NEWS
author krauss
Fri Oct 29 21:41:14 2010 +0200 (2010-10-29)
changeset 40288 520199d8b66e
parent 40253 f99ec71de82d
child 40291 012ed4426fda
child 40294 edec5213042b
permissions -rw-r--r--
added rule let_mono
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Significantly improved Isabelle/Isar implementation manual.
    10 
    11 * Explicit treatment of UTF8 sequences as Isabelle symbols, such that
    12 a Unicode character is treated as a single symbol, not a sequence of
    13 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    14 contain symbols without further backslash escapes, Unicode can now be
    15 used here as well.  Recall that Symbol.explode in ML provides a
    16 consistent view on symbols, while raw explode (or String.explode)
    17 merely give a byte-oriented representation.
    18 
    19 * Theory loading: only the master source file is looked-up in the
    20 implicit load path, all other files are addressed relatively to its
    21 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    22 
    23 * Special treatment of ML file names has been discontinued.
    24 Historically, optional extensions .ML or .sml were added on demand --
    25 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    26 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    27 
    28 * Various options that affect pretty printing etc. are now properly
    29 handled within the context via configuration options, instead of
    30 unsynchronized references.  There are both ML Config.T entities and
    31 Isar declaration attributes to access these.
    32 
    33   ML (Config.T)                 Isar (attribute)
    34 
    35   eta_contract                  eta_contract
    36   show_brackets                 show_brackets
    37   show_sorts                    show_sorts
    38   show_types                    show_types
    39   show_question_marks           show_question_marks
    40   show_consts                   show_consts
    41 
    42   Syntax.ambiguity_level        syntax_ambiguity_level
    43 
    44   Goal_Display.goals_limit      goals_limit
    45   Goal_Display.show_main_goal   show_main_goal
    46 
    47   Thy_Output.display            thy_output_display
    48   Thy_Output.quotes             thy_output_quotes
    49   Thy_Output.indent             thy_output_indent
    50   Thy_Output.source             thy_output_source
    51   Thy_Output.break              thy_output_break
    52 
    53 Note that corresponding "..._default" references in ML may be only
    54 changed globally at the ROOT session setup, but *not* within a theory.
    55 
    56 
    57 *** Pure ***
    58 
    59 * Interpretation command 'interpret' accepts a list of equations like
    60 'interpretation' does.
    61 
    62 * Diagnostic command 'print_interps' prints interpretations in proofs
    63 in addition to interpretations in theories.
    64 
    65 * Discontinued obsolete 'global' and 'local' commands to manipulate
    66 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
    67 Sign.root_path and Sign.local_path may be applied directly where this
    68 feature is still required for historical reasons.
    69 
    70 * Discontinued ancient 'constdefs' command.  INCOMPATIBILITY, use
    71 'definition' instead.
    72 
    73 * Document antiquotations @{class} and @{type} for printing classes
    74 and type constructors.
    75 
    76 
    77 *** HOL ***
    78 
    79 * Quickcheck now has a configurable time limit which is set to 30 seconds
    80 by default. This can be changed by adding [timeout = n] to the quickcheck
    81 command. The time limit for auto quickcheck is still set independently,
    82 by default to 5 seconds.
    83 
    84 * New command 'partial_function' provides basic support for recursive
    85 function definitions over complete partial orders. Concrete instances
    86 are provided for i) the option type, ii) tail recursion on arbitrary
    87 types, and iii) the heap monad of Imperative_HOL. See
    88 HOL/ex/Fundefs.thy and HOL/Imperative_HOL/ex/Linked_Lists.thy for
    89 examples.
    90 
    91 * Predicates `distinct` and `sorted` now defined inductively, with nice
    92 induction rules.  INCOMPATIBILITY: former distinct.simps and sorted.simps
    93 now named distinct_simps and sorted_simps.
    94 
    95 * Constant `contents` renamed to `the_elem`, to free the generic name
    96 contents for other uses.  INCOMPATIBILITY.
    97 
    98 * Dropped old primrec package.  INCOMPATIBILITY.
    99 
   100 * Improved infrastructure for term evaluation using code generator
   101 techniques, in particular static evaluation conversions.
   102 
   103 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   104  
   105 * Renamed lemmas:
   106   expand_fun_eq -> fun_eq_iff
   107   expand_set_eq -> set_eq_iff
   108   set_ext -> set_eqI
   109  INCOMPATIBILITY.
   110 
   111 * Renamed lemma list: nat_number -> eval_nat_numeral
   112 
   113 * Renamed class eq and constant eq (for code generation) to class equal
   114 and constant equal, plus renaming of related facts and various tuning.
   115 INCOMPATIBILITY.
   116 
   117 * Scala (2.8 or higher) has been added to the target languages of
   118 the code generator.
   119 
   120 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   121 
   122 * Removed output syntax "'a ~=> 'b" for "'a => 'b option". INCOMPATIBILITY.
   123 
   124 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
   125 canonical names for instance definitions for functions; various improvements.
   126 INCOMPATIBILITY.
   127 
   128 * Records: logical foundation type for records do not carry a '_type' suffix
   129 any longer.  INCOMPATIBILITY.
   130 
   131 * Code generation for records: more idiomatic representation of record types.
   132 Warning: records are not covered by ancient SML code generation any longer.
   133 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
   134 helps to succeed then:
   135 
   136   record 'a foo = ...
   137   ...
   138   rep_datatype foo_ext ...
   139 
   140 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   141 INCOMPATIBILITY.
   142 
   143 * Quickcheck in locales considers interpretations of that locale for
   144 counter example search.
   145 
   146 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   147 in Library/State_Monad has been changed to avoid ambiguities.
   148 INCOMPATIBILITY.
   149 
   150 * Code generator: export_code without explicit file declaration prints
   151 to standard output.  INCOMPATIBILITY.
   152 
   153 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   154 respectively.  INCOMPATIBILITY.
   155 
   156 * Constant "split" has been merged with constant "prod_case";  names
   157 of ML functions, facts etc. involving split have been retained so far,
   158 though.  INCOMPATIBILITY.
   159 
   160 * Dropped old infix syntax "mem" for List.member;  use "in set"
   161 instead.  INCOMPATIBILITY.
   162 
   163 * Refactoring of code-generation specific operations in List.thy
   164 
   165   constants
   166     null ~> List.null
   167 
   168   facts
   169     mem_iff ~> member_def
   170     null_empty ~> null_def
   171 
   172 INCOMPATIBILITY.  Note that these were not suppossed to be used
   173 regularly unless for striking reasons;  their main purpose was code
   174 generation.
   175 
   176 * Some previously unqualified names have been qualified:
   177 
   178   types
   179     bool ~> HOL.bool
   180     nat ~> Nat.nat
   181 
   182   constants
   183     Trueprop ~> HOL.Trueprop
   184     True ~> HOL.True
   185     False ~> HOL.False
   186     op & ~> HOL.conj
   187     op | ~> HOL.disj
   188     op --> ~> HOL.implies
   189     op = ~> HOL.eq
   190     Not ~> HOL.Not
   191     The ~> HOL.The
   192     All ~> HOL.All
   193     Ex ~> HOL.Ex
   194     Ex1 ~> HOL.Ex1
   195     Let ~> HOL.Let
   196     If ~> HOL.If
   197     Ball ~> Set.Ball
   198     Bex ~> Set.Bex
   199     Suc ~> Nat.Suc
   200     Pair ~> Product_Type.Pair
   201     fst ~> Product_Type.fst
   202     snd ~> Product_Type.snd
   203     curry ~> Product_Type.curry
   204     op : ~> Set.member
   205     Collect ~> Set.Collect
   206 
   207 INCOMPATIBILITY.
   208 
   209 * Removed simplifier congruence rule of "prod_case", as has for long
   210 been the case with "split".  INCOMPATIBILITY.
   211 
   212 * Datatype package: theorems generated for executable equality
   213 (class eq) carry proper names and are treated as default code
   214 equations.
   215 
   216 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   217 INCOMPATIBILITY.
   218 
   219 * List.thy: use various operations from the Haskell prelude when
   220 generating Haskell code.
   221 
   222 * Multiset.thy: renamed empty_idemp -> empty_neutral
   223 
   224 * code_simp.ML and method code_simp: simplification with rules determined
   225 by code generator.
   226 
   227 * code generator: do not print function definitions for case
   228 combinators any longer.
   229 
   230 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   231 theorems are now stated in terms of euclidean spaces instead of finite
   232 cartesian products.
   233 
   234   types
   235     real ^ 'n ~>  'a::real_vector
   236               ~>  'a::euclidean_space
   237               ~>  'a::ordered_euclidean_space
   238         (depends on your needs)
   239 
   240   constants
   241      _ $ _        ~> _ $$ _
   242      \<chi> x. _  ~> \<chi>\<chi> x. _
   243      CARD('n)     ~> DIM('a)
   244 
   245 Also note that the indices are now natural numbers and not from some finite
   246 type. Finite cartesian products of euclidean spaces, products of euclidean
   247 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   248 
   249 INCOMPATIBILITY.
   250 
   251 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   252 as value for measures. Introduces Lebesgue Measure based on the integral in
   253 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   254 spaces.
   255 
   256  INCOMPATIBILITY.
   257 
   258 * Inductive package: offers new command "inductive_simps" to automatically
   259 derive instantiated and simplified equations for inductive predicates,
   260 similar to inductive_cases.
   261 
   262 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   263 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   264 The theorems bij_def and surj_def are unchanged.
   265 
   266 * Function package: .psimps rules are no longer implicitly declared [simp].
   267 INCOMPATIBILITY.
   268 
   269 * Weaker versions of the "meson" and "metis" proof methods are now available in
   270   "HOL-Plain", without dependency on "Hilbert_Choice". The proof methods become
   271   more powerful after "Hilbert_Choice" is loaded in "HOL-Main".
   272 
   273 * MESON: Renamed lemmas:
   274   meson_not_conjD ~> Meson.not_conjD
   275   meson_not_disjD ~> Meson.not_disjD
   276   meson_not_notD ~> Meson.not_notD
   277   meson_not_allD ~> Meson.not_allD
   278   meson_not_exD ~> Meson.not_exD
   279   meson_imp_to_disjD ~> Meson.imp_to_disjD
   280   meson_not_impD ~> Meson.not_impD
   281   meson_iff_to_disjD ~> Meson.iff_to_disjD
   282   meson_not_iffD ~> Meson.not_iffD
   283   meson_not_refl_disj_D ~> Meson.not_refl_disj_D
   284   meson_conj_exD1 ~> Meson.conj_exD1
   285   meson_conj_exD2 ~> Meson.conj_exD2
   286   meson_disj_exD ~> Meson.disj_exD
   287   meson_disj_exD1 ~> Meson.disj_exD1
   288   meson_disj_exD2 ~> Meson.disj_exD2
   289   meson_disj_assoc ~> Meson.disj_assoc
   290   meson_disj_comm ~> Meson.disj_comm
   291   meson_disj_FalseD1 ~> Meson.disj_FalseD1
   292   meson_disj_FalseD2 ~> Meson.disj_FalseD2
   293 INCOMPATIBILITY.
   294 
   295 * Auto Solve: Renamed "Auto Solve Direct". The tool is now available manually as
   296   "solve_direct".
   297 
   298 * Sledgehammer:
   299   - Renamed lemmas:
   300     COMBI_def ~> Meson.COMBI_def
   301     COMBK_def ~> Meson.COMBK_def
   302     COMBB_def ~> Meson.COMBB_def
   303     COMBC_def ~> Meson.COMBC_def
   304     COMBS_def ~> Meson.COMBS_def
   305     abs_I ~> Meson.abs_I
   306     abs_K ~> Meson.abs_K
   307     abs_B ~> Meson.abs_B
   308     abs_C ~> Meson.abs_C
   309     abs_S ~> Meson.abs_S
   310     INCOMPATIBILITY.
   311   - Renamed commands:
   312     sledgehammer atp_info ~> sledgehammer running_provers
   313     sledgehammer atp_kill ~> sledgehammer kill_provers
   314     sledgehammer available_atps ~> sledgehammer available_provers
   315     INCOMPATIBILITY.
   316   - Renamed options:
   317     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   318     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   319     INCOMPATIBILITY.
   320 
   321 * Changed SMT configuration options:
   322   - Renamed:
   323     z3_proofs ~> smt_oracle (with swapped semantics)
   324     z3_trace_assms ~> smt_trace_used_facts
   325     INCOMPATIBILITY.
   326   - Added:
   327     cvc3_options
   328     yices_options
   329     smt_datatypes
   330 
   331 *** FOL ***
   332 
   333 * All constant names are now qualified.  INCOMPATIBILITY.
   334 
   335 
   336 *** ZF ***
   337 
   338 * All constant names are now qualified.  INCOMPATIBILITY.
   339 
   340 
   341 *** ML ***
   342 
   343 * Antiquotation @{assert} inlines a function bool -> unit that raises
   344 Fail if the argument is false.  Due to inlining the source position of
   345 failed assertions is included in the error output.
   346 
   347 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   348 text is in practice always evaluated with a stable theory checkpoint.
   349 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   350 
   351 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   352 meaning.
   353 
   354 * Renamed structure PureThy to Pure_Thy and moved most of its
   355 operations to structure Global_Theory, to emphasize that this is
   356 rarely-used global-only stuff.
   357 
   358 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   359 instead (or tracing for high-volume output).
   360 
   361 * Configuration option show_question_marks only affects regular pretty
   362 printing of types and terms, not raw Term.string_of_vname.
   363 
   364 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   365 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   366 @{thms} for most purposes.
   367 
   368 * ML structure Unsynchronized never opened, not even in Isar
   369 interaction mode as before.  Old Unsynchronized.set etc. have been
   370 discontinued -- use plain := instead.  This should be *rare* anyway,
   371 since modern tools always work via official context data, notably
   372 configuration options.
   373 
   374 * ML antiquotations @{theory} and @{theory_ref} refer to named
   375 theories from the ancestry of the current context, not any accidental
   376 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   377 change in semantics.
   378 
   379 * Parallel and asynchronous execution requires special care concerning
   380 interrupts.  Structure Exn provides some convenience functions that
   381 avoid working directly with raw Interrupt.  User code must not absorb
   382 interrupts -- intermediate handling (for cleanup etc.) needs to be
   383 followed by re-raising of the original exception.  Another common
   384 source of mistakes are "handle _" patterns, which make the meaning of
   385 the program subject to physical effects of the environment.
   386 
   387 
   388 *** System ***
   389 
   390 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   391 
   392 
   393 
   394 New in Isabelle2009-2 (June 2010)
   395 ---------------------------------
   396 
   397 *** General ***
   398 
   399 * Authentic syntax for *all* logical entities (type classes, type
   400 constructors, term constants): provides simple and robust
   401 correspondence between formal entities and concrete syntax.  Within
   402 the parse tree / AST representations, "constants" are decorated by
   403 their category (class, type, const) and spelled out explicitly with
   404 their full internal name.
   405 
   406 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   407 and translations (translation rules and translation functions in ML).
   408 Some hints on upgrading:
   409 
   410   - Many existing uses of 'syntax' and 'translations' can be replaced
   411     by more modern 'type_notation', 'notation' and 'abbreviation',
   412     which are independent of this issue.
   413 
   414   - 'translations' require markup within the AST; the term syntax
   415     provides the following special forms:
   416 
   417       CONST c   -- produces syntax version of constant c from context
   418       XCONST c  -- literally c, checked as constant from context
   419       c         -- literally c, if declared by 'syntax'
   420 
   421     Plain identifiers are treated as AST variables -- occasionally the
   422     system indicates accidental variables via the error "rhs contains
   423     extra variables".
   424 
   425     Type classes and type constructors are marked according to their
   426     concrete syntax.  Some old translations rules need to be written
   427     for the "type" category, using type constructor application
   428     instead of pseudo-term application of the default category
   429     "logic".
   430 
   431   - 'parse_translation' etc. in ML may use the following
   432     antiquotations:
   433 
   434       @{class_syntax c}   -- type class c within parse tree / AST
   435       @{term_syntax c}    -- type constructor c within parse tree / AST
   436       @{const_syntax c}   -- ML version of "CONST c" above
   437       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   438 
   439   - Literal types within 'typed_print_translations', i.e. those *not*
   440     represented as pseudo-terms are represented verbatim.  Use @{class
   441     c} or @{type_name c} here instead of the above syntax
   442     antiquotations.
   443 
   444 Note that old non-authentic syntax was based on unqualified base
   445 names, so all of the above "constant" names would coincide.  Recall
   446 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   447 diagnose syntax problems.
   448 
   449 * Type constructors admit general mixfix syntax, not just infix.
   450 
   451 * Concrete syntax may be attached to local entities without a proof
   452 body, too.  This works via regular mixfix annotations for 'fix',
   453 'def', 'obtain' etc. or via the explicit 'write' command, which is
   454 similar to the 'notation' command in theory specifications.
   455 
   456 * Discontinued unnamed infix syntax (legacy feature for many years) --
   457 need to specify constant name and syntax separately.  Internal ML
   458 datatype constructors have been renamed from InfixName to Infix etc.
   459 Minor INCOMPATIBILITY.
   460 
   461 * Schematic theorem statements need to be explicitly markup as such,
   462 via commands 'schematic_lemma', 'schematic_theorem',
   463 'schematic_corollary'.  Thus the relevance of the proof is made
   464 syntactically clear, which impacts performance in a parallel or
   465 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   466 
   467 * Use of cumulative prems via "!" in some proof methods has been
   468 discontinued (old legacy feature).
   469 
   470 * References 'trace_simp' and 'debug_simp' have been replaced by
   471 configuration options stored in the context. Enabling tracing (the
   472 case of debugging is similar) in proofs works via
   473 
   474   using [[trace_simp = true]]
   475 
   476 Tracing is then active for all invocations of the simplifier in
   477 subsequent goal refinement steps. Tracing may also still be enabled or
   478 disabled via the ProofGeneral settings menu.
   479 
   480 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   481 'hide_fact' replace the former 'hide' KIND command.  Minor
   482 INCOMPATIBILITY.
   483 
   484 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   485 more efficient than combinations with -q1 or -q2.
   486 
   487 
   488 *** Pure ***
   489 
   490 * Proofterms record type-class reasoning explicitly, using the
   491 "unconstrain" operation internally.  This eliminates all sort
   492 constraints from a theorem and proof, introducing explicit
   493 OFCLASS-premises.  On the proof term level, this operation is
   494 automatically applied at theorem boundaries, such that closed proofs
   495 are always free of sort constraints.  INCOMPATIBILITY for tools that
   496 inspect proof terms.
   497 
   498 * Local theory specifications may depend on extra type variables that
   499 are not present in the result type -- arguments TYPE('a) :: 'a itself
   500 are added internally.  For example:
   501 
   502   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   503 
   504 * Predicates of locales introduced by classes carry a mandatory
   505 "class" prefix.  INCOMPATIBILITY.
   506 
   507 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   508 
   509 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   510 'class' instead.
   511 
   512 * Command 'code_reflect' allows to incorporate generated ML code into
   513 runtime environment; replaces immature code_datatype antiquotation.
   514 INCOMPATIBILITY.
   515 
   516 * Code generator: simple concept for abstract datatypes obeying
   517 invariants.
   518 
   519 * Code generator: details of internal data cache have no impact on the
   520 user space functionality any longer.
   521 
   522 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   523 subgoals.  This is more appropriate for interpretations with 'where'.
   524 INCOMPATIBILITY.
   525 
   526 * Command 'example_proof' opens an empty proof body.  This allows to
   527 experiment with Isar, without producing any persistent result.
   528 
   529 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   530 within a local theory context, with explicit checking of the
   531 constructors involved (in contrast to the raw 'syntax' versions).
   532 
   533 * Commands 'types' and 'typedecl' now work within a local theory
   534 context -- without introducing dependencies on parameters or
   535 assumptions, which is not possible in Isabelle/Pure.
   536 
   537 * Command 'defaultsort' has been renamed to 'default_sort', it works
   538 within a local theory context.  Minor INCOMPATIBILITY.
   539 
   540 
   541 *** HOL ***
   542 
   543 * Command 'typedef' now works within a local theory context -- without
   544 introducing dependencies on parameters or assumptions, which is not
   545 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   546 contain multiple interpretations of local typedefs (with different
   547 non-emptiness proofs), even in a global theory context.
   548 
   549 * New package for quotient types.  Commands 'quotient_type' and
   550 'quotient_definition' may be used for defining types and constants by
   551 quotient constructions.  An example is the type of integers created by
   552 quotienting pairs of natural numbers:
   553 
   554   fun
   555     intrel :: "(nat * nat) => (nat * nat) => bool"
   556   where
   557     "intrel (x, y) (u, v) = (x + v = u + y)"
   558 
   559   quotient_type int = "nat * nat" / intrel
   560     by (auto simp add: equivp_def expand_fun_eq)
   561 
   562   quotient_definition
   563     "0::int" is "(0::nat, 0::nat)"
   564 
   565 The method "lifting" can be used to lift of theorems from the
   566 underlying "raw" type to the quotient type.  The example
   567 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   568 construction and provides a reasoning infrastructure for finite sets.
   569 
   570 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   571 clash with new theory Quotient in Main HOL.
   572 
   573 * Moved the SMT binding into the main HOL session, eliminating
   574 separate HOL-SMT session.
   575 
   576 * List membership infix mem operation is only an input abbreviation.
   577 INCOMPATIBILITY.
   578 
   579 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   580 for future developements; former Library/Word.thy is still present in
   581 the AFP entry RSAPPS.
   582 
   583 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   584 longer shadowed.  INCOMPATIBILITY.
   585 
   586 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   587 INCOMPATIBILITY.
   588 
   589 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   590 INCOMPATIBILITY.
   591 
   592 * Dropped normalizing_semiring etc; use the facts in semiring classes
   593 instead.  INCOMPATIBILITY.
   594 
   595 * Dropped several real-specific versions of lemmas about floor and
   596 ceiling; use the generic lemmas from theory "Archimedean_Field"
   597 instead.  INCOMPATIBILITY.
   598 
   599   floor_number_of_eq         ~> floor_number_of
   600   le_floor_eq_number_of      ~> number_of_le_floor
   601   le_floor_eq_zero           ~> zero_le_floor
   602   le_floor_eq_one            ~> one_le_floor
   603   floor_less_eq_number_of    ~> floor_less_number_of
   604   floor_less_eq_zero         ~> floor_less_zero
   605   floor_less_eq_one          ~> floor_less_one
   606   less_floor_eq_number_of    ~> number_of_less_floor
   607   less_floor_eq_zero         ~> zero_less_floor
   608   less_floor_eq_one          ~> one_less_floor
   609   floor_le_eq_number_of      ~> floor_le_number_of
   610   floor_le_eq_zero           ~> floor_le_zero
   611   floor_le_eq_one            ~> floor_le_one
   612   floor_subtract_number_of   ~> floor_diff_number_of
   613   floor_subtract_one         ~> floor_diff_one
   614   ceiling_number_of_eq       ~> ceiling_number_of
   615   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   616   ceiling_le_zero_eq         ~> ceiling_le_zero
   617   ceiling_le_eq_one          ~> ceiling_le_one
   618   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   619   less_ceiling_eq_zero       ~> zero_less_ceiling
   620   less_ceiling_eq_one        ~> one_less_ceiling
   621   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   622   ceiling_less_eq_zero       ~> ceiling_less_zero
   623   ceiling_less_eq_one        ~> ceiling_less_one
   624   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   625   le_ceiling_eq_zero         ~> zero_le_ceiling
   626   le_ceiling_eq_one          ~> one_le_ceiling
   627   ceiling_subtract_number_of ~> ceiling_diff_number_of
   628   ceiling_subtract_one       ~> ceiling_diff_one
   629 
   630 * Theory "Finite_Set": various folding_XXX locales facilitate the
   631 application of the various fold combinators on finite sets.
   632 
   633 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   634 provides abstract red-black tree type which is backed by "RBT_Impl" as
   635 implementation.  INCOMPATIBILTY.
   636 
   637 * Theory Library/Coinductive_List has been removed -- superseded by
   638 AFP/thys/Coinductive.
   639 
   640 * Theory PReal, including the type "preal" and related operations, has
   641 been removed.  INCOMPATIBILITY.
   642 
   643 * Real: new development using Cauchy Sequences.
   644 
   645 * Split off theory "Big_Operators" containing setsum, setprod,
   646 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   647 
   648 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   649 "Int" etc.  INCOMPATIBILITY.
   650 
   651 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   652 
   653 * New set of rules "ac_simps" provides combined assoc / commute
   654 rewrites for all interpretations of the appropriate generic locales.
   655 
   656 * Renamed theory "OrderedGroup" to "Groups" and split theory
   657 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   658 appropriate and more consistent names suitable for name prefixes
   659 within the HOL theories.  INCOMPATIBILITY.
   660 
   661 * Some generic constants have been put to appropriate theories:
   662   - less_eq, less: Orderings
   663   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   664   - inverse, divide: Rings
   665 INCOMPATIBILITY.
   666 
   667 * More consistent naming of type classes involving orderings (and
   668 lattices):
   669 
   670     lower_semilattice                   ~> semilattice_inf
   671     upper_semilattice                   ~> semilattice_sup
   672 
   673     dense_linear_order                  ~> dense_linorder
   674 
   675     pordered_ab_group_add               ~> ordered_ab_group_add
   676     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   677     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   678     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   679     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   680     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   681     pordered_cancel_semiring            ~> ordered_cancel_semiring
   682     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   683     pordered_comm_ring                  ~> ordered_comm_ring
   684     pordered_comm_semiring              ~> ordered_comm_semiring
   685     pordered_ring                       ~> ordered_ring
   686     pordered_ring_abs                   ~> ordered_ring_abs
   687     pordered_semiring                   ~> ordered_semiring
   688 
   689     ordered_ab_group_add                ~> linordered_ab_group_add
   690     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   691     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   692     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   693     ordered_field                       ~> linordered_field
   694     ordered_field_no_lb                 ~> linordered_field_no_lb
   695     ordered_field_no_ub                 ~> linordered_field_no_ub
   696     ordered_field_dense_linear_order    ~> dense_linordered_field
   697     ordered_idom                        ~> linordered_idom
   698     ordered_ring                        ~> linordered_ring
   699     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   700     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   701     ordered_ring_strict                 ~> linordered_ring_strict
   702     ordered_semidom                     ~> linordered_semidom
   703     ordered_semiring                    ~> linordered_semiring
   704     ordered_semiring_1                  ~> linordered_semiring_1
   705     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   706     ordered_semiring_strict             ~> linordered_semiring_strict
   707 
   708   The following slightly odd type classes have been moved to a
   709   separate theory Library/Lattice_Algebras:
   710 
   711     lordered_ab_group_add               ~> lattice_ab_group_add
   712     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   713     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   714     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   715     lordered_ring                       ~> lattice_ring
   716 
   717 INCOMPATIBILITY.
   718 
   719 * Refined field classes:
   720   - classes division_ring_inverse_zero, field_inverse_zero,
   721     linordered_field_inverse_zero include rule inverse 0 = 0 --
   722     subsumes former division_by_zero class;
   723   - numerous lemmas have been ported from field to division_ring.
   724 INCOMPATIBILITY.
   725 
   726 * Refined algebra theorem collections:
   727   - dropped theorem group group_simps, use algebra_simps instead;
   728   - dropped theorem group ring_simps, use field_simps instead;
   729   - proper theorem collection field_simps subsumes former theorem
   730     groups field_eq_simps and field_simps;
   731   - dropped lemma eq_minus_self_iff which is a duplicate for
   732     equal_neg_zero.
   733 INCOMPATIBILITY.
   734 
   735 * Theory Finite_Set and List: some lemmas have been generalized from
   736 sets to lattices:
   737 
   738   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   739   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   740   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   741   union_Union_fold_union        ~> sup_Sup_fold_sup
   742   Inter_fold_inter              ~> Inf_fold_inf
   743   Union_fold_union              ~> Sup_fold_sup
   744   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   745   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   746   INTER_fold_inter              ~> INFI_fold_inf
   747   UNION_fold_union              ~> SUPR_fold_sup
   748 
   749 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   750 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   751 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   752 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   753 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   754 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   755 
   756 * Reorganized theory Multiset: swapped notation of pointwise and
   757 multiset order:
   758 
   759   - pointwise ordering is instance of class order with standard syntax
   760     <= and <;
   761   - multiset ordering has syntax <=# and <#; partial order properties
   762     are provided by means of interpretation with prefix
   763     multiset_order;
   764   - less duplication, less historical organization of sections,
   765     conversion from associations lists to multisets, rudimentary code
   766     generation;
   767   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   768     if needed.
   769 
   770 Renamed:
   771 
   772   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   773   multi_count_ext  ~>  multiset_ext
   774   diff_union_inverse2  ~>  diff_union_cancelR
   775 
   776 INCOMPATIBILITY.
   777 
   778 * Theory Permutation: replaced local "remove" by List.remove1.
   779 
   780 * Code generation: ML and OCaml code is decorated with signatures.
   781 
   782 * Theory List: added transpose.
   783 
   784 * Library/Nat_Bijection.thy is a collection of bijective functions
   785 between nat and other types, which supersedes the older libraries
   786 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   787 
   788   Constants:
   789   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   790   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   791   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   792   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   793   Countable.pair_encode           ~> prod_encode
   794   NatIso.prod2nat                 ~> prod_encode
   795   NatIso.nat2prod                 ~> prod_decode
   796   NatIso.sum2nat                  ~> sum_encode
   797   NatIso.nat2sum                  ~> sum_decode
   798   NatIso.list2nat                 ~> list_encode
   799   NatIso.nat2list                 ~> list_decode
   800   NatIso.set2nat                  ~> set_encode
   801   NatIso.nat2set                  ~> set_decode
   802 
   803   Lemmas:
   804   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   805   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   806   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   807   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   808   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   809   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   810   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   811   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   812   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   813   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   814   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   815   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   816   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   817 
   818 * Sledgehammer:
   819   - Renamed ATP commands:
   820     atp_info     ~> sledgehammer running_atps
   821     atp_kill     ~> sledgehammer kill_atps
   822     atp_messages ~> sledgehammer messages
   823     atp_minimize ~> sledgehammer minimize
   824     print_atps   ~> sledgehammer available_atps
   825     INCOMPATIBILITY.
   826   - Added user's manual ("isabelle doc sledgehammer").
   827   - Added option syntax and "sledgehammer_params" to customize
   828     Sledgehammer's behavior.  See the manual for details.
   829   - Modified the Isar proof reconstruction code so that it produces
   830     direct proofs rather than proofs by contradiction.  (This feature
   831     is still experimental.)
   832   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   833     full-typed mode.
   834   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   835 
   836 * Nitpick:
   837   - Added and implemented "binary_ints" and "bits" options.
   838   - Added "std" option and implemented support for nonstandard models.
   839   - Added and implemented "finitize" option to improve the precision
   840     of infinite datatypes based on a monotonicity analysis.
   841   - Added support for quotient types.
   842   - Added support for "specification" and "ax_specification"
   843     constructs.
   844   - Added support for local definitions (for "function" and
   845     "termination" proofs).
   846   - Added support for term postprocessors.
   847   - Optimized "Multiset.multiset" and "FinFun.finfun".
   848   - Improved efficiency of "destroy_constrs" optimization.
   849   - Fixed soundness bugs related to "destroy_constrs" optimization and
   850     record getters.
   851   - Fixed soundness bug related to higher-order constructors.
   852   - Fixed soundness bug when "full_descrs" is enabled.
   853   - Improved precision of set constructs.
   854   - Added "atoms" option.
   855   - Added cache to speed up repeated Kodkod invocations on the same
   856     problems.
   857   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   858     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   859     "SAT4J_Light".  INCOMPATIBILITY.
   860   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   861     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   862   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   863 
   864 * Method "induct" now takes instantiations of the form t, where t is not
   865   a variable, as a shorthand for "x == t", where x is a fresh variable.
   866   If this is not intended, t has to be enclosed in parentheses.
   867   By default, the equalities generated by definitional instantiations
   868   are pre-simplified, which may cause parameters of inductive cases
   869   to disappear, or may even delete some of the inductive cases.
   870   Use "induct (no_simp)" instead of "induct" to restore the old
   871   behaviour. The (no_simp) option is also understood by the "cases"
   872   and "nominal_induct" methods, which now perform pre-simplification, too.
   873   INCOMPATIBILITY.
   874 
   875 
   876 *** HOLCF ***
   877 
   878 * Variable names in lemmas generated by the domain package have
   879 changed; the naming scheme is now consistent with the HOL datatype
   880 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   881 
   882 * The domain package no longer defines the function "foo_copy" for
   883 recursive domain "foo".  The reach lemma is now stated directly in
   884 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   885 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   886 
   887 * Most definedness lemmas generated by the domain package (previously
   888 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   889 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   890 Proofs that used definedness lemmas as intro rules may break,
   891 potential INCOMPATIBILITY.
   892 
   893 * Induction and casedist rules generated by the domain package now
   894 declare proper case_names (one called "bottom", and one named for each
   895 constructor).  INCOMPATIBILITY.
   896 
   897 * For mutually-recursive domains, separate "reach" and "take_lemma"
   898 rules are generated for each domain, INCOMPATIBILITY.
   899 
   900   foo_bar.reach       ~> foo.reach  bar.reach
   901   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   902 
   903 * Some lemmas generated by the domain package have been renamed for
   904 consistency with the datatype package, INCOMPATIBILITY.
   905 
   906   foo.ind        ~> foo.induct
   907   foo.finite_ind ~> foo.finite_induct
   908   foo.coind      ~> foo.coinduct
   909   foo.casedist   ~> foo.exhaust
   910   foo.exhaust    ~> foo.nchotomy
   911 
   912 * For consistency with other definition packages, the fixrec package
   913 now generates qualified theorem names, INCOMPATIBILITY.
   914 
   915   foo_simps  ~> foo.simps
   916   foo_unfold ~> foo.unfold
   917   foo_induct ~> foo.induct
   918 
   919 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   920 method and internal fixrec proofs now use the default simpset instead.
   921 INCOMPATIBILITY.
   922 
   923 * The "contlub" predicate has been removed.  Proof scripts should use
   924 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   925 
   926 * The "admw" predicate has been removed, INCOMPATIBILITY.
   927 
   928 * The constants cpair, cfst, and csnd have been removed in favor of
   929 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   930 
   931 
   932 *** ML ***
   933 
   934 * Antiquotations for basic formal entities:
   935 
   936     @{class NAME}         -- type class
   937     @{class_syntax NAME}  -- syntax representation of the above
   938 
   939     @{type_name NAME}     -- logical type
   940     @{type_abbrev NAME}   -- type abbreviation
   941     @{nonterminal NAME}   -- type of concrete syntactic category
   942     @{type_syntax NAME}   -- syntax representation of any of the above
   943 
   944     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   945     @{const_abbrev NAME}  -- abbreviated constant
   946     @{const_syntax NAME}  -- syntax representation of any of the above
   947 
   948 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   949 syntax constant (cf. 'syntax' command).
   950 
   951 * Antiquotation @{make_string} inlines a function to print arbitrary
   952 values similar to the ML toplevel.  The result is compiler dependent
   953 and may fall back on "?" in certain situations.
   954 
   955 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   956 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   957 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   958 not work with the asynchronous Isar document model.
   959 
   960 * Configuration options now admit dynamic default values, depending on
   961 the context or even global references.
   962 
   963 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   964 uses an efficient external library if available (for Poly/ML).
   965 
   966 * Renamed some important ML structures, while keeping the old names
   967 for some time as aliases within the structure Legacy:
   968 
   969   OuterKeyword  ~>  Keyword
   970   OuterLex      ~>  Token
   971   OuterParse    ~>  Parse
   972   OuterSyntax   ~>  Outer_Syntax
   973   PrintMode     ~>  Print_Mode
   974   SpecParse     ~>  Parse_Spec
   975   ThyInfo       ~>  Thy_Info
   976   ThyLoad       ~>  Thy_Load
   977   ThyOutput     ~>  Thy_Output
   978   TypeInfer     ~>  Type_Infer
   979 
   980 Note that "open Legacy" simplifies porting of sources, but forgetting
   981 to remove it again will complicate porting again in the future.
   982 
   983 * Most operations that refer to a global context are named
   984 accordingly, e.g. Simplifier.global_context or
   985 ProofContext.init_global.  There are some situations where a global
   986 context actually works, but under normal circumstances one needs to
   987 pass the proper local context through the code!
   988 
   989 * Discontinued old TheoryDataFun with its copy/init operation -- data
   990 needs to be pure.  Functor Theory_Data_PP retains the traditional
   991 Pretty.pp argument to merge, which is absent in the standard
   992 Theory_Data version.
   993 
   994 * Sorts.certify_sort and derived "cert" operations for types and terms
   995 no longer minimize sorts.  Thus certification at the boundary of the
   996 inference kernel becomes invariant under addition of class relations,
   997 which is an important monotonicity principle.  Sorts are now minimized
   998 in the syntax layer only, at the boundary between the end-user and the
   999 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1000 explicitly in rare situations.
  1001 
  1002 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1003 emphasize that this is in no way a standard operation.
  1004 INCOMPATIBILITY.
  1005 
  1006 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1007 usual for resolution.  Rare INCOMPATIBILITY.
  1008 
  1009 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1010 to emphasize that these only work in a global situation (which is
  1011 quite rare).
  1012 
  1013 * Curried take and drop in library.ML; negative length is interpreted
  1014 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1015 
  1016 * Proof terms: type substitutions on proof constants now use canonical
  1017 order of type variables.  INCOMPATIBILITY for tools working with proof
  1018 terms.
  1019 
  1020 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1021 may no longer carry premises.  User-level specifications are
  1022 transformed accordingly by Thm.add_axiom/add_def.
  1023 
  1024 
  1025 *** System ***
  1026 
  1027 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1028 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1029 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1030 
  1031 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1032 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1033 respectively.
  1034 
  1035 * Old lib/scripts/polyml-platform is superseded by the
  1036 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1037 variant, even on a 64 bit machine.  The following example setting
  1038 prefers 64 bit if available:
  1039 
  1040   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1041 
  1042 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1043 Isabelle/Scala layer for advanced prover interaction and integration.
  1044 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1045 component.
  1046 
  1047 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1048 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1049 similar to the default assignment of the document preparation system
  1050 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1051 provides some operations for direct access to the font without asking
  1052 the user for manual installation.
  1053 
  1054 
  1055 
  1056 New in Isabelle2009-1 (December 2009)
  1057 -------------------------------------
  1058 
  1059 *** General ***
  1060 
  1061 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1062 one backslash should be used, even in ML sources.
  1063 
  1064 
  1065 *** Pure ***
  1066 
  1067 * Locale interpretation propagates mixins along the locale hierarchy.
  1068 The currently only available mixins are the equations used to map
  1069 local definitions to terms of the target domain of an interpretation.
  1070 
  1071 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1072 loc" to print all interpretations of locale "loc" in the theory.
  1073 Interpretations in proofs are not shown.
  1074 
  1075 * Thoroughly revised locales tutorial.  New section on conditional
  1076 interpretation.
  1077 
  1078 * On instantiation of classes, remaining undefined class parameters
  1079 are formally declared.  INCOMPATIBILITY.
  1080 
  1081 
  1082 *** Document preparation ***
  1083 
  1084 * New generalized style concept for printing terms: @{foo (style) ...}
  1085 instead of @{foo_style style ...}  (old form is still retained for
  1086 backward compatibility).  Styles can be also applied for
  1087 antiquotations prop, term_type and typeof.
  1088 
  1089 
  1090 *** HOL ***
  1091 
  1092 * New proof method "smt" for a combination of first-order logic with
  1093 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1094 fixed-size bitvectors; there is also basic support for higher-order
  1095 features (esp. lambda abstractions).  It is an incomplete decision
  1096 procedure based on external SMT solvers using the oracle mechanism;
  1097 for the SMT solver Z3, this method is proof-producing.  Certificates
  1098 are provided to avoid calling the external solvers solely for
  1099 re-checking proofs.  Due to a remote SMT service there is no need for
  1100 installing SMT solvers locally.  See src/HOL/SMT.
  1101 
  1102 * New commands to load and prove verification conditions generated by
  1103 the Boogie program verifier or derived systems (e.g. the Verifying C
  1104 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1105 
  1106 * New counterexample generator tool 'nitpick' based on the Kodkod
  1107 relational model finder.  See src/HOL/Tools/Nitpick and
  1108 src/HOL/Nitpick_Examples.
  1109 
  1110 * New commands 'code_pred' and 'values' to invoke the predicate
  1111 compiler and to enumerate values of inductive predicates.
  1112 
  1113 * A tabled implementation of the reflexive transitive closure.
  1114 
  1115 * New implementation of quickcheck uses generic code generator;
  1116 default generators are provided for all suitable HOL types, records
  1117 and datatypes.  Old quickcheck can be re-activated importing theory
  1118 Library/SML_Quickcheck.
  1119 
  1120 * New testing tool Mirabelle for automated proof tools.  Applies
  1121 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1122 every proof step in a theory.  To be used in batch mode via the
  1123 "mirabelle" utility.
  1124 
  1125 * New proof method "sos" (sum of squares) for nonlinear real
  1126 arithmetic (originally due to John Harison). It requires theory
  1127 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1128 works well in practice on quantifier-free real arithmetic with +, -,
  1129 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1130 inequalities between polynomials.  It makes use of external
  1131 semidefinite programming solvers.  Method "sos" generates a
  1132 certificate that can be pasted into the proof thus avoiding the need
  1133 to call an external tool every time the proof is checked.  See
  1134 src/HOL/Library/Sum_Of_Squares.
  1135 
  1136 * New method "linarith" invokes existing linear arithmetic decision
  1137 procedure only.
  1138 
  1139 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1140 
  1141 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1142 Causes full type information to be output to the ATPs.  This slows
  1143 ATPs down considerably but eliminates a source of unsound "proofs"
  1144 that fail later.
  1145 
  1146 * New method "metisFT": A version of metis that uses full type
  1147 information in order to avoid failures of proof reconstruction.
  1148 
  1149 * New evaluator "approximate" approximates an real valued term using
  1150 the same method as the approximation method.
  1151 
  1152 * Method "approximate" now supports arithmetic expressions as
  1153 boundaries of intervals and implements interval splitting and Taylor
  1154 series expansion.
  1155 
  1156 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1157 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1158 
  1159 * New theory SupInf of the supremum and infimum operators for sets of
  1160 reals.
  1161 
  1162 * New theory Probability, which contains a development of measure
  1163 theory, eventually leading to Lebesgue integration and probability.
  1164 
  1165 * Extended Multivariate Analysis to include derivation and Brouwer's
  1166 fixpoint theorem.
  1167 
  1168 * Reorganization of number theory, INCOMPATIBILITY:
  1169   - new number theory development for nat and int, in theories Divides
  1170     and GCD as well as in new session Number_Theory
  1171   - some constants and facts now suffixed with _nat and _int
  1172     accordingly
  1173   - former session NumberTheory now named Old_Number_Theory, including
  1174     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1175   - moved theory Pocklington from src/HOL/Library to
  1176     src/HOL/Old_Number_Theory
  1177 
  1178 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1179 lcm of finite and infinite sets. It is shown that they form a complete
  1180 lattice.
  1181 
  1182 * Class semiring_div requires superclass no_zero_divisors and proof of
  1183 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1184 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1185 generalized to class semiring_div, subsuming former theorems
  1186 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1187 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1188 INCOMPATIBILITY.
  1189 
  1190 * Refinements to lattice classes and sets:
  1191   - less default intro/elim rules in locale variant, more default
  1192     intro/elim rules in class variant: more uniformity
  1193   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1194     le_inf_iff
  1195   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1196     sup_aci)
  1197   - renamed ACI to inf_sup_aci
  1198   - new class "boolean_algebra"
  1199   - class "complete_lattice" moved to separate theory
  1200     "Complete_Lattice"; corresponding constants (and abbreviations)
  1201     renamed and with authentic syntax:
  1202     Set.Inf ~>    Complete_Lattice.Inf
  1203     Set.Sup ~>    Complete_Lattice.Sup
  1204     Set.INFI ~>   Complete_Lattice.INFI
  1205     Set.SUPR ~>   Complete_Lattice.SUPR
  1206     Set.Inter ~>  Complete_Lattice.Inter
  1207     Set.Union ~>  Complete_Lattice.Union
  1208     Set.INTER ~>  Complete_Lattice.INTER
  1209     Set.UNION ~>  Complete_Lattice.UNION
  1210   - authentic syntax for
  1211     Set.Pow
  1212     Set.image
  1213   - mere abbreviations:
  1214     Set.empty               (for bot)
  1215     Set.UNIV                (for top)
  1216     Set.inter               (for inf, formerly Set.Int)
  1217     Set.union               (for sup, formerly Set.Un)
  1218     Complete_Lattice.Inter  (for Inf)
  1219     Complete_Lattice.Union  (for Sup)
  1220     Complete_Lattice.INTER  (for INFI)
  1221     Complete_Lattice.UNION  (for SUPR)
  1222   - object-logic definitions as far as appropriate
  1223 
  1224 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1225 Un_subset_iff are explicitly deleted as default simp rules; then also
  1226 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1227 deleted to achieve the desired effect.
  1228 
  1229 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1230 rules by default any longer; the same applies to min_max.inf_absorb1
  1231 etc.  INCOMPATIBILITY.
  1232 
  1233 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1234 pred_set_conv by default.  INCOMPATIBILITY.
  1235 
  1236 * Power operations on relations and functions are now one dedicated
  1237 constant "compow" with infix syntax "^^".  Power operation on
  1238 multiplicative monoids retains syntax "^" and is now defined generic
  1239 in class power.  INCOMPATIBILITY.
  1240 
  1241 * Relation composition "R O S" now has a more standard argument order:
  1242 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1243 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1244 break, since the O_assoc rule was not rewritten like this.  Fix using
  1245 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1246 
  1247 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1248 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1249 INCOMPATIBILITY.
  1250 
  1251 * Most rules produced by inductive and datatype package have mandatory
  1252 prefixes.  INCOMPATIBILITY.
  1253 
  1254 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1255 the attribute of the same name.  Each of the theorems in the list
  1256 DERIV_intros assumes composition with an additional function and
  1257 matches a variable to the derivative, which has to be solved by the
  1258 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1259 of most elementary terms.  Former Maclauren.DERIV_tac and
  1260 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1261 INCOMPATIBILITY.
  1262 
  1263 * Code generator attributes follow the usual underscore convention:
  1264     code_unfold     replaces    code unfold
  1265     code_post       replaces    code post
  1266     etc.
  1267   INCOMPATIBILITY.
  1268 
  1269 * Renamed methods:
  1270     sizechange -> size_change
  1271     induct_scheme -> induction_schema
  1272   INCOMPATIBILITY.
  1273 
  1274 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1275 INCOMPATIBILITY, use "undefined" directly.
  1276 
  1277 * Renamed theorems:
  1278     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1279     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1280     Suc_plus1 -> Suc_eq_plus1
  1281     *anti_sym -> *antisym*
  1282     vector_less_eq_def -> vector_le_def
  1283   INCOMPATIBILITY.
  1284 
  1285 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1286 INCOMPATIBILITY.
  1287 
  1288 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1289 INCOMPATIBILITY.
  1290 
  1291 
  1292 *** HOLCF ***
  1293 
  1294 * Theory Representable defines a class "rep" of domains that are
  1295 representable (via an ep-pair) in the universal domain type "udom".
  1296 Instances are provided for all type constructors defined in HOLCF.
  1297 
  1298 * The 'new_domain' command is a purely definitional version of the
  1299 domain package, for representable domains.  Syntax is identical to the
  1300 old domain package.  The 'new_domain' package also supports indirect
  1301 recursion using previously-defined type constructors.  See
  1302 src/HOLCF/ex/New_Domain.thy for examples.
  1303 
  1304 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1305 on the left-hand side of an equation, and then performs
  1306 simplification.  Rewriting is done using rules declared with the
  1307 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1308 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1309 
  1310 * The pattern-match compiler in 'fixrec' can now handle constructors
  1311 with HOL function types.  Pattern-match combinators for the Pair
  1312 constructor are pre-configured.
  1313 
  1314 * The 'fixrec' package now produces better fixed-point induction rules
  1315 for mutually-recursive definitions:  Induction rules have conclusions
  1316 of the form "P foo bar" instead of "P <foo, bar>".
  1317 
  1318 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1319 been renamed to "below".  The name "below" now replaces "less" in many
  1320 theorem names.  (Legacy theorem names using "less" are still supported
  1321 as well.)
  1322 
  1323 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1324 patterns can be used to generate strictness rules, or to make
  1325 functions more strict (much like the bang-patterns supported by the
  1326 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1327 examples.
  1328 
  1329 
  1330 *** ML ***
  1331 
  1332 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1333 errors and run-time exceptions, including detailed source positions.
  1334 
  1335 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1336 identified entries, with some additional information such as source
  1337 position, logical grouping etc.
  1338 
  1339 * Theory and context data is now introduced by the simplified and
  1340 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1341 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1342 copy operation) is still available for some time.
  1343 
  1344 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1345 provides a high-level programming interface to synchronized state
  1346 variables with atomic update.  This works via pure function
  1347 application within a critical section -- its runtime should be as
  1348 short as possible; beware of deadlocks if critical code is nested,
  1349 either directly or indirectly via other synchronized variables!
  1350 
  1351 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1352 wraps raw ML references, explicitly indicating their non-thread-safe
  1353 behaviour.  The Isar toplevel keeps this structure open, to
  1354 accommodate Proof General as well as quick and dirty interactive
  1355 experiments with references.
  1356 
  1357 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1358 parallel tactical reasoning.
  1359 
  1360 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1361 are similar to SUBPROOF, but are slightly more flexible: only the
  1362 specified parts of the subgoal are imported into the context, and the
  1363 body tactic may introduce new subgoals and schematic variables.
  1364 
  1365 * Old tactical METAHYPS, which does not observe the proof context, has
  1366 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1367 or Subgoal.FOCUS etc.
  1368 
  1369 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1370 functors have their own ML name space there is no point to mark them
  1371 separately.)  Minor INCOMPATIBILITY.
  1372 
  1373 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1374 
  1375 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1376 INCOMPATIBILITY.
  1377 
  1378 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1379 mode, which avoids critical setmp.
  1380 
  1381 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1382 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1383 Attrib/Method.setup introduced in Isabelle2009.
  1384 
  1385 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1386 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1387 last resort.  INCOMPATIBILITY.
  1388 
  1389 * Display.pretty_thm now requires a proper context (cf. former
  1390 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1391 or even Display.pretty_thm_without_context as last resort.
  1392 INCOMPATIBILITY.
  1393 
  1394 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1395 Syntax.pretty_typ/term directly, preferably with proper context
  1396 instead of global theory.
  1397 
  1398 
  1399 *** System ***
  1400 
  1401 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1402 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1403 usedir option -q.
  1404 
  1405 * Support for additional "Isabelle components" via etc/components, see
  1406 also the system manual.
  1407 
  1408 * The isabelle makeall tool now operates on all components with
  1409 IsaMakefile, not just hardwired "logics".
  1410 
  1411 * Removed "compress" option from isabelle-process and isabelle usedir;
  1412 this is always enabled.
  1413 
  1414 * Discontinued support for Poly/ML 4.x versions.
  1415 
  1416 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1417 on a given logic image.  This requires the lighttpd webserver and is
  1418 currently supported on Linux only.
  1419 
  1420 
  1421 
  1422 New in Isabelle2009 (April 2009)
  1423 --------------------------------
  1424 
  1425 *** General ***
  1426 
  1427 * Simplified main Isabelle executables, with less surprises on
  1428 case-insensitive file-systems (such as Mac OS).
  1429 
  1430   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1431     "isatool."
  1432 
  1433   - The former "isabelle" alias for "isabelle-process" has been
  1434     removed (should rarely occur to regular users).
  1435 
  1436   - The former "isabelle-interface" and its alias "Isabelle" have been
  1437     removed (interfaces are now regular Isabelle tools).
  1438 
  1439 Within scripts and make files, the Isabelle environment variables
  1440 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1441 respectively.  (The latter are still available as legacy feature.)
  1442 
  1443 The old isabelle-interface wrapper could react in confusing ways if
  1444 the interface was uninstalled or changed otherwise.  Individual
  1445 interface tool configuration is now more explicit, see also the
  1446 Isabelle system manual.  In particular, Proof General is now available
  1447 via "isabelle emacs".
  1448 
  1449 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1450 purge installed copies of Isabelle executables and re-run "isabelle
  1451 install -p ...", or use symlinks.
  1452 
  1453 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1454 old ~/isabelle, which was slightly non-standard and apt to cause
  1455 surprises on case-insensitive file-systems (such as Mac OS).
  1456 
  1457 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1458 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1459 care is required when using older releases of Isabelle.  Note that
  1460 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1461 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1462 
  1463 * Proofs of fully specified statements are run in parallel on
  1464 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1465 a regular 4-core machine, if the initial heap space is made reasonably
  1466 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1467 
  1468 * The main reference manuals ("isar-ref", "implementation", and
  1469 "system") have been updated and extended.  Formally checked references
  1470 as hyperlinks are now available uniformly.
  1471 
  1472 
  1473 *** Pure ***
  1474 
  1475 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1476 respects.  The most important changes are listed below.  See the
  1477 Tutorial on Locales ("locales" manual) for details.
  1478 
  1479 - In locale expressions, instantiation replaces renaming.  Parameters
  1480 must be declared in a for clause.  To aid compatibility with previous
  1481 parameter inheritance, in locale declarations, parameters that are not
  1482 'touched' (instantiation position "_" or omitted) are implicitly added
  1483 with their syntax at the beginning of the for clause.
  1484 
  1485 - Syntax from abbreviations and definitions in locales is available in
  1486 locale expressions and context elements.  The latter is particularly
  1487 useful in locale declarations.
  1488 
  1489 - More flexible mechanisms to qualify names generated by locale
  1490 expressions.  Qualifiers (prefixes) may be specified in locale
  1491 expressions, and can be marked as mandatory (syntax: "name!:") or
  1492 optional (syntax "name?:").  The default depends for plain "name:"
  1493 depends on the situation where a locale expression is used: in
  1494 commands 'locale' and 'sublocale' prefixes are optional, in
  1495 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1496 implicit qualifiers derived from the parameter names of a locale are
  1497 no longer generated.
  1498 
  1499 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1500 instantiation clause in "interpretation" and "interpret" (square
  1501 brackets) is no longer available.  Use locale expressions.
  1502 
  1503 - When converting proof scripts, mandatory qualifiers in
  1504 'interpretation' and 'interpret' should be retained by default, even
  1505 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1506 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1507 in locale expressions range over a single locale instance only.
  1508 
  1509 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1510 In existing theorem specifications replace the includes element by the
  1511 respective context elements of the included locale, omitting those
  1512 that are already present in the theorem specification.  Multiple
  1513 assume elements of a locale should be replaced by a single one
  1514 involving the locale predicate.  In the proof body, declarations (most
  1515 notably theorems) may be regained by interpreting the respective
  1516 locales in the proof context as required (command "interpret").
  1517 
  1518 If using "includes" in replacement of a target solely because the
  1519 parameter types in the theorem are not as general as in the target,
  1520 consider declaring a new locale with additional type constraints on
  1521 the parameters (context element "constrains").
  1522 
  1523 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1524 
  1525 - Locale interpretation commands no longer attempt to simplify goal.
  1526 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1527 methods intro_locales and unfold_locales to clarify.
  1528 
  1529 - Locale interpretation commands no longer accept interpretation
  1530 attributes.  INCOMPATIBILITY.
  1531 
  1532 * Class declaration: so-called "base sort" must not be given in import
  1533 list any longer, but is inferred from the specification.  Particularly
  1534 in HOL, write
  1535 
  1536     class foo = ...
  1537 
  1538 instead of
  1539 
  1540     class foo = type + ...
  1541 
  1542 * Class target: global versions of theorems stemming do not carry a
  1543 parameter prefix any longer.  INCOMPATIBILITY.
  1544 
  1545 * Class 'instance' command no longer accepts attached definitions.
  1546 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1547 
  1548 * Recovered hiding of consts, which was accidentally broken in
  1549 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1550 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1551 
  1552 * Slightly more coherent Pure syntax, with updated documentation in
  1553 isar-ref manual.  Removed locales meta_term_syntax and
  1554 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1555 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1556 directly in regular applications.
  1557 
  1558 * There is a new syntactic category "float_const" for signed decimal
  1559 fractions (e.g. 123.45 or -123.45).
  1560 
  1561 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1562 interface with 'setup' command instead.
  1563 
  1564 * Command 'local_setup' is similar to 'setup', but operates on a local
  1565 theory context.
  1566 
  1567 * The 'axiomatization' command now only works within a global theory
  1568 context.  INCOMPATIBILITY.
  1569 
  1570 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1571 hypotheses.  Sorts required in the course of reasoning need to be
  1572 covered by the constraints in the initial statement, completed by the
  1573 type instance information of the background theory.  Non-trivial sort
  1574 hypotheses, which rarely occur in practice, may be specified via
  1575 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1576 
  1577   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1578 
  1579 The result contains an implicit sort hypotheses as before --
  1580 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1581 normalization.
  1582 
  1583 * Generalized Isar history, with support for linear undo, direct state
  1584 addressing etc.
  1585 
  1586 * Changed defaults for unify configuration options:
  1587 
  1588   unify_trace_bound = 50 (formerly 25)
  1589   unify_search_bound = 60 (formerly 30)
  1590 
  1591 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1592 
  1593   a) On theory merge, the last set of code equations for a particular
  1594      constant is taken (in accordance with the policy applied by other
  1595      parts of the code generator framework).
  1596 
  1597   b) Code equations stemming from explicit declarations (e.g. code
  1598      attribute) gain priority over default code equations stemming
  1599      from definition, primrec, fun etc.
  1600 
  1601 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1602 
  1603 * Unified theorem tables for both code generators.  Thus [code
  1604 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1605 
  1606 * Command 'find_consts' searches for constants based on type and name
  1607 patterns, e.g.
  1608 
  1609     find_consts "_ => bool"
  1610 
  1611 By default, matching is against subtypes, but it may be restricted to
  1612 the whole type.  Searching by name is possible.  Multiple queries are
  1613 conjunctive and queries may be negated by prefixing them with a
  1614 hyphen:
  1615 
  1616     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1617 
  1618 * New 'find_theorems' criterion "solves" matches theorems that
  1619 directly solve the current goal (modulo higher-order unification).
  1620 
  1621 * Auto solve feature for main theorem statements: whenever a new goal
  1622 is stated, "find_theorems solves" is called; any theorems that could
  1623 solve the lemma directly are listed as part of the goal state.
  1624 Cf. associated options in Proof General Isabelle settings menu,
  1625 enabled by default, with reasonable timeout for pathological cases of
  1626 higher-order unification.
  1627 
  1628 
  1629 *** Document preparation ***
  1630 
  1631 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1632 demanding keyword 'by' and supporting the full method expression
  1633 syntax just like the Isar command 'by'.
  1634 
  1635 
  1636 *** HOL ***
  1637 
  1638 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1639 points Main and Complex_Main remain as before.
  1640 
  1641 * Logic image HOL-Plain provides a minimal HOL with the most important
  1642 tools available (inductive, datatype, primrec, ...).  This facilitates
  1643 experimentation and tool development.  Note that user applications
  1644 (and library theories) should never refer to anything below theory
  1645 Main, as before.
  1646 
  1647 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1648 experimentation due to shorter build times.
  1649 
  1650 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1651 were previously part of former HOL-Complex.  Entry point Hyperreal
  1652 remains valid, but theories formerly using Complex_Main should now use
  1653 new entry point Hypercomplex.
  1654 
  1655 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1656 Posix processes.  Avoids potentially expensive forking of the ML
  1657 process.  New thread-based implementation also works on non-Unix
  1658 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1659 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1660 commands are covered in the isar-ref manual.
  1661 
  1662 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1663 sledgehammer without local ATP installation (Vampire etc.). Other
  1664 provers may be included via suitable ML wrappers, see also
  1665 src/HOL/ATP_Linkup.thy.
  1666 
  1667 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1668 menu.
  1669 
  1670 * The metis method no longer fails because the theorem is too trivial
  1671 (contains the empty clause).
  1672 
  1673 * The metis method now fails in the usual manner, rather than raising
  1674 an exception, if it determines that it cannot prove the theorem.
  1675 
  1676 * Method "coherent" implements a prover for coherent logic (see also
  1677 src/Tools/coherent.ML).
  1678 
  1679 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1680 "undefined" is the right choice to replace "arbitrary", though
  1681 logically there is no difference.  INCOMPATIBILITY.
  1682 
  1683 * Command "value" now integrates different evaluation mechanisms.  The
  1684 result of the first successful evaluation mechanism is printed.  In
  1685 square brackets a particular named evaluation mechanisms may be
  1686 specified (currently, [SML], [code] or [nbe]).  See further
  1687 src/HOL/ex/Eval_Examples.thy.
  1688 
  1689 * Normalization by evaluation now allows non-leftlinear equations.
  1690 Declare with attribute [code nbe].
  1691 
  1692 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1693 as the structured Isar versions "cases" and "induct", cf. the
  1694 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1695 are now presented as a list of individual projections
  1696 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1697 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1698 rare situations a different rule is selected --- notably nested tuple
  1699 elimination instead of former prod.exhaust: use explicit (case_tac t
  1700 rule: prod.exhaust) here.
  1701 
  1702 * Attributes "cases", "induct", "coinduct" support "del" option.
  1703 
  1704 * Removed fact "case_split_thm", which duplicates "case_split".
  1705 
  1706 * The option datatype has been moved to a new theory Option.  Renamed
  1707 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1708 
  1709 * New predicate "strict_mono" classifies strict functions on partial
  1710 orders.  With strict functions on linear orders, reasoning about
  1711 (in)equalities is facilitated by theorems "strict_mono_eq",
  1712 "strict_mono_less_eq" and "strict_mono_less".
  1713 
  1714 * Some set operations are now proper qualified constants with
  1715 authentic syntax.  INCOMPATIBILITY:
  1716 
  1717     op Int ~>   Set.Int
  1718     op Un ~>    Set.Un
  1719     INTER ~>    Set.INTER
  1720     UNION ~>    Set.UNION
  1721     Inter ~>    Set.Inter
  1722     Union ~>    Set.Union
  1723     {} ~>       Set.empty
  1724     UNIV ~>     Set.UNIV
  1725 
  1726 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1727 theory Set.
  1728 
  1729 * Auxiliary class "itself" has disappeared -- classes without any
  1730 parameter are treated as expected by the 'class' command.
  1731 
  1732 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1733 
  1734 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1735 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1736 
  1737 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1738 method "approximation".  It proves formulas on real values by using
  1739 interval arithmetic.  In the formulas are also the transcendental
  1740 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1741 allowed. For examples see
  1742 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1743 
  1744 * Theory "Reflection" now resides in HOL/Library.
  1745 
  1746 * Entry point to Word library now simply named "Word".
  1747 INCOMPATIBILITY.
  1748 
  1749 * Made source layout more coherent with logical distribution
  1750 structure:
  1751 
  1752     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1753     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1754     src/HOL/Library/GCD.thy ~> src/HOL/
  1755     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1756     src/HOL/Library/Parity.thy ~> src/HOL/
  1757     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1758     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1759     src/HOL/Real/Lubs.thy ~> src/HOL/
  1760     src/HOL/Real/PReal.thy ~> src/HOL/
  1761     src/HOL/Real/Rational.thy ~> src/HOL/
  1762     src/HOL/Real/RComplete.thy ~> src/HOL/
  1763     src/HOL/Real/RealDef.thy ~> src/HOL/
  1764     src/HOL/Real/RealPow.thy ~> src/HOL/
  1765     src/HOL/Real/Real.thy ~> src/HOL/
  1766     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1767     src/HOL/Complex/Complex.thy ~> src/HOL/
  1768     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1769     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1770     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1771     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1772     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1773     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1774     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1775     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1776     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1777     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1778     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1779     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1780     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1781     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1782     src/HOL/Real/Float ~> src/HOL/Library/
  1783     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1784     src/HOL/Real/RealVector.thy ~> src/HOL/
  1785 
  1786     src/HOL/arith_data.ML ~> src/HOL/Tools
  1787     src/HOL/hologic.ML ~> src/HOL/Tools
  1788     src/HOL/simpdata.ML ~> src/HOL/Tools
  1789     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1790     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1791     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1792     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1793     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1794     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1795     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1796 
  1797     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1798     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1799     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1800     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1801     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1802     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1803 
  1804 * If methods "eval" and "evaluation" encounter a structured proof
  1805 state with !!/==>, only the conclusion is evaluated to True (if
  1806 possible), avoiding strange error messages.
  1807 
  1808 * Method "sizechange" automates termination proofs using (a
  1809 modification of) the size-change principle.  Requires SAT solver.  See
  1810 src/HOL/ex/Termination.thy for examples.
  1811 
  1812 * Simplifier: simproc for let expressions now unfolds if bound
  1813 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1814 
  1815 * Method "arith": Linear arithmetic now ignores all inequalities when
  1816 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1817 
  1818 * New attribute "arith" for facts that should always be used
  1819 automatically by arithmetic. It is intended to be used locally in
  1820 proofs, e.g.
  1821 
  1822   assumes [arith]: "x > 0"
  1823 
  1824 Global usage is discouraged because of possible performance impact.
  1825 
  1826 * New classes "top" and "bot" with corresponding operations "top" and
  1827 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1828 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1829 
  1830 * Changed definition lemma "less_fun_def" in order to provide an
  1831 instance for preorders on functions; use lemma "less_le" instead.
  1832 INCOMPATIBILITY.
  1833 
  1834 * Theory Orderings: class "wellorder" moved here, with explicit
  1835 induction rule "less_induct" as assumption.  For instantiation of
  1836 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1837 INCOMPATIBILITY.
  1838 
  1839 * Theory Orderings: added class "preorder" as superclass of "order".
  1840 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1841 etc. slightly changed.  Some theorems named order_class.* now named
  1842 preorder_class.*.
  1843 
  1844 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1845 "diag" to "Id_on".
  1846 
  1847 * Theory Finite_Set: added a new fold combinator of type
  1848 
  1849   ('a => 'b => 'b) => 'b => 'a set => 'b
  1850 
  1851 Occasionally this is more convenient than the old fold combinator
  1852 which is now defined in terms of the new one and renamed to
  1853 fold_image.
  1854 
  1855 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1856 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1857 extended with further lemmas!).  At the moment both still exist but
  1858 the former will disappear at some point.
  1859 
  1860 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1861 class recpower.  Type-specific simp rules for various recpower types
  1862 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1863 
  1864 rat_power_0    -> power_0
  1865 rat_power_Suc  -> power_Suc
  1866 realpow_0      -> power_0
  1867 realpow_Suc    -> power_Suc
  1868 complexpow_0   -> power_0
  1869 complexpow_Suc -> power_Suc
  1870 power_poly_0   -> power_0
  1871 power_poly_Suc -> power_Suc
  1872 
  1873 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1874 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1875 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1876 of lemmas from Divides has been generalized from nat to class
  1877 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1878 renames resulting from duplicate elimination:
  1879 
  1880     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1881     zero_dvd_iff ~>         dvd_0_left_iff
  1882     dvd_0 ~>                dvd_0_right
  1883     DIVISION_BY_ZERO_DIV ~> div_by_0
  1884     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1885     mult_div ~>             div_mult_self2_is_id
  1886     mult_mod ~>             mod_mult_self2_is_0
  1887 
  1888 * Theory IntDiv: removed many lemmas that are instances of class-based
  1889 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1890 rename old lemmas as follows:
  1891 
  1892 dvd_diff               -> nat_dvd_diff
  1893 dvd_zminus_iff         -> dvd_minus_iff
  1894 mod_add1_eq            -> mod_add_eq
  1895 mod_mult1_eq           -> mod_mult_right_eq
  1896 mod_mult1_eq'          -> mod_mult_left_eq
  1897 mod_mult_distrib_mod   -> mod_mult_eq
  1898 nat_mod_add_left_eq    -> mod_add_left_eq
  1899 nat_mod_add_right_eq   -> mod_add_right_eq
  1900 nat_mod_div_trivial    -> mod_div_trivial
  1901 nat_mod_mod_trivial    -> mod_mod_trivial
  1902 zdiv_zadd_self1        -> div_add_self1
  1903 zdiv_zadd_self2        -> div_add_self2
  1904 zdiv_zmult_self1       -> div_mult_self2_is_id
  1905 zdiv_zmult_self2       -> div_mult_self1_is_id
  1906 zdvd_triv_left         -> dvd_triv_left
  1907 zdvd_triv_right        -> dvd_triv_right
  1908 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1909 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1910 zmod_zadd_left_eq      -> mod_add_left_eq
  1911 zmod_zadd_right_eq     -> mod_add_right_eq
  1912 zmod_zadd_self1        -> mod_add_self1
  1913 zmod_zadd_self2        -> mod_add_self2
  1914 zmod_zadd1_eq          -> mod_add_eq
  1915 zmod_zdiff1_eq         -> mod_diff_eq
  1916 zmod_zdvd_zmod         -> mod_mod_cancel
  1917 zmod_zmod_cancel       -> mod_mod_cancel
  1918 zmod_zmult_self1       -> mod_mult_self2_is_0
  1919 zmod_zmult_self2       -> mod_mult_self1_is_0
  1920 zmod_1                 -> mod_by_1
  1921 zdiv_1                 -> div_by_1
  1922 zdvd_abs1              -> abs_dvd_iff
  1923 zdvd_abs2              -> dvd_abs_iff
  1924 zdvd_refl              -> dvd_refl
  1925 zdvd_trans             -> dvd_trans
  1926 zdvd_zadd              -> dvd_add
  1927 zdvd_zdiff             -> dvd_diff
  1928 zdvd_zminus_iff        -> dvd_minus_iff
  1929 zdvd_zminus2_iff       -> minus_dvd_iff
  1930 zdvd_zmultD            -> dvd_mult_right
  1931 zdvd_zmultD2           -> dvd_mult_left
  1932 zdvd_zmult_mono        -> mult_dvd_mono
  1933 zdvd_0_right           -> dvd_0_right
  1934 zdvd_0_left            -> dvd_0_left_iff
  1935 zdvd_1_left            -> one_dvd
  1936 zminus_dvd_iff         -> minus_dvd_iff
  1937 
  1938 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1939 
  1940 * The real numbers offer decimal input syntax: 12.34 is translated
  1941 into 1234/10^2. This translation is not reversed upon output.
  1942 
  1943 * Theory Library/Polynomial defines an abstract type 'a poly of
  1944 univariate polynomials with coefficients of type 'a.  In addition to
  1945 the standard ring operations, it also supports div and mod.  Code
  1946 generation is also supported, using list-style constructors.
  1947 
  1948 * Theory Library/Inner_Product defines a class of real_inner for real
  1949 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1950 => real.  Class real_inner is a subclass of real_normed_vector from
  1951 theory RealVector.
  1952 
  1953 * Theory Library/Product_Vector provides instances for the product
  1954 type 'a * 'b of several classes from RealVector and Inner_Product.
  1955 Definitions of addition, subtraction, scalar multiplication, norms,
  1956 and inner products are included.
  1957 
  1958 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1959 addition to the field operations, numerals and case syntax are also
  1960 supported.
  1961 
  1962 * Theory Library/Diagonalize provides constructive version of Cantor's
  1963 first diagonalization argument.
  1964 
  1965 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1966 zlcm (for int); carried together from various gcd/lcm developements in
  1967 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1968 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1969 may recover tupled syntax as follows:
  1970 
  1971     hide (open) const gcd
  1972     abbreviation gcd where
  1973       "gcd == (%(a, b). GCD.gcd a b)"
  1974     notation (output)
  1975       GCD.gcd ("gcd '(_, _')")
  1976 
  1977 The same works for lcm, zgcd, zlcm.
  1978 
  1979 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1980 instantiations for algebraic structures.  Removed some duplicate
  1981 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1982 
  1983 * ML antiquotation @{code} takes a constant as argument and generates
  1984 corresponding code in background and inserts name of the corresponding
  1985 resulting ML value/function/datatype constructor binding in place.
  1986 All occurrences of @{code} with a single ML block are generated
  1987 simultaneously.  Provides a generic and safe interface for
  1988 instrumentalizing code generation.  See
  1989 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1990 In future you ought to refrain from ad-hoc compiling generated SML
  1991 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1992 cannot refer to constants for which user-defined serializations are
  1993 set.  Refer to the corresponding ML counterpart directly in that
  1994 cases.
  1995 
  1996 * Command 'rep_datatype': instead of theorem names the command now
  1997 takes a list of terms denoting the constructors of the type to be
  1998 represented as datatype.  The characteristic theorems have to be
  1999 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2000 have disappeared in favour of existing ones:
  2001 
  2002     unit_induct                 ~> unit.induct
  2003     prod_induct                 ~> prod.induct
  2004     sum_induct                  ~> sum.induct
  2005     Suc_Suc_eq                  ~> nat.inject
  2006     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2007 
  2008 
  2009 *** HOL-Algebra ***
  2010 
  2011 * New locales for orders and lattices where the equivalence relation
  2012 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2013 locales use a record structure with field eq for the equivalence.
  2014 
  2015 * New theory of factorial domains.
  2016 
  2017 * Units_l_inv and Units_r_inv are now simp rules by default.
  2018 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2019 and/or r_inv will now also require deletion of these lemmas.
  2020 
  2021 * Renamed the following theorems, INCOMPATIBILITY:
  2022 
  2023 UpperD ~> Upper_memD
  2024 LowerD ~> Lower_memD
  2025 least_carrier ~> least_closed
  2026 greatest_carrier ~> greatest_closed
  2027 greatest_Lower_above ~> greatest_Lower_below
  2028 one_zero ~> carrier_one_zero
  2029 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2030 
  2031 
  2032 *** HOL-Nominal ***
  2033 
  2034 * Nominal datatypes can now contain type-variables.
  2035 
  2036 * Commands 'nominal_inductive' and 'equivariance' work with local
  2037 theory targets.
  2038 
  2039 * Nominal primrec can now works with local theory targets and its
  2040 specification syntax now conforms to the general format as seen in
  2041 'inductive' etc.
  2042 
  2043 * Method "perm_simp" honours the standard simplifier attributes
  2044 (no_asm), (no_asm_use) etc.
  2045 
  2046 * The new predicate #* is defined like freshness, except that on the
  2047 left hand side can be a set or list of atoms.
  2048 
  2049 * Experimental command 'nominal_inductive2' derives strong induction
  2050 principles for inductive definitions.  In contrast to
  2051 'nominal_inductive', which can only deal with a fixed number of
  2052 binders, it can deal with arbitrary expressions standing for sets of
  2053 atoms to be avoided.  The only inductive definition we have at the
  2054 moment that needs this generalisation is the typing rule for Lets in
  2055 the algorithm W:
  2056 
  2057  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2058  -----------------------------------------------------------------
  2059          Gamma |- Let x be t1 in t2 : T2
  2060 
  2061 In this rule one wants to avoid all the binders that are introduced by
  2062 "close Gamma T1".  We are looking for other examples where this
  2063 feature might be useful.  Please let us know.
  2064 
  2065 
  2066 *** HOLCF ***
  2067 
  2068 * Reimplemented the simplification procedure for proving continuity
  2069 subgoals.  The new simproc is extensible; users can declare additional
  2070 continuity introduction rules with the attribute [cont2cont].
  2071 
  2072 * The continuity simproc now uses a different introduction rule for
  2073 solving continuity subgoals on terms with lambda abstractions.  In
  2074 some rare cases the new simproc may fail to solve subgoals that the
  2075 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2076 Potential INCOMPATIBILITY.
  2077 
  2078 * Command 'fixrec': specification syntax now conforms to the general
  2079 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2080 examples.  INCOMPATIBILITY.
  2081 
  2082 
  2083 *** ZF ***
  2084 
  2085 * Proof of Zorn's Lemma for partial orders.
  2086 
  2087 
  2088 *** ML ***
  2089 
  2090 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2091 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2092 depends on multithreading, so timouts will not work before Poly/ML
  2093 5.2.1!
  2094 
  2095 * High-level support for concurrent ML programming, see
  2096 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2097 particularly convenient to organize independent functional
  2098 computations.  The concept of "synchronized variables" provides a
  2099 higher-order interface for components with shared state, avoiding the
  2100 delicate details of mutexes and condition variables.  (Requires
  2101 Poly/ML 5.2.1 or later.)
  2102 
  2103 * ML bindings produced via Isar commands are stored within the Isar
  2104 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2105 become thread-safe and work with undo as expected (concerning
  2106 top-level bindings, not side-effects on global references).
  2107 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2108 compiler at runtime; really global bindings need to be given outside a
  2109 theory.  (Requires Poly/ML 5.2 or later.)
  2110 
  2111 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2112 context.  Top-level ML bindings are stored within the proof context in
  2113 a purely sequential fashion, disregarding the nested proof structure.
  2114 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2115 proof.  (Requires Poly/ML 5.2 or later.)
  2116 
  2117 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2118 and Method.setup, as well as Isar commands 'attribute_setup' and
  2119 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2120 existing code accordingly, or use plain 'setup' together with old
  2121 Method.add_method.
  2122 
  2123 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2124 to 'a -> thm, while results are always tagged with an authentic oracle
  2125 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2126 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2127 accordingly.  Note that extra performance may be gained by producing
  2128 the cterm carefully, avoiding slow Thm.cterm_of.
  2129 
  2130 * Simplified interface for defining document antiquotations via
  2131 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2132 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2133 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2134 examples.
  2135 
  2136 * More systematic treatment of long names, abstract name bindings, and
  2137 name space operations.  Basic operations on qualified names have been
  2138 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2139 Long_Name.append.  Old type bstring has been mostly replaced by
  2140 abstract type binding (see structure Binding), which supports precise
  2141 qualification by packages and local theory targets, as well as proper
  2142 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2143 bstring values into Binding.name, or better pass through abstract
  2144 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2145 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2146 
  2147 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2148 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2149 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2150 
  2151 * Disposed old type and term read functions (Sign.read_def_typ,
  2152 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2153 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2154 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2155 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2156 resort for legacy applications.
  2157 
  2158 * Disposed old declarations, tactics, tactic combinators that refer to
  2159 the simpset or claset of an implicit theory (such as Addsimps,
  2160 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2161 embedded ML text, or local_simpset_of with a proper context passed as
  2162 explicit runtime argument.
  2163 
  2164 * Rules and tactics that read instantiations (read_instantiate,
  2165 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2166 context, which is required for parsing and type-checking.  Moreover,
  2167 the variables are specified as plain indexnames, not string encodings
  2168 thereof.  INCOMPATIBILITY.
  2169 
  2170 * Generic Toplevel.add_hook interface allows to analyze the result of
  2171 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2172 for theorem dependency output of transactions resulting in a new
  2173 theory state.
  2174 
  2175 * ML antiquotations: block-structured compilation context indicated by
  2176 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2177 
  2178   @{binding name}                         - basic name binding
  2179   @{let ?pat = term}                      - term abbreviation (HO matching)
  2180   @{note name = fact}                     - fact abbreviation
  2181   @{thm fact}                             - singleton fact (with attributes)
  2182   @{thms fact}                            - general fact (with attributes)
  2183   @{lemma prop by method}                 - singleton goal
  2184   @{lemma prop by meth1 meth2}            - singleton goal
  2185   @{lemma prop1 ... propN by method}      - general goal
  2186   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2187   @{lemma (open) ...}                     - open derivation
  2188 
  2189 
  2190 *** System ***
  2191 
  2192 * The Isabelle "emacs" tool provides a specific interface to invoke
  2193 Proof General / Emacs, with more explicit failure if that is not
  2194 installed (the old isabelle-interface script silently falls back on
  2195 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2196 installation location of the Proof General distribution.
  2197 
  2198 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2199 the Isabelle process into a JVM/Scala application.  See
  2200 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2201 process wrapper has been discontinued.)
  2202 
  2203 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2204 
  2205 * Various status messages (with exact source position information) are
  2206 emitted, if proper markup print mode is enabled.  This allows
  2207 user-interface components to provide detailed feedback on internal
  2208 prover operations.
  2209 
  2210 
  2211 
  2212 New in Isabelle2008 (June 2008)
  2213 -------------------------------
  2214 
  2215 *** General ***
  2216 
  2217 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2218 and updated, with formally checked references as hyperlinks.
  2219 
  2220 * Theory loader: use_thy (and similar operations) no longer set the
  2221 implicit ML context, which was occasionally hard to predict and in
  2222 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2223 provides a proper context already.
  2224 
  2225 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2226 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2227 'use' within a theory file will do the job.
  2228 
  2229 * Name space merge now observes canonical order, i.e. the second space
  2230 is inserted into the first one, while existing entries in the first
  2231 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2232 swap theory imports.
  2233 
  2234 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2235 INCOMPATIBILITY in identifier syntax etc.
  2236 
  2237 * Outer syntax: string tokens no longer admit escaped white space,
  2238 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2239 white space without escapes.
  2240 
  2241 * Outer syntax: string tokens may contain arbitrary character codes
  2242 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2243 "foo_bar".
  2244 
  2245 
  2246 *** Pure ***
  2247 
  2248 * Context-dependent token translations.  Default setup reverts locally
  2249 fixed variables, and adds hilite markup for undeclared frees.
  2250 
  2251 * Unused theorems can be found using the new command 'unused_thms'.
  2252 There are three ways of invoking it:
  2253 
  2254 (1) unused_thms
  2255      Only finds unused theorems in the current theory.
  2256 
  2257 (2) unused_thms thy_1 ... thy_n -
  2258      Finds unused theorems in the current theory and all of its ancestors,
  2259      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2260 
  2261 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2262      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2263      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2264      their ancestors.
  2265 
  2266 In order to increase the readability of the list produced by
  2267 unused_thms, theorems that have been created by a particular instance
  2268 of a theory command such as 'inductive' or 'function' are considered
  2269 to belong to the same "group", meaning that if at least one theorem in
  2270 this group is used, the other theorems in the same group are no longer
  2271 reported as unused.  Moreover, if all theorems in the group are
  2272 unused, only one theorem in the group is displayed.
  2273 
  2274 Note that proof objects have to be switched on in order for
  2275 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2276 usually the case when using Proof General with the default settings).
  2277 
  2278 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2279 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2280 duplicate fact bindings, or even accidental fact duplications.  Note
  2281 that tools may maintain dynamically scoped facts systematically, using
  2282 PureThy.add_thms_dynamic.
  2283 
  2284 * Command 'hide' now allows to hide from "fact" name space as well.
  2285 
  2286 * Eliminated destructive theorem database, simpset, claset, and
  2287 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2288 update of theories within ML code.
  2289 
  2290 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2291 INCOMPATIBILITY, object-logics depending on former Pure require
  2292 additional setup PureThy.old_appl_syntax_setup; object-logics
  2293 depending on former CPure need to refer to Pure.
  2294 
  2295 * Commands 'use' and 'ML' are now purely functional, operating on
  2296 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2297 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2298 INCOMPATIBILITY.
  2299 
  2300 * Command 'setup': discontinued implicit version with ML reference.
  2301 
  2302 * Instantiation target allows for simultaneous specification of class
  2303 instance operations together with an instantiation proof.
  2304 Type-checking phase allows to refer to class operations uniformly.
  2305 See src/HOL/Complex/Complex.thy for an Isar example and
  2306 src/HOL/Library/Eval.thy for an ML example.
  2307 
  2308 * Indexing of literal facts: be more serious about including only
  2309 facts from the visible specification/proof context, but not the
  2310 background context (locale etc.).  Affects `prop` notation and method
  2311 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2312 situations.
  2313 
  2314 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2315 "(open)" option, which used to expose internal bound variables to the
  2316 proof text.
  2317 
  2318 * Isar statements: removed obsolete case "rule_context".
  2319 INCOMPATIBILITY, better use explicit fixes/assumes.
  2320 
  2321 * Locale proofs: default proof step now includes 'unfold_locales';
  2322 hence 'proof' without argument may be used to unfold locale
  2323 predicates.
  2324 
  2325 
  2326 *** Document preparation ***
  2327 
  2328 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2329 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2330 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2331 spot); renamed link color from "darkblue" to "linkcolor" (default
  2332 value unchanged, can be redefined via \definecolor); no longer sets
  2333 "a4paper" option (unnecessary or even intrusive).
  2334 
  2335 * Antiquotation @{lemma A method} proves proposition A by the given
  2336 method (either a method name or a method name plus (optional) method
  2337 arguments in parentheses) and prints A just like @{prop A}.
  2338 
  2339 
  2340 *** HOL ***
  2341 
  2342 * New primrec package.  Specification syntax conforms in style to
  2343 definition/function/....  No separate induction rule is provided.  The
  2344 "primrec" command distinguishes old-style and new-style specifications
  2345 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2346 When adjusting theories, beware: constants stemming from new-style
  2347 primrec specifications have authentic syntax.
  2348 
  2349 * Metis prover is now an order of magnitude faster, and also works
  2350 with multithreading.
  2351 
  2352 * Metis: the maximum number of clauses that can be produced from a
  2353 theorem is now given by the attribute max_clauses.  Theorems that
  2354 exceed this number are ignored, with a warning printed.
  2355 
  2356 * Sledgehammer no longer produces structured proofs by default. To
  2357 enable, declare [[sledgehammer_full = true]].  Attributes
  2358 reconstruction_modulus, reconstruction_sorts renamed
  2359 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2360 
  2361 * Method "induct_scheme" derives user-specified induction rules
  2362 from well-founded induction and completeness of patterns. This factors
  2363 out some operations that are done internally by the function package
  2364 and makes them available separately.  See
  2365 src/HOL/ex/Induction_Scheme.thy for examples.
  2366 
  2367 * More flexible generation of measure functions for termination
  2368 proofs: Measure functions can be declared by proving a rule of the
  2369 form "is_measure f" and giving it the [measure_function] attribute.
  2370 The "is_measure" predicate is logically meaningless (always true), and
  2371 just guides the heuristic.  To find suitable measure functions, the
  2372 termination prover sets up the goal "is_measure ?f" of the appropriate
  2373 type and generates all solutions by prolog-style backwards proof using
  2374 the declared rules.
  2375 
  2376 This setup also deals with rules like 
  2377 
  2378   "is_measure f ==> is_measure (list_size f)"
  2379 
  2380 which accommodates nested datatypes that recurse through lists.
  2381 Similar rules are predeclared for products and option types.
  2382 
  2383 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2384 
  2385   INCOMPATIBILITIES:
  2386 
  2387   - Definitions of overloaded constants on sets have to be replaced by
  2388     definitions on => and bool.
  2389 
  2390   - Some definitions of overloaded operators on sets can now be proved
  2391     using the definitions of the operators on => and bool.  Therefore,
  2392     the following theorems have been renamed:
  2393 
  2394       subset_def   -> subset_eq
  2395       psubset_def  -> psubset_eq
  2396       set_diff_def -> set_diff_eq
  2397       Compl_def    -> Compl_eq
  2398       Sup_set_def  -> Sup_set_eq
  2399       Inf_set_def  -> Inf_set_eq
  2400       sup_set_def  -> sup_set_eq
  2401       inf_set_def  -> inf_set_eq
  2402 
  2403   - Due to the incompleteness of the HO unification algorithm, some
  2404     rules such as subst may require manual instantiation, if some of
  2405     the unknowns in the rule is a set.
  2406 
  2407   - Higher order unification and forward proofs:
  2408     The proof pattern
  2409 
  2410       have "P (S::'a set)" <...>
  2411       then have "EX S. P S" ..
  2412 
  2413     no longer works (due to the incompleteness of the HO unification
  2414     algorithm) and must be replaced by the pattern
  2415 
  2416       have "EX S. P S"
  2417       proof
  2418         show "P S" <...>
  2419       qed
  2420 
  2421   - Calculational reasoning with subst (or similar rules):
  2422     The proof pattern
  2423 
  2424       have "P (S::'a set)" <...>
  2425       also have "S = T" <...>
  2426       finally have "P T" .
  2427 
  2428     no longer works (for similar reasons as the previous example) and
  2429     must be replaced by something like
  2430 
  2431       have "P (S::'a set)" <...>
  2432       moreover have "S = T" <...>
  2433       ultimately have "P T" by simp
  2434 
  2435   - Tactics or packages written in ML code:
  2436     Code performing pattern matching on types via
  2437 
  2438       Type ("set", [T]) => ...
  2439 
  2440     must be rewritten. Moreover, functions like strip_type or
  2441     binder_types no longer return the right value when applied to a
  2442     type of the form
  2443 
  2444       T1 => ... => Tn => U => bool
  2445 
  2446     rather than
  2447 
  2448       T1 => ... => Tn => U set
  2449 
  2450 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2451 Wellfounded_Relations to theory Wellfounded.
  2452 
  2453 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2454 
  2455 * Class finite no longer treats UNIV as class parameter.  Use class
  2456 enum from theory Library/Enum instead to achieve a similar effect.
  2457 INCOMPATIBILITY.
  2458 
  2459 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2460 and "Cons".  INCOMPATIBILITY.
  2461 
  2462 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2463 Potential INCOMPATIBILITY.
  2464 
  2465 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2466 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2467 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2468 
  2469 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2470 the same name in theory Orderings:
  2471 
  2472   less_trans
  2473   less_linear
  2474   le_imp_less_or_eq
  2475   le_less_trans
  2476   less_le_trans
  2477   less_not_sym
  2478   less_asym
  2479 
  2480 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2481 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2482 and different variable names.
  2483 
  2484 * Library/Option_ord.thy: Canonical order on option type.
  2485 
  2486 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2487 finite maps.
  2488 
  2489 * Library/Countable.thy: Type class for countable types.
  2490 
  2491 * Theory Int: The representation of numerals has changed.  The infix
  2492 operator BIT and the bit datatype with constructors B0 and B1 have
  2493 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2494 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2495 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2496 accordingly.
  2497 
  2498 * Theory Nat: definition of <= and < on natural numbers no longer
  2499 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2500 le_def and less_def have disappeared.  Consider lemmas not_less
  2501 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2502 
  2503 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2504 (whose purpose mainly is for various fold_set functionals) have been
  2505 abandoned in favor of the existing algebraic classes
  2506 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2507 lower_semilattice (resp. upper_semilattice) and linorder.
  2508 INCOMPATIBILITY.
  2509 
  2510 * Theory Transitive_Closure: induct and cases rules now declare proper
  2511 case_names ("base" and "step").  INCOMPATIBILITY.
  2512 
  2513 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2514 lattices.  The form set-specific version is available as
  2515 Inductive.lfp_ordinal_induct_set.
  2516 
  2517 * Renamed theorems "power.simps" to "power_int.simps".
  2518 INCOMPATIBILITY.
  2519 
  2520 * Class semiring_div provides basic abstract properties of semirings
  2521 with division and modulo operations.  Subsumes former class dvd_mod.
  2522 
  2523 * Merged theories IntDef, Numeral and IntArith into unified theory
  2524 Int.  INCOMPATIBILITY.
  2525 
  2526 * Theory Library/Code_Index: type "index" now represents natural
  2527 numbers rather than integers.  INCOMPATIBILITY.
  2528 
  2529 * New class "uminus" with operation "uminus" (split of from class
  2530 "minus" which now only has operation "minus", binary).
  2531 INCOMPATIBILITY.
  2532 
  2533 * Constants "card", "internal_split", "option_map" now with authentic
  2534 syntax.  INCOMPATIBILITY.
  2535 
  2536 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2537 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2538 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2539 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2540 Sup_set_def, le_def, less_def, option_map_def now with object
  2541 equality.  INCOMPATIBILITY.
  2542 
  2543 * Records. Removed K_record, and replaced it by pure lambda term
  2544 %x. c. The simplifier setup is now more robust against eta expansion.
  2545 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2546 
  2547 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2548 
  2549 * Library/ListVector: new theory of arithmetic vector operations.
  2550 
  2551 * Library/Order_Relation: new theory of various orderings as sets of
  2552 pairs.  Defines preorders, partial orders, linear orders and
  2553 well-orders on sets and on types.
  2554 
  2555 
  2556 *** ZF ***
  2557 
  2558 * Renamed some theories to allow to loading both ZF and HOL in the
  2559 same session:
  2560 
  2561   Datatype  -> Datatype_ZF
  2562   Inductive -> Inductive_ZF
  2563   Int       -> Int_ZF
  2564   IntDiv    -> IntDiv_ZF
  2565   Nat       -> Nat_ZF
  2566   List      -> List_ZF
  2567   Main      -> Main_ZF
  2568 
  2569 INCOMPATIBILITY: ZF theories that import individual theories below
  2570 Main might need to be adapted.  Regular theory Main is still
  2571 available, as trivial extension of Main_ZF.
  2572 
  2573 
  2574 *** ML ***
  2575 
  2576 * ML within Isar: antiquotation @{const name} or @{const
  2577 name(typargs)} produces statically-checked Const term.
  2578 
  2579 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2580 (of the same name).  Removed obsolete print command.
  2581 
  2582 * Removed obsolete "use_legacy_bindings" function.
  2583 
  2584 * The ``print mode'' is now a thread-local value derived from a global
  2585 template (the former print_mode reference), thus access becomes
  2586 non-critical.  The global print_mode reference is for session
  2587 management only; user-code should use print_mode_value,
  2588 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2589 
  2590 * Functions system/system_out provide a robust way to invoke external
  2591 shell commands, with propagation of interrupts (requires Poly/ML
  2592 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2593 
  2594 
  2595 *** System ***
  2596 
  2597 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2598 in accordance with Proof General 3.7, which prefers GNU emacs.
  2599 
  2600 * isatool tty runs Isabelle process with plain tty interaction;
  2601 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2602 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2603 
  2604 * isatool browser now works with Cygwin as well, using general
  2605 "javapath" function defined in Isabelle process environment.
  2606 
  2607 * YXML notation provides a simple and efficient alternative to
  2608 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2609 isatool yxml as described in the Isabelle system manual.
  2610 
  2611 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2612 provides general wrapper for managing an Isabelle process in a robust
  2613 fashion, with ``cooked'' output from stdin/stderr.
  2614 
  2615 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2616 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2617 
  2618 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2619 way of changing the user's settings is via
  2620 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2621 script.
  2622 
  2623 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2624 cores of the underlying machine, which is a good starting point for
  2625 optimal performance tuning.  The corresponding usedir option -M allows
  2626 "max" as an alias for "0".  WARNING: does not work on certain versions
  2627 of Mac OS (with Poly/ML 5.1).
  2628 
  2629 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2630 adverse effect of Isabelle flooding interactive front-ends (notably
  2631 ProofGeneral / XEmacs).
  2632 
  2633 
  2634 
  2635 New in Isabelle2007 (November 2007)
  2636 -----------------------------------
  2637 
  2638 *** General ***
  2639 
  2640 * More uniform information about legacy features, notably a
  2641 warning/error of "Legacy feature: ...", depending on the state of the
  2642 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2643 legacy features will disappear eventually.
  2644 
  2645 * Theory syntax: the header format ``theory A = B + C:'' has been
  2646 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2647 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2648 
  2649 * Theory syntax: the old non-Isar theory file format has been
  2650 discontinued altogether.  Note that ML proof scripts may still be used
  2651 with Isar theories; migration is usually quite simple with the ML
  2652 function use_legacy_bindings.  INCOMPATIBILITY.
  2653 
  2654 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2655 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2656 quotes.
  2657 
  2658 * Theory loader: be more serious about observing the static theory
  2659 header specifications (including optional directories), but not the
  2660 accidental file locations of previously successful loads.  The strict
  2661 update policy of former update_thy is now already performed by
  2662 use_thy, so the former has been removed; use_thys updates several
  2663 theories simultaneously, just as 'imports' within a theory header
  2664 specification, but without merging the results.  Potential
  2665 INCOMPATIBILITY: may need to refine theory headers and commands
  2666 ROOT.ML which depend on load order.
  2667 
  2668 * Theory loader: optional support for content-based file
  2669 identification, instead of the traditional scheme of full physical
  2670 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2671 (cf. the system manual).  The new scheme allows to work with
  2672 non-finished theories in persistent session images, such that source
  2673 files may be moved later on without requiring reloads.
  2674 
  2675 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2676 file (with the same base name as the theory) are considered a legacy
  2677 feature, which will disappear eventually. Even now, the theory loader
  2678 no longer maintains dependencies on such files.
  2679 
  2680 * Syntax: the scope for resolving ambiguities via type-inference is
  2681 now limited to individual terms, instead of whole simultaneous
  2682 specifications as before. This greatly reduces the complexity of the
  2683 syntax module and improves flexibility by separating parsing and
  2684 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2685 'fixes' etc.) are required in rare situations.
  2686 
  2687 * Syntax: constants introduced by new-style packages ('definition',
  2688 'abbreviation' etc.) are passed through the syntax module in
  2689 ``authentic mode''. This means that associated mixfix annotations
  2690 really stick to such constants, independently of potential name space
  2691 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2692 trees are represented slightly differently, may need to adapt syntax
  2693 translations accordingly. Use CONST marker in 'translations' and
  2694 @{const_syntax} antiquotation in 'parse_translation' etc.
  2695 
  2696 * Legacy goal package: reduced interface to the bare minimum required
  2697 to keep existing proof scripts running.  Most other user-level
  2698 functions are now part of the OldGoals structure, which is *not* open
  2699 by default (consider isatool expandshort before open OldGoals).
  2700 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2701 these tend to cause confusion about the actual goal (!) context being
  2702 used here, which is not necessarily the same as the_context().
  2703 
  2704 * Command 'find_theorems': supports "*" wild-card in "name:"
  2705 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2706 support a specific search form (see ProofGeneral/CHANGES).
  2707 
  2708 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2709 by default, which means that "prems" (and also "fixed variables") are
  2710 suppressed from proof state output.  Note that the ProofGeneral
  2711 settings mechanism allows to change and save options persistently, but
  2712 older versions of Isabelle will fail to start up if a negative prems
  2713 limit is imposed.
  2714 
  2715 * Local theory targets may be specified by non-nested blocks of
  2716 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2717 contain definitions, theorems etc., including any derived mechanism
  2718 that has been implemented on top of these primitives.  This concept
  2719 generalizes the existing ``theorem (in ...)'' towards more versatility
  2720 and scalability.
  2721 
  2722 * Proof General interface: proper undo of final 'end' command;
  2723 discontinued Isabelle/classic mode (ML proof scripts).
  2724 
  2725 
  2726 *** Document preparation ***
  2727 
  2728 * Added antiquotation @{theory name} which prints the given name,
  2729 after checking that it refers to a valid ancestor theory in the
  2730 current context.
  2731 
  2732 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2733 check the given source text as ML type/structure, printing verbatim.
  2734 
  2735 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2736 "c args == rhs" given in the current context.  (Any number of
  2737 arguments may be given on the LHS.)
  2738 
  2739 
  2740 *** Pure ***
  2741 
  2742 * The 'class' package offers a combination of axclass and locale to
  2743 achieve Haskell-like type classes in Isabelle.  Definitions and
  2744 theorems within a class context produce both relative results (with
  2745 implicit parameters according to the locale context), and polymorphic
  2746 constants with qualified polymorphism (according to the class
  2747 context).  Within the body context of a 'class' target, a separate
  2748 syntax layer ("user space type system") takes care of converting
  2749 between global polymorphic consts and internal locale representation.
  2750 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2751 "isatool doc classes" provides a tutorial.
  2752 
  2753 * Generic code generator framework allows to generate executable
  2754 code for ML and Haskell (including Isabelle classes).  A short usage
  2755 sketch:
  2756 
  2757     internal compilation:
  2758         export_code <list of constants (term syntax)> in SML
  2759     writing SML code to a file:
  2760         export_code <list of constants (term syntax)> in SML <filename>
  2761     writing OCaml code to a file:
  2762         export_code <list of constants (term syntax)> in OCaml <filename>
  2763     writing Haskell code to a bunch of files:
  2764         export_code <list of constants (term syntax)> in Haskell <filename>
  2765 
  2766     evaluating closed propositions to True/False using code generation:
  2767         method ``eval''
  2768 
  2769 Reasonable default setup of framework in HOL.
  2770 
  2771 Theorem attributs for selecting and transforming function equations theorems:
  2772 
  2773     [code fun]:        select a theorem as function equation for a specific constant
  2774     [code fun del]:    deselect a theorem as function equation for a specific constant
  2775     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2776     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2777 
  2778 User-defined serializations (target in {SML, OCaml, Haskell}):
  2779 
  2780     code_const <and-list of constants (term syntax)>
  2781       {(target) <and-list of const target syntax>}+
  2782 
  2783     code_type <and-list of type constructors>
  2784       {(target) <and-list of type target syntax>}+
  2785 
  2786     code_instance <and-list of instances>
  2787       {(target)}+
  2788         where instance ::= <type constructor> :: <class>
  2789 
  2790     code_class <and_list of classes>
  2791       {(target) <and-list of class target syntax>}+
  2792         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2793 
  2794 code_instance and code_class only are effective to target Haskell.
  2795 
  2796 For example usage see src/HOL/ex/Codegenerator.thy and
  2797 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2798 generation from Isabelle/HOL theories is available via "isatool doc
  2799 codegen".
  2800 
  2801 * Code generator: consts in 'consts_code' Isar commands are now
  2802 referred to by usual term syntax (including optional type
  2803 annotations).
  2804 
  2805 * Command 'no_translations' removes translation rules from theory
  2806 syntax.
  2807 
  2808 * Overloaded definitions are now actually checked for acyclic
  2809 dependencies.  The overloading scheme is slightly more general than
  2810 that of Haskell98, although Isabelle does not demand an exact
  2811 correspondence to type class and instance declarations.
  2812 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2813 exotic versions of overloading -- at the discretion of the user!
  2814 
  2815 Polymorphic constants are represented via type arguments, i.e. the
  2816 instantiation that matches an instance against the most general
  2817 declaration given in the signature.  For example, with the declaration
  2818 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2819 as c(nat).  Overloading is essentially simultaneous structural
  2820 recursion over such type arguments.  Incomplete specification patterns
  2821 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2822 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2823 Command 'print_theory' outputs the normalized system of recursive
  2824 equations, see section "definitions".
  2825 
  2826 * Configuration options are maintained within the theory or proof
  2827 context (with name and type bool/int/string), providing a very simple
  2828 interface to a poor-man's version of general context data.  Tools may
  2829 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2830 these values using Config.get etc.  Users may change options via an
  2831 associated attribute of the same name.  This form of context
  2832 declaration works particularly well with commands 'declare' or
  2833 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2834 very easy to avoid global references, which would not observe Isar
  2835 toplevel undo/redo and fail to work with multithreading.
  2836 
  2837 Various global ML references of Pure and HOL have been turned into
  2838 configuration options:
  2839 
  2840   Unify.search_bound		unify_search_bound
  2841   Unify.trace_bound		unify_trace_bound
  2842   Unify.trace_simp		unify_trace_simp
  2843   Unify.trace_types		unify_trace_types
  2844   Simplifier.simp_depth_limit	simp_depth_limit
  2845   Blast.depth_limit		blast_depth_limit
  2846   DatatypeProp.dtK		datatype_distinctness_limit
  2847   fast_arith_neq_limit  	fast_arith_neq_limit
  2848   fast_arith_split_limit	fast_arith_split_limit
  2849 
  2850 * Named collections of theorems may be easily installed as context
  2851 data using the functor NamedThmsFun (see also
  2852 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2853 attributes; there is also a toplevel print command.  This facility is
  2854 just a common case of general context data, which is the preferred way
  2855 for anything more complex than just a list of facts in canonical
  2856 order.
  2857 
  2858 * Isar: command 'declaration' augments a local theory by generic
  2859 declaration functions written in ML.  This enables arbitrary content
  2860 being added to the context, depending on a morphism that tells the
  2861 difference of the original declaration context wrt. the application
  2862 context encountered later on.
  2863 
  2864 * Isar: proper interfaces for simplification procedures.  Command
  2865 'simproc_setup' declares named simprocs (with match patterns, and body
  2866 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2867 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2868 
  2869 * Isar: an extra pair of brackets around attribute declarations
  2870 abbreviates a theorem reference involving an internal dummy fact,
  2871 which will be ignored later --- only the effect of the attribute on
  2872 the background context will persist.  This form of in-place
  2873 declarations is particularly useful with commands like 'declare' and
  2874 'using', for example ``have A using [[simproc a]] by simp''.
  2875 
  2876 * Isar: method "assumption" (and implicit closing of subproofs) now
  2877 takes simple non-atomic goal assumptions into account: after applying
  2878 an assumption as a rule the resulting subgoals are solved by atomic
  2879 assumption steps.  This is particularly useful to finish 'obtain'
  2880 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2881 without referring to the original premise "!!x. P x ==> thesis" in the
  2882 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2883 more permissive.
  2884 
  2885 * Isar: implicit use of prems from the Isar proof context is
  2886 considered a legacy feature.  Common applications like ``have A .''
  2887 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2888 referencing facts explicitly here improves readability and
  2889 maintainability of proof texts.
  2890 
  2891 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2892 the obtained context from the course of reasoning!  For example:
  2893 
  2894   assume "EX x y. A x & B y"   -- "any previous fact"
  2895   then guess x and y by clarify
  2896 
  2897 This technique is potentially adventurous, depending on the facts and
  2898 proof tools being involved here.
  2899 
  2900 * Isar: known facts from the proof context may be specified as literal
  2901 propositions, using ASCII back-quote syntax.  This works wherever
  2902 named facts used to be allowed so far, in proof commands, proof
  2903 methods, attributes etc.  Literal facts are retrieved from the context
  2904 according to unification of type and term parameters.  For example,
  2905 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2906 theorems in the current context, then these are valid literal facts:
  2907 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2908 
  2909 There is also a proof method "fact" which does the same composition
  2910 for explicit goal states, e.g. the following proof texts coincide with
  2911 certain special cases of literal facts:
  2912 
  2913   have "A" by fact                 ==  note `A`
  2914   have "A ==> B" by fact           ==  note `A ==> B`
  2915   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2916   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2917 
  2918 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2919 outer syntax.  Thus symbolic identifiers may be used without
  2920 additional white space in declarations like this: ``assume *: A''.
  2921 
  2922 * Isar: 'print_facts' prints all local facts of the current context,
  2923 both named and unnamed ones.
  2924 
  2925 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2926 
  2927   def x == "t" and y == "u"
  2928 
  2929 * Isar: added command 'unfolding', which is structurally similar to
  2930 'using', but affects both the goal state and facts by unfolding given
  2931 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2932 'unfolded' attribute may be replaced by first-class proof text.
  2933 
  2934 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2935 and command 'unfolding' now all support object-level equalities
  2936 (potentially conditional).  The underlying notion of rewrite rule is
  2937 analogous to the 'rule_format' attribute, but *not* that of the
  2938 Simplifier (which is usually more generous).
  2939 
  2940 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2941 premises of a theorem by n. Useful in conjunction with drule.
  2942 
  2943 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2944 method expression within a sandbox consisting of the first N
  2945 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2946 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2947 simplifies all new goals that emerge from applying rule foo to the
  2948 originally first one.
  2949 
  2950 * Isar: schematic goals are no longer restricted to higher-order
  2951 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2952 expected.
  2953 
  2954 * Isar: the conclusion of a long theorem statement is now either
  2955 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2956 (essentially a disjunction of cases with local parameters and
  2957 assumptions).  The latter allows to express general elimination rules
  2958 adequately; in this notation common elimination rules look like this:
  2959 
  2960   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2961     assumes "EX x. P x"
  2962     obtains x where "P x"
  2963 
  2964   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2965     assumes "A & B"
  2966     obtains A and B
  2967 
  2968   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2969     assumes "A | B"
  2970     obtains
  2971       A
  2972     | B
  2973 
  2974 The subsequent classical rules even refer to the formal "thesis"
  2975 explicitly:
  2976 
  2977   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2978     obtains "~ thesis"
  2979 
  2980   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2981     obtains "thesis ==> something"
  2982 
  2983 The actual proof of an 'obtains' statement is analogous to that of the
  2984 Isar proof element 'obtain', only that there may be several cases.
  2985 Optional case names may be specified in parentheses; these will be
  2986 available both in the present proof and as annotations in the
  2987 resulting rule, for later use with the 'cases' method (cf. attribute
  2988 case_names).
  2989 
  2990 * Isar: the assumptions of a long theorem statement are available as
  2991 "assms" fact in the proof context.  This is more appropriate than the
  2992 (historical) "prems", which refers to all assumptions of the current
  2993 context, including those from the target locale, proof body etc.
  2994 
  2995 * Isar: 'print_statement' prints theorems from the current theory or
  2996 proof context in long statement form, according to the syntax of a
  2997 top-level lemma.
  2998 
  2999 * Isar: 'obtain' takes an optional case name for the local context
  3000 introduction rule (default "that").
  3001 
  3002 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3003 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3004 to occur.
  3005 
  3006 * Pure: syntax "CONST name" produces a fully internalized constant
  3007 according to the current context.  This is particularly useful for
  3008 syntax translations that should refer to internal constant
  3009 representations independently of name spaces.
  3010 
  3011 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3012 instead of "FOO ". This allows multiple binder declarations to coexist
  3013 in the same context.  INCOMPATIBILITY.
  3014 
  3015 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3016 primitive that also works in a locale context (both for constants and
  3017 fixed variables). Type declaration and internal syntactic representation
  3018 of given constants retrieved from the context. Likewise, the
  3019 'no_notation' command allows to remove given syntax annotations from the
  3020 current context.
  3021 
  3022 * Isar/locales: new derived specification elements 'axiomatization',
  3023 'definition', 'abbreviation', which support type-inference, admit
  3024 object-level specifications (equality, equivalence).  See also the
  3025 isar-ref manual.  Examples:
  3026 
  3027   axiomatization
  3028     eq  (infix "===" 50) where
  3029     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3030 
  3031   definition "f x y = x + y + 1"
  3032   definition g where "g x = f x x"
  3033 
  3034   abbreviation
  3035     neq  (infix "=!=" 50) where
  3036     "x =!= y == ~ (x === y)"
  3037 
  3038 These specifications may be also used in a locale context.  Then the
  3039 constants being introduced depend on certain fixed parameters, and the
  3040 constant name is qualified by the locale base name.  An internal
  3041 abbreviation takes care for convenient input and output, making the
  3042 parameters implicit and using the original short name.  See also
  3043 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3044 entities from a monomorphic theory.
  3045 
  3046 Presently, abbreviations are only available 'in' a target locale, but
  3047 not inherited by general import expressions.  Also note that
  3048 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3049 'translations' in common applications.  The "no_abbrevs" print mode
  3050 prevents folding of abbreviations in term output.
  3051 
  3052 Concrete syntax is attached to specified constants in internal form,
  3053 independently of name spaces.  The parse tree representation is
  3054 slightly different -- use 'notation' instead of raw 'syntax', and
  3055 'translations' with explicit "CONST" markup to accommodate this.
  3056 
  3057 * Pure/Isar: unified syntax for new-style specification mechanisms
  3058 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3059 full type inference and dummy patterns ("_").  For example:
  3060 
  3061   definition "K x _ = x"
  3062 
  3063   inductive conj for A B
  3064   where "A ==> B ==> conj A B"
  3065 
  3066 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3067 the current context.  Print mode "no_abbrevs" prevents inversion of
  3068 abbreviations on output.
  3069 
  3070 * Isar/locales: improved parameter handling: use of locales "var" and
  3071 "struct" no longer necessary; - parameter renamings are no longer
  3072 required to be injective.  For example, this allows to define
  3073 endomorphisms as locale endom = homom mult mult h.
  3074 
  3075 * Isar/locales: changed the way locales with predicates are defined.
  3076 Instead of accumulating the specification, the imported expression is
  3077 now an interpretation.  INCOMPATIBILITY: different normal form of
  3078 locale expressions.  In particular, in interpretations of locales with
  3079 predicates, goals repesenting already interpreted fragments are not
  3080 removed automatically.  Use methods `intro_locales' and
  3081 `unfold_locales'; see below.
  3082 
  3083 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3084 provide backward reasoning on locales predicates.  The methods are
  3085 aware of interpretations and discharge corresponding goals.
  3086 `intro_locales' is less aggressive then `unfold_locales' and does not
  3087 unfold predicates to assumptions.
  3088 
  3089 * Isar/locales: the order in which locale fragments are accumulated
  3090 has changed.  This enables to override declarations from fragments due
  3091 to interpretations -- for example, unwanted simp rules.
  3092 
  3093 * Isar/locales: interpretation in theories and proof contexts has been
  3094 extended.  One may now specify (and prove) equations, which are
  3095 unfolded in interpreted theorems.  This is useful for replacing
  3096 defined concepts (constants depending on locale parameters) by
  3097 concepts already existing in the target context.  Example:
  3098 
  3099   interpretation partial_order ["op <= :: [int, int] => bool"]
  3100     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3101 
  3102 Typically, the constant `partial_order.less' is created by a
  3103 definition specification element in the context of locale
  3104 partial_order.
  3105 
  3106 * Method "induct": improved internal context management to support
  3107 local fixes and defines on-the-fly. Thus explicit meta-level
  3108 connectives !!  and ==> are rarely required anymore in inductive goals
  3109 (using object-logic connectives for this purpose has been long
  3110 obsolete anyway). Common proof patterns are explained in
  3111 src/HOL/Induct/Common_Patterns.thy, see also
  3112 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3113 examples.
  3114 
  3115 * Method "induct": improved handling of simultaneous goals. Instead of
  3116 introducing object-level conjunction, the statement is now split into
  3117 several conclusions, while the corresponding symbolic cases are nested
  3118 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3119 see src/HOL/Induct/Common_Patterns.thy, for example.
  3120 
  3121 * Method "induct": mutual induction rules are now specified as a list
  3122 of rule sharing the same induction cases. HOL packages usually provide
  3123 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3124 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3125 mutual induction rules differently, i.e. like this:
  3126 
  3127   (induct rule: foo_bar.inducts)
  3128   (induct set: foo bar)
  3129   (induct pred: foo bar)
  3130   (induct type: foo bar)
  3131 
  3132 The ML function ProjectRule.projections turns old-style rules into the
  3133 new format.
  3134 
  3135 * Method "coinduct": dual of induction, see
  3136 src/HOL/Library/Coinductive_List.thy for various examples.
  3137 
  3138 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3139 considered a legacy feature.
  3140 
  3141 * Attribute "symmetric" produces result with standardized schematic
  3142 variables (index 0).  Potential INCOMPATIBILITY.
  3143 
  3144 * Simplifier: by default the simplifier trace only shows top level
  3145 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3146 default. Thus there is less danger of being flooded by the trace. The
  3147 trace indicates where parts have been suppressed.
  3148   
  3149 * Provers/classical: removed obsolete classical version of elim_format
  3150 attribute; classical elim/dest rules are now treated uniformly when
  3151 manipulating the claset.
  3152 
  3153 * Provers/classical: stricter checks to ensure that supplied intro,
  3154 dest and elim rules are well-formed; dest and elim rules must have at
  3155 least one premise.
  3156 
  3157 * Provers/classical: attributes dest/elim/intro take an optional
  3158 weight argument for the rule (just as the Pure versions).  Weights are
  3159 ignored by automated tools, but determine the search order of single
  3160 rule steps.
  3161 
  3162 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3163 where the body does not mention the bound variable.  Note that dummy
  3164 patterns implicitly depend on their context of bounds, which makes
  3165 "{_. _}" match any set comprehension as expected.  Potential
  3166 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3167 constant "_idtdummy" in the binding position.
  3168 
  3169 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3170 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3171 for example "A -> B" => "Pi A (%_. B)".
  3172 
  3173 * Pure: 'class_deps' command visualizes the subclass relation, using
  3174 the graph browser tool.
  3175 
  3176 * Pure: 'print_theory' now suppresses certain internal declarations by
  3177 default; use '!' option for full details.
  3178 
  3179 
  3180 *** HOL ***
  3181 
  3182 * Method "metis" proves goals by applying the Metis general-purpose
  3183 resolution prover (see also http://gilith.com/software/metis/).
  3184 Examples are in the directory MetisExamples.  WARNING: the
  3185 Isabelle/HOL-Metis integration does not yet work properly with
  3186 multi-threading.
  3187   
  3188 * Command 'sledgehammer' invokes external automatic theorem provers as
  3189 background processes.  It generates calls to the "metis" method if
  3190 successful. These can be pasted into the proof.  Users do not have to
  3191 wait for the automatic provers to return.  WARNING: does not really
  3192 work with multi-threading.
  3193 
  3194 * New "auto_quickcheck" feature tests outermost goal statements for
  3195 potential counter-examples.  Controlled by ML references
  3196 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3197 5000 milliseconds).  Fails silently if statements is outside of
  3198 executable fragment, or any other codgenerator problem occurs.
  3199 
  3200 * New constant "undefined" with axiom "undefined x = undefined".
  3201 
  3202 * Added class "HOL.eq", allowing for code generation with polymorphic
  3203 equality.
  3204 
  3205 * Some renaming of class constants due to canonical name prefixing in
  3206 the new 'class' package:
  3207 
  3208     HOL.abs ~> HOL.abs_class.abs
  3209     HOL.divide ~> HOL.divide_class.divide
  3210     0 ~> HOL.zero_class.zero
  3211     1 ~> HOL.one_class.one
  3212     op + ~> HOL.plus_class.plus
  3213     op - ~> HOL.minus_class.minus
  3214     uminus ~> HOL.minus_class.uminus
  3215     op * ~> HOL.times_class.times
  3216     op < ~> HOL.ord_class.less
  3217     op <= > HOL.ord_class.less_eq
  3218     Nat.power ~> Power.power_class.power
  3219     Nat.size ~> Nat.size_class.size
  3220     Numeral.number_of ~> Numeral.number_class.number_of
  3221     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3222     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3223     Orderings.min ~> Orderings.ord_class.min
  3224     Orderings.max ~> Orderings.ord_class.max
  3225     Divides.op div ~> Divides.div_class.div
  3226     Divides.op mod ~> Divides.div_class.mod
  3227     Divides.op dvd ~> Divides.div_class.dvd
  3228 
  3229 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3230 
  3231 a) User-defined constants using any of the names "plus", "minus",
  3232 "times", "less" or "less_eq". The standard syntax translations for
  3233 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3234 names.
  3235 
  3236 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3237 INCOMPATIBILITY: use more specific names.
  3238 
  3239 c) Permutative equations (e.g. "a + b = b + a")
  3240 Since the change of names also changes the order of terms, permutative
  3241 rewrite rules may get applied in a different order. Experience shows
  3242 that this is rarely the case (only two adaptions in the whole Isabelle
  3243 distribution).  INCOMPATIBILITY: rewrite proofs
  3244 
  3245 d) ML code directly refering to constant names
  3246 This in general only affects hand-written proof tactics, simprocs and
  3247 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3248 Consider using @{const_name} antiquotation.
  3249 
  3250 * New class "default" with associated constant "default".
  3251 
  3252 * Function "sgn" is now overloaded and available on int, real, complex
  3253 (and other numeric types), using class "sgn".  Two possible defs of
  3254 sgn are given as equational assumptions in the classes sgn_if and
  3255 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3256 INCOMPATIBILITY.
  3257 
  3258 * Locale "partial_order" now unified with class "order" (cf. theory
  3259 Orderings), added parameter "less".  INCOMPATIBILITY.
  3260 
  3261 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3262 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3263 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3264 
  3265 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3266 changed order of proof goals in instance proofs.
  3267 
  3268 * The transitivity reasoner for partial and linear orders is set up
  3269 for classes "order" and "linorder".  Instances of the reasoner are available
  3270 in all contexts importing or interpreting the corresponding locales.
  3271 Method "order" invokes the reasoner separately; the reasoner
  3272 is also integrated with the Simplifier as a solver.  Diagnostic
  3273 command 'print_orders' shows the available instances of the reasoner
  3274 in the current context.
  3275 
  3276 * Localized monotonicity predicate in theory "Orderings"; integrated
  3277 lemmas max_of_mono and min_of_mono with this predicate.
  3278 INCOMPATIBILITY.
  3279 
  3280 * Formulation of theorem "dense" changed slightly due to integration
  3281 with new class dense_linear_order.
  3282 
  3283 * Uniform lattice theory development in HOL.
  3284 
  3285     constants "meet" and "join" now named "inf" and "sup"
  3286     constant "Meet" now named "Inf"
  3287 
  3288     classes "meet_semilorder" and "join_semilorder" now named
  3289       "lower_semilattice" and "upper_semilattice"
  3290     class "lorder" now named "lattice"
  3291     class "comp_lat" now named "complete_lattice"
  3292 
  3293     Instantiation of lattice classes allows explicit definitions
  3294     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3295 
  3296   INCOMPATIBILITY.  Theorem renames:
  3297 
  3298     meet_left_le            ~> inf_le1
  3299     meet_right_le           ~> inf_le2
  3300     join_left_le            ~> sup_ge1
  3301     join_right_le           ~> sup_ge2
  3302     meet_join_le            ~> inf_sup_ord
  3303     le_meetI                ~> le_infI
  3304     join_leI                ~> le_supI
  3305     le_meet                 ~> le_inf_iff
  3306     le_join                 ~> ge_sup_conv
  3307     meet_idempotent         ~> inf_idem
  3308     join_idempotent         ~> sup_idem
  3309     meet_comm               ~> inf_commute
  3310     join_comm               ~> sup_commute
  3311     meet_leI1               ~> le_infI1
  3312     meet_leI2               ~> le_infI2
  3313     le_joinI1               ~> le_supI1
  3314     le_joinI2               ~> le_supI2
  3315     meet_assoc              ~> inf_assoc
  3316     join_assoc              ~> sup_assoc
  3317     meet_left_comm          ~> inf_left_commute
  3318     meet_left_idempotent    ~> inf_left_idem
  3319     join_left_comm          ~> sup_left_commute
  3320     join_left_idempotent    ~> sup_left_idem
  3321     meet_aci                ~> inf_aci
  3322     join_aci                ~> sup_aci
  3323     le_def_meet             ~> le_iff_inf
  3324     le_def_join             ~> le_iff_sup
  3325     join_absorp2            ~> sup_absorb2
  3326     join_absorp1            ~> sup_absorb1
  3327     meet_absorp1            ~> inf_absorb1
  3328     meet_absorp2            ~> inf_absorb2
  3329     meet_join_absorp        ~> inf_sup_absorb
  3330     join_meet_absorp        ~> sup_inf_absorb
  3331     distrib_join_le         ~> distrib_sup_le
  3332     distrib_meet_le         ~> distrib_inf_le
  3333 
  3334     add_meet_distrib_left   ~> add_inf_distrib_left
  3335     add_join_distrib_left   ~> add_sup_distrib_left
  3336     is_join_neg_meet        ~> is_join_neg_inf
  3337     is_meet_neg_join        ~> is_meet_neg_sup
  3338     add_meet_distrib_right  ~> add_inf_distrib_right
  3339     add_join_distrib_right  ~> add_sup_distrib_right
  3340     add_meet_join_distribs  ~> add_sup_inf_distribs
  3341     join_eq_neg_meet        ~> sup_eq_neg_inf
  3342     meet_eq_neg_join        ~> inf_eq_neg_sup
  3343     add_eq_meet_join        ~> add_eq_inf_sup
  3344     meet_0_imp_0            ~> inf_0_imp_0
  3345     join_0_imp_0            ~> sup_0_imp_0
  3346     meet_0_eq_0             ~> inf_0_eq_0
  3347     join_0_eq_0             ~> sup_0_eq_0
  3348     neg_meet_eq_join        ~> neg_inf_eq_sup
  3349     neg_join_eq_meet        ~> neg_sup_eq_inf
  3350     join_eq_if              ~> sup_eq_if
  3351 
  3352     mono_meet               ~> mono_inf
  3353     mono_join               ~> mono_sup
  3354     meet_bool_eq            ~> inf_bool_eq
  3355     join_bool_eq            ~> sup_bool_eq
  3356     meet_fun_eq             ~> inf_fun_eq
  3357     join_fun_eq             ~> sup_fun_eq
  3358     meet_set_eq             ~> inf_set_eq
  3359     join_set_eq             ~> sup_set_eq
  3360     meet1_iff               ~> inf1_iff
  3361     meet2_iff               ~> inf2_iff
  3362     meet1I                  ~> inf1I
  3363     meet2I                  ~> inf2I
  3364     meet1D1                 ~> inf1D1
  3365     meet2D1                 ~> inf2D1
  3366     meet1D2                 ~> inf1D2
  3367     meet2D2                 ~> inf2D2
  3368     meet1E                  ~> inf1E
  3369     meet2E                  ~> inf2E
  3370     join1_iff               ~> sup1_iff
  3371     join2_iff               ~> sup2_iff
  3372     join1I1                 ~> sup1I1
  3373     join2I1                 ~> sup2I1
  3374     join1I1                 ~> sup1I1
  3375     join2I2                 ~> sup1I2
  3376     join1CI                 ~> sup1CI
  3377     join2CI                 ~> sup2CI
  3378     join1E                  ~> sup1E
  3379     join2E                  ~> sup2E
  3380 
  3381     is_meet_Meet            ~> is_meet_Inf
  3382     Meet_bool_def           ~> Inf_bool_def
  3383     Meet_fun_def            ~> Inf_fun_def
  3384     Meet_greatest           ~> Inf_greatest
  3385     Meet_lower              ~> Inf_lower
  3386     Meet_set_def            ~> Inf_set_def
  3387 
  3388     Sup_def                 ~> Sup_Inf
  3389     Sup_bool_eq             ~> Sup_bool_def
  3390     Sup_fun_eq              ~> Sup_fun_def
  3391     Sup_set_eq              ~> Sup_set_def
  3392 
  3393     listsp_meetI            ~> listsp_infI
  3394     listsp_meet_eq          ~> listsp_inf_eq
  3395 
  3396     meet_min                ~> inf_min
  3397     join_max                ~> sup_max
  3398 
  3399 * Added syntactic class "size"; overloaded constant "size" now has
  3400 type "'a::size ==> bool"
  3401 
  3402 * Internal reorganisation of `size' of datatypes: size theorems
  3403 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3404 simplification rules by default!); theorems "prod.size" now named
  3405 "*.size".
  3406 
  3407 * Class "div" now inherits from class "times" rather than "type".
  3408 INCOMPATIBILITY.
  3409 
  3410 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3411 Linorder etc.  have disappeared; operations defined in terms of
  3412 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3413 
  3414 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3415 
  3416 * HOL-Word: New extensive library and type for generic, fixed size
  3417 machine words, with arithemtic, bit-wise, shifting and rotating
  3418 operations, reflection into int, nat, and bool lists, automation for
  3419 linear arithmetic (by automatic reflection into nat or int), including
  3420 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3421 arithmetic type classes, supporting automatic simplification of
  3422 numerals on all operations.
  3423 
  3424 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3425 
  3426 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3427 
  3428 * Code generator library theories:
  3429   - Code_Integer represents HOL integers by big integer literals in target
  3430     languages.
  3431   - Code_Char represents HOL characters by character literals in target
  3432     languages.
  3433   - Code_Char_chr like Code_Char, but also offers treatment of character
  3434     codes; includes Code_Integer.
  3435   - Executable_Set allows to generate code for finite sets using lists.
  3436   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3437     denominator).
  3438   - Executable_Real implements a subset of real numbers, namly those
  3439     representable by rational numbers.
  3440   - Efficient_Nat implements natural numbers by integers, which in general will
  3441     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3442     includes Code_Integer.
  3443   - Code_Index provides an additional datatype index which is mapped to
  3444     target-language built-in integers.
  3445   - Code_Message provides an additional datatype message_string which is isomorphic to
  3446     strings; messages are mapped to target-language strings.
  3447 
  3448 * New package for inductive predicates
  3449 
  3450   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3451 
  3452     inductive
  3453       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3454       for z_1 :: U_1 and ... and z_n :: U_m
  3455     where
  3456       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3457     | ...
  3458 
  3459   with full support for type-inference, rather than
  3460 
  3461     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3462 
  3463     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3464     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3465 
  3466     inductive "s z_1 ... z_m"
  3467     intros
  3468       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3469       ...
  3470 
  3471   For backward compatibility, there is a wrapper allowing inductive
  3472   sets to be defined with the new package via
  3473 
  3474     inductive_set
  3475       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3476       for z_1 :: U_1 and ... and z_n :: U_m
  3477     where
  3478       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3479     | ...
  3480 
  3481   or
  3482 
  3483     inductive_set
  3484       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3485       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3486       for z_1 :: U_1 and ... and z_n :: U_m
  3487     where
  3488       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3489     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3490     | ...
  3491 
  3492   if the additional syntax "p ..." is required.
  3493 
  3494   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3495   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3496 
  3497   INCOMPATIBILITIES:
  3498 
  3499   - Since declaration and definition of inductive sets or predicates
  3500     is no longer separated, abbreviations involving the newly
  3501     introduced sets or predicates must be specified together with the
  3502     introduction rules after the 'where' keyword (see above), rather
  3503     than before the actual inductive definition.
  3504 
  3505   - The variables in induction and elimination rules are now
  3506     quantified in the order of their occurrence in the introduction
  3507     rules, rather than in alphabetical order. Since this may break
  3508     some proofs, these proofs either have to be repaired, e.g. by
  3509     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3510     statements of the form
  3511 
  3512       case (rule_i a_i_1 ... a_i_{k_i})
  3513 
  3514     or the old order of quantification has to be restored by explicitly adding
  3515     meta-level quantifiers in the introduction rules, i.e.
  3516 
  3517       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3518 
  3519   - The format of the elimination rules is now
  3520 
  3521       p z_1 ... z_m x_1 ... x_n ==>
  3522         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3523         ==> ... ==> P
  3524 
  3525     for predicates and
  3526 
  3527       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3528         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3529         ==> ... ==> P
  3530 
  3531     for sets rather than
  3532 
  3533       x : s z_1 ... z_m ==>
  3534         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3535         ==> ... ==> P
  3536 
  3537     This may require terms in goals to be expanded to n-tuples
  3538     (e.g. using case_tac or simplification with the split_paired_all
  3539     rule) before the above elimination rule is applicable.
  3540 
  3541   - The elimination or case analysis rules for (mutually) inductive
  3542     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3543     list of rules "p_1_..._p_k.elims" is no longer available.
  3544 
  3545 * New package "function"/"fun" for general recursive functions,
  3546 supporting mutual and nested recursion, definitions in local contexts,
  3547 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3548 for small examples, and the separate tutorial on the function
  3549 package. The old recdef "package" is still available as before, but
  3550 users are encouraged to use the new package.
  3551 
  3552 * Method "lexicographic_order" automatically synthesizes termination
  3553 relations as lexicographic combinations of size measures. 
  3554 
  3555 * Case-expressions allow arbitrary constructor-patterns (including
  3556 "_") and take their order into account, like in functional
  3557 programming.  Internally, this is translated into nested
  3558 case-expressions; missing cases are added and mapped to the predefined
  3559 constant "undefined". In complicated cases printing may no longer show
  3560 the original input but the internal form. Lambda-abstractions allow
  3561 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3562 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3563 variable.
  3564 
  3565 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3566 is an abbreviation for "of_nat :: nat => int". The simplification
  3567 rules for "of_nat" have been changed to work like "int" did
  3568 previously.  Potential INCOMPATIBILITY:
  3569   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3570   - of_nat_diff and of_nat_mult are no longer default simp rules
  3571 
  3572 * Method "algebra" solves polynomial equations over (semi)rings using
  3573 Groebner bases. The (semi)ring structure is defined by locales and the
  3574 tool setup depends on that generic context. Installing the method for
  3575 a specific type involves instantiating the locale and possibly adding
  3576 declarations for computation on the coefficients.  The method is
  3577 already instantiated for natural numbers and for the axiomatic class
  3578 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3579 CALCULEMUS 2007 for the general principles underlying this
  3580 architecture of context-aware proof-tools.
  3581 
  3582 * Method "ferrack" implements quantifier elimination over
  3583 special-purpose dense linear orders using locales (analogous to
  3584 "algebra"). The method is already installed for class
  3585 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3586 rat, etc.
  3587 
  3588 * Former constant "List.op @" now named "List.append".  Use ML
  3589 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3590 circumvent possible incompatibilities when working on ML level.
  3591 
  3592 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3593 
  3594 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3595 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3596 
  3597 * New syntax for Haskell-like list comprehension (input only), eg.
  3598 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3599 
  3600 * The special syntax for function "filter" has changed from [x :
  3601 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3602 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3603 
  3604 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3605 defined on nat only, as an abbreviation for [a..<Suc b]
  3606 INCOMPATIBILITY.
  3607 
  3608 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3609 
  3610 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3611 
  3612 * New lemma collection field_simps (an extension of ring_simps) for
  3613 manipulating (in)equations involving division. Multiplies with all
  3614 denominators that can be proved to be non-zero (in equations) or
  3615 positive/negative (in inequations).
  3616 
  3617 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3618 have been improved and renamed to ring_simps, group_simps and
  3619 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3620 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3621 
  3622 * Theory Library/Commutative_Ring: switched from recdef to function
  3623 package; constants add, mul, pow now curried.  Infix syntax for
  3624 algebraic operations.
  3625 
  3626 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3627 INCOMPATIBILITY.
  3628 
  3629 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3630 INCOMPATIBILITY.
  3631 
  3632 * HOL/records: generalised field-update to take a function on the
  3633 field rather than the new value: r(|A := x|) is translated to A_update
  3634 (K x) r The K-combinator that is internally used is called K_record.
  3635 INCOMPATIBILITY: Usage of the plain update functions has to be
  3636 adapted.
  3637  
  3638 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3639 * x = 0, which are required for a semiring.  Richer structures do not
  3640 inherit from semiring_0 anymore, because this property is a theorem
  3641 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3642 there is more to prove, but this is mostly trivial.
  3643 
  3644 * Class "recpower" is generalized to arbitrary monoids, not just
  3645 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3646 commutativity or semiring properties additionally.
  3647 
  3648 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3649 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3650 better use 'abbreviation'.
  3651 
  3652 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3653 
  3654 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3655 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3656 significant changes for setting up numeral syntax for types:
  3657   - New constants Numeral.pred and Numeral.succ instead
  3658       of former Numeral.bin_pred and Numeral.bin_succ.
  3659   - Use integer operations instead of bin_add, bin_mult and so on.
  3660   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3661   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3662 
  3663 See src/HOL/Integ/IntArith.thy for an example setup.
  3664 
  3665 * Command 'normal_form' computes the normal form of a term that may
  3666 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3667 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3668 heavy-duty computations because the functions are compiled to ML
  3669 first.  Correspondingly, a method "normalization" is provided.  See
  3670 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3671 
  3672 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3673 25 like -->); output depends on the "iff" print_mode, the default is
  3674 "A = B" (with priority 50).
  3675 
  3676 * Relations less (<) and less_eq (<=) are also available on type bool.
  3677 Modified syntax to disallow nesting without explicit parentheses,
  3678 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3679 INCOMPATIBILITY.
  3680 
  3681 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3682 
  3683 * Relation composition operator "op O" now has precedence 75 and binds
  3684 stronger than union and intersection. INCOMPATIBILITY.
  3685 
  3686 * The old set interval syntax "{m..n(}" (and relatives) has been
  3687 removed.  Use "{m..<n}" (and relatives) instead.
  3688 
  3689 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3690 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3691 ``declare [[simproc del: neq]]''.
  3692 
  3693 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3694 True/False.
  3695 
  3696 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3697 
  3698 * Theorem setsum_mult renamed to setsum_right_distrib.
  3699 
  3700 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3701 ``rule'' method.
  3702 
  3703 * Reimplemented methods "sat" and "satx", with several improvements:
  3704 goals no longer need to be stated as "<prems> ==> False", equivalences
  3705 (i.e. "=" on type bool) are handled, variable names of the form
  3706 "lit_<n>" are no longer reserved, significant speedup.
  3707 
  3708 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3709 zChaff is still supported as well.
  3710 
  3711 * 'inductive' and 'datatype': provide projections of mutual rules,
  3712 bundled as foo_bar.inducts;
  3713 
  3714 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3715 Library.
  3716 
  3717 * Library: moved theory Accessible_Part to main HOL.
  3718 
  3719 * Library: added theory Coinductive_List of potentially infinite lists
  3720 as greatest fixed-point.
  3721 
  3722 * Library: added theory AssocList which implements (finite) maps as
  3723 association lists.
  3724 
  3725 * Method "evaluation" solves goals (i.e. a boolean expression)
  3726 efficiently by compiling it to ML.  The goal is "proved" (via an
  3727 oracle) if it evaluates to True.
  3728 
  3729 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3730 also when invoked by the simplifier.  This results in the Simplifier
  3731 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3732 Configuration option fast_arith_split_limit=0 recovers the old
  3733 behavior.
  3734 
  3735 * Support for hex (0x20) and binary (0b1001) numerals.
  3736 
  3737 * New method: reify eqs (t), where eqs are equations for an
  3738 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3739 parameter, computes a term s::'b and a list xs::'a list and proves the
  3740 theorem I xs s = t. This is also known as reification or quoting. The
  3741 resulting theorem is applied to the subgoal to substitute t with I xs
  3742 s.  If t is omitted, the subgoal itself is reified.
  3743 
  3744 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3745 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3746 where f is supposed to be a computable function (in the sense of code
  3747 generattion). The method uses reify to compute s and xs as above then
  3748 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3749 r and finally gets the theorem t = r, which is again applied to the
  3750 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3751 
  3752 * Reflection: Automatic reification now handels binding, an example is
  3753 available in src/HOL/ex/ReflectionEx.thy
  3754 
  3755 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3756 command 'statespace' that is similar to 'record', but introduces an
  3757 abstract specification based on the locale infrastructure instead of
  3758 HOL types.  This leads to extra flexibility in composing state spaces,
  3759 in particular multiple inheritance and renaming of components.
  3760 
  3761 
  3762 *** HOL-Complex ***
  3763 
  3764 * Hyperreal: Functions root and sqrt are now defined on negative real
  3765 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3766 Nonnegativity side conditions have been removed from many lemmas, so
  3767 that more subgoals may now be solved by simplification; potential
  3768 INCOMPATIBILITY.
  3769 
  3770 * Real: new type classes formalize real normed vector spaces and
  3771 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3772 and norm :: 'a => real.
  3773 
  3774 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3775 reals into other types. The overloaded constant Reals :: 'a set is now
  3776 defined as range of_real; potential INCOMPATIBILITY.
  3777 
  3778 * Real: proper support for ML code generation, including 'quickcheck'.
  3779 Reals are implemented as arbitrary precision rationals.
  3780 
  3781 * Hyperreal: Several constants that previously worked only for the
  3782 reals have been generalized, so they now work over arbitrary vector
  3783 spaces. Type annotations may need to be added in some cases; potential
  3784 INCOMPATIBILITY.
  3785 
  3786   Infinitesimal  :: ('a::real_normed_vector) star set
  3787   HFinite        :: ('a::real_normed_vector) star set
  3788   HInfinite      :: ('a::real_normed_vector) star set
  3789   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3790   monad          :: ('a::real_normed_vector) star => 'a star set
  3791   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3792   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3793   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3794   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3795   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3796   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3797   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3798   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3799   sgn            :: 'a::real_normed_vector => 'a
  3800   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3801 
  3802 * Complex: Some complex-specific constants are now abbreviations for
  3803 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3804 hnorm.  Other constants have been entirely removed in favor of the
  3805 polymorphic versions (INCOMPATIBILITY):
  3806 
  3807   approx        <-- capprox
  3808   HFinite       <-- CFinite
  3809   HInfinite     <-- CInfinite
  3810   Infinitesimal <-- CInfinitesimal
  3811   monad         <-- cmonad
  3812   galaxy        <-- cgalaxy
  3813   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3814   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3815   (ns)deriv     <-- (ns)cderiv
  3816 
  3817 
  3818 *** HOL-Algebra ***
  3819 
  3820 * Formalisation of ideals and the quotient construction over rings.
  3821 
  3822 * Order and lattice theory no longer based on records.
  3823 INCOMPATIBILITY.
  3824 
  3825 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3826 greatest_closed.  INCOMPATIBILITY.
  3827 
  3828 * Method algebra is now set up via an attribute.  For examples see
  3829 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3830 of algebraic structures.
  3831 
  3832 * Renamed theory CRing to Ring.
  3833 
  3834 
  3835 *** HOL-Nominal ***
  3836 
  3837 * Substantial, yet incomplete support for nominal datatypes (binding
  3838 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3839 src/HOL/Nominal/Examples.  Prospective users should consult
  3840 http://isabelle.in.tum.de/nominal/
  3841 
  3842 
  3843 *** ML ***
  3844 
  3845 * ML basics: just one true type int, which coincides with IntInf.int
  3846 (even on SML/NJ).
  3847 
  3848 * ML within Isar: antiquotations allow to embed statically-checked
  3849 formal entities in the source, referring to the context available at
  3850 compile-time.  For example:
  3851 
  3852 ML {* @{sort "{zero,one}"} *}
  3853 ML {* @{typ "'a => 'b"} *}
  3854 ML {* @{term "%x. x"} *}
  3855 ML {* @{prop "x == y"} *}
  3856 ML {* @{ctyp "'a => 'b"} *}
  3857 ML {* @{cterm "%x. x"} *}
  3858 ML {* @{cprop "x == y"} *}
  3859 ML {* @{thm asm_rl} *}
  3860 ML {* @{thms asm_rl} *}
  3861 ML {* @{type_name c} *}
  3862 ML {* @{type_syntax c} *}
  3863 ML {* @{const_name c} *}
  3864 ML {* @{const_syntax c} *}
  3865 ML {* @{context} *}
  3866 ML {* @{theory} *}
  3867 ML {* @{theory Pure} *}
  3868 ML {* @{theory_ref} *}
  3869 ML {* @{theory_ref Pure} *}
  3870 ML {* @{simpset} *}
  3871 ML {* @{claset} *}
  3872 ML {* @{clasimpset} *}
  3873 
  3874 The same works for sources being ``used'' within an Isar context.
  3875 
  3876 * ML in Isar: improved error reporting; extra verbosity with
  3877 ML_Context.trace enabled.
  3878 
  3879 * Pure/General/table.ML: the join operations now works via exceptions
  3880 DUP/SAME instead of type option. This is simpler in simple cases, and
  3881 admits slightly more efficient complex applications.
  3882 
  3883 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3884 use Context.generic instead of just theory.
  3885 
  3886 * Pure: datatype Context.generic joins theory/Proof.context and
  3887 provides some facilities for code that works in either kind of
  3888 context, notably GenericDataFun for uniform theory and proof data.
  3889 
  3890 * Pure: simplified internal attribute type, which is now always
  3891 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3892 local (Proof.context) attributes have been discontinued, while
  3893 minimizing code duplication. Thm.rule_attribute and
  3894 Thm.declaration_attribute build canonical attributes; see also structure
  3895 Context for further operations on Context.generic, notably
  3896 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3897 declarations and definitions.
  3898 
  3899 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3900 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3901 init only required for impure data. INCOMPATIBILITY: empty really need
  3902 to be empty (no dependencies on theory content!)
  3903 
  3904 * Pure/kernel: consts certification ignores sort constraints given in
  3905 signature declarations. (This information is not relevant to the
  3906 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3907 potential INCOMPATIBILITY.
  3908 
  3909 * Pure: axiomatic type classes are now purely definitional, with
  3910 explicit proofs of class axioms and super class relations performed
  3911 internally. See Pure/axclass.ML for the main internal interfaces --
  3912 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3913 AxClass.axiomatize_class/classrel/arity supersede
  3914 Sign.add_classes/classrel/arities.
  3915 
  3916 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3917 global/local versions on theory vs. Proof.context have been
  3918 discontinued; Attrib.syntax and Method.syntax have been adapted
  3919 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3920 attributes, methods, etc.
  3921 
  3922 * Pure: several functions of signature "... -> theory -> theory * ..."
  3923 have been reoriented to "... -> theory -> ... * theory" in order to
  3924 allow natural usage in combination with the ||>, ||>>, |-> and
  3925 fold_map combinators.
  3926 
  3927 * Pure: official theorem names (closed derivations) and additional
  3928 comments (tags) are now strictly separate.  Name hints -- which are
  3929 maintained as tags -- may be attached any time without affecting the
  3930 derivation.
  3931 
  3932 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3933 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3934 achieve the old behaviour.
  3935 
  3936 * Pure: the "Goal" constant is now called "prop", supporting a
  3937 slightly more general idea of ``protecting'' meta-level rule
  3938 statements.
  3939 
  3940 * Pure: Logic.(un)varify only works in a global context, which is now
  3941 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3942 Logic.legacy_(un)varify as temporary workaround.
  3943 
  3944 * Pure: structure Name provides scalable operations for generating
  3945 internal variable names, notably Name.variants etc.  This replaces
  3946 some popular functions from term.ML:
  3947 
  3948   Term.variant		->  Name.variant
  3949   Term.variantlist	->  Name.variant_list
  3950   Term.invent_names	->  Name.invent_list
  3951 
  3952 Note that low-level renaming rarely occurs in new code -- operations
  3953 from structure Variable are used instead (see below).
  3954 
  3955 * Pure: structure Variable provides fundamental operations for proper
  3956 treatment of fixed/schematic variables in a context.  For example,
  3957 Variable.import introduces fixes for schematics of given facts and
  3958 Variable.export reverses the effect (up to renaming) -- this replaces
  3959 various freeze_thaw operations.
  3960 
  3961 * Pure: structure Goal provides simple interfaces for
  3962 init/conclude/finish and tactical prove operations (replacing former
  3963 Tactic.prove).  Goal.prove is the canonical way to prove results
  3964 within a given context; Goal.prove_global is a degraded version for
  3965 theory level goals, including a global Drule.standard.  Note that
  3966 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3967 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3968 in a locale context).
  3969 
  3970 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3971 and type checking (Syntax.check_term etc.), with common combinations
  3972 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3973 which are considered legacy and await removal.
  3974 
  3975 * Pure/Syntax: generic interfaces for type unchecking
  3976 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3977 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3978 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3979 available for convenience, but refer to the very same operations using
  3980 a mere theory instead of a full context.
  3981 
  3982 * Isar: simplified treatment of user-level errors, using exception
  3983 ERROR of string uniformly.  Function error now merely raises ERROR,
  3984 without any side effect on output channels.  The Isar toplevel takes
  3985 care of proper display of ERROR exceptions.  ML code may use plain
  3986 handle/can/try; cat_error may be used to concatenate errors like this:
  3987 
  3988   ... handle ERROR msg => cat_error msg "..."
  3989 
  3990 Toplevel ML code (run directly or through the Isar toplevel) may be
  3991 embedded into the Isar toplevel with exception display/debug like
  3992 this:
  3993 
  3994   Isar.toplevel (fn () => ...)
  3995 
  3996 INCOMPATIBILITY, removed special transform_error facilities, removed
  3997 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3998 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3999 -- use plain ERROR instead.
  4000 
  4001 * Isar: theory setup now has type (theory -> theory), instead of a
  4002 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4003 
  4004 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4005 ProofContext.debug/verbose flags.
  4006 
  4007 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4008 theory before entering a proof state.  Transactions now always see a
  4009 quasi-functional intermediate checkpoint, both in interactive and
  4010 batch mode.
  4011 
  4012 * Isar: simplified interfaces for outer syntax.  Renamed
  4013 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4014 OuterSyntax.add_parsers -- this functionality is now included in
  4015 OuterSyntax.command etc.  INCOMPATIBILITY.
  4016 
  4017 * Simplifier: the simpset of a running simplification process now
  4018 contains a proof context (cf. Simplifier.the_context), which is the
  4019 very context that the initial simpset has been retrieved from (by
  4020 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4021 (solver, looper etc.) may depend on arbitrary proof data.
  4022 
  4023 * Simplifier.inherit_context inherits the proof context (plus the
  4024 local bounds) of the current simplification process; any simproc
  4025 etc. that calls the Simplifier recursively should do this!  Removed
  4026 former Simplifier.inherit_bounds, which is already included here --
  4027 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4028 specify an explicit context using Simplifier.context/theory_context.
  4029 
  4030 * Simplifier/Classical Reasoner: more abstract interfaces
  4031 change_simpset/claset for modifying the simpset/claset reference of a
  4032 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4033 INCOMPATIBILITY.
  4034 
  4035 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4036 "Trueprop" etc.
  4037 
  4038 
  4039 *** System ***
  4040 
  4041 * settings: the default heap location within ISABELLE_HOME_USER now
  4042 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4043 Isabelle installations.
  4044 
  4045 * isabelle-process: option -S (secure mode) disables some critical
  4046 operations, notably runtime compilation and evaluation of ML source
  4047 code.
  4048 
  4049 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4050 
  4051 * Support for parallel execution, using native multicore support of
  4052 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4053 independent theories, according to the given theory header
  4054 specifications. The maximum number of worker threads is specified via
  4055 usedir option -M or the "max-threads" setting in Proof General. A
  4056 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4057 to 6 on a 8-core machine.  User-code needs to observe certain
  4058 guidelines for thread-safe programming, see appendix A in the Isar
  4059 Implementation manual.
  4060 
  4061 
  4062 
  4063 New in Isabelle2005 (October 2005)
  4064 ----------------------------------
  4065 
  4066 *** General ***
  4067 
  4068 * Theory headers: the new header syntax for Isar theories is
  4069 
  4070   theory <name>
  4071   imports <theory1> ... <theoryN>
  4072   uses <file1> ... <fileM>
  4073   begin
  4074 
  4075 where the 'uses' part is optional.  The previous syntax
  4076 
  4077   theory <name> = <theory1> + ... + <theoryN>:
  4078 
  4079 will disappear in the next release.  Use isatool fixheaders to convert
  4080 existing theory files.  Note that there is no change in ancient
  4081 non-Isar theories now, but these will disappear soon.
  4082 
  4083 * Theory loader: parent theories can now also be referred to via
  4084 relative and absolute paths.
  4085 
  4086 * Command 'find_theorems' searches for a list of criteria instead of a
  4087 list of constants. Known criteria are: intro, elim, dest, name:string,
  4088 simp:term, and any term. Criteria can be preceded by '-' to select
  4089 theorems that do not match. Intro, elim, dest select theorems that
  4090 match the current goal, name:s selects theorems whose fully qualified
  4091 name contain s, and simp:term selects all simplification rules whose
  4092 lhs match term.  Any other term is interpreted as pattern and selects
  4093 all theorems matching the pattern. Available in ProofGeneral under
  4094 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4095 
  4096   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4097 
  4098 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4099 matching the current goal as introduction rule and not having "HOL."
  4100 in their name (i.e. not being defined in theory HOL).
  4101 
  4102 * Command 'thms_containing' has been discontinued in favour of
  4103 'find_theorems'; INCOMPATIBILITY.
  4104 
  4105 * Communication with Proof General is now 8bit clean, which means that
  4106 Unicode text in UTF-8 encoding may be used within theory texts (both
  4107 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4108 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4109 
  4110   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4111   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4112 
  4113 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4114 Classical Reasoner.  Typical big applications run around 2 times
  4115 faster.
  4116 
  4117 
  4118 *** Document preparation ***
  4119 
  4120 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4121 of raw sources.  Only those symbols that do not require additional
  4122 LaTeX packages (depending on comments in isabellesym.sty) are
  4123 displayed properly, everything else is left verbatim.  isatool display
  4124 and isatool print are used as front ends (these are subject to the
  4125 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4126 
  4127 * Command tags control specific markup of certain regions of text,
  4128 notably folding and hiding.  Predefined tags include "theory" (for
  4129 theory begin and end), "proof" for proof commands, and "ML" for
  4130 commands involving ML code; the additional tags "visible" and
  4131 "invisible" are unused by default.  Users may give explicit tag
  4132 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4133 interpretation of tags is determined by the LaTeX job during document
  4134 preparation: see option -V of isatool usedir, or options -n and -t of
  4135 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4136 \isadroptag.
  4137 
  4138 Several document versions may be produced at the same time via isatool
  4139 usedir (the generated index.html will link all of them).  Typical
  4140 specifications include ''-V document=theory,proof,ML'' to present
  4141 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4142 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4143 these parts without any formal replacement text.  The Isabelle site
  4144 default settings produce ''document'' and ''outline'' versions as
  4145 specified above.
  4146 
  4147 * Several new antiquotations:
  4148 
  4149   @{term_type term} prints a term with its type annotated;
  4150 
  4151   @{typeof term} prints the type of a term;
  4152 
  4153   @{const const} is the same as @{term const}, but checks that the
  4154   argument is a known logical constant;
  4155 
  4156   @{term_style style term} and @{thm_style style thm} print a term or
  4157   theorem applying a "style" to it
  4158 
  4159   @{ML text}
  4160 
  4161 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4162 definitions, equations, inequations etc., 'concl' printing only the
  4163 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4164 to print the specified premise.  TermStyle.add_style provides an ML
  4165 interface for introducing further styles.  See also the "LaTeX Sugar"
  4166 document practical applications.  The ML antiquotation prints
  4167 type-checked ML expressions verbatim.
  4168 
  4169 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4170 and 'text' support optional locale specification '(in loc)', which
  4171 specifies the default context for interpreting antiquotations.  For
  4172 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4173 
  4174 * Option 'locale=NAME' of antiquotations specifies an alternative
  4175 context interpreting the subsequent argument.  For example: @{thm
  4176 [locale=lattice] inf_assoc}.
  4177 
  4178 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4179 a proof context.
  4180 
  4181 * Proper output of antiquotations for theory commands involving a
  4182 proof context (such as 'locale' or 'theorem (in loc) ...').
  4183 
  4184 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4185 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4186 
  4187 * isatool usedir: new option -C (default true) controls whether option
  4188 -D should include a copy of the original document directory; -C false
  4189 prevents unwanted effects such as copying of administrative CVS data.
  4190 
  4191 
  4192 *** Pure ***
  4193 
  4194 * Considerably improved version of 'constdefs' command.  Now performs
  4195 automatic type-inference of declared constants; additional support for
  4196 local structure declarations (cf. locales and HOL records), see also
  4197 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4198 sequential dependencies of definitions within a single 'constdefs'
  4199 section; moreover, the declared name needs to be an identifier.  If
  4200 all fails, consider to fall back on 'consts' and 'defs' separately.
  4201 
  4202 * Improved indexed syntax and implicit structures.  First of all,
  4203 indexed syntax provides a notational device for subscripted
  4204 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4205 expressions.  Secondly, in a local context with structure
  4206 declarations, number indexes \<^sub>n or the empty index (default
  4207 number 1) refer to a certain fixed variable implicitly; option
  4208 show_structs controls printing of implicit structures.  Typical
  4209 applications of these concepts involve record types and locales.
  4210 
  4211 * New command 'no_syntax' removes grammar declarations (and
  4212 translations) resulting from the given syntax specification, which is
  4213 interpreted in the same manner as for the 'syntax' command.
  4214 
  4215 * 'Advanced' translation functions (parse_translation etc.) may depend
  4216 on the signature of the theory context being presently used for
  4217 parsing/printing, see also isar-ref manual.
  4218 
  4219 * Improved 'oracle' command provides a type-safe interface to turn an
  4220 ML expression of type theory -> T -> term into a primitive rule of
  4221 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4222 is already included here); see also FOL/ex/IffExample.thy;
  4223 INCOMPATIBILITY.
  4224 
  4225 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4226 before); "cI" is no longer bound, use "c.intro" instead.
  4227 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4228 axclasses vs. locales.
  4229 
  4230 * Improved internal renaming of symbolic identifiers -- attach primes
  4231 instead of base 26 numbers.
  4232 
  4233 * New flag show_question_marks controls printing of leading question
  4234 marks in schematic variable names.
  4235 
  4236 * In schematic variable names, *any* symbol following \<^isub> or
  4237 \<^isup> is now treated as part of the base name.  For example, the
  4238 following works without printing of awkward ".0" indexes:
  4239 
  4240   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4241     by simp
  4242 
  4243 * Inner syntax includes (*(*nested*) comments*).
  4244 
  4245 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4246 annotations as "(00...)".
  4247 
  4248 * Clear separation of logical types and nonterminals, where the latter
  4249 may only occur in 'syntax' specifications or type abbreviations.
  4250 Before that distinction was only partially implemented via type class
  4251 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4252 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4253 exotic syntax specifications may require further adaption
  4254 (e.g. Cube/Cube.thy).
  4255 
  4256 * Removed obsolete type class "logic", use the top sort {} instead.
  4257 Note that non-logical types should be declared as 'nonterminals'
  4258 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4259 specifications.
  4260 
  4261 * Attributes 'induct' and 'cases': type or set names may now be
  4262 locally fixed variables as well.
  4263 
  4264 * Simplifier: can now control the depth to which conditional rewriting
  4265 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4266 Limit.
  4267 
  4268 * Simplifier: simplification procedures may now take the current
  4269 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4270 interface), which is very useful for calling the Simplifier
  4271 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4272 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4273 low-level mk_simproc no longer applies Logic.varify internally, to
  4274 allow for use in a context of fixed variables.
  4275 
  4276 * thin_tac now works even if the assumption being deleted contains !!
  4277 or ==>.  More generally, erule now works even if the major premise of
  4278 the elimination rule contains !! or ==>.
  4279 
  4280 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4281 
  4282 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4283 from Pure, which contains all common declarations already.  Both
  4284 theories are defined via plain Isabelle/Isar .thy files.
  4285 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4286 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4287 use isatool fixcpure to adapt your theory and ML sources.
  4288 
  4289 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4290 selections of theorems in named facts via index ranges.
  4291 
  4292 * 'print_theorems': in theory mode, really print the difference
  4293 wrt. the last state (works for interactive theory development only),
  4294 in proof mode print all local facts (cf. 'print_facts');
  4295 
  4296 * 'hide': option '(open)' hides only base names.
  4297 
  4298 * More efficient treatment of intermediate checkpoints in interactive
  4299 theory development.
  4300 
  4301 * Code generator is now invoked via code_module (incremental code
  4302 generation) and code_library (modular code generation, ML structures
  4303 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4304 must be quoted when used as identifiers.
  4305 
  4306 * New 'value' command for reading, evaluating and printing terms using
  4307 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4308 quoted when used as identifier.
  4309 
  4310 
  4311 *** Locales ***
  4312 
  4313 * New commands for the interpretation of locale expressions in
  4314 theories (1), locales (2) and proof contexts (3).  These generate
  4315 proof obligations from the expression specification.  After the
  4316 obligations have been discharged, theorems of the expression are added
  4317 to the theory, target locale or proof context.  The synopsis of the
  4318 commands is a follows:
  4319 
  4320   (1) interpretation expr inst
  4321   (2) interpretation target < expr
  4322   (3) interpret expr inst
  4323 
  4324 Interpretation in theories and proof contexts require a parameter
  4325 instantiation of terms from the current context.  This is applied to
  4326 specifications and theorems of the interpreted expression.
  4327 Interpretation in locales only permits parameter renaming through the
  4328 locale expression.  Interpretation is smart in that interpretations
  4329 that are active already do not occur in proof obligations, neither are
  4330 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4331 inspect active interpretations of a particular locale.  For details,
  4332 see the Isar Reference manual.  Examples can be found in
  4333 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4334 
  4335 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4336 'interpret' instead.
  4337 
  4338 * New context element 'constrains' for adding type constraints to
  4339 parameters.
  4340 
  4341 * Context expressions: renaming of parameters with syntax
  4342 redeclaration.
  4343 
  4344 * Locale declaration: 'includes' disallowed.
  4345 
  4346 * Proper static binding of attribute syntax -- i.e. types / terms /
  4347 facts mentioned as arguments are always those of the locale definition
  4348 context, independently of the context of later invocations.  Moreover,
  4349 locale operations (renaming and type / term instantiation) are applied
  4350 to attribute arguments as expected.
  4351 
  4352 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4353 actual attributes; rare situations may require Attrib.attribute to
  4354 embed those attributes into Attrib.src that lack concrete syntax.
  4355 Attribute implementations need to cooperate properly with the static
  4356 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4357 Attrib.XXX_thm etc. already do the right thing without further
  4358 intervention.  Only unusual applications -- such as "where" or "of"
  4359 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4360 on the context and the facts involved -- may have to assign parsed
  4361 values to argument tokens explicitly.
  4362 
  4363 * Changed parameter management in theorem generation for long goal
  4364 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4365 theorem statement in rare situations.
  4366 
  4367 * Locale inspection command 'print_locale' omits notes elements.  Use
  4368 'print_locale!' to have them included in the output.
  4369 
  4370 
  4371 *** Provers ***
  4372 
  4373 * Provers/hypsubst.ML: improved version of the subst method, for
  4374 single-step rewriting: it now works in bound variable contexts. New is
  4375 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4376 rewrite a different subterm than the original subst method, which is
  4377 still available as 'simplesubst'.
  4378 
  4379 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4380 and quasi orders.
  4381 
  4382 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4383 reflexive-transitive closure of relations.
  4384 
  4385 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4386 limit (previously hard-coded with a value of 20) user-definable.
  4387 
  4388 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4389 is peformed already.  Object-logics merely need to finish their
  4390 initial simpset configuration as before.  INCOMPATIBILITY.
  4391 
  4392 
  4393 *** HOL ***
  4394 
  4395 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4396 
  4397   syntax (epsilon)
  4398     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4399 
  4400 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4401 and x-symbol; use option '-m epsilon' to get it actually printed.
  4402 Moreover, the mathematically important symbolic identifier \<epsilon>
  4403 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4404 
  4405 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4406 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4407 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4408 support corresponding Isar calculations.
  4409 
  4410 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4411 instead of ":".
  4412 
  4413 * theory SetInterval: changed the syntax for open intervals:
  4414 
  4415   Old       New
  4416   {..n(}    {..<n}
  4417   {)n..}    {n<..}
  4418   {m..n(}   {m..<n}
  4419   {)m..n}   {m<..n}
  4420   {)m..n(}  {m<..<n}
  4421 
  4422 The old syntax is still supported but will disappear in the next
  4423 release.  For conversion use the following Emacs search and replace
  4424 patterns (these are not perfect but work quite well):
  4425 
  4426   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4427   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4428 
  4429 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4430 equalities in commutative rings; method 'algebra' provides a generic
  4431 interface.
  4432 
  4433 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4434 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4435 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4436 be a tuple pattern.
  4437 
  4438 Some new syntax forms are available:
  4439 
  4440   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4441   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4442   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4443   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4444 
  4445 The latter form "\<Sum>x < k. e" used to be based on a separate
  4446 function "Summation", which has been discontinued.
  4447 
  4448 * theory Finite_Set: in structured induction proofs, the insert case
  4449 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4450 (insert F x)'.
  4451 
  4452 * The 'refute' command has been extended to support a much larger
  4453 fragment of HOL, including axiomatic type classes, constdefs and
  4454 typedefs, inductive datatypes and recursion.
  4455 
  4456 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4457 Requires zChaff with proof generation to be installed.  See
  4458 HOL/ex/SAT_Examples.thy for examples.
  4459 
  4460 * Datatype induction via method 'induct' now preserves the name of the
  4461 induction variable. For example, when proving P(xs::'a list) by
  4462 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4463 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4464 in unstructured proof scripts.
  4465 
  4466 * Reworked implementation of records.  Improved scalability for
  4467 records with many fields, avoiding performance problems for type
  4468 inference. Records are no longer composed of nested field types, but
  4469 of nested extension types. Therefore the record type only grows linear
  4470 in the number of extensions and not in the number of fields.  The
  4471 top-level (users) view on records is preserved.  Potential
  4472 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4473 old record representation. The type generated for a record is called
  4474 <record_name>_ext_type.
  4475 
  4476 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4477 proofs triggered by a record definition or a simproc (if
  4478 quick_and_dirty is enabled).  Definitions of large records can take
  4479 quite long.
  4480 
  4481 New simproc record_upd_simproc for simplification of multiple record
  4482 updates enabled by default.  Moreover, trivial updates are also
  4483 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4484 occasionally, since simplification is more powerful by default.
  4485 
  4486 * typedef: proper support for polymorphic sets, which contain extra
  4487 type-variables in the term.
  4488 
  4489 * Simplifier: automatically reasons about transitivity chains
  4490 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4491 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4492 old proofs break occasionally as simplification may now solve more
  4493 goals than previously.
  4494 
  4495 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4496 present.  Works for all partial orders (class "order"), in particular
  4497 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4498 just like y <= x.
  4499 
  4500 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4501 bound variable or a constant then the let is unfolded.  Otherwise
  4502 first a is simplified to b, and then f b is simplified to g. If
  4503 possible we abstract b from g arriving at "let x = b in h x",
  4504 otherwise we unfold the let and arrive at g.  The simproc can be
  4505 enabled/disabled by the reference use_let_simproc.  Potential
  4506 INCOMPATIBILITY since simplification is more powerful by default.
  4507 
  4508 * Classical reasoning: the meson method now accepts theorems as arguments.
  4509 
  4510 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4511 jobs to provide advice on the provability of subgoals.
  4512 
  4513 * Theory OrderedGroup and Ring_and_Field: various additions and
  4514 improvements to faciliate calculations involving equalities and
  4515 inequalities.
  4516 
  4517 The following theorems have been eliminated or modified
  4518 (INCOMPATIBILITY):
  4519 
  4520   abs_eq             now named abs_of_nonneg
  4521   abs_of_ge_0        now named abs_of_nonneg
  4522   abs_minus_eq       now named abs_of_nonpos
  4523   imp_abs_id         now named abs_of_nonneg
  4524   imp_abs_neg_id     now named abs_of_nonpos
  4525   mult_pos           now named mult_pos_pos
  4526   mult_pos_le        now named mult_nonneg_nonneg
  4527   mult_pos_neg_le    now named mult_nonneg_nonpos
  4528   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4529   mult_neg           now named mult_neg_neg
  4530   mult_neg_le        now named mult_nonpos_nonpos
  4531 
  4532 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4533      
  4534      zero_le_square
  4535      not_square_less_zero 
  4536 
  4537   The following lemmas have been deleted from Real/RealPow:
  4538   
  4539      realpow_zero_zero
  4540      realpow_two
  4541      realpow_less
  4542      zero_le_power
  4543      realpow_two_le
  4544      abs_realpow_two
  4545      realpow_two_abs     
  4546 
  4547 * Theory Parity: added rules for simplifying exponents.
  4548 
  4549 * Theory List:
  4550 
  4551 The following theorems have been eliminated or modified
  4552 (INCOMPATIBILITY):
  4553 
  4554   list_all_Nil       now named list_all.simps(1)
  4555   list_all_Cons      now named list_all.simps(2)
  4556   list_all_conv      now named list_all_iff
  4557   set_mem_eq         now named mem_iff
  4558 
  4559 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4560 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4561 
  4562 
  4563 *** HOL-Complex ***
  4564 
  4565 * Theory RealDef: better support for embedding natural numbers and
  4566 integers in the reals.
  4567 
  4568 The following theorems have been eliminated or modified
  4569 (INCOMPATIBILITY):
  4570 
  4571   exp_ge_add_one_self  now requires no hypotheses
  4572   real_of_int_add      reversed direction of equality (use [symmetric])
  4573   real_of_int_minus    reversed direction of equality (use [symmetric])
  4574   real_of_int_diff     reversed direction of equality (use [symmetric])
  4575   real_of_int_mult     reversed direction of equality (use [symmetric])
  4576 
  4577 * Theory RComplete: expanded support for floor and ceiling functions.
  4578 
  4579 * Theory Ln is new, with properties of the natural logarithm
  4580 
  4581 * Hyperreal: There is a new type constructor "star" for making
  4582 nonstandard types.  The old type names are now type synonyms:
  4583 
  4584   hypreal = real star
  4585   hypnat = nat star
  4586   hcomplex = complex star
  4587 
  4588 * Hyperreal: Many groups of similarly-defined constants have been
  4589 replaced by polymorphic versions (INCOMPATIBILITY):
  4590 
  4591   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4592 
  4593   starset      <-- starsetNat, starsetC
  4594   *s*          <-- *sNat*, *sc*
  4595   starset_n    <-- starsetNat_n, starsetC_n
  4596   *sn*         <-- *sNatn*, *scn*
  4597   InternalSets <-- InternalNatSets, InternalCSets
  4598 
  4599   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4600   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4601   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4602   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4603   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4604 
  4605 * Hyperreal: Many type-specific theorems have been removed in favor of
  4606 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4607 
  4608   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4609   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4610   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4611   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4612   right_minus <-- hypreal_add_minus
  4613   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4614   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4615   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4616   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4617   mult_1_right <-- hcomplex_mult_one_right
  4618   mult_zero_left <-- hcomplex_mult_zero_left
  4619   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4620   right_distrib <-- hypnat_add_mult_distrib2
  4621   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4622   right_inverse <-- hypreal_mult_inverse
  4623   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4624   order_refl <-- {hypreal,hypnat}_le_refl
  4625   order_trans <-- {hypreal,hypnat}_le_trans
  4626   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4627   order_less_le <-- {hypreal,hypnat}_less_le
  4628   linorder_linear <-- {hypreal,hypnat}_le_linear
  4629   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4630   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4631   add_nonneg_nonneg <-- hypreal_le_add_order
  4632 
  4633 * Hyperreal: Separate theorems having to do with type-specific
  4634 versions of constants have been merged into theorems that apply to the
  4635 new polymorphic constants (INCOMPATIBILITY):
  4636 
  4637   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4638   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4639   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4640   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4641   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4642   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4643   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4644   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4645   STAR_diff <-- {STAR,STARC}_diff
  4646   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4647     STARC_hcomplex_of_complex}_image_subset
  4648   starset_n_Un <-- starset{Nat,C}_n_Un
  4649   starset_n_Int <-- starset{Nat,C}_n_Int
  4650   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4651   starset_n_diff <-- starset{Nat,C}_n_diff
  4652   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4653   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4654   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4655   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4656   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4657   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4658   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4659   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4660   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4661   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4662   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4663   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4664   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4665   starfun_diff <-- starfun{C,RC,CR}_diff
  4666   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4667   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4668   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4669   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4670   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4671   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4672   starfun_Id <-- starfunC_Id
  4673   starfun_approx <-- starfun{Nat,CR}_approx
  4674   starfun_capprox <-- starfun{C,RC}_capprox
  4675   starfun_abs <-- starfunNat_rabs
  4676   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4677   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4678   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4679   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4680   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4681   starfun_add_approx <-- starfunCR_add_approx
  4682   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4683   starfun_divide <-- starfun{C,CR,RC}_divide
  4684   starfun_n <-- starfun{Nat,C}_n
  4685   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4686   starfun_n_add <-- starfun{Nat,C}_n_add
  4687   starfun_n_add_minus <-- starfunNat_n_add_minus
  4688   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4689   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4690   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4691 
  4692   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4693   star_n_minus <-- {hypreal,hcomplex}_minus
  4694   star_n_diff <-- {hypreal,hcomplex}_diff
  4695   star_n_mult <-- {hypreal,hcomplex}_mult
  4696   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4697   star_n_le <-- {hypreal,hypnat}_le
  4698   star_n_less <-- {hypreal,hypnat}_less
  4699   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4700   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4701   star_n_abs <-- hypreal_hrabs
  4702   star_n_divide <-- hcomplex_divide
  4703 
  4704   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4705   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4706   star_of_diff <-- hypreal_of_real_diff
  4707   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4708   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4709   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4710   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4711   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4712   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4713   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4714   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4715   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4716   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4717   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4718   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4719   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4720   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4721   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4722   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4723   star_of_power <-- hypreal_of_real_power
  4724   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4725 
  4726 * Hyperreal: new method "transfer" that implements the transfer
  4727 principle of nonstandard analysis. With a subgoal that mentions
  4728 nonstandard types like "'a star", the command "apply transfer"
  4729 replaces it with an equivalent one that mentions only standard types.
  4730 To be successful, all free variables must have standard types; non-
  4731 standard variables must have explicit universal quantifiers.
  4732 
  4733 * Hyperreal: A theory of Taylor series.
  4734 
  4735 
  4736 *** HOLCF ***
  4737 
  4738 * Discontinued special version of 'constdefs' (which used to support
  4739 continuous functions) in favor of the general Pure one with full
  4740 type-inference.
  4741 
  4742 * New simplification procedure for solving continuity conditions; it
  4743 is much faster on terms with many nested lambda abstractions (cubic
  4744 instead of exponential time).
  4745 
  4746 * New syntax for domain package: selector names are now optional.
  4747 Parentheses should be omitted unless argument is lazy, for example:
  4748 
  4749   domain 'a stream = cons "'a" (lazy "'a stream")
  4750 
  4751 * New command 'fixrec' for defining recursive functions with pattern
  4752 matching; defining multiple functions with mutual recursion is also
  4753 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4754 sinr, or any data constructor defined by the domain package. The given
  4755 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4756 syntax and examples.
  4757 
  4758 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4759 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4760 but the proof obligation additionally includes an admissibility
  4761 requirement. The packages generate instances of class cpo or pcpo,
  4762 with continuity and strictness theorems for Rep and Abs.
  4763 
  4764 * HOLCF: Many theorems have been renamed according to a more standard naming
  4765 scheme (INCOMPATIBILITY):
  4766 
  4767   foo_inject:  "foo$x = foo$y ==> x = y"
  4768   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4769   foo_less:    "(foo$x << foo$y) = (x << y)"
  4770   foo_strict:  "foo$UU = UU"
  4771   foo_defined: "... ==> foo$x ~= UU"
  4772   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4773 
  4774 
  4775 *** ZF ***
  4776 
  4777 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4778 including the First Isomorphism Theorem (on quotienting by the kernel
  4779 of a homomorphism).
  4780 
  4781 * ZF/Simplifier: install second copy of type solver that actually
  4782 makes use of TC rules declared to Isar proof contexts (or locales);
  4783 the old version is still required for ML proof scripts.
  4784 
  4785 
  4786 *** Cube ***
  4787 
  4788 * Converted to Isar theory format; use locales instead of axiomatic
  4789 theories.
  4790 
  4791 
  4792 *** ML ***
  4793 
  4794 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4795 for ||>, ||>>, |>>,
  4796 
  4797 * Pure/library.ML no longer defines its own option datatype, but uses
  4798 that of the SML basis, which has constructors NONE and SOME instead of
  4799 None and Some, as well as exception Option.Option instead of OPTION.
  4800 The functions the, if_none, is_some, is_none have been adapted
  4801 accordingly, while Option.map replaces apsome.
  4802 
  4803 * Pure/library.ML: the exception LIST has been given up in favour of
  4804 the standard exceptions Empty and Subscript, as well as
  4805 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4806 superceded by the standard hd and tl functions etc.
  4807 
  4808 A number of basic list functions are no longer exported to the ML
  4809 toplevel, as they are variants of predefined functions.  The following
  4810 suggests how one can translate existing code:
  4811 
  4812     rev_append xs ys = List.revAppend (xs, ys)
  4813     nth_elem (i, xs) = List.nth (xs, i)
  4814     last_elem xs = List.last xs
  4815     flat xss = List.concat xss
  4816     seq fs = List.app fs
  4817     partition P xs = List.partition P xs
  4818     mapfilter f xs = List.mapPartial f xs
  4819 
  4820 * Pure/library.ML: several combinators for linear functional
  4821 transformations, notably reverse application and composition:
  4822 
  4823   x |> f                f #> g
  4824   (x, y) |-> f          f #-> g
  4825 
  4826 * Pure/library.ML: introduced/changed precedence of infix operators:
  4827 
  4828   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4829   infix 2 ?;
  4830   infix 3 o oo ooo oooo;
  4831   infix 4 ~~ upto downto;
  4832 
  4833 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4834 infix operators.
  4835 
  4836 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4837 fold_map support linear functional transformations and nesting.  For
  4838 example:
  4839 
  4840   fold f [x1, ..., xN] y =
  4841     y |> f x1 |> ... |> f xN
  4842 
  4843   (fold o fold) f [xs1, ..., xsN] y =
  4844     y |> fold f xs1 |> ... |> fold f xsN
  4845 
  4846   fold f [x1, ..., xN] =
  4847     f x1 #> ... #> f xN
  4848 
  4849   (fold o fold) f [xs1, ..., xsN] =
  4850     fold f xs1 #> ... #> fold f xsN
  4851 
  4852 * Pure/library.ML: the following selectors on type 'a option are
  4853 available:
  4854 
  4855   the:               'a option -> 'a  (*partial*)
  4856   these:             'a option -> 'a  where 'a = 'b list
  4857   the_default: 'a -> 'a option -> 'a
  4858   the_list:          'a option -> 'a list
  4859 
  4860 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4861 basic operations for association lists, following natural argument
  4862 order; moreover the explicit equality predicate passed here avoids
  4863 potentially expensive polymorphic runtime equality checks.
  4864 The old functions may be expressed as follows:
  4865 
  4866   assoc = uncurry (AList.lookup (op =))
  4867   assocs = these oo AList.lookup (op =)
  4868   overwrite = uncurry (AList.update (op =)) o swap
  4869 
  4870 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4871 
  4872   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4873   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4874 
  4875 replacing make_keylist and keyfilter (occassionally used)
  4876 Naive rewrites:
  4877 
  4878   make_keylist = AList.make
  4879   keyfilter = AList.find (op =)
  4880 
  4881 * eq_fst and eq_snd now take explicit equality parameter, thus
  4882   avoiding eqtypes. Naive rewrites:
  4883 
  4884     eq_fst = eq_fst (op =)
  4885     eq_snd = eq_snd (op =)
  4886 
  4887 * Removed deprecated apl and apr (rarely used).
  4888   Naive rewrites:
  4889 
  4890     apl (n, op) =>>= curry op n
  4891     apr (op, m) =>>= fn n => op (n, m)
  4892 
  4893 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4894 provides a reasonably efficient light-weight implementation of sets as
  4895 lists.
  4896 
  4897 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4898 few new operations; existing lookup and update are now curried to
  4899 follow natural argument order (for use with fold etc.);
  4900 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4901 
  4902 * Pure/General: output via the Isabelle channels of
  4903 writeln/warning/error etc. is now passed through Output.output, with a
  4904 hook for arbitrary transformations depending on the print_mode
  4905 (cf. Output.add_mode -- the first active mode that provides a output
  4906 function wins).  Already formatted output may be embedded into further
  4907 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4908 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4909 accommodate easy composition of diagnostic messages etc.  Programmers
  4910 rarely need to care about Output.output or Output.raw at all, with
  4911 some notable exceptions: Output.output is required when bypassing the
  4912 standard channels (writeln etc.), or in token translations to produce
  4913 properly formatted results; Output.raw is required when capturing
  4914 already output material that will eventually be presented to the user
  4915 a second time.  For the default print mode, both Output.output and
  4916 Output.raw have no effect.
  4917 
  4918 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4919 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4920 cumulative results are displayed at the end of a batch session.
  4921 
  4922 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4923 replaced by File.platform_path and File.shell_path (with appropriate
  4924 hooks).  This provides a clean interface for unusual systems where the
  4925 internal and external process view of file names are different.
  4926 
  4927 * Pure: more efficient orders for basic syntactic entities: added
  4928 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4929 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4930 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4931 orders now -- potential INCOMPATIBILITY for code that depends on a
  4932 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4933 Library.sort_strings on result).
  4934 
  4935 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4936 fold_types traverse types/terms from left to right, observing natural
  4937 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4938 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4939 
  4940 * Pure: name spaces have been refined, with significant changes of the
  4941 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4942 to extern(_table).  The plain name entry path is superceded by a
  4943 general 'naming' context, which also includes the 'policy' to produce
  4944 a fully qualified name and external accesses of a fully qualified
  4945 name; NameSpace.extend is superceded by context dependent
  4946 Sign.declare_name.  Several theory and proof context operations modify
  4947 the naming context.  Especially note Theory.restore_naming and
  4948 ProofContext.restore_naming to get back to a sane state; note that
  4949 Theory.add_path is no longer sufficient to recover from
  4950 Theory.absolute_path in particular.
  4951 
  4952 * Pure: new flags short_names (default false) and unique_names
  4953 (default true) for controlling output of qualified names.  If
  4954 short_names is set, names are printed unqualified.  If unique_names is
  4955 reset, the name prefix is reduced to the minimum required to achieve
  4956 the original result when interning again, even if there is an overlap
  4957 with earlier declarations.
  4958 
  4959 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4960 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4961 (useful for printing error messages).  INCOMPATIBILITY.
  4962 
  4963 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4964 Theory.theory are now identified, referring to the universal
  4965 Context.theory (see Pure/context.ML).  Actual signature and theory
  4966 content is managed as theory data.  The old code and interfaces were
  4967 spread over many files and structures; the new arrangement introduces
  4968 considerable INCOMPATIBILITY to gain more clarity:
  4969 
  4970   Context -- theory management operations (name, identity, inclusion,
  4971     parents, ancestors, merge, etc.), plus generic theory data;
  4972 
  4973   Sign -- logical signature and syntax operations (declaring consts,
  4974     types, etc.), plus certify/read for common entities;
  4975 
  4976   Theory -- logical theory operations (stating axioms, definitions,
  4977     oracles), plus a copy of logical signature operations (consts,
  4978     types, etc.); also a few basic management operations (Theory.copy,
  4979     Theory.merge, etc.)
  4980 
  4981 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4982 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4983 for convenience -- they merely return the theory.
  4984 
  4985 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4986 
  4987 * Pure: the Isar proof context type is already defined early in Pure
  4988 as Context.proof (note that ProofContext.context and Proof.context are
  4989 aliases, where the latter is the preferred name).  This enables other
  4990 Isabelle components to refer to that type even before Isar is present.
  4991 
  4992 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4993 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4994 any of these kinds.  For example, Sign.intern typeK is now
  4995 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4996 Theory.hide_types.  Also note that former
  4997 Theory.hide_classes/types/consts are now
  4998 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4999 internalize their arguments!  INCOMPATIBILITY.
  5000 
  5001 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5002 datatype thmref (with constructors Name and NameSelection) instead of
  5003 plain string -- INCOMPATIBILITY;
  5004 
  5005 * Pure: cases produced by proof methods specify options, where NONE
  5006 means to remove case bindings -- INCOMPATIBILITY in
  5007 (RAW_)METHOD_CASES.
  5008 
  5009 * Pure: the following operations retrieve axioms or theorems from a
  5010 theory node or theory hierarchy, respectively:
  5011 
  5012   Theory.axioms_of: theory -> (string * term) list
  5013   Theory.all_axioms_of: theory -> (string * term) list
  5014   PureThy.thms_of: theory -> (string * thm) list
  5015   PureThy.all_thms_of: theory -> (string * thm) list
  5016 
  5017 * Pure: print_tac now outputs the goal through the trace channel.
  5018 
  5019 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5020 Reference Toplevel.debug (default false) controls detailed printing
  5021 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5022 controls execution profiling -- set to 1 for time and 2 for space
  5023 (both increase the runtime).
  5024 
  5025 * Isar session: The initial use of ROOT.ML is now always timed,
  5026 i.e. the log will show the actual process times, in contrast to the
  5027 elapsed wall-clock time that the outer shell wrapper produces.
  5028 
  5029 * Simplifier: improved handling of bound variables (nameless
  5030 representation, avoid allocating new strings).  Simprocs that invoke
  5031 the Simplifier recursively should use Simplifier.inherit_bounds to
  5032 avoid local name clashes.  Failure to do so produces warnings
  5033 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5034 for further details.
  5035 
  5036 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5037 bindings for all theorems stored within a given theory; this may help
  5038 in porting non-Isar theories to Isar ones, while keeping ML proof
  5039 scripts for the time being.
  5040 
  5041 * ML operator HTML.with_charset specifies the charset begin used for
  5042 generated HTML files.  For example:
  5043 
  5044   HTML.with_charset "utf-8" use_thy "Hebrew";
  5045   HTML.with_charset "utf-8" use_thy "Chinese";
  5046 
  5047 
  5048 *** System ***
  5049 
  5050 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5051 isabelle, isatool etc.).
  5052 
  5053 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5054 isatool doc, isatool mkdir, display_drafts etc.).
  5055 
  5056 * isatool usedir: option -f allows specification of the ML file to be
  5057 used by Isabelle; default is ROOT.ML.
  5058 
  5059 * New isatool version outputs the version identifier of the Isabelle
  5060 distribution being used.
  5061 
  5062 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5063 (containing Boolean satisfiability problems) into Isabelle/HOL
  5064 theories.
  5065 
  5066 
  5067 
  5068 New in Isabelle2004 (April 2004)
  5069 --------------------------------
  5070 
  5071 *** General ***
  5072 
  5073 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5074   Replaces linorder.ML.
  5075 
  5076 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5077   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5078   (\<a>...\<z>), are now considered normal letters, and can therefore
  5079   be used anywhere where an ASCII letter (a...zA...Z) has until
  5080   now. COMPATIBILITY: This obviously changes the parsing of some
  5081   terms, especially where a symbol has been used as a binder, say
  5082   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5083   as an identifier.  Fix it by inserting a space around former
  5084   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5085   existing theory and ML files.
  5086 
  5087 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5088 
  5089 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5090   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5091   a normal (but invisible) letter. For multiple letter subscripts repeat
  5092   \<^isub> like this: x\<^isub>1\<^isub>2.
  5093 
  5094 * Pure: There are now sub-/superscripts that can span more than one
  5095   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5096   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5097   superscript. The new control characters are not identifier parts.
  5098 
  5099 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5100   content of "..." to the latex file instead of \isacntrl... . The "..."
  5101   may consist of any printable characters excluding the end bracket >.
  5102 
  5103 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5104   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5105   declare constants "final", which prevents their being given a definition
  5106   later.  It is useful for constants whose behaviour is fixed axiomatically
  5107   rather than definitionally, such as the meta-logic connectives.
  5108 
  5109 * Pure: 'instance' now handles general arities with general sorts
  5110   (i.e. intersections of classes),
  5111 
  5112 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5113   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5114   It can be changed to alter the colors/layout of generated pages.
  5115 
  5116 
  5117 *** Isar ***
  5118 
  5119 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5120   cut_tac, subgoal_tac and thin_tac:
  5121   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5122     locales are no longer forced to write Isar proof scripts.
  5123     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5124     emulations.
  5125   - INCOMPATIBILITY: names of variables to be instantiated may no
  5126     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5127     This is consistent with the instantiation attribute "where".
  5128 
  5129 * Attributes "where" and "of":
  5130   - Now take type variables of instantiated theorem into account when reading
  5131     the instantiation string.  This fixes a bug that caused instantiated
  5132     theorems to have too special types in some circumstances.
  5133   - "where" permits explicit instantiations of type variables.
  5134 
  5135 * Calculation commands "moreover" and "also" no longer interfere with
  5136   current facts ("this"), admitting arbitrary combinations with "then"
  5137   and derived forms.
  5138 
  5139 * Locales:
  5140   - Goal statements involving the context element "includes" no longer
  5141     generate theorems with internal delta predicates (those ending on
  5142     "_axioms") in the premise.
  5143     Resolve particular premise with <locale>.intro to obtain old form.
  5144   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5145     specification and "includes" elements in goal statement.
  5146   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5147     [intro?] and [elim?] (respectively) by default.
  5148   - Experimental command for instantiation of locales in proof contexts:
  5149         instantiate <label>[<attrs>]: <loc>
  5150     Instantiates locale <loc> and adds all its theorems to the current context
  5151     taking into account their attributes.  Label and attrs are optional
  5152     modifiers, like in theorem declarations.  If present, names of
  5153     instantiated theorems are qualified with <label>, and the attributes
  5154     <attrs> are applied after any attributes these theorems might have already.
  5155       If the locale has assumptions, a chained fact of the form
  5156     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5157     are derived.  The command does not support old-style locales declared
  5158     with "locale (open)".
  5159       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5160 
  5161 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5162   (Isar) contexts.
  5163 
  5164 
  5165 *** HOL ***
  5166 
  5167 * Proof import: new image HOL4 contains the imported library from
  5168   the HOL4 system with about 2500 theorems. It is imported by
  5169   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5170   can be used like any other Isabelle image.  See
  5171   HOL/Import/HOL/README for more information.
  5172 
  5173 * Simplifier:
  5174   - Much improved handling of linear and partial orders.
  5175     Reasoners for linear and partial orders are set up for type classes
  5176     "linorder" and "order" respectively, and are added to the default simpset
  5177     as solvers.  This means that the simplifier can build transitivity chains
  5178     to solve goals from the assumptions.
  5179   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5180     of blast or auto after simplification become unnecessary because the goal
  5181     is solved by simplification already.
  5182 
  5183 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5184     all proved in axiomatic type classes for semirings, rings and fields.
  5185 
  5186 * Numerics:
  5187   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5188     now formalized using the Ring_and_Field theory mentioned above.
  5189   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5190     than before, because now they are set up once in a generic manner.
  5191   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5192     Look for the general versions in Ring_and_Field (and Power if they concern
  5193     exponentiation).
  5194 
  5195 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5196 
  5197 * Records:
  5198   - Record types are now by default printed with their type abbreviation
  5199     instead of the list of all field types. This can be configured via
  5200     the reference "print_record_type_abbr".
  5201   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5202     (not enabled by default).
  5203   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5204     EX x. x = sel r to True (not enabled by default).
  5205   - Tactic "record_split_simp_tac" to split and simplify records added.
  5206 
  5207 * 'specification' command added, allowing for definition by
  5208   specification.  There is also an 'ax_specification' command that
  5209   introduces the new constants axiomatically.
  5210 
  5211 * arith(_tac) is now able to generate counterexamples for reals as well.
  5212 
  5213 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5214 
  5215 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5216   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5217 
  5218 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5219   matrix theory to linear programming.
  5220 
  5221 * Unions and Intersections:
  5222   The latex output syntax of UN and INT has been changed
  5223   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5224   i.e. the index formulae has become a subscript.
  5225   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5226 
  5227 * Unions and Intersections over Intervals:
  5228   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5229   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5230   like in normal math, and corresponding versions for < and for intersection.
  5231 
  5232 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5233   lexicographic dictonary ordering has been added as "lexord".
  5234 
  5235 * ML: the legacy theory structures Int and List have been removed. They had
  5236   conflicted with ML Basis Library structures having the same names.
  5237 
  5238 * 'refute' command added to search for (finite) countermodels.  Only works
  5239   for a fragment of HOL.  The installation of an external SAT solver is
  5240   highly recommended.  See "HOL/Refute.thy" for details.
  5241 
  5242 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5243   formulae under an assignment of free variables to random values.
  5244   In contrast to 'refute', it can deal with inductive datatypes,
  5245   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5246   for examples.
  5247 
  5248 
  5249 *** HOLCF ***
  5250 
  5251 * Streams now come with concatenation and are part of the HOLCF image
  5252 
  5253 
  5254 
  5255 New in Isabelle2003 (May 2003)
  5256 ------------------------------
  5257 
  5258 *** General ***
  5259 
  5260 * Provers/simplifier:
  5261 
  5262   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5263     Assumptions are now subject to complete mutual simplification,
  5264     not just from left to right. The simplifier now preserves
  5265     the order of assumptions.
  5266 
  5267     Potential INCOMPATIBILITY:
  5268 
  5269     -- simp sometimes diverges where the old version did
  5270        not, e.g. invoking simp on the goal
  5271 
  5272         [| P (f x); y = x; f x = f y |] ==> Q
  5273 
  5274        now gives rise to the infinite reduction sequence
  5275 
  5276         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5277 
  5278        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5279        kind of problem.
  5280 
  5281     -- Tactics combining classical reasoner and simplification (such as auto)
  5282        are also affected by this change, because many of them rely on
  5283        simp. They may sometimes diverge as well or yield a different numbers
  5284        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5285        in case of problems. Sometimes subsequent calls to the classical
  5286        reasoner will fail because a preceeding call to the simplifier too
  5287        eagerly simplified the goal, e.g. deleted redundant premises.
  5288 
  5289   - The simplifier trace now shows the names of the applied rewrite rules
  5290 
  5291   - You can limit the number of recursive invocations of the simplifier
  5292     during conditional rewriting (where the simplifie tries to solve the
  5293     conditions before applying the rewrite rule):
  5294     ML "simp_depth_limit := n"
  5295     where n is an integer. Thus you can force termination where previously
  5296     the simplifier would diverge.
  5297 
  5298   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5299 
  5300   - No longer aborts on failed congruence proof.  Instead, the
  5301     congruence is ignored.
  5302 
  5303 * Pure: New generic framework for extracting programs from constructive
  5304   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5305   as HOL/Extraction for some case studies.
  5306 
  5307 * Pure: The main goal of the proof state is no longer shown by default, only
  5308 the subgoals. This behaviour is controlled by a new flag.
  5309    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5310 (ML: Proof.show_main_goal).
  5311 
  5312 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5313 rules whose conclusion matches subgoal 1:
  5314       PG menu: Isabelle/Isar -> Show me -> matching rules
  5315 The rules are ordered by how closely they match the subgoal.
  5316 In particular, rules that solve a subgoal outright are displayed first
  5317 (or rather last, the way they are printed).
  5318 (ML: ProofGeneral.print_intros())
  5319 
  5320 * Pure: New flag trace_unify_fail causes unification to print
  5321 diagnostic information (PG: in trace buffer) when it fails. This is
  5322 useful for figuring out why single step proofs like rule, erule or
  5323 assumption failed.
  5324 
  5325 * Pure: Locale specifications now produce predicate definitions
  5326 according to the body of text (covering assumptions modulo local
  5327 definitions); predicate "loc_axioms" covers newly introduced text,
  5328 while "loc" is cumulative wrt. all included locale expressions; the
  5329 latter view is presented only on export into the global theory
  5330 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5331 on the old view without predicates;
  5332 
  5333 * Pure: predefined locales "var" and "struct" are useful for sharing
  5334 parameters (as in CASL, for example); just specify something like
  5335 ``var x + var y + struct M'' as import;
  5336 
  5337 * Pure: improved thms_containing: proper indexing of facts instead of
  5338 raw theorems; check validity of results wrt. current name space;
  5339 include local facts of proof configuration (also covers active
  5340 locales), cover fixed variables in index; may use "_" in term
  5341 specification; an optional limit for the number of printed facts may
  5342 be given (the default is 40);
  5343 
  5344 * Pure: disallow duplicate fact bindings within new-style theory files
  5345 (batch-mode only);
  5346 
  5347 * Provers: improved induct method: assumptions introduced by case
  5348 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5349 the goal statement); "foo" still refers to all facts collectively;
  5350 
  5351 * Provers: the function blast.overloaded has been removed: all constants
  5352 are regarded as potentially overloaded, which improves robustness in exchange
  5353 for slight decrease in efficiency;
  5354 
  5355 * Provers/linorder: New generic prover for transitivity reasoning over
  5356 linear orders.  Note: this prover is not efficient!
  5357 
  5358 * Isar: preview of problems to finish 'show' now produce an error
  5359 rather than just a warning (in interactive mode);
  5360 
  5361 
  5362 *** HOL ***
  5363 
  5364 * arith(_tac)
  5365 
  5366  - Produces a counter example if it cannot prove a goal.
  5367    Note that the counter example may be spurious if the goal is not a formula
  5368    of quantifier-free linear arithmetic.
  5369    In ProofGeneral the counter example appears in the trace buffer.
  5370 
  5371  - Knows about div k and mod k where k is a numeral of type nat or int.
  5372 
  5373  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5374    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5375    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5376 
  5377 * simp's arithmetic capabilities have been enhanced a bit: it now
  5378 takes ~= in premises into account (by performing a case split);
  5379 
  5380 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5381 are distributed over a sum of terms;
  5382 
  5383 * New tactic "trans_tac" and method "trans" instantiate
  5384 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5385 "<=", "<" and "=").
  5386 
  5387 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5388 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5389 
  5390 * 'typedef' command has new option "open" to suppress the set
  5391 definition;
  5392 
  5393 * functions Min and Max on finite sets have been introduced (theory
  5394 Finite_Set);
  5395 
  5396 * attribute [symmetric] now works for relations as well; it turns
  5397 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5398 
  5399 * induct over a !!-quantified statement (say !!x1..xn):
  5400   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5401 
  5402 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5403 %x. None. Warning: empty_def now refers to the previously hidden definition
  5404 of the empty set.
  5405 
  5406 * Algebra: formalization of classical algebra.  Intended as base for
  5407 any algebraic development in Isabelle.  Currently covers group theory
  5408 (up to Sylow's theorem) and ring theory (Universal Property of
  5409 Univariate Polynomials).  Contributions welcome;
  5410 
  5411 * GroupTheory: deleted, since its material has been moved to Algebra;
  5412 
  5413 * Complex: new directory of the complex numbers with numeric constants,
  5414 nonstandard complex numbers, and some complex analysis, standard and
  5415 nonstandard (Jacques Fleuriot);
  5416 
  5417 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5418 
  5419 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5420 Fleuriot);
  5421 
  5422 * Real/HahnBanach: updated and adapted to locales;
  5423 
  5424 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5425 Gray and Kramer);
  5426 
  5427 * UNITY: added the Meier-Sanders theory of progress sets;
  5428 
  5429 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5430 as abstract algorithms, instantiated to the JVM;
  5431 
  5432 * Bali: Java source language formalization. Type system, operational
  5433 semantics, axiomatic semantics. Supported language features:
  5434 classes, interfaces, objects,virtual methods, static methods,
  5435 static/instance fields, arrays, access modifiers, definite
  5436 assignment, exceptions.
  5437 
  5438 
  5439 *** ZF ***
  5440 
  5441 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5442 universe, etc.);
  5443 
  5444 * Main ZF: virtually all theories converted to new-style format;
  5445 
  5446 
  5447 *** ML ***
  5448 
  5449 * Pure: Tactic.prove provides sane interface for internal proofs;
  5450 omits the infamous "standard" operation, so this is more appropriate
  5451 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5452 
  5453 * Pure: improved error reporting of simprocs;
  5454 
  5455 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5456 up simprocs;
  5457 
  5458 
  5459 *** Document preparation ***
  5460 
  5461 * uses \par instead of \\ for line breaks in theory text. This may
  5462 shift some page breaks in large documents. To get the old behaviour
  5463 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5464 
  5465 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5466 other packages
  5467 
  5468 * \<euro> now needs package babel/greek instead of marvosym (which
  5469 broke \Rightarrow)
  5470 
  5471 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5472 textcomp package)
  5473 
  5474 
  5475 
  5476 New in Isabelle2002 (March 2002)
  5477 --------------------------------
  5478 
  5479 *** Document preparation ***
  5480 
  5481 * greatly simplified document preparation setup, including more
  5482 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5483 instructive isatool mkdir; users should basically be able to get
  5484 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5485 users may run a separate document processing stage manually like this:
  5486 "isatool usedir -D output HOL Test && isatool document Test/output";
  5487 
  5488 * theory dependency graph may now be incorporated into documents;
  5489 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5490 with \includegraphics of LaTeX;
  5491 
  5492 * proper spacing of consecutive markup elements, especially text
  5493 blocks after section headings;
  5494 
  5495 * support bold style (for single symbols only), input syntax is like
  5496 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5497 
  5498 * \<bullet> is now output as bold \cdot by default, which looks much
  5499 better in printed text;
  5500 
  5501 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5502 note that these symbols are currently unavailable in Proof General /
  5503 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5504 
  5505 * isatool latex no longer depends on changed TEXINPUTS, instead
  5506 isatool document copies the Isabelle style files to the target
  5507 location;
  5508 
  5509 
  5510 *** Isar ***
  5511 
  5512 * Pure/Provers: improved proof by cases and induction;
  5513   - 'case' command admits impromptu naming of parameters (such as
  5514     "case (Suc n)");
  5515   - 'induct' method divinates rule instantiation from the inductive
  5516     claim; no longer requires excessive ?P bindings for proper
  5517     instantiation of cases;
  5518   - 'induct' method properly enumerates all possibilities of set/type
  5519     rules; as a consequence facts may be also passed through *type*
  5520     rules without further ado;
  5521   - 'induct' method now derives symbolic cases from the *rulified*
  5522     rule (before it used to rulify cases stemming from the internal
  5523     atomized version); this means that the context of a non-atomic
  5524     statement becomes is included in the hypothesis, avoiding the
  5525     slightly cumbersome show "PROP ?case" form;
  5526   - 'induct' may now use elim-style induction rules without chaining
  5527     facts, using ``missing'' premises from the goal state; this allows
  5528     rules stemming from inductive sets to be applied in unstructured
  5529     scripts, while still benefitting from proper handling of non-atomic
  5530     statements; NB: major inductive premises need to be put first, all
  5531     the rest of the goal is passed through the induction;
  5532   - 'induct' proper support for mutual induction involving non-atomic
  5533     rule statements (uses the new concept of simultaneous goals, see
  5534     below);
  5535   - append all possible rule selections, but only use the first
  5536     success (no backtracking);
  5537   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5538   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5539   - added 'print_induct_rules' (covered by help item in recent Proof
  5540     General versions);
  5541   - moved induct/cases attributes to Pure, methods to Provers;
  5542   - generic method setup instantiated for FOL and HOL;
  5543 
  5544 * Pure: support multiple simultaneous goal statements, for example
  5545 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5546 meta-level mechanism, this acts as if several individual goals had
  5547 been stated separately; in particular common proof methods need to be
  5548 repeated in order to cover all claims; note that a single elimination
  5549 step is *not* sufficient to establish the two conjunctions, so this
  5550 fails:
  5551 
  5552   assume "A & B" then have A and B ..   (*".." fails*)
  5553 
  5554 better use "obtain" in situations as above; alternative refer to
  5555 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5556 
  5557 * Pure: proper integration with ``locales''; unlike the original
  5558 version by Florian Kammller, Isar locales package high-level proof
  5559 contexts rather than raw logical ones (e.g. we admit to include
  5560 attributes everywhere); operations on locales include merge and
  5561 rename; support for implicit arguments (``structures''); simultaneous
  5562 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5563 some examples;
  5564 
  5565 * Pure: the following commands have been ``localized'', supporting a
  5566 target locale specification "(in name)": 'lemma', 'theorem',
  5567 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5568 stored both within the locale and at the theory level (exported and
  5569 qualified by the locale name);
  5570 
  5571 * Pure: theory goals may now be specified in ``long'' form, with
  5572 ad-hoc contexts consisting of arbitrary locale elements. for example
  5573 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5574 definitions may be given, too); the result is a meta-level rule with
  5575 the context elements being discharged in the obvious way;
  5576 
  5577 * Pure: new proof command 'using' allows to augment currently used
  5578 facts after a goal statement ('using' is syntactically analogous to
  5579 'apply', but acts on the goal's facts only); this allows chained facts
  5580 to be separated into parts given before and after a claim, as in
  5581 ``from a and b have C using d and e <proof>'';
  5582 
  5583 * Pure: renamed "antecedent" case to "rule_context";
  5584 
  5585 * Pure: new 'judgment' command records explicit information about the
  5586 object-logic embedding (used by several tools internally); no longer
  5587 use hard-wired "Trueprop";
  5588 
  5589 * Pure: added 'corollary' command;
  5590 
  5591 * Pure: fixed 'token_translation' command;
  5592 
  5593 * Pure: removed obsolete 'exported' attribute;
  5594 
  5595 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5596 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5597 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5598 
  5599 * Pure: method 'atomize' presents local goal premises as object-level
  5600 statements (atomic meta-level propositions); setup controlled via
  5601 rewrite rules declarations of 'atomize' attribute; example
  5602 application: 'induct' method with proper rule statements in improper
  5603 proof *scripts*;
  5604 
  5605 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5606 now consider the syntactic context of assumptions, giving a better
  5607 chance to get type-inference of the arguments right (this is
  5608 especially important for locales);
  5609 
  5610 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5611 mode;
  5612 
  5613 * Pure/obtain: the formal conclusion "thesis", being marked as
  5614 ``internal'', may no longer be reference directly in the text;
  5615 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5616 situations;
  5617 
  5618 * Pure: generic 'sym' attribute which declares a rule both as pure
  5619 'elim?' and for the 'symmetric' operation;
  5620 
  5621 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5622 text; the fixed correlation with particular command syntax has been
  5623 discontinued;
  5624 
  5625 * Pure: new method 'rules' is particularly well-suited for proof
  5626 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5627 but often produces more compact proof terms with less detours;
  5628 
  5629 * Pure/Provers/classical: simplified integration with pure rule
  5630 attributes and methods; the classical "intro?/elim?/dest?"
  5631 declarations coincide with the pure ones; the "rule" method no longer
  5632 includes classically swapped intros; "intro" and "elim" methods no
  5633 longer pick rules from the context; also got rid of ML declarations
  5634 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5635 INCOMPATIBILITY;
  5636 
  5637 * Provers/classical: attribute 'swapped' produces classical inversions
  5638 of introduction rules;
  5639 
  5640 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5641 rules instead of full simplifier context; 'iff' attribute handles
  5642 conditional rules;
  5643 
  5644 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5645 
  5646 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5647 "(permissive)" option to recover old behavior;
  5648 
  5649 * HOL: 'inductive' no longer features separate (collective) attributes
  5650 for 'intros' (was found too confusing);
  5651 
  5652 * HOL: properly declared induction rules less_induct and
  5653 wf_induct_rule;
  5654 
  5655 
  5656 *** HOL ***
  5657 
  5658 * HOL: moved over to sane numeral syntax; the new policy is as
  5659 follows:
  5660 
  5661   - 0 and 1 are polymorphic constants, which are defined on any
  5662   numeric type (nat, int, real etc.);
  5663 
  5664   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5665   binary representation internally;
  5666 
  5667   - type nat has special constructor Suc, and generally prefers Suc 0
  5668   over 1::nat and Suc (Suc 0) over 2::nat;
  5669 
  5670 This change may cause significant problems of INCOMPATIBILITY; here
  5671 are some hints on converting existing sources:
  5672 
  5673   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5674   entities, so expressions involving "-" (unary or binary minus) need
  5675   to be spaced properly;
  5676 
  5677   - existing occurrences of "1" may need to be constraint "1::nat" or
  5678   even replaced by Suc 0; similar for old "2";
  5679 
  5680   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5681 
  5682   - remove all special provisions on numerals in proofs;
  5683 
  5684 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5685 representation (depends on bin_arith_simps in the default context);
  5686 
  5687 * HOL: symbolic syntax for x^2 (numeral 2);
  5688 
  5689 * HOL: the class of all HOL types is now called "type" rather than
  5690 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5691 in axclass/classes, instance/arities, and (usually rare) occurrences
  5692 in typings (of consts etc.); internally the class is called
  5693 "HOL.type", ML programs should refer to HOLogic.typeS;
  5694 
  5695 * HOL/record package improvements:
  5696   - new derived operations "fields" to build a partial record section,
  5697     "extend" to promote a fixed record to a record scheme, and
  5698     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5699     declared as simp by default;
  5700   - shared operations ("more", "fields", etc.) now need to be always
  5701     qualified) --- potential INCOMPATIBILITY;
  5702   - removed "make_scheme" operations (use "make" with "extend") --
  5703     INCOMPATIBILITY;
  5704   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5705   - provides cases/induct rules for use with corresponding Isar
  5706     methods (for concrete records, record schemes, concrete more
  5707     parts, and schematic more parts -- in that order);
  5708   - internal definitions directly based on a light-weight abstract
  5709     theory of product types over typedef rather than datatype;
  5710 
  5711 * HOL: generic code generator for generating executable ML code from
  5712 specifications; specific support for HOL constructs such as inductive
  5713 datatypes and sets, as well as recursive functions; can be invoked
  5714 via 'generate_code' theory section;
  5715 
  5716 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5717 
  5718 * HOL: consolidated and renamed several theories.  In particular:
  5719         Ord.thy has been absorbed into HOL.thy
  5720         String.thy has been absorbed into List.thy
  5721 
  5722 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5723 (beware of argument permutation!);
  5724 
  5725 * HOL: linorder_less_split superseded by linorder_cases;
  5726 
  5727 * HOL/List: "nodups" renamed to "distinct";
  5728 
  5729 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5730 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5731   - Ex_def has changed, now need to use some_eq_ex
  5732 
  5733 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5734 in this (rare) case use:
  5735 
  5736   delSWrapper "split_all_tac"
  5737   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5738 
  5739 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5740 MAY FAIL;
  5741 
  5742 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5743 Isabelle's type classes, ^ on functions and relations has too general
  5744 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5745 necessary to attach explicit type constraints;
  5746 
  5747 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5748 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5749 renamed accordingly (eg "compI" -> "rel_compI").
  5750 
  5751 * HOL: syntax translations now work properly with numerals and records
  5752 expressions;
  5753 
  5754 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5755 of "lam" -- INCOMPATIBILITY;
  5756 
  5757 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5758 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5759 renamed "Product_Type.unit";
  5760 
  5761 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5762 
  5763 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5764 the "cases" method);
  5765 
  5766 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5767 Florian Kammller);
  5768 
  5769 * HOL/IMP: updated and converted to new-style theory format; several
  5770 parts turned into readable document, with proper Isar proof texts and
  5771 some explanations (by Gerwin Klein);
  5772 
  5773 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5774 
  5775 * HOL-Hyperreal is now a logic image;
  5776 
  5777 
  5778 *** HOLCF ***
  5779 
  5780 * Isar: consts/constdefs supports mixfix syntax for continuous
  5781 operations;
  5782 
  5783 * Isar: domain package adapted to new-style theory format, e.g. see
  5784 HOLCF/ex/Dnat.thy;
  5785 
  5786 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5787 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5788 lift.induct_tac, always use UU instead of Undef;
  5789 
  5790 * HOLCF/IMP: updated and converted to new-style theory;
  5791 
  5792 
  5793 *** ZF ***
  5794 
  5795 * Isar: proper integration of logic-specific tools and packages,
  5796 including theory commands '(co)inductive', '(co)datatype',
  5797 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5798 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5799 
  5800 * theory Main no longer includes AC; for the Axiom of Choice, base
  5801 your theory on Main_ZFC;
  5802 
  5803 * the integer library now covers quotients and remainders, with many
  5804 laws relating division to addition, multiplication, etc.;
  5805 
  5806 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5807 typeless version of the formalism;
  5808 
  5809 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5810 format;
  5811 
  5812 * ZF/Induct: new directory for examples of inductive definitions,
  5813 including theory Multiset for multiset orderings; converted to
  5814 new-style theory format;
  5815 
  5816 * ZF: many new theorems about lists, ordinals, etc.;
  5817 
  5818 
  5819 *** General ***
  5820 
  5821 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5822 variable proof controls level of detail: 0 = no proofs (only oracle
  5823 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5824 also ref manual for further ML interfaces;
  5825 
  5826 * Pure/axclass: removed obsolete ML interface
  5827 goal_subclass/goal_arity;
  5828 
  5829 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5830 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5831 separate tokens, so expressions involving minus need to be spaced
  5832 properly;
  5833 
  5834 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5835 rather than "infixl" or "infixr";
  5836 
  5837 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5838 sort constraint specifications in type inference; e.g. "x::_::foo"
  5839 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5840 type variable);
  5841 
  5842 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5843 control output of nested => (types); the default behavior is
  5844 "type_brackets";
  5845 
  5846 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5847 tokens into AST constants;
  5848 
  5849 * Pure/syntax: prefer later declarations of translations and print
  5850 translation functions; potential INCOMPATIBILITY: need to reverse
  5851 multiple declarations for same syntax element constant;
  5852 
  5853 * Pure/show_hyps reset by default (in accordance to existing Isar
  5854 practice);
  5855 
  5856 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5857 addSafter;
  5858 
  5859 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5860 as well;
  5861 
  5862 * system: tested support for MacOS X; should be able to get Isabelle +
  5863 Proof General to work in a plain Terminal after installing Poly/ML
  5864 (e.g. from the Isabelle distribution area) and GNU bash alone
  5865 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5866 support requires further installations, e.g. from
  5867 http://fink.sourceforge.net/);
  5868 
  5869 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5870 
  5871 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5872 of 40 MB), cf. ML_OPTIONS;
  5873 
  5874 * system: Proof General keywords specification is now part of the
  5875 Isabelle distribution (see etc/isar-keywords.el);
  5876 
  5877 * system: support for persistent Proof General sessions (refrain from
  5878 outdating all loaded theories on startup); user may create writable
  5879 logic images like this: ``isabelle -q HOL Test'';
  5880 
  5881 * system: smart selection of Isabelle process versus Isabelle
  5882 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5883 run both "isabelle" and "Isabelle" even if file names are badly
  5884 damaged (executable inspects the case of the first letter of its own
  5885 name); added separate "isabelle-process" and "isabelle-interface";
  5886 
  5887 * system: refrain from any attempt at filtering input streams; no
  5888 longer support ``8bit'' encoding of old isabelle font, instead proper
  5889 iso-latin characters may now be used; the related isatools
  5890 "symbolinput" and "nonascii" have disappeared as well;
  5891 
  5892 * system: removed old "xterm" interface (the print modes "xterm" and
  5893 "xterm_color" are still available for direct use in a suitable
  5894 terminal);
  5895 
  5896 
  5897 
  5898 New in Isabelle99-2 (February 2001)
  5899 -----------------------------------
  5900 
  5901 *** Overview of INCOMPATIBILITIES ***
  5902 
  5903 * HOL: please note that theories in the Library and elsewhere often use the
  5904 new-style (Isar) format; to refer to their theorems in an ML script you must
  5905 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5906 
  5907 * HOL: inductive package no longer splits induction rule aggressively,
  5908 but only as far as specified by the introductions given; the old
  5909 format may be recovered via ML function complete_split_rule or attribute
  5910 'split_rule (complete)';
  5911 
  5912 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5913 gfp_Tarski to gfp_unfold;
  5914 
  5915 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5916 
  5917 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5918 relation); infix "^^" has been renamed "``"; infix "``" has been
  5919 renamed "`"; "univalent" has been renamed "single_valued";
  5920 
  5921 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5922 operation;
  5923 
  5924 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5925 
  5926 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5927 
  5928 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5929 consequence, it is no longer monotonic wrt. the local goal context
  5930 (which is now passed through the inductive cases);
  5931 
  5932 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5933 \<gg> to \<ggreater>;
  5934 
  5935 
  5936 *** Document preparation ***
  5937 
  5938 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5939 available: are "it" for near math-mode best-style output, "sl" for
  5940 slanted text style, and "tt" for plain type-writer; if no
  5941 \isabellestyle command is given, output is according to slanted
  5942 type-writer);
  5943 
  5944 * support sub/super scripts (for single symbols only), input syntax is
  5945 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5946 
  5947 * some more standard symbols; see Appendix A of the system manual for
  5948 the complete list of symbols defined in isabellesym.sty;
  5949 
  5950 * improved isabelle style files; more abstract symbol implementation
  5951 (should now use \isamath{...} and \isatext{...} in custom symbol
  5952 definitions);
  5953 
  5954 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5955 state; Note that presentation of goal states does not conform to
  5956 actual human-readable proof documents.  Please do not include goal
  5957 states into document output unless you really know what you are doing!
  5958 
  5959 * proper indentation of antiquoted output with proportional LaTeX
  5960 fonts;
  5961 
  5962 * no_document ML operator temporarily disables LaTeX document
  5963 generation;
  5964 
  5965 * isatool unsymbolize tunes sources for plain ASCII communication;
  5966 
  5967 
  5968 *** Isar ***
  5969 
  5970 * Pure: Isar now suffers initial goal statements to contain unbound
  5971 schematic variables (this does not conform to actual readable proof
  5972 documents, due to unpredictable outcome and non-compositional proof
  5973 checking); users who know what they are doing may use schematic goals
  5974 for Prolog-style synthesis of proven results;
  5975 
  5976 * Pure: assumption method (an implicit finishing) now handles actual
  5977 rules as well;
  5978 
  5979 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5980 initial goal, declare "that" only as Pure intro (only for single
  5981 steps); the "that" rule assumption may now be involved in implicit
  5982 finishing, thus ".." becomes a feasible for trivial obtains;
  5983 
  5984 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5985 instance proofs may be performed by "..";
  5986 
  5987 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5988 statements as well;
  5989 
  5990 * Pure: more robust selection of calculational rules;
  5991 
  5992 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5993 rule (as well as the assumption rule);
  5994 
  5995 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5996 lemmas, using the graph browser tool;
  5997 
  5998 * Pure: predict failure of "show" in interactive mode;
  5999 
  6000 * Pure: 'thms_containing' now takes actual terms as arguments;
  6001 
  6002 * HOL: improved method 'induct' --- now handles non-atomic goals
  6003 (potential INCOMPATIBILITY); tuned error handling;
  6004 
  6005 * HOL: cases and induct rules now provide explicit hints about the
  6006 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6007 any remaining facts are inserted into the goal verbatim;
  6008 
  6009 * HOL: local contexts (aka cases) may now contain term bindings as
  6010 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6011 the result to be shown in each case;
  6012 
  6013 * HOL: added 'recdef_tc' command;
  6014 
  6015 * isatool convert assists in eliminating legacy ML scripts;
  6016 
  6017 
  6018 *** HOL ***
  6019 
  6020 * HOL/Library: a collection of generic theories to be used together
  6021 with main HOL; the theory loader path already includes this directory
  6022 by default; the following existing theories have been moved here:
  6023 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6024 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6025 
  6026 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6027 modelling and verification task performed in Isabelle/HOL +
  6028 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6029 
  6030 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6031 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6032 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6033 'domain', this makes the theory consistent with mathematical
  6034 literature;
  6035 
  6036 * HOL basics: added overloaded operations "inverse" and "divide"
  6037 (infix "/"), syntax for generic "abs" operation, generic summation
  6038 operator \<Sum>;
  6039 
  6040 * HOL/typedef: simplified package, provide more useful rules (see also
  6041 HOL/subset.thy);
  6042 
  6043 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6044 now expressed as a proper nested rule (old-style tactic scripts may
  6045 require atomize_strip_tac to cope with non-atomic premises);
  6046 
  6047 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6048 to "split_conv" (old name still available for compatibility);
  6049 
  6050 * HOL: improved concrete syntax for strings (e.g. allows translation
  6051 rules with string literals);
  6052 
  6053 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6054  and Fleuriot's mechanization of analysis, including the transcendental
  6055  functions for the reals;
  6056 
  6057 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6058 
  6059 
  6060 *** CTT ***
  6061 
  6062 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6063 "lam" is displayed as TWO lambda-symbols
  6064 
  6065 * CTT: theory Main now available, containing everything (that is, Bool
  6066 and Arith);
  6067 
  6068 
  6069 *** General ***
  6070 
  6071 * Pure: the Simplifier has been implemented properly as a derived rule
  6072 outside of the actual kernel (at last!); the overall performance
  6073 penalty in practical applications is about 50%, while reliability of
  6074 the Isabelle inference kernel has been greatly improved;
  6075 
  6076 * print modes "brackets" and "no_brackets" control output of nested =>
  6077 (types) and ==> (props); the default behaviour is "brackets";
  6078 
  6079 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6080 as assumptions as well;
  6081 
  6082 * system: support Poly/ML 4.0;
  6083 
  6084 * system: isatool install handles KDE version 1 or 2;
  6085 
  6086 
  6087 
  6088 New in Isabelle99-1 (October 2000)
  6089 ----------------------------------
  6090 
  6091 *** Overview of INCOMPATIBILITIES ***
  6092 
  6093 * HOL: simplification of natural numbers is much changed; to partly
  6094 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6095 issue the following ML commands:
  6096 
  6097   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6098   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6099 
  6100 * HOL: simplification no longer dives into case-expressions; this is
  6101 controlled by "t.weak_case_cong" for each datatype t;
  6102 
  6103 * HOL: nat_less_induct renamed to less_induct;
  6104 
  6105 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6106 fixsome to patch .thy and .ML sources automatically;
  6107 
  6108   select_equality  -> some_equality
  6109   select_eq_Ex     -> some_eq_ex
  6110   selectI2EX       -> someI2_ex
  6111   selectI2         -> someI2
  6112   selectI          -> someI
  6113   select1_equality -> some1_equality
  6114   Eps_sym_eq       -> some_sym_eq_trivial
  6115   Eps_eq           -> some_eq_trivial
  6116 
  6117 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6118 
  6119 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6120 instead);
  6121 
  6122 * HOL: the recursion equations generated by 'recdef' are now called
  6123 f.simps instead of f.rules;
  6124 
  6125 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6126 
  6127 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6128 sometimes be needed;
  6129 
  6130 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6131 
  6132 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6133 
  6134 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6135 product is now "<*>" instead of "Times"; the lexicographic product is
  6136 now "<*lex*>" instead of "**";
  6137 
  6138 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6139 of main HOL, but was unused); better use HOL's datatype package;
  6140 
  6141 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6142 the old syntax may be recovered as follows:
  6143 
  6144   syntax (symbols)
  6145     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6146       (infixl "\\<oplus>" 100)
  6147 
  6148 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6149 
  6150 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6151 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6152 internally;
  6153 
  6154 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6155 changed from A/r to A//r;
  6156 
  6157 * ZF: new treatment of arithmetic (nat & int) may break some old
  6158 proofs;
  6159 
  6160 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6161 rulify -> rule_format, elimify -> elim_format, ...);
  6162 
  6163 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6164 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6165 should have to change intro!! to intro? only); replaced "delrule" by
  6166 "rule del";
  6167 
  6168 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6169 
  6170 * Provers: strengthened force_tac by using new first_best_tac;
  6171 
  6172 * LaTeX document preparation: several changes of isabelle.sty (see
  6173 lib/texinputs);
  6174 
  6175 
  6176 *** Document preparation ***
  6177 
  6178 * formal comments (text blocks etc.) in new-style theories may now
  6179 contain antiquotations of thm/prop/term/typ/text to be presented
  6180 according to latex print mode; concrete syntax is like this:
  6181 @{term[show_types] "f(x) = a + x"};
  6182 
  6183 * isatool mkdir provides easy setup of Isabelle session directories,
  6184 including proper document sources;
  6185 
  6186 * generated LaTeX sources are now deleted after successful run
  6187 (isatool document -c); may retain a copy somewhere else via -D option
  6188 of isatool usedir;
  6189 
  6190 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6191 style files, achieving self-contained LaTeX sources and simplifying
  6192 LaTeX debugging;
  6193 
  6194 * old-style theories now produce (crude) LaTeX output as well;
  6195 
  6196 * browser info session directories are now self-contained (may be put
  6197 on WWW server seperately); improved graphs of nested sessions; removed
  6198 graph for 'all sessions';
  6199 
  6200 * several improvements in isabelle style files; \isabellestyle{it}
  6201 produces fake math mode output; \isamarkupheader is now \section by
  6202 default; see lib/texinputs/isabelle.sty etc.;
  6203 
  6204 
  6205 *** Isar ***
  6206 
  6207 * Isar/Pure: local results and corresponding term bindings are now
  6208 subject to Hindley-Milner polymorphism (similar to ML); this
  6209 accommodates incremental type-inference very nicely;
  6210 
  6211 * Isar/Pure: new derived language element 'obtain' supports
  6212 generalized existence reasoning;
  6213 
  6214 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6215 support accumulation of results, without applying any rules yet;
  6216 useful to collect intermediate results without explicit name
  6217 references, and for use with transitivity rules with more than 2
  6218 premises;
  6219 
  6220 * Isar/Pure: scalable support for case-analysis type proofs: new
  6221 'case' language element refers to local contexts symbolically, as
  6222 produced by certain proof methods; internally, case names are attached
  6223 to theorems as "tags";
  6224 
  6225 * Isar/Pure: theory command 'hide' removes declarations from
  6226 class/type/const name spaces;
  6227 
  6228 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6229 indicate potential overloading;
  6230 
  6231 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6232 
  6233 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6234 "{a,b,c}" instead of {a,b,c};
  6235 
  6236 * Isar/Pure now provides its own version of intro/elim/dest
  6237 attributes; useful for building new logics, but beware of confusion
  6238 with the version