command 'thms_containing' has been discontinued in favour of
  4003 'find_theorems'; INCOMPATIBILITY.
  4004 
  4005 * Communication with Proof General is now 8bit clean, which means that
  4006 Unicode text in UTF-8 encoding may be used within theory texts (both
  4007 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4008 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4009 
  4010   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4011   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4012 
  4013 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4014 Classical Reasoner.  Typical big applications run around 2 times
  4015 faster.
  4016 
  4017 
  4018 *** Document preparation ***
  4019 
  4020 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4021 of raw sources.  Only those symbols that do not require additional
  4022 LaTeX packages (depending on comments in isabellesym.sty) are
  4023 displayed properly, everything else is left verbatim.  isatool display
  4024 and isatool print are used as front ends (these are subject to the
  4025 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4026 
  4027 * Command tags control specific markup of certain regions of text,
  4028 notably folding and hiding.  Predefined tags include "theory" (for
  4029 theory begin and end), "proof" for proof commands, and "ML" for
  4030 commands involving ML code; the additional tags "visible" and
  4031 "invisible" are unused by default.  Users may give explicit tag
  4032 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4033 interpretation of tags is determined by the LaTeX job during document
  4034 preparation: see option -V of isatool usedir, or options -n and -t of
  4035 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4036 \isadroptag.
  4037 
  4038 Several document versions may be produced at the same time via isatool
  4039 usedir (the generated index.html will link all of them).  Typical
  4040 specifications include ''-V document=theory,proof,ML'' to present
  4041 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4042 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4043 these parts without any formal replacement text.  The Isabelle site
  4044 default settings produce ''document'' and ''outline'' versions as
  4045 specified above.
  4046 
  4047 * Several new antiquotations:
  4048 
  4049   @{term_type term} prints a term with its type annotated;
  4050 
  4051   @{typeof term} prints the type of a term;
  4052 
  4053   @{const const} is the same as @{term const}, but checks that the
  4054   argument is a known logical constant;
  4055 
  4056   @{term_style style term} and @{thm_style style thm} print a term or
  4057   theorem applying a "style" to it
  4058 
  4059   @{ML text}
  4060 
  4061 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4062 definitions, equations, inequations etc., 'concl' printing only the
  4063 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4064 to print the specified premise.  TermStyle.add_style provides an ML
  4065 interface for introducing further styles.  See also the "LaTeX Sugar"
  4066 document practical applications.  The ML antiquotation prints
  4067 type-checked ML expressions verbatim.
  4068 
  4069 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4070 and 'text' support optional locale specification '(in loc)', which
  4071 specifies the default context for interpreting antiquotations.  For
  4072 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4073 
  4074 * Option 'locale=NAME' of antiquotations specifies an alternative
  4075 context interpreting the subsequent argument.  For example: @{thm
  4076 [locale=lattice] inf_assoc}.
  4077 
  4078 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4079 a proof context.
  4080 
  4081 * Proper output of antiquotations for theory commands involving a
  4082 proof context (such as 'locale' or 'theorem (in loc) ...').
  4083 
  4084 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4085 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4086 
  4087 * isatool usedir: new option -C (default true) controls whether option
  4088 -D should include a copy of the original document directory; -C false
  4089 prevents unwanted effects such as copying of administrative CVS data.
  4090 
  4091 
  4092 *** Pure ***
  4093 
  4094 * Considerably improved version of 'constdefs' command.  Now performs
  4095 automatic type-inference of declared constants; additional support for
  4096 local structure declarations (cf. locales and HOL records), see also
  4097 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4098 sequential dependencies of definitions within a single 'constdefs'
  4099 section; moreover, the declared name needs to be an identifier.  If
  4100 all fails, consider to fall back on 'consts' and 'defs' separately.
  4101 
  4102 * Improved indexed syntax and implicit structures.  First of all,
  4103 indexed syntax provides a notational device for subscripted
  4104 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4105 expressions.  Secondly, in a local context with structure
  4106 declarations, number indexes \<^sub>n or the empty index (default
  4107 number 1) refer to a certain fixed variable implicitly; option
  4108 show_structs controls printing of implicit structures.  Typical
  4109 applications of these concepts involve record types and locales.
  4110 
  4111 * New command 'no_syntax' removes grammar declarations (and
  4112 translations) resulting from the given syntax specification, which is
  4113 interpreted in the same manner as for the 'syntax' command.
  4114 
  4115 * 'Advanced' translation functions (parse_translation etc.) may depend
  4116 on the signature of the theory context being presently used for
  4117 parsing/printing, see also isar-ref manual.
  4118 
  4119 * Improved 'oracle' command provides a type-safe interface to turn an
  4120 ML expression of type theory -> T -> term into a primitive rule of
  4121 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4122 is already included here); see also FOL/ex/IffExample.thy;
  4123 INCOMPATIBILITY.
  4124 
  4125 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4126 before); "cI" is no longer bound, use "c.intro" instead.
  4127 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4128 axclasses vs. locales.
  4129 
  4130 * Improved internal renaming of symbolic identifiers -- attach primes
  4131 instead of base 26 numbers.
  4132 
  4133 * New flag show_question_marks controls printing of leading question
  4134 marks in schematic variable names.
  4135 
  4136 * In schematic variable names, *any* symbol following \<^isub> or
  4137 \<^isup> is now treated as part of the base name.  For example, the
  4138 following works without printing of awkward ".0" indexes:
  4139 
  4140   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4141     by simp
  4142 
  4143 * Inner syntax includes (*(*nested*) comments*).
  4144 
  4145 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4146 annotations as "(00...)".
  4147 
  4148 * Clear separation of logical types and nonterminals, where the latter
  4149 may only occur in 'syntax' specifications or type abbreviations.
  4150 Before that distinction was only partially implemented via type class
  4151 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4152 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4153 exotic syntax specifications may require further adaption
  4154 (e.g. Cube/Cube.thy).
  4155 
  4156 * Removed obsolete type class "logic", use the top sort {} instead.
  4157 Note that non-logical types should be declared as 'nonterminals'
  4158 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4159 specifications.
  4160 
  4161 * Attributes 'induct' and 'cases': type or set names may now be
  4162 locally fixed variables as well.
  4163 
  4164 * Simplifier: can now control the depth to which conditional rewriting
  4165 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4166 Limit.
  4167 
  4168 * Simplifier: simplification procedures may now take the current
  4169 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4170 interface), which is very useful for calling the Simplifier
  4171 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4172 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4173 low-level mk_simproc no longer applies Logic.varify internally, to
  4174 allow for use in a context of fixed variables.
  4175 
  4176 * thin_tac now works even if the assumption being deleted contains !!
  4177 or ==>.  More generally, erule now works even if the major premise of
  4178 the elimination rule contains !! or ==>.
  4179 
  4180 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4181 
  4182 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4183 from Pure, which contains all common declarations already.  Both
  4184 theories are defined via plain Isabelle/Isar .thy files.
  4185 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4186 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4187 use isatool fixcpure to adapt your theory and ML sources.
  4188 
  4189 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4190 selections of theorems in named facts via index ranges.
  4191 
  4192 * 'print_theorems': in theory mode, really print the difference
  4193 wrt. the last state (works for interactive theory development only),
  4194 in proof mode print all local facts (cf. 'print_facts');
  4195 
  4196 * 'hide': option '(open)' hides only base names.
  4197 
  4198 * More efficient treatment of intermediate checkpoints in interactive
  4199 theory development.
  4200 
  4201 * Code generator is now invoked via code_module (incremental code
  4202 generation) and code_library (modular code generation, ML structures
  4203 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4204 must be quoted when used as identifiers.
  4205 
  4206 * New 'value' command for reading, evaluating and printing terms using
  4207 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4208 quoted when used as identifier.
  4209 
  4210 
  4211 *** Locales ***
  4212 
  4213 * New commands for the interpretation of locale expressions in
  4214 theories (1), locales (2) and proof contexts (3).  These generate
  4215 proof obligations from the expression specification.  After the
  4216 obligations have been discharged, theorems of the expression are added
  4217 to the theory, target locale or proof context.  The synopsis of the
  4218 commands is a follows:
  4219 
  4220   (1) interpretation expr inst
  4221   (2) interpretation target < expr
  4222   (3) interpret expr inst
  4223 
  4224 Interpretation in theories and proof contexts require a parameter
  4225 instantiation of terms from the current context.  This is applied to
  4226 specifications and theorems of the interpreted expression.
  4227 Interpretation in locales only permits parameter renaming through the
  4228 locale expression.  Interpretation is smart in that interpretations
  4229 that are active already do not occur in proof obligations, neither are
  4230 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4231 inspect active interpretations of a particular locale.  For details,
  4232 see the Isar Reference manual.  Examples can be found in
  4233 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4234 
  4235 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4236 'interpret' instead.
  4237 
  4238 * New context element 'constrains' for adding type constraints to
  4239 parameters.
  4240 
  4241 * Context expressions: renaming of parameters with syntax
  4242 redeclaration.
  4243 
  4244 * Locale declaration: 'includes' disallowed.
  4245 
  4246 * Proper static binding of attribute syntax -- i.e. types / terms /
  4247 facts mentioned as arguments are always those of the locale definition
  4248 context, independently of the context of later invocations.  Moreover,
  4249 locale operations (renaming and type / term instantiation) are applied
  4250 to attribute arguments as expected.
  4251 
  4252 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4253 actual attributes; rare situations may require Attrib.attribute to
  4254 embed those attributes into Attrib.src that lack concrete syntax.
  4255 Attribute implementations need to cooperate properly with the static
  4256 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4257 Attrib.XXX_thm etc. already do the right thing without further
  4258 intervention.  Only unusual applications -- such as "where" or "of"
  4259 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4260 on the context and the facts involved -- may have to assign parsed
  4261 values to argument tokens explicitly.
  4262 
  4263 * Changed parameter management in theorem generation for long goal
  4264 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4265 theorem statement in rare situations.
  4266 
  4267 * Locale inspection command 'print_locale' omits notes elements.  Use
  4268 'print_locale!' to have them included in the output.
  4269 
  4270 
  4271 *** Provers ***
  4272 
  4273 * Provers/hypsubst.ML: improved version of the subst method, for
  4274 single-step rewriting: it now works in bound variable contexts. New is
  4275 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4276 rewrite a different subterm than the original subst method, which is
  4277 still available as 'simplesubst'.
  4278 
  4279 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4280 and quasi orders.
  4281 
  4282 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4283 reflexive-transitive closure of relations.
  4284 
  4285 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4286 limit (previously hard-coded with a value of 20) user-definable.
  4287 
  4288 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4289 is peformed already.  Object-logics merely need to finish their
  4290 initial simpset configuration as before.  INCOMPATIBILITY.
  4291 
  4292 
  4293 *** HOL ***
  4294 
  4295 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4296 
  4297   syntax (epsilon)
  4298     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4299 
  4300 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4301 and x-symbol; use option '-m epsilon' to get it actually printed.
  4302 Moreover, the mathematically important symbolic identifier \<epsilon>
  4303 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4304 
  4305 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4306 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4307 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4308 support corresponding Isar calculations.
  4309 
  4310 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4311 instead of ":".
  4312 
  4313 * theory SetInterval: changed the syntax for open intervals:
  4314 
  4315   Old       New
  4316   {..n(}    {..<n}
  4317   {)n..}    {n<..}
  4318   {m..n(}   {m..<n}
  4319   {)m..n}   {m<..n}
  4320   {)m..n(}  {m<..<n}
  4321 
  4322 The old syntax is still supported but will disappear in the next
  4323 release.  For conversion use the following Emacs search and replace
  4324 patterns (these are not perfect but work quite well):
  4325 
  4326   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4327   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4328 
  4329 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4330 equalities in commutative rings; method 'algebra' provides a generic
  4331 interface.
  4332 
  4333 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4334 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4335 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4336 be a tuple pattern.
  4337 
  4338 Some new syntax forms are available:
  4339 
  4340   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4341   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4342   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4343   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4344 
  4345 The latter form "\<Sum>x < k. e" used to be based on a separate
  4346 function "Summation", which has been discontinued.
  4347 
  4348 * theory Finite_Set: in structured induction proofs, the insert case
  4349 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4350 (insert F x)'.
  4351 
  4352 * The 'refute' command has been extended to support a much larger
  4353 fragment of HOL, including axiomatic type classes, constdefs and
  4354 typedefs, inductive datatypes and recursion.
  4355 
  4356 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4357 Requires zChaff with proof generation to be installed.  See
  4358 HOL/ex/SAT_Examples.thy for examples.
  4359 
  4360 * Datatype induction via method 'induct' now preserves the name of the
  4361 induction variable. For example, when proving P(xs::'a list) by
  4362 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4363 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4364 in unstructured proof scripts.
  4365 
  4366 * Reworked implementation of records.  Improved scalability for
  4367 records with many fields, avoiding performance problems for type
  4368 inference. Records are no longer composed of nested field types, but
  4369 of nested extension types. Therefore the record type only grows linear
  4370 in the number of extensions and not in the number of fields.  The
  4371 top-level (users) view on records is preserved.  Potential
  4372 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4373 old record representation. The type generated for a record is called
  4374 <record_name>_ext_type.
  4375 
  4376 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4377 proofs triggered by a record definition or a simproc (if
  4378 quick_and_dirty is enabled).  Definitions of large records can take
  4379 quite long.
  4380 
  4381 New simproc record_upd_simproc for simplification of multiple record
  4382 updates enabled by default.  Moreover, trivial updates are also
  4383 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4384 occasionally, since simplification is more powerful by default.
  4385 
  4386 * typedef: proper support for polymorphic sets, which contain extra
  4387 type-variables in the term.
  4388 
  4389 * Simplifier: automatically reasons about transitivity chains
  4390 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4391 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4392 old proofs break occasionally as simplification may now solve more
  4393 goals than previously.
  4394 
  4395 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4396 present.  Works for all partial orders (class "order"), in particular
  4397 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4398 just like y <= x.
  4399 
  4400 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4401 bound variable or a constant then the let is unfolded.  Otherwise
  4402 first a is simplified to b, and then f b is simplified to g. If
  4403 possible we abstract b from g arriving at "let x = b in h x",
  4404 otherwise we unfold the let and arrive at g.  The simproc can be
  4405 enabled/disabled by the reference use_let_simproc.  Potential
  4406 INCOMPATIBILITY since simplification is more powerful by default.
  4407 
  4408 * Classical reasoning: the meson method now accepts theorems as arguments.
  4409 
  4410 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4411 jobs to provide advice on the provability of subgoals.
  4412 
  4413 * Theory OrderedGroup and Ring_and_Field: various additions and
  4414 improvements to faciliate calculations involving equalities and
  4415 inequalities.
  4416 
  4417 The following theorems have been eliminated or modified
  4418 (INCOMPATIBILITY):
  4419 
  4420   abs_eq             now named abs_of_nonneg
  4421   abs_of_ge_0        now named abs_of_nonneg
  4422   abs_minus_eq       now named abs_of_nonpos
  4423   imp_abs_id         now named abs_of_nonneg
  4424   imp_abs_neg_id     now named abs_of_nonpos
  4425   mult_pos           now named mult_pos_pos
  4426   mult_pos_le        now named mult_nonneg_nonneg
  4427   mult_pos_neg_le    now named mult_nonneg_nonpos
  4428   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4429   mult_neg           now named mult_neg_neg
  4430   mult_neg_le        now named mult_nonpos_nonpos
  4431 
  4432 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4433      
  4434      zero_le_square
  4435      not_square_less_zero 
  4436 
  4437   The following lemmas have been deleted from Real/RealPow:
  4438   
  4439      realpow_zero_zero
  4440      realpow_two
  4441      realpow_less
  4442      zero_le_power
  4443      realpow_two_le
  4444      abs_realpow_two
  4445      realpow_two_abs     
  4446 
  4447 * Theory Parity: added rules for simplifying exponents.
  4448 
  4449 * Theory List:
  4450 
  4451 The following theorems have been eliminated or modified
  4452 (INCOMPATIBILITY):
  4453 
  4454   list_all_Nil       now named list_all.simps(1)
  4455   list_all_Cons      now named list_all.simps(2)
  4456   list_all_conv      now named list_all_iff
  4457   set_mem_eq         now named mem_iff
  4458 
  4459 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4460 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4461 
  4462 
  4463 *** HOL-Complex ***
  4464 
  4465 * Theory RealDef: better support for embedding natural numbers and
  4466 integers in the reals.
  4467 
  4468 The following theorems have been eliminated or modified
  4469 (INCOMPATIBILITY):
  4470 
  4471   exp_ge_add_one_self  now requires no hypotheses
  4472   real_of_int_add      reversed direction of equality (use [symmetric])
  4473   real_of_int_minus    reversed direction of equality (use [symmetric])
  4474   real_of_int_diff     reversed direction of equality (use [symmetric])
  4475   real_of_int_mult     reversed direction of equality (use [symmetric])
  4476 
  4477 * Theory RComplete: expanded support for floor and ceiling functions.
  4478 
  4479 * Theory Ln is new, with properties of the natural logarithm
  4480 
  4481 * Hyperreal: There is a new type constructor "star" for making
  4482 nonstandard types.  The old type names are now type synonyms:
  4483 
  4484   hypreal = real star
  4485   hypnat = nat star
  4486   hcomplex = complex star
  4487 
  4488 * Hyperreal: Many groups of similarly-defined constants have been
  4489 replaced by polymorphic versions (INCOMPATIBILITY):
  4490 
  4491   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4492 
  4493   starset      <-- starsetNat, starsetC
  4494   *s*          <-- *sNat*, *sc*
  4495   starset_n    <-- starsetNat_n, starsetC_n
  4496   *sn*         <-- *sNatn*, *scn*
  4497   InternalSets <-- InternalNatSets, InternalCSets
  4498 
  4499   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4500   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4501   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4502   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4503   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4504 
  4505 * Hyperreal: Many type-specific theorems have been removed in favor of
  4506 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4507 
  4508   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4509   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4510   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4511   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4512   right_minus <-- hypreal_add_minus
  4513   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4514   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4515   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4516   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4517   mult_1_right <-- hcomplex_mult_one_right
  4518   mult_zero_left <-- hcomplex_mult_zero_left
  4519   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4520   right_distrib <-- hypnat_add_mult_distrib2
  4521   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4522   right_inverse <-- hypreal_mult_inverse
  4523   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4524   order_refl <-- {hypreal,hypnat}_le_refl
  4525   order_trans <-- {hypreal,hypnat}_le_trans
  4526   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4527   order_less_le <-- {hypreal,hypnat}_less_le
  4528   linorder_linear <-- {hypreal,hypnat}_le_linear
  4529   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4530   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4531   add_nonneg_nonneg <-- hypreal_le_add_order
  4532 
  4533 * Hyperreal: Separate theorems having to do with type-specific
  4534 versions of constants have been merged into theorems that apply to the
  4535 new polymorphic constants (INCOMPATIBILITY):
  4536 
  4537   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4538   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4539   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4540   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4541   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4542   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4543   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4544   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4545   STAR_diff <-- {STAR,STARC}_diff
  4546   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4547     STARC_hcomplex_of_complex}_image_subset
  4548   starset_n_Un <-- starset{Nat,C}_n_Un
  4549   starset_n_Int <-- starset{Nat,C}_n_Int
  4550   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4551   starset_n_diff <-- starset{Nat,C}_n_diff
  4552   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4553   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4554   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4555   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4556   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4557   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4558   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4559   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4560   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4561   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4562   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4563   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4564   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4565   starfun_diff <-- starfun{C,RC,CR}_diff
  4566   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4567   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4568   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4569   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4570   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4571   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4572   starfun_Id <-- starfunC_Id
  4573   starfun_approx <-- starfun{Nat,CR}_approx
  4574   starfun_capprox <-- starfun{C,RC}_capprox
  4575   starfun_abs <-- starfunNat_rabs
  4576   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4577   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4578   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4579   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4580   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4581   starfun_add_approx <-- starfunCR_add_approx
  4582   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4583   starfun_divide <-- starfun{C,CR,RC}_divide
  4584   starfun_n <-- starfun{Nat,C}_n
  4585   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4586   starfun_n_add <-- starfun{Nat,C}_n_add
  4587   starfun_n_add_minus <-- starfunNat_n_add_minus
  4588   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4589   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4590   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4591 
  4592   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4593   star_n_minus <-- {hypreal,hcomplex}_minus
  4594   star_n_diff <-- {hypreal,hcomplex}_diff
  4595   star_n_mult <-- {hypreal,hcomplex}_mult
  4596   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4597   star_n_le <-- {hypreal,hypnat}_le
  4598   star_n_less <-- {hypreal,hypnat}_less
  4599   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4600   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4601   star_n_abs <-- hypreal_hrabs
  4602   star_n_divide <-- hcomplex_divide
  4603 
  4604   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4605   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4606   star_of_diff <-- hypreal_of_real_diff
  4607   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4608   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4609   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4610   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4611   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4612   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4613   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4614   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4615   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4616   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4617   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4618   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4619   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4620   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4621   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4622   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4623   star_of_power <-- hypreal_of_real_power
  4624   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4625 
  4626 * Hyperreal: new method "transfer" that implements the transfer
  4627 principle of nonstandard analysis. With a subgoal that mentions
  4628 nonstandard types like "'a star", the command "apply transfer"
  4629 replaces it with an equivalent one that mentions only standard types.
  4630 To be successful, all free variables must have standard types; non-
  4631 standard variables must have explicit universal quantifiers.
  4632 
  4633 * Hyperreal: A theory of Taylor series.
  4634 
  4635 
  4636 *** HOLCF ***
  4637 
  4638 * Discontinued special version of 'constdefs' (which used to support
  4639 continuous functions) in favor of the general Pure one with full
  4640 type-inference.
  4641 
  4642 * New simplification procedure for solving continuity conditions; it
  4643 is much faster on terms with many nested lambda abstractions (cubic
  4644 instead of exponential time).
  4645 
  4646 * New syntax for domain package: selector names are now optional.
  4647 Parentheses should be omitted unless argument is lazy, for example:
  4648 
  4649   domain 'a stream = cons "'a" (lazy "'a stream")
  4650 
  4651 * New command 'fixrec' for defining recursive functions with pattern
  4652 matching; defining multiple functions with mutual recursion is also
  4653 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4654 sinr, or any data constructor defined by the domain package. The given
  4655 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4656 syntax and examples.
  4657 
  4658 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4659 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4660 but the proof obligation additionally includes an admissibility
  4661 requirement. The packages generate instances of class cpo or pcpo,
  4662 with continuity and strictness theorems for Rep and Abs.
  4663 
  4664 * HOLCF: Many theorems have been renamed according to a more standard naming
  4665 scheme (INCOMPATIBILITY):
  4666 
  4667   foo_inject:  "foo$x = foo$y ==> x = y"
  4668   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4669   foo_less:    "(foo$x << foo$y) = (x << y)"
  4670   foo_strict:  "foo$UU = UU"
  4671   foo_defined: "... ==> foo$x ~= UU"
  4672   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4673 
  4674 
  4675 *** ZF ***
  4676 
  4677 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4678 including the First Isomorphism Theorem (on quotienting by the kernel
  4679 of a homomorphism).
  4680 
  4681 * ZF/Simplifier: install second copy of type solver that actually
  4682 makes use of TC rules declared to Isar proof contexts (or locales);
  4683 the old version is still required for ML proof scripts.
  4684 
  4685 
  4686 *** Cube ***
  4687 
  4688 * Converted to Isar theory format; use locales instead of axiomatic
  4689 theories.
  4690 
  4691 
  4692 *** ML ***
  4693 
  4694 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4695 for ||>, ||>>, |>>,
  4696 
  4697 * Pure/library.ML no longer defines its own option datatype, but uses
  4698 that of the SML basis, which has constructors NONE and SOME instead of
  4699 None and Some, as well as exception Option.Option instead of OPTION.
  4700 The functions the, if_none, is_some, is_none have been adapted
  4701 accordingly, while Option.map replaces apsome.
  4702 
  4703 * Pure/library.ML: the exception LIST has been given up in favour of
  4704 the standard exceptions Empty and Subscript, as well as
  4705 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4706 superceded by the standard hd and tl functions etc.
  4707 
  4708 A number of basic list functions are no longer exported to the ML
  4709 toplevel, as they are variants of predefined functions.  The following
  4710 suggests how one can translate existing code:
  4711 
  4712     rev_append xs ys = List.revAppend (xs, ys)
  4713     nth_elem (i, xs) = List.nth (xs, i)
  4714     last_elem xs = List.last xs
  4715     flat xss = List.concat xss
  4716     seq fs = List.app fs
  4717     partition P xs = List.partition P xs
  4718     mapfilter f xs = List.mapPartial f xs
  4719 
  4720 * Pure/library.ML: several combinators for linear functional
  4721 transformations, notably reverse application and composition:
  4722 
  4723   x |> f                f #> g
  4724   (x, y) |-> f          f #-> g
  4725 
  4726 * Pure/library.ML: introduced/changed precedence of infix operators:
  4727 
  4728   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4729   infix 2 ?;
  4730   infix 3 o oo ooo oooo;
  4731   infix 4 ~~ upto downto;
  4732 
  4733 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4734 infix operators.
  4735 
  4736 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4737 fold_map support linear functional transformations and nesting.  For
  4738 example:
  4739 
  4740   fold f [x1, ..., xN] y =
  4741     y |> f x1 |> ... |> f xN
  4742 
  4743   (fold o fold) f [xs1, ..., xsN] y =
  4744     y |> fold f xs1 |> ... |> fold f xsN
  4745 
  4746   fold f [x1, ..., xN] =
  4747     f x1 #> ... #> f xN
  4748 
  4749   (fold o fold) f [xs1, ..., xsN] =
  4750     fold f xs1 #> ... #> fold f xsN
  4751 
  4752 * Pure/library.ML: the following selectors on type 'a option are
  4753 available:
  4754 
  4755   the:               'a option -> 'a  (*partial*)
  4756   these:             'a option -> 'a  where 'a = 'b list
  4757   the_default: 'a -> 'a option -> 'a
  4758   the_list:          'a option -> 'a list
  4759 
  4760 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4761 basic operations for association lists, following natural argument
  4762 order; moreover the explicit equality predicate passed here avoids
  4763 potentially expensive polymorphic runtime equality checks.
  4764 The old functions may be expressed as follows:
  4765 
  4766   assoc = uncurry (AList.lookup (op =))
  4767   assocs = these oo AList.lookup (op =)
  4768   overwrite = uncurry (AList.update (op =)) o swap
  4769 
  4770 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4771 
  4772   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4773   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4774 
  4775 replacing make_keylist and keyfilter (occassionally used)
  4776 Naive rewrites:
  4777 
  4778   make_keylist = AList.make
  4779   keyfilter = AList.find (op =)
  4780 
  4781 * eq_fst and eq_snd now take explicit equality parameter, thus
  4782   avoiding eqtypes. Naive rewrites:
  4783 
  4784     eq_fst = eq_fst (op =)
  4785     eq_snd = eq_snd (op =)
  4786 
  4787 * Removed deprecated apl and apr (rarely used).
  4788   Naive rewrites:
  4789 
  4790     apl (n, op) =>>= curry op n
  4791     apr (op, m) =>>= fn n => op (n, m)
  4792 
  4793 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4794 provides a reasonably efficient light-weight implementation of sets as
  4795 lists.
  4796 
  4797 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4798 few new operations; existing lookup and update are now curried to
  4799 follow natural argument order (for use with fold etc.);
  4800 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4801 
  4802 * Pure/General: output via the Isabelle channels of
  4803 writeln/warning/error etc. is now passed through Output.output, with a
  4804 hook for arbitrary transformations depending on the print_mode
  4805 (cf. Output.add_mode -- the first active mode that provides a output
  4806 function wins).  Already formatted output may be embedded into further
  4807 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4808 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4809 accommodate easy composition of diagnostic messages etc.  Programmers
  4810 rarely need to care about Output.output or Output.raw at all, with
  4811 some notable exceptions: Output.output is required when bypassing the
  4812 standard channels (writeln etc.), or in token translations to produce
  4813 properly formatted results; Output.raw is required when capturing
  4814 already output material that will eventually be presented to the user
  4815 a second time.  For the default print mode, both Output.output and
  4816 Output.raw have no effect.
  4817 
  4818 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4819 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4820 cumulative results are displayed at the end of a batch session.
  4821 
  4822 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4823 replaced by File.platform_path and File.shell_path (with appropriate
  4824 hooks).  This provides a clean interface for unusual systems where the
  4825 internal and external process view of file names are different.
  4826 
  4827 * Pure: more efficient orders for basic syntactic entities: added
  4828 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4829 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4830 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4831 orders now -- potential INCOMPATIBILITY for code that depends on a
  4832 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4833 Library.sort_strings on result).
  4834 
  4835 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4836 fold_types traverse types/terms from left to right, observing natural
  4837 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4838 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4839 
  4840 * Pure: name spaces have been refined, with significant changes of the
  4841 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4842 to extern(_table).  The plain name entry path is superceded by a
  4843 general 'naming' context, which also includes the 'policy' to produce
  4844 a fully qualified name and external accesses of a fully qualified
  4845 name; NameSpace.extend is superceded by context dependent
  4846 Sign.declare_name.  Several theory and proof context operations modify
  4847 the naming context.  Especially note Theory.restore_naming and
  4848 ProofContext.restore_naming to get back to a sane state; note that
  4849 Theory.add_path is no longer sufficient to recover from
  4850 Theory.absolute_path in particular.
  4851 
  4852 * Pure: new flags short_names (default false) and unique_names
  4853 (default true) for controlling output of qualified names.  If
  4854 short_names is set, names are printed unqualified.  If unique_names is
  4855 reset, the name prefix is reduced to the minimum required to achieve
  4856 the original result when interning again, even if there is an overlap
  4857 with earlier declarations.
  4858 
  4859 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4860 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4861 (useful for printing error messages).  INCOMPATIBILITY.
  4862 
  4863 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4864 Theory.theory are now identified, referring to the universal
  4865 Context.theory (see Pure/context.ML).  Actual signature and theory
  4866 content is managed as theory data.  The old code and interfaces were
  4867 spread over many files and structures; the new arrangement introduces
  4868 considerable INCOMPATIBILITY to gain more clarity:
  4869 
  4870   Context -- theory management operations (name, identity, inclusion,
  4871     parents, ancestors, merge, etc.), plus generic theory data;
  4872 
  4873   Sign -- logical signature and syntax operations (declaring consts,
  4874     types, etc.), plus certify/read for common entities;
  4875 
  4876   Theory -- logical theory operations (stating axioms, definitions,
  4877     oracles), plus a copy of logical signature operations (consts,
  4878     types, etc.); also a few basic management operations (Theory.copy,
  4879     Theory.merge, etc.)
  4880 
  4881 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4882 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4883 for convenience -- they merely return the theory.
  4884 
  4885 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4886 
  4887 * Pure: the Isar proof context type is already defined early in Pure
  4888 as Context.proof (note that ProofContext.context and Proof.context are
  4889 aliases, where the latter is the preferred name).  This enables other
  4890 Isabelle components to refer to that type even before Isar is present.
  4891 
  4892 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4893 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4894 any of these kinds.  For example, Sign.intern typeK is now
  4895 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4896 Theory.hide_types.  Also note that former
  4897 Theory.hide_classes/types/consts are now
  4898 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4899 internalize their arguments!  INCOMPATIBILITY.
  4900 
  4901 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4902 datatype thmref (with constructors Name and NameSelection) instead of
  4903 plain string -- INCOMPATIBILITY;
  4904 
  4905 * Pure: cases produced by proof methods specify options, where NONE
  4906 means to remove case bindings -- INCOMPATIBILITY in
  4907 (RAW_)METHOD_CASES.
  4908 
  4909 * Pure: the following operations retrieve axioms or theorems from a
  4910 theory node or theory hierarchy, respectively:
  4911 
  4912   Theory.axioms_of: theory -> (string * term) list
  4913   Theory.all_axioms_of: theory -> (string * term) list
  4914   PureThy.thms_of: theory -> (string * thm) list
  4915   PureThy.all_thms_of: theory -> (string * thm) list
  4916 
  4917 * Pure: print_tac now outputs the goal through the trace channel.
  4918 
  4919 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4920 Reference Toplevel.debug (default false) controls detailed printing
  4921 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4922 controls execution profiling -- set to 1 for time and 2 for space
  4923 (both increase the runtime).
  4924 
  4925 * Isar session: The initial use of ROOT.ML is now always timed,
  4926 i.e. the log will show the actual process times, in contrast to the
  4927 elapsed wall-clock time that the outer shell wrapper produces.
  4928 
  4929 * Simplifier: improved handling of bound variables (nameless
  4930 representation, avoid allocating new strings).  Simprocs that invoke
  4931 the Simplifier recursively should use Simplifier.inherit_bounds to
  4932 avoid local name clashes.  Failure to do so produces warnings
  4933 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4934 for further details.
  4935 
  4936 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4937 bindings for all theorems stored within a given theory; this may help
  4938 in porting non-Isar theories to Isar ones, while keeping ML proof
  4939 scripts for the time being.
  4940 
  4941 * ML operator HTML.with_charset specifies the charset begin used for
  4942 generated HTML files.  For example:
  4943 
  4944   HTML.with_charset "utf-8" use_thy "Hebrew";
  4945   HTML.with_charset "utf-8" use_thy "Chinese";
  4946 
  4947 
  4948 *** System ***
  4949 
  4950 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4951 isabelle, isatool etc.).
  4952 
  4953 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4954 isatool doc, isatool mkdir, display_drafts etc.).
  4955 
  4956 * isatool usedir: option -f allows specification of the ML file to be
  4957 used by Isabelle; default is ROOT.ML.
  4958 
  4959 * New isatool version outputs the version identifier of the Isabelle
  4960 distribution being used.
  4961 
  4962 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4963 (containing Boolean satisfiability problems) into Isabelle/HOL
  4964 theories.
  4965 
  4966 
  4967 
  4968 New in Isabelle2004 (April 2004)
  4969 --------------------------------
  4970 
  4971 *** General ***
  4972 
  4973 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4974   Replaces linorder.ML.
  4975 
  4976 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4977   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4978   (\<a>...\<z>), are now considered normal letters, and can therefore
  4979   be used anywhere where an ASCII letter (a...zA...Z) has until
  4980   now. COMPATIBILITY: This obviously changes the parsing of some
  4981   terms, especially where a symbol has been used as a binder, say
  4982   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4983   as an identifier.  Fix it by inserting a space around former
  4984   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4985   existing theory and ML files.
  4986 
  4987 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4988 
  4989 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4990   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4991   a normal (but invisible) letter. For multiple letter subscripts repeat
  4992   \<^isub> like this: x\<^isub>1\<^isub>2.
  4993 
  4994 * Pure: There are now sub-/superscripts that can span more than one
  4995   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4996   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4997   superscript. The new control characters are not identifier parts.
  4998 
  4999 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5000   content of "..." to the latex file instead of \isacntrl... . The "..."
  5001   may consist of any printable characters excluding the end bracket >.
  5002 
  5003 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5004   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5005   declare constants "final", which prevents their being given a definition
  5006   later.  It is useful for constants whose behaviour is fixed axiomatically
  5007   rather than definitionally, such as the meta-logic connectives.
  5008 
  5009 * Pure: 'instance' now handles general arities with general sorts
  5010   (i.e. intersections of classes),
  5011 
  5012 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5013   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5014   It can be changed to alter the colors/layout of generated pages.
  5015 
  5016 
  5017 *** Isar ***
  5018 
  5019 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5020   cut_tac, subgoal_tac and thin_tac:
  5021   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5022     locales are no longer forced to write Isar proof scripts.
  5023     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5024     emulations.
  5025   - INCOMPATIBILITY: names of variables to be instantiated may no
  5026     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5027     This is consistent with the instantiation attribute "where".
  5028 
  5029 * Attributes "where" and "of":
  5030   - Now take type variables of instantiated theorem into account when reading
  5031     the instantiation string.  This fixes a bug that caused instantiated
  5032     theorems to have too special types in some circumstances.
  5033   - "where" permits explicit instantiations of type variables.
  5034 
  5035 * Calculation commands "moreover" and "also" no longer interfere with
  5036   current facts ("this"), admitting arbitrary combinations with "then"
  5037   and derived forms.
  5038 
  5039 * Locales:
  5040   - Goal statements involving the context element "includes" no longer
  5041     generate theorems with internal delta predicates (those ending on
  5042     "_axioms") in the premise.
  5043     Resolve particular premise with <locale>.intro to obtain old form.
  5044   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5045     specification and "includes" elements in goal statement.
  5046   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5047     [intro?] and [elim?] (respectively) by default.
  5048   - Experimental command for instantiation of locales in proof contexts:
  5049         instantiate <label>[<attrs>]: <loc>
  5050     Instantiates locale <loc> and adds all its theorems to the current context
  5051     taking into account their attributes.  Label and attrs are optional
  5052     modifiers, like in theorem declarations.  If present, names of
  5053     instantiated theorems are qualified with <label>, and the attributes
  5054     <attrs> are applied after any attributes these theorems might have already.
  5055       If the locale has assumptions, a chained fact of the form
  5056     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5057     are derived.  The command does not support old-style locales declared
  5058     with "locale (open)".
  5059       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5060 
  5061 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5062   (Isar) contexts.
  5063 
  5064 
  5065 *** HOL ***
  5066 
  5067 * Proof import: new image HOL4 contains the imported library from
  5068   the HOL4 system with about 2500 theorems. It is imported by
  5069   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5070   can be used like any other Isabelle image.  See
  5071   HOL/Import/HOL/README for more information.
  5072 
  5073 * Simplifier:
  5074   - Much improved handling of linear and partial orders.
  5075     Reasoners for linear and partial orders are set up for type classes
  5076     "linorder" and "order" respectively, and are added to the default simpset
  5077     as solvers.  This means that the simplifier can build transitivity chains
  5078     to solve goals from the assumptions.
  5079   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5080     of blast or auto after simplification become unnecessary because the goal
  5081     is solved by simplification already.
  5082 
  5083 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5084     all proved in axiomatic type classes for semirings, rings and fields.
  5085 
  5086 * Numerics:
  5087   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5088     now formalized using the Ring_and_Field theory mentioned above.
  5089   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5090     than before, because now they are set up once in a generic manner.
  5091   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5092     Look for the general versions in Ring_and_Field (and Power if they concern
  5093     exponentiation).
  5094 
  5095 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5096 
  5097 * Records:
  5098   - Record types are now by default printed with their type abbreviation
  5099     instead of the list of all field types. This can be configured via
  5100     the reference "print_record_type_abbr".
  5101   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5102     (not enabled by default).
  5103   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5104     EX x. x = sel r to True (not enabled by default).
  5105   - Tactic "record_split_simp_tac" to split and simplify records added.
  5106 
  5107 * 'specification' command added, allowing for definition by
  5108   specification.  There is also an 'ax_specification' command that
  5109   introduces the new constants axiomatically.
  5110 
  5111 * arith(_tac) is now able to generate counterexamples for reals as well.
  5112 
  5113 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5114 
  5115 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5116   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5117 
  5118 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5119   matrix theory to linear programming.
  5120 
  5121 * Unions and Intersections:
  5122   The latex output syntax of UN and INT has been changed
  5123   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5124   i.e. the index formulae has become a subscript.
  5125   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5126 
  5127 * Unions and Intersections over Intervals:
  5128   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5129   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5130   like in normal math, and corresponding versions for < and for intersection.
  5131 
  5132 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5133   lexicographic dictonary ordering has been added as "lexord".
  5134 
  5135 * ML: the legacy theory structures Int and List have been removed. They had
  5136   conflicted with ML Basis Library structures having the same names.
  5137 
  5138 * 'refute' command added to search for (finite) countermodels.  Only works
  5139   for a fragment of HOL.  The installation of an external SAT solver is
  5140   highly recommended.  See "HOL/Refute.thy" for details.
  5141 
  5142 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5143   formulae under an assignment of free variables to random values.
  5144   In contrast to 'refute', it can deal with inductive datatypes,
  5145   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5146   for examples.
  5147 
  5148 
  5149 *** HOLCF ***
  5150 
  5151 * Streams now come with concatenation and are part of the HOLCF image
  5152 
  5153 
  5154 
  5155 New in Isabelle2003 (May 2003)
  5156 ------------------------------
  5157 
  5158 *** General ***
  5159 
  5160 * Provers/simplifier:
  5161 
  5162   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5163     Assumptions are now subject to complete mutual simplification,
  5164     not just from left to right. The simplifier now preserves
  5165     the order of assumptions.
  5166 
  5167     Potential INCOMPATIBILITY:
  5168 
  5169     -- simp sometimes diverges where the old version did
  5170        not, e.g. invoking simp on the goal
  5171 
  5172         [| P (f x); y = x; f x = f y |] ==> Q
  5173 
  5174        now gives rise to the infinite reduction sequence
  5175 
  5176         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5177 
  5178        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5179        kind of problem.
  5180 
  5181     -- Tactics combining classical reasoner and simplification (such as auto)
  5182        are also affected by this change, because many of them rely on
  5183        simp. They may sometimes diverge as well or yield a different numbers
  5184        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5185        in case of problems. Sometimes subsequent calls to the classical
  5186        reasoner will fail because a preceeding call to the simplifier too
  5187        eagerly simplified the goal, e.g. deleted redundant premises.
  5188 
  5189   - The simplifier trace now shows the names of the applied rewrite rules
  5190 
  5191   - You can limit the number of recursive invocations of the simplifier
  5192     during conditional rewriting (where the simplifie tries to solve the
  5193     conditions before applying the rewrite rule):
  5194     ML "simp_depth_limit := n"
  5195     where n is an integer. Thus you can force termination where previously
  5196     the simplifier would diverge.
  5197 
  5198   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5199 
  5200   - No longer aborts on failed congruence proof.  Instead, the
  5201     congruence is ignored.
  5202 
  5203 * Pure: New generic framework for extracting programs from constructive
  5204   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5205   as HOL/Extraction for some case studies.
  5206 
  5207 * Pure: The main goal of the proof state is no longer shown by default, only
  5208 the subgoals. This behaviour is controlled by a new flag.
  5209    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5210 (ML: Proof.show_main_goal).
  5211 
  5212 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5213 rules whose conclusion matches subgoal 1:
  5214       PG menu: Isabelle/Isar -> Show me -> matching rules
  5215 The rules are ordered by how closely they match the subgoal.
  5216 In particular, rules that solve a subgoal outright are displayed first
  5217 (or rather last, the way they are printed).
  5218 (ML: ProofGeneral.print_intros())
  5219 
  5220 * Pure: New flag trace_unify_fail causes unification to print
  5221 diagnostic information (PG: in trace buffer) when it fails. This is
  5222 useful for figuring out why single step proofs like rule, erule or
  5223 assumption failed.
  5224 
  5225 * Pure: Locale specifications now produce predicate definitions
  5226 according to the body of text (covering assumptions modulo local
  5227 definitions); predicate "loc_axioms" covers newly introduced text,
  5228 while "loc" is cumulative wrt. all included locale expressions; the
  5229 latter view is presented only on export into the global theory
  5230 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5231 on the old view without predicates;
  5232 
  5233 * Pure: predefined locales "var" and "struct" are useful for sharing
  5234 parameters (as in CASL, for example); just specify something like
  5235 ``var x + var y + struct M'' as import;
  5236 
  5237 * Pure: improved thms_containing: proper indexing of facts instead of
  5238 raw theorems; check validity of results wrt. current name space;
  5239 include local facts of proof configuration (also covers active
  5240 locales), cover fixed variables in index; may use "_" in term
  5241 specification; an optional limit for the number of printed facts may
  5242 be given (the default is 40);
  5243 
  5244 * Pure: disallow duplicate fact bindings within new-style theory files
  5245 (batch-mode only);
  5246 
  5247 * Provers: improved induct method: assumptions introduced by case
  5248 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5249 the goal statement); "foo" still refers to all facts collectively;
  5250 
  5251 * Provers: the function blast.overloaded has been removed: all constants
  5252 are regarded as potentially overloaded, which improves robustness in exchange
  5253 for slight decrease in efficiency;
  5254 
  5255 * Provers/linorder: New generic prover for transitivity reasoning over
  5256 linear orders.  Note: this prover is not efficient!
  5257 
  5258 * Isar: preview of problems to finish 'show' now produce an error
  5259 rather than just a warning (in interactive mode);
  5260 
  5261 
  5262 *** HOL ***
  5263 
  5264 * arith(_tac)
  5265 
  5266  - Produces a counter example if it cannot prove a goal.
  5267    Note that the counter example may be spurious if the goal is not a formula
  5268    of quantifier-free linear arithmetic.
  5269    In ProofGeneral the counter example appears in the trace buffer.
  5270 
  5271  - Knows about div k and mod k where k is a numeral of type nat or int.
  5272 
  5273  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5274    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5275    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5276 
  5277 * simp's arithmetic capabilities have been enhanced a bit: it now
  5278 takes ~= in premises into account (by performing a case split);
  5279 
  5280 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5281 are distributed over a sum of terms;
  5282 
  5283 * New tactic "trans_tac" and method "trans" instantiate
  5284 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5285 "<=", "<" and "=").
  5286 
  5287 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5288 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5289 
  5290 * 'typedef' command has new option "open" to suppress the set
  5291 definition;
  5292 
  5293 * functions Min and Max on finite sets have been introduced (theory
  5294 Finite_Set);
  5295 
  5296 * attribute [symmetric] now works for relations as well; it turns
  5297 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5298 
  5299 * induct over a !!-quantified statement (say !!x1..xn):
  5300   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5301 
  5302 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5303 %x. None. Warning: empty_def now refers to the previously hidden definition
  5304 of the empty set.
  5305 
  5306 * Algebra: formalization of classical algebra.  Intended as base for
  5307 any algebraic development in Isabelle.  Currently covers group theory
  5308 (up to Sylow's theorem) and ring theory (Universal Property of
  5309 Univariate Polynomials).  Contributions welcome;
  5310 
  5311 * GroupTheory: deleted, since its material has been moved to Algebra;
  5312 
  5313 * Complex: new directory of the complex numbers with numeric constants,
  5314 nonstandard complex numbers, and some complex analysis, standard and
  5315 nonstandard (Jacques Fleuriot);
  5316 
  5317 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5318 
  5319 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5320 Fleuriot);
  5321 
  5322 * Real/HahnBanach: updated and adapted to locales;
  5323 
  5324 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5325 Gray and Kramer);
  5326 
  5327 * UNITY: added the Meier-Sanders theory of progress sets;
  5328 
  5329 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5330 as abstract algorithms, instantiated to the JVM;
  5331 
  5332 * Bali: Java source language formalization. Type system, operational
  5333 semantics, axiomatic semantics. Supported language features:
  5334 classes, interfaces, objects,virtual methods, static methods,
  5335 static/instance fields, arrays, access modifiers, definite
  5336 assignment, exceptions.
  5337 
  5338 
  5339 *** ZF ***
  5340 
  5341 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5342 universe, etc.);
  5343 
  5344 * Main ZF: virtually all theories converted to new-style format;
  5345 
  5346 
  5347 *** ML ***
  5348 
  5349 * Pure: Tactic.prove provides sane interface for internal proofs;
  5350 omits the infamous "standard" operation, so this is more appropriate
  5351 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5352 
  5353 * Pure: improved error reporting of simprocs;
  5354 
  5355 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5356 up simprocs;
  5357 
  5358 
  5359 *** Document preparation ***
  5360 
  5361 * uses \par instead of \\ for line breaks in theory text. This may
  5362 shift some page breaks in large documents. To get the old behaviour
  5363 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5364 
  5365 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5366 other packages
  5367 
  5368 * \<euro> now needs package babel/greek instead of marvosym (which
  5369 broke \Rightarrow)
  5370 
  5371 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5372 textcomp package)
  5373 
  5374 
  5375 
  5376 New in Isabelle2002 (March 2002)
  5377 --------------------------------
  5378 
  5379 *** Document preparation ***
  5380 
  5381 * greatly simplified document preparation setup, including more
  5382 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5383 instructive isatool mkdir; users should basically be able to get
  5384 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5385 users may run a separate document processing stage manually like this:
  5386 "isatool usedir -D output HOL Test && isatool document Test/output";
  5387 
  5388 * theory dependency graph may now be incorporated into documents;
  5389 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5390 with \includegraphics of LaTeX;
  5391 
  5392 * proper spacing of consecutive markup elements, especially text
  5393 blocks after section headings;
  5394 
  5395 * support bold style (for single symbols only), input syntax is like
  5396 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5397 
  5398 * \<bullet> is now output as bold \cdot by default, which looks much
  5399 better in printed text;
  5400 
  5401 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5402 note that these symbols are currently unavailable in Proof General /
  5403 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5404 
  5405 * isatool latex no longer depends on changed TEXINPUTS, instead
  5406 isatool document copies the Isabelle style files to the target
  5407 location;
  5408 
  5409 
  5410 *** Isar ***
  5411 
  5412 * Pure/Provers: improved proof by cases and induction;
  5413   - 'case' command admits impromptu naming of parameters (such as
  5414     "case (Suc n)");
  5415   - 'induct' method divinates rule instantiation from the inductive
  5416     claim; no longer requires excessive ?P bindings for proper
  5417     instantiation of cases;
  5418   - 'induct' method properly enumerates all possibilities of set/type
  5419     rules; as a consequence facts may be also passed through *type*
  5420     rules without further ado;
  5421   - 'induct' method now derives symbolic cases from the *rulified*
  5422     rule (before it used to rulify cases stemming from the internal
  5423     atomized version); this means that the context of a non-atomic
  5424     statement becomes is included in the hypothesis, avoiding the
  5425     slightly cumbersome show "PROP ?case" form;
  5426   - 'induct' may now use elim-style induction rules without chaining
  5427     facts, using ``missing'' premises from the goal state; this allows
  5428     rules stemming from inductive sets to be applied in unstructured
  5429     scripts, while still benefitting from proper handling of non-atomic
  5430     statements; NB: major inductive premises need to be put first, all
  5431     the rest of the goal is passed through the induction;
  5432   - 'induct' proper support for mutual induction involving non-atomic
  5433     rule statements (uses the new concept of simultaneous goals, see
  5434     below);
  5435   - append all possible rule selections, but only use the first
  5436     success (no backtracking);
  5437   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5438   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5439   - added 'print_induct_rules' (covered by help item in recent Proof
  5440     General versions);
  5441   - moved induct/cases attributes to Pure, methods to Provers;
  5442   - generic method setup instantiated for FOL and HOL;
  5443 
  5444 * Pure: support multiple simultaneous goal statements, for example
  5445 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5446 meta-level mechanism, this acts as if several individual goals had
  5447 been stated separately; in particular common proof methods need to be
  5448 repeated in order to cover all claims; note that a single elimination
  5449 step is *not* sufficient to establish the two conjunctions, so this
  5450 fails:
  5451 
  5452   assume "A & B" then have A and B ..   (*".." fails*)
  5453 
  5454 better use "obtain" in situations as above; alternative refer to
  5455 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5456 
  5457 * Pure: proper integration with ``locales''; unlike the original
  5458 version by Florian Kammller, Isar locales package high-level proof
  5459 contexts rather than raw logical ones (e.g. we admit to include
  5460 attributes everywhere); operations on locales include merge and
  5461 rename; support for implicit arguments (``structures''); simultaneous
  5462 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5463 some examples;
  5464 
  5465 * Pure: the following commands have been ``localized'', supporting a
  5466 target locale specification "(in name)": 'lemma', 'theorem',
  5467 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5468 stored both within the locale and at the theory level (exported and
  5469 qualified by the locale name);
  5470 
  5471 * Pure: theory goals may now be specified in ``long'' form, with
  5472 ad-hoc contexts consisting of arbitrary locale elements. for example
  5473 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5474 definitions may be given, too); the result is a meta-level rule with
  5475 the context elements being discharged in the obvious way;
  5476 
  5477 * Pure: new proof command 'using' allows to augment currently used
  5478 facts after a goal statement ('using' is syntactically analogous to
  5479 'apply', but acts on the goal's facts only); this allows chained facts
  5480 to be separated into parts given before and after a claim, as in
  5481 ``from a and b have C using d and e <proof>'';
  5482 
  5483 * Pure: renamed "antecedent" case to "rule_context";
  5484 
  5485 * Pure: new 'judgment' command records explicit information about the
  5486 object-logic embedding (used by several tools internally); no longer
  5487 use hard-wired "Trueprop";
  5488 
  5489 * Pure: added 'corollary' command;
  5490 
  5491 * Pure: fixed 'token_translation' command;
  5492 
  5493 * Pure: removed obsolete 'exported' attribute;
  5494 
  5495 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5496 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5497 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5498 
  5499 * Pure: method 'atomize' presents local goal premises as object-level
  5500 statements (atomic meta-level propositions); setup controlled via
  5501 rewrite rules declarations of 'atomize' attribute; example
  5502 application: 'induct' method with proper rule statements in improper
  5503 proof *scripts*;
  5504 
  5505 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5506 now consider the syntactic context of assumptions, giving a better
  5507 chance to get type-inference of the arguments right (this is
  5508 especially important for locales);
  5509 
  5510 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5511 mode;
  5512 
  5513 * Pure/obtain: the formal conclusion "thesis", being marked as
  5514 ``internal'', may no longer be reference directly in the text;
  5515 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5516 situations;
  5517 
  5518 * Pure: generic 'sym' attribute which declares a rule both as pure
  5519 'elim?' and for the 'symmetric' operation;
  5520 
  5521 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5522 text; the fixed correlation with particular command syntax has been
  5523 discontinued;
  5524 
  5525 * Pure: new method 'rules' is particularly well-suited for proof
  5526 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5527 but often produces more compact proof terms with less detours;
  5528 
  5529 * Pure/Provers/classical: simplified integration with pure rule
  5530 attributes and methods; the classical "intro?/elim?/dest?"
  5531 declarations coincide with the pure ones; the "rule" method no longer
  5532 includes classically swapped intros; "intro" and "elim" methods no
  5533 longer pick rules from the context; also got rid of ML declarations
  5534 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5535 INCOMPATIBILITY;
  5536 
  5537 * Provers/classical: attribute 'swapped' produces classical inversions
  5538 of introduction rules;
  5539 
  5540 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5541 rules instead of full simplifier context; 'iff' attribute handles
  5542 conditional rules;
  5543 
  5544 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5545 
  5546 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5547 "(permissive)" option to recover old behavior;
  5548 
  5549 * HOL: 'inductive' no longer features separate (collective) attributes
  5550 for 'intros' (was found too confusing);
  5551 
  5552 * HOL: properly declared induction rules less_induct and
  5553 wf_induct_rule;
  5554 
  5555 
  5556 *** HOL ***
  5557 
  5558 * HOL: moved over to sane numeral syntax; the new policy is as
  5559 follows:
  5560 
  5561   - 0 and 1 are polymorphic constants, which are defined on any
  5562   numeric type (nat, int, real etc.);
  5563 
  5564   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5565   binary representation internally;
  5566 
  5567   - type nat has special constructor Suc, and generally prefers Suc 0
  5568   over 1::nat and Suc (Suc 0) over 2::nat;
  5569 
  5570 This change may cause significant problems of INCOMPATIBILITY; here
  5571 are some hints on converting existing sources:
  5572 
  5573   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5574   entities, so expressions involving "-" (unary or binary minus) need
  5575   to be spaced properly;
  5576 
  5577   - existing occurrences of "1" may need to be constraint "1::nat" or
  5578   even replaced by Suc 0; similar for old "2";
  5579 
  5580   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5581 
  5582   - remove all special provisions on numerals in proofs;
  5583 
  5584 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5585 representation (depends on bin_arith_simps in the default context);
  5586 
  5587 * HOL: symbolic syntax for x^2 (numeral 2);
  5588 
  5589 * HOL: the class of all HOL types is now called "type" rather than
  5590 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5591 in axclass/classes, instance/arities, and (usually rare) occurrences
  5592 in typings (of consts etc.); internally the class is called
  5593 "HOL.type", ML programs should refer to HOLogic.typeS;
  5594 
  5595 * HOL/record package improvements:
  5596   - new derived operations "fields" to build a partial record section,
  5597     "extend" to promote a fixed record to a record scheme, and
  5598     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5599     declared as simp by default;
  5600   - shared operations ("more", "fields", etc.) now need to be always
  5601     qualified) --- potential INCOMPATIBILITY;
  5602   - removed "make_scheme" operations (use "make" with "extend") --
  5603     INCOMPATIBILITY;
  5604   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5605   - provides cases/induct rules for use with corresponding Isar
  5606     methods (for concrete records, record schemes, concrete more
  5607     parts, and schematic more parts -- in that order);
  5608   - internal definitions directly based on a light-weight abstract
  5609     theory of product types over typedef rather than datatype;
  5610 
  5611 * HOL: generic code generator for generating executable ML code from
  5612 specifications; specific support for HOL constructs such as inductive
  5613 datatypes and sets, as well as recursive functions; can be invoked
  5614 via 'generate_code' theory section;
  5615 
  5616 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5617 
  5618 * HOL: consolidated and renamed several theories.  In particular:
  5619         Ord.thy has been absorbed into HOL.thy
  5620         String.thy has been absorbed into List.thy
  5621 
  5622 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5623 (beware of argument permutation!);
  5624 
  5625 * HOL: linorder_less_split superseded by linorder_cases;
  5626 
  5627 * HOL/List: "nodups" renamed to "distinct";
  5628 
  5629 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5630 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5631   - Ex_def has changed, now need to use some_eq_ex
  5632 
  5633 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5634 in this (rare) case use:
  5635 
  5636   delSWrapper "split_all_tac"
  5637   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5638 
  5639 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5640 MAY FAIL;
  5641 
  5642 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5643 Isabelle's type classes, ^ on functions and relations has too general
  5644 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5645 necessary to attach explicit type constraints;
  5646 
  5647 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5648 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5649 renamed accordingly (eg "compI" -> "rel_compI").
  5650 
  5651 * HOL: syntax translations now work properly with numerals and records
  5652 expressions;
  5653 
  5654 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5655 of "lam" -- INCOMPATIBILITY;
  5656 
  5657 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5658 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5659 renamed "Product_Type.unit";
  5660 
  5661 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5662 
  5663 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5664 the "cases" method);
  5665 
  5666 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5667 Florian Kammller);
  5668 
  5669 * HOL/IMP: updated and converted to new-style theory format; several
  5670 parts turned into readable document, with proper Isar proof texts and
  5671 some explanations (by Gerwin Klein);
  5672 
  5673 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5674 
  5675 * HOL-Hyperreal is now a logic image;
  5676 
  5677 
  5678 *** HOLCF ***
  5679 
  5680 * Isar: consts/constdefs supports mixfix syntax for continuous
  5681 operations;
  5682 
  5683 * Isar: domain package adapted to new-style theory format, e.g. see
  5684 HOLCF/ex/Dnat.thy;
  5685 
  5686 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5687 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5688 lift.induct_tac, always use UU instead of Undef;
  5689 
  5690 * HOLCF/IMP: updated and converted to new-style theory;
  5691 
  5692 
  5693 *** ZF ***
  5694 
  5695 * Isar: proper integration of logic-specific tools and packages,
  5696 including theory commands '(co)inductive', '(co)datatype',
  5697 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5698 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5699 
  5700 * theory Main no longer includes AC; for the Axiom of Choice, base
  5701 your theory on Main_ZFC;
  5702 
  5703 * the integer library now covers quotients and remainders, with many
  5704 laws relating division to addition, multiplication, etc.;
  5705 
  5706 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5707 typeless version of the formalism;
  5708 
  5709 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5710 format;
  5711 
  5712 * ZF/Induct: new directory for examples of inductive definitions,
  5713 including theory Multiset for multiset orderings; converted to
  5714 new-style theory format;
  5715 
  5716 * ZF: many new theorems about lists, ordinals, etc.;
  5717 
  5718 
  5719 *** General ***
  5720 
  5721 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5722 variable proof controls level of detail: 0 = no proofs (only oracle
  5723 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5724 also ref manual for further ML interfaces;
  5725 
  5726 * Pure/axclass: removed obsolete ML interface
  5727 goal_subclass/goal_arity;
  5728 
  5729 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5730 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5731 separate tokens, so expressions involving minus need to be spaced
  5732 properly;
  5733 
  5734 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5735 rather than "infixl" or "infixr";
  5736 
  5737 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5738 sort constraint specifications in type inference; e.g. "x::_::foo"
  5739 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5740 type variable);
  5741 
  5742 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5743 control output of nested => (types); the default behavior is
  5744 "type_brackets";
  5745 
  5746 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5747 tokens into AST constants;
  5748 
  5749 * Pure/syntax: prefer later declarations of translations and print
  5750 translation functions; potential INCOMPATIBILITY: need to reverse
  5751 multiple declarations for same syntax element constant;
  5752 
  5753 * Pure/show_hyps reset by default (in accordance to existing Isar
  5754 practice);
  5755 
  5756 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5757 addSafter;
  5758 
  5759 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5760 as well;
  5761 
  5762 * system: tested support for MacOS X; should be able to get Isabelle +
  5763 Proof General to work in a plain Terminal after installing Poly/ML
  5764 (e.g. from the Isabelle distribution area) and GNU bash alone
  5765 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5766 support requires further installations, e.g. from
  5767 http://fink.sourceforge.net/);
  5768 
  5769 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5770 
  5771 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5772 of 40 MB), cf. ML_OPTIONS;
  5773 
  5774 * system: Proof General keywords specification is now part of the
  5775 Isabelle distribution (see etc/isar-keywords.el);
  5776 
  5777 * system: support for persistent Proof General sessions (refrain from
  5778 outdating all loaded theories on startup); user may create writable
  5779 logic images like this: ``isabelle -q HOL Test'';
  5780 
  5781 * system: smart selection of Isabelle process versus Isabelle
  5782 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5783 run both "isabelle" and "Isabelle" even if file names are badly
  5784 damaged (executable inspects the case of the first letter of its own
  5785 name); added separate "isabelle-process" and "isabelle-interface";
  5786 
  5787 * system: refrain from any attempt at filtering input streams; no
  5788 longer support ``8bit'' encoding of old isabelle font, instead proper
  5789 iso-latin characters may now be used; the related isatools
  5790 "symbolinput" and "nonascii" have disappeared as well;
  5791 
  5792 * system: removed old "xterm" interface (the print modes "xterm" and
  5793 "xterm_color" are still available for direct use in a suitable
  5794 terminal);
  5795 
  5796 
  5797 
  5798 New in Isabelle99-2 (February 2001)
  5799 -----------------------------------
  5800 
  5801 *** Overview of INCOMPATIBILITIES ***
  5802 
  5803 * HOL: please note that theories in the Library and elsewhere often use the
  5804 new-style (Isar) format; to refer to their theorems in an ML script you must
  5805 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5806 
  5807 * HOL: inductive package no longer splits induction rule aggressively,
  5808 but only as far as specified by the introductions given; the old
  5809 format may be recovered via ML function complete_split_rule or attribute
  5810 'split_rule (complete)';
  5811 
  5812 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5813 gfp_Tarski to gfp_unfold;
  5814 
  5815 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5816 
  5817 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5818 relation); infix "^^" has been renamed "``"; infix "``" has been
  5819 renamed "`"; "univalent" has been renamed "single_valued";
  5820 
  5821 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5822 operation;
  5823 
  5824 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5825 
  5826 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5827 
  5828 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5829 consequence, it is no longer monotonic wrt. the local goal context
  5830 (which is now passed through the inductive cases);
  5831 
  5832 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5833 \<gg> to \<ggreater>;
  5834 
  5835 
  5836 *** Document preparation ***
  5837 
  5838 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5839 available: are "it" for near math-mode best-style output, "sl" for
  5840 slanted text style, and "tt" for plain type-writer; if no
  5841 \isabellestyle command is given, output is according to slanted
  5842 type-writer);
  5843 
  5844 * support sub/super scripts (for single symbols only), input syntax is
  5845 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5846 
  5847 * some more standard symbols; see Appendix A of the system manual for
  5848 the complete list of symbols defined in isabellesym.sty;
  5849 
  5850 * improved isabelle style files; more abstract symbol implementation
  5851 (should now use \isamath{...} and \isatext{...} in custom symbol
  5852 definitions);
  5853 
  5854 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5855 state; Note that presentation of goal states does not conform to
  5856 actual human-readable proof documents.  Please do not include goal
  5857 states into document output unless you really know what you are doing!
  5858 
  5859 * proper indentation of antiquoted output with proportional LaTeX
  5860 fonts;
  5861 
  5862 * no_document ML operator temporarily disables LaTeX document
  5863 generation;
  5864 
  5865 * isatool unsymbolize tunes sources for plain ASCII communication;
  5866 
  5867 
  5868 *** Isar ***
  5869 
  5870 * Pure: Isar now suffers initial goal statements to contain unbound
  5871 schematic variables (this does not conform to actual readable proof
  5872 documents, due to unpredictable outcome and non-compositional proof
  5873 checking); users who know what they are doing may use schematic goals
  5874 for Prolog-style synthesis of proven results;
  5875 
  5876 * Pure: assumption method (an implicit finishing) now handles actual
  5877 rules as well;
  5878 
  5879 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5880 initial goal, declare "that" only as Pure intro (only for single
  5881 steps); the "that" rule assumption may now be involved in implicit
  5882 finishing, thus ".." becomes a feasible for trivial obtains;
  5883 
  5884 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5885 instance proofs may be performed by "..";
  5886 
  5887 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5888 statements as well;
  5889 
  5890 * Pure: more robust selection of calculational rules;
  5891 
  5892 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5893 rule (as well as the assumption rule);
  5894 
  5895 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5896 lemmas, using the graph browser tool;
  5897 
  5898 * Pure: predict failure of "show" in interactive mode;
  5899 
  5900 * Pure: 'thms_containing' now takes actual terms as arguments;
  5901 
  5902 * HOL: improved method 'induct' --- now handles non-atomic goals
  5903 (potential INCOMPATIBILITY); tuned error handling;
  5904 
  5905 * HOL: cases and induct rules now provide explicit hints about the
  5906 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5907 any remaining facts are inserted into the goal verbatim;
  5908 
  5909 * HOL: local contexts (aka cases) may now contain term bindings as
  5910 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5911 the result to be shown in each case;
  5912 
  5913 * HOL: added 'recdef_tc' command;
  5914 
  5915 * isatool convert assists in eliminating legacy ML scripts;
  5916 
  5917 
  5918 *** HOL ***
  5919 
  5920 * HOL/Library: a collection of generic theories to be used together
  5921 with main HOL; the theory loader path already includes this directory
  5922 by default; the following existing theories have been moved here:
  5923 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5924 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5925 
  5926 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5927 modelling and verification task performed in Isabelle/HOL +
  5928 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5929 
  5930 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5931 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5932 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5933 'domain', this makes the theory consistent with mathematical
  5934 literature;
  5935 
  5936 * HOL basics: added overloaded operations "inverse" and "divide"
  5937 (infix "/"), syntax for generic "abs" operation, generic summation
  5938 operator \<Sum>;
  5939 
  5940 * HOL/typedef: simplified package, provide more useful rules (see also
  5941 HOL/subset.thy);
  5942 
  5943 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5944 now expressed as a proper nested rule (old-style tactic scripts may
  5945 require atomize_strip_tac to cope with non-atomic premises);
  5946 
  5947 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5948 to "split_conv" (old name still available for compatibility);
  5949 
  5950 * HOL: improved concrete syntax for strings (e.g. allows translation
  5951 rules with string literals);
  5952 
  5953 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5954  and Fleuriot's mechanization of analysis, including the transcendental
  5955  functions for the reals;
  5956 
  5957 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5958 
  5959 
  5960 *** CTT ***
  5961 
  5962 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5963 "lam" is displayed as TWO lambda-symbols
  5964 
  5965 * CTT: theory Main now available, containing everything (that is, Bool
  5966 and Arith);
  5967 
  5968 
  5969 *** General ***
  5970 
  5971 * Pure: the Simplifier has been implemented properly as a derived rule
  5972 outside of the actual kernel (at last!); the overall performance
  5973 penalty in practical applications is about 50%, while reliability of
  5974 the Isabelle inference kernel has been greatly improved;
  5975 
  5976 * print modes "brackets" and "no_brackets" control output of nested =>
  5977 (types) and ==> (props); the default behaviour is "brackets";
  5978 
  5979 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5980 as assumptions as well;
  5981 
  5982 * system: support Poly/ML 4.0;
  5983 
  5984 * system: isatool install handles KDE version 1 or 2;
  5985 
  5986 
  5987 
  5988 New in Isabelle99-1 (October 2000)
  5989 ----------------------------------
  5990 
  5991 *** Overview of INCOMPATIBILITIES ***
  5992 
  5993 * HOL: simplification of natural numbers is much changed; to partly
  5994 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5995 issue the following ML commands:
  5996 
  5997   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5998   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5999 
  6000 * HOL: simplification no longer dives into case-expressions; this is
  6001 controlled by "t.weak_case_cong" for each datatype t;
  6002 
  6003 * HOL: nat_less_induct renamed to less_induct;
  6004 
  6005 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6006 fixsome to patch .thy and .ML sources automatically;
  6007 
  6008   select_equality  -> some_equality
  6009   select_eq_Ex     -> some_eq_ex
  6010   selectI2EX       -> someI2_ex
  6011   selectI2         -> someI2
  6012   selectI          -> someI
  6013   select1_equality -> some1_equality
  6014   Eps_sym_eq       -> some_sym_eq_trivial
  6015   Eps_eq           -> some_eq_trivial
  6016 
  6017 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6018 
  6019 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6020 instead);
  6021 
  6022 * HOL: the recursion equations generated by 'recdef' are now called
  6023 f.simps instead of f.rules;
  6024 
  6025 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6026 
  6027 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6028 sometimes be needed;
  6029 
  6030 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6031 
  6032 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6033 
  6034 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6035 product is now "<*>" instead of "Times"; the lexicographic product is
  6036 now "<*lex*>" instead of "**";
  6037 
  6038 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6039 of main HOL, but was unused); better use HOL's datatype package;
  6040 
  6041 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6042 the old syntax may be recovered as follows:
  6043 
  6044   syntax (symbols)
  6045     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6046       (infixl "\\<oplus>" 100)
  6047 
  6048 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6049 
  6050 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6051 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6052 internally;
  6053 
  6054 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6055 changed from A/r to A//r;
  6056 
  6057 * ZF: new treatment of arithmetic (nat & int) may break some old
  6058 proofs;
  6059 
  6060 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6061 rulify -> rule_format, elimify -> elim_format, ...);
  6062 
  6063 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6064 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6065 should have to change intro!! to intro? only); replaced "delrule" by
  6066 "rule del";
  6067 
  6068 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6069 
  6070 * Provers: strengthened force_tac by using new first_best_tac;
  6071 
  6072 * LaTeX document preparation: several changes of isabelle.sty (see
  6073 lib/texinputs);
  6074 
  6075 
  6076 *** Document preparation ***
  6077 
  6078 * formal comments (text blocks etc.) in new-style theories may now
  6079 contain antiquotations of thm/prop/term/typ/text to be presented
  6080 according to latex print mode; concrete syntax is like this:
  6081 @{term[show_types] "f(x) = a + x"};
  6082 
  6083 * isatool mkdir provides easy setup of Isabelle session directories,
  6084 including proper document sources;
  6085 
  6086 * generated LaTeX sources are now deleted after successful run
  6087 (isatool document -c); may retain a copy somewhere else via -D option
  6088 of isatool usedir;
  6089 
  6090 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6091 style files, achieving self-contained LaTeX sources and simplifying
  6092 LaTeX debugging;
  6093 
  6094 * old-style theories now produce (crude) LaTeX output as well;
  6095 
  6096 * browser info session directories are now self-contained (may be put
  6097 on WWW server seperately); improved graphs of nested sessions; removed
  6098 graph for 'all sessions';
  6099 
  6100 * several improvements in isabelle style files; \isabellestyle{it}
  6101 produces fake math mode output; \isamarkupheader is now \section by
  6102 default; see lib/texinputs/isabelle.sty etc.;
  6103 
  6104 
  6105 *** Isar ***
  6106 
  6107 * Isar/Pure: local results and corresponding term bindings are now
  6108 subject to Hindley-Milner polymorphism (similar to ML); this
  6109 accommodates incremental type-inference very nicely;
  6110 
  6111 * Isar/Pure: new derived language element 'obtain' supports
  6112 generalized existence reasoning;
  6113 
  6114 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6115 support accumulation of results, without applying any rules yet;
  6116 useful to collect intermediate results without explicit name
  6117 references, and for use with transitivity rules with more than 2
  6118 premises;
  6119 
  6120 * Isar/Pure: scalable support for case-analysis type proofs: new
  6121 'case' language element refers to local contexts symbolically, as
  6122 produced by certain proof methods; internally, case names are attached
  6123 to theorems as "tags";
  6124 
  6125 * Isar/Pure: theory command 'hide' removes declarations from
  6126 class/type/const name spaces;
  6127 
  6128 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6129 indicate potential overloading;
  6130 
  6131 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6132 
  6133 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6134 "{a,b,c}" instead of {a,b,c};
  6135 
  6136 * Isar/Pure now provides its own version of intro/elim/dest
  6137 attributes; useful for building new logics, but beware of confusion
  6138 with the version in Provers/classical;
  6139 
  6140 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6141 case name 'antecedent';
  6142 
  6143 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6144 to the current context is now done automatically);
  6145 
  6146 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6147 for definining proof methods in ML;
  6148 
  6149 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6150 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6151 most cases, one should have to change intro!! to intro? only);
  6152 replaced "delrule" by "rule del";
  6153 
  6154 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6155 'symmetric' attribute (the latter supercedes [RS sym]);
  6156 
  6157 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6158 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6159 well (including splits);
  6160 
  6161 * Isar/Provers: Simplifier and Classical methods now support all kind
  6162 of modifiers used in the past, including 'cong', 'iff', etc.
  6163 
  6164 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6165 of Simplifier and Classical reasoner);
  6166 
  6167 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6168 now support named cases; major packages (inductive, datatype, primrec,
  6169 recdef) support case names and properly name parameters;
  6170 
  6171 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6172 monotonicity conditions are extracted to be proven at end of
  6173 calculations;
  6174 
  6175 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6176 method anyway;
  6177 
  6178 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6179 split_if split_if_asm; datatype package provides theorems foo.splits =
  6180 foo.split foo.split_asm for each datatype;
  6181 
  6182 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6183 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6184 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6185 use "(cases (simplified))" method in proper proof texts);
  6186 
  6187 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6188 
  6189 * Isar: names of theorems etc. may be natural numbers as well;
  6190 
  6191 * Isar: 'pr' command: optional arguments for goals_limit and
  6192 ProofContext.prems_limit; no longer prints theory contexts, but only
  6193 proof states;
  6194 
  6195 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6196 additional print modes to be specified; e.g. "pr(latex)" will print
  6197 proof state according to the Isabelle LaTeX style;
  6198 
  6199 * Isar: improved support for emulating tactic scripts, including proof
  6200 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6201 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6202 (for HOL datatypes);
  6203 
  6204 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6205 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6206 'proof method scripts' have to be in depth-first order;
  6207 
  6208 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6209 
  6210 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6211 should instead use individual commands for printing items
  6212 (print_commands, print_methods etc.);
  6213 
  6214 * Isar: added 'nothing' --- the empty list of theorems;
  6215 
  6216 
  6217 *** HOL ***
  6218 
  6219 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6220 corresponding virtual machine and a specification of its bytecode
  6221 verifier and a lightweight bytecode verifier, including proofs of
  6222 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6223 Cornelia Pusch (see also the homepage of project Bali at
  6224 http://isabelle.in.tum.de/Bali/);
  6225 
  6226 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6227 Clemens Ballarin;
  6228 
  6229 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6230 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6231 Rasmussen;
  6232 
  6233 * HOL/Lattice: fundamental concepts of lattice theory and order
  6234 structures, including duals, properties of bounds versus algebraic
  6235 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6236 Theorem for complete lattices etc.; may also serve as a demonstration