NEWS
author krauss
Mon Jul 27 21:47:41 2009 +0200 (2009-07-27)
changeset 32235 8f9b8d14fc9f
parent 32217 420108dd7dfe
child 32264 0be31453f698
permissions -rw-r--r--
"more standard" argument order of relation composition (op O)
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
    10 one backslash should be used, even in ML sources.
    11 
    12 
    13 *** Pure ***
    14 
    15 * On instantiation of classes, remaining undefined class parameters
    16 are formally declared.  INCOMPATIBILITY.
    17 
    18 
    19 *** HOL ***
    20 
    21 * More convenient names for set intersection and union.  INCOMPATIBILITY:
    22 
    23     Set.Int ~>  Set.inter
    24     Set.Un ~>   Set.union
    25 
    26 * Code generator attributes follow the usual underscore convention:
    27     code_unfold     replaces    code unfold
    28     code_post       replaces    code post
    29     etc.
    30   INCOMPATIBILITY.
    31 
    32 * New quickcheck implementation using new code generator.
    33 
    34 * New class "boolean_algebra".
    35 
    36 * Refinements to lattices classes:
    37   - added boolean_algebra type class
    38   - less default intro/elim rules in locale variant, more default
    39     intro/elim rules in class variant: more uniformity
    40   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with le_inf_iff
    41   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and sup_aci)
    42   - renamed ACI to inf_sup_aci
    43   - class "complete_lattice" moved to separate theory "complete_lattice";
    44     corresponding constants renamed:
    45     
    46     Set.Inf ~>      Complete_Lattice.Inf
    47     Set.Sup ~>      Complete_Lattice.Sup
    48     Set.INFI ~>     Complete_Lattice.INFI
    49     Set.SUPR ~>     Complete_Lattice.SUPR
    50     Set.Inter ~>    Complete_Lattice.Inter
    51     Set.Union ~>    Complete_Lattice.Union
    52     Set.INTER ~>    Complete_Lattice.INTER
    53     Set.UNION ~>    Complete_Lattice.UNION
    54 
    55   INCOMPATIBILITY.
    56 
    57 * Class semiring_div requires superclass no_zero_divisors and proof of
    58 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
    59 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
    60 generalized to class semiring_div, subsuming former theorems
    61 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
    62 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
    63 INCOMPATIBILITY.
    64 
    65 * Power operations on relations and functions are now one dedicate
    66 constant compow with infix syntax "^^".  Power operations on
    67 multiplicative monoids retains syntax "^" and is now defined generic
    68 in class power.  INCOMPATIBILITY.
    69 
    70 * Relation composition "R O S" now has a "more standard" argument order,
    71 i.e., "R O S = {(x,z). EX y. (x,y) : R & (y,z) : S }".
    72 INCOMPATIBILITY: Rewrite propositions with "S O R" --> "R O S". Proofs
    73 may occationally break, since the O_assoc rule was not rewritten like this.
    74 Fix using O_assoc[symmetric].
    75 The same applies to the curried version "R OO S".
    76 
    77 * GCD now has functions Gcd/GCD and Lcm/LCM for the gcd and lcm of finite and
    78 infinite sets. It is shown that they form a complete lattice.
    79 
    80 * ML antiquotation @{code_datatype} inserts definition of a datatype
    81 generated by the code generator; see Predicate.thy for an example.
    82 
    83 * New method "linarith" invokes existing linear arithmetic decision
    84 procedure only.
    85 
    86 * Implementation of quickcheck using generic code generator; default
    87 generators are provided for all suitable HOL types, records and
    88 datatypes.
    89 
    90 * Constants Set.Pow and Set.image now with authentic syntax;
    91 object-logic definitions Set.Pow_def and Set.image_def.
    92 INCOMPATIBILITY.
    93 
    94 * Renamed theorems:
    95 Suc_eq_add_numeral_1 -> Suc_eq_plus1
    96 Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
    97 Suc_plus1 -> Suc_eq_plus1
    98 
    99 * New sledgehammer option "Full Types" in Proof General settings menu.
   100 Causes full type information to be output to the ATPs.  This slows
   101 ATPs down considerably but eliminates a source of unsound "proofs"
   102 that fail later.
   103 
   104 * Discontinued ancient tradition to suffix certain ML module names
   105 with "_package", e.g.:
   106 
   107     DatatypePackage ~> Datatype
   108     InductivePackage ~> Inductive
   109 
   110     etc.
   111 
   112 INCOMPATIBILITY.
   113 
   114 * NewNumberTheory: Jeremy Avigad's new version of part of
   115 NumberTheory.  If possible, use NewNumberTheory, not NumberTheory.
   116 
   117 * Simplified interfaces of datatype module.  INCOMPATIBILITY.
   118 
   119 * Abbreviation "arbitrary" of "undefined" has disappeared; use
   120 "undefined" directly.  INCOMPATIBILITY.
   121 
   122 * New evaluator "approximate" approximates an real valued term using
   123 the same method as the approximation method.
   124 
   125 * Method "approximate" supports now arithmetic expressions as
   126 boundaries of intervals and implements interval splitting and Taylor
   127 series expansion.
   128 
   129 * Changed DERIV_intros to a dynamic fact (via Named_Thms).  Each of
   130 the theorems in DERIV_intros assumes composition with an additional
   131 function and matches a variable to the derivative, which has to be
   132 solved by the simplifier.  Hence (auto intro!: DERIV_intros) computes
   133 the derivative of most elementary terms.
   134 
   135 * Maclauren.DERIV_tac and Maclauren.deriv_tac was removed, they are
   136 replaced by: (auto intro!: DERIV_intros).  INCOMPATIBILITY.
   137 
   138 
   139 *** ML ***
   140 
   141 * Tactical FOCUS is similar to SUBPROOF, but allows the body tactic to
   142 introduce new subgoals and schematic variables.  FOCUS_PARAMS is
   143 similar, but focuses on the parameter prefix only, leaving subgoal
   144 premises unchanged.
   145 
   146 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
   147 functors have their own ML name space there is no point to mark them
   148 separately.)  Minor INCOMPATIBILITY.
   149 
   150 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
   151 
   152 * Eliminated old Attrib.add_attributes, Method.add_methods and related
   153 cominators for "args".  INCOMPATIBILITY, need to use simplified
   154 Attrib/Method.setup introduced in Isabelle2009.
   155 
   156 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
   157 back on global_simpset_of, global_claset_of, global_clasimpset_of as
   158 last resort.  INCOMPATIBILITY.
   159 
   160 * Display.pretty_thm now requires a proper context (cf. former
   161 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
   162 or even Display.pretty_thm_without_context as last resort.
   163 INCOMPATIBILITY.
   164 
   165 
   166 *** System ***
   167 
   168 * Discontinued support for Poly/ML 4.x versions.
   169 
   170 * Removed "compress" option from isabelle-process and isabelle usedir;
   171 this is always enabled.
   172 
   173 * More fine-grained control of proof parallelism, cf.
   174 Goal.parallel_proofs in ML and usedir option -q LEVEL.
   175 
   176 
   177 
   178 New in Isabelle2009 (April 2009)
   179 --------------------------------
   180 
   181 *** General ***
   182 
   183 * Simplified main Isabelle executables, with less surprises on
   184 case-insensitive file-systems (such as Mac OS).
   185 
   186   - The main Isabelle tool wrapper is now called "isabelle" instead of
   187     "isatool."
   188 
   189   - The former "isabelle" alias for "isabelle-process" has been
   190     removed (should rarely occur to regular users).
   191 
   192   - The former "isabelle-interface" and its alias "Isabelle" have been
   193     removed (interfaces are now regular Isabelle tools).
   194 
   195 Within scripts and make files, the Isabelle environment variables
   196 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
   197 respectively.  (The latter are still available as legacy feature.)
   198 
   199 The old isabelle-interface wrapper could react in confusing ways if
   200 the interface was uninstalled or changed otherwise.  Individual
   201 interface tool configuration is now more explicit, see also the
   202 Isabelle system manual.  In particular, Proof General is now available
   203 via "isabelle emacs".
   204 
   205 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
   206 purge installed copies of Isabelle executables and re-run "isabelle
   207 install -p ...", or use symlinks.
   208 
   209 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
   210 old ~/isabelle, which was slightly non-standard and apt to cause
   211 surprises on case-insensitive file-systems (such as Mac OS).
   212 
   213 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
   214 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
   215 care is required when using older releases of Isabelle.  Note that
   216 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
   217 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
   218 
   219 * Proofs of fully specified statements are run in parallel on
   220 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
   221 a regular 4-core machine, if the initial heap space is made reasonably
   222 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
   223 
   224 * The main reference manuals ("isar-ref", "implementation", and
   225 "system") have been updated and extended.  Formally checked references
   226 as hyperlinks are now available uniformly.
   227 
   228 
   229 *** Pure ***
   230 
   231 * Complete re-implementation of locales.  INCOMPATIBILITY in several
   232 respects.  The most important changes are listed below.  See the
   233 Tutorial on Locales ("locales" manual) for details.
   234 
   235 - In locale expressions, instantiation replaces renaming.  Parameters
   236 must be declared in a for clause.  To aid compatibility with previous
   237 parameter inheritance, in locale declarations, parameters that are not
   238 'touched' (instantiation position "_" or omitted) are implicitly added
   239 with their syntax at the beginning of the for clause.
   240 
   241 - Syntax from abbreviations and definitions in locales is available in
   242 locale expressions and context elements.  The latter is particularly
   243 useful in locale declarations.
   244 
   245 - More flexible mechanisms to qualify names generated by locale
   246 expressions.  Qualifiers (prefixes) may be specified in locale
   247 expressions, and can be marked as mandatory (syntax: "name!:") or
   248 optional (syntax "name?:").  The default depends for plain "name:"
   249 depends on the situation where a locale expression is used: in
   250 commands 'locale' and 'sublocale' prefixes are optional, in
   251 'interpretation' and 'interpret' prefixes are mandatory.  The old
   252 implicit qualifiers derived from the parameter names of a locale are
   253 no longer generated.
   254 
   255 - Command "sublocale l < e" replaces "interpretation l < e".  The
   256 instantiation clause in "interpretation" and "interpret" (square
   257 brackets) is no longer available.  Use locale expressions.
   258 
   259 - When converting proof scripts, mandatory qualifiers in
   260 'interpretation' and 'interpret' should be retained by default, even
   261 if this is an INCOMPATIBILITY compared to former behavior.  In the
   262 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
   263 in locale expressions range over a single locale instance only.
   264 
   265 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
   266 In existing theorem specifications replace the includes element by the
   267 respective context elements of the included locale, omitting those
   268 that are already present in the theorem specification.  Multiple
   269 assume elements of a locale should be replaced by a single one
   270 involving the locale predicate.  In the proof body, declarations (most
   271 notably theorems) may be regained by interpreting the respective
   272 locales in the proof context as required (command "interpret").
   273 
   274 If using "includes" in replacement of a target solely because the
   275 parameter types in the theorem are not as general as in the target,
   276 consider declaring a new locale with additional type constraints on
   277 the parameters (context element "constrains").
   278 
   279 - Discontinued "locale (open)".  INCOMPATIBILITY.
   280 
   281 - Locale interpretation commands no longer attempt to simplify goal.
   282 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
   283 methods intro_locales and unfold_locales to clarify.
   284 
   285 - Locale interpretation commands no longer accept interpretation
   286 attributes.  INCOMPATIBILITY.
   287 
   288 * Class declaration: so-called "base sort" must not be given in import
   289 list any longer, but is inferred from the specification.  Particularly
   290 in HOL, write
   291 
   292     class foo = ...
   293 
   294 instead of
   295 
   296     class foo = type + ...
   297 
   298 * Class target: global versions of theorems stemming do not carry a
   299 parameter prefix any longer.  INCOMPATIBILITY.
   300 
   301 * Class 'instance' command no longer accepts attached definitions.
   302 INCOMPATIBILITY, use proper 'instantiation' target instead.
   303 
   304 * Recovered hiding of consts, which was accidentally broken in
   305 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
   306 makes c inaccessible; consider using ``hide (open) const c'' instead.
   307 
   308 * Slightly more coherent Pure syntax, with updated documentation in
   309 isar-ref manual.  Removed locales meta_term_syntax and
   310 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
   311 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
   312 directly in regular applications.
   313 
   314 * There is a new syntactic category "float_const" for signed decimal
   315 fractions (e.g. 123.45 or -123.45).
   316 
   317 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
   318 interface with 'setup' command instead.
   319 
   320 * Command 'local_setup' is similar to 'setup', but operates on a local
   321 theory context.
   322 
   323 * The 'axiomatization' command now only works within a global theory
   324 context.  INCOMPATIBILITY.
   325 
   326 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
   327 hypotheses.  Sorts required in the course of reasoning need to be
   328 covered by the constraints in the initial statement, completed by the
   329 type instance information of the background theory.  Non-trivial sort
   330 hypotheses, which rarely occur in practice, may be specified via
   331 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
   332 
   333   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
   334 
   335 The result contains an implicit sort hypotheses as before --
   336 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
   337 normalization.
   338 
   339 * Generalized Isar history, with support for linear undo, direct state
   340 addressing etc.
   341 
   342 * Changed defaults for unify configuration options:
   343 
   344   unify_trace_bound = 50 (formerly 25)
   345   unify_search_bound = 60 (formerly 30)
   346 
   347 * Different bookkeeping for code equations (INCOMPATIBILITY):
   348 
   349   a) On theory merge, the last set of code equations for a particular
   350      constant is taken (in accordance with the policy applied by other
   351      parts of the code generator framework).
   352 
   353   b) Code equations stemming from explicit declarations (e.g. code
   354      attribute) gain priority over default code equations stemming
   355      from definition, primrec, fun etc.
   356 
   357 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
   358 
   359 * Unified theorem tables for both code generators.  Thus [code
   360 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
   361 
   362 * Command 'find_consts' searches for constants based on type and name
   363 patterns, e.g.
   364 
   365     find_consts "_ => bool"
   366 
   367 By default, matching is against subtypes, but it may be restricted to
   368 the whole type.  Searching by name is possible.  Multiple queries are
   369 conjunctive and queries may be negated by prefixing them with a
   370 hyphen:
   371 
   372     find_consts strict: "_ => bool" name: "Int" -"int => int"
   373 
   374 * New 'find_theorems' criterion "solves" matches theorems that
   375 directly solve the current goal (modulo higher-order unification).
   376 
   377 * Auto solve feature for main theorem statements: whenever a new goal
   378 is stated, "find_theorems solves" is called; any theorems that could
   379 solve the lemma directly are listed as part of the goal state.
   380 Cf. associated options in Proof General Isabelle settings menu,
   381 enabled by default, with reasonable timeout for pathological cases of
   382 higher-order unification.
   383 
   384 
   385 *** Document preparation ***
   386 
   387 * Antiquotation @{lemma} now imitates a regular terminal proof,
   388 demanding keyword 'by' and supporting the full method expression
   389 syntax just like the Isar command 'by'.
   390 
   391 
   392 *** HOL ***
   393 
   394 * Integrated main parts of former image HOL-Complex with HOL.  Entry
   395 points Main and Complex_Main remain as before.
   396 
   397 * Logic image HOL-Plain provides a minimal HOL with the most important
   398 tools available (inductive, datatype, primrec, ...).  This facilitates
   399 experimentation and tool development.  Note that user applications
   400 (and library theories) should never refer to anything below theory
   401 Main, as before.
   402 
   403 * Logic image HOL-Main stops at theory Main, and thus facilitates
   404 experimentation due to shorter build times.
   405 
   406 * Logic image HOL-NSA contains theories of nonstandard analysis which
   407 were previously part of former HOL-Complex.  Entry point Hyperreal
   408 remains valid, but theories formerly using Complex_Main should now use
   409 new entry point Hypercomplex.
   410 
   411 * Generic ATP manager for Sledgehammer, based on ML threads instead of
   412 Posix processes.  Avoids potentially expensive forking of the ML
   413 process.  New thread-based implementation also works on non-Unix
   414 platforms (Cygwin).  Provers are no longer hardwired, but defined
   415 within the theory via plain ML wrapper functions.  Basic Sledgehammer
   416 commands are covered in the isar-ref manual.
   417 
   418 * Wrapper scripts for remote SystemOnTPTP service allows to use
   419 sledgehammer without local ATP installation (Vampire etc.). Other
   420 provers may be included via suitable ML wrappers, see also
   421 src/HOL/ATP_Linkup.thy.
   422 
   423 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
   424 menu.
   425 
   426 * The metis method no longer fails because the theorem is too trivial
   427 (contains the empty clause).
   428 
   429 * The metis method now fails in the usual manner, rather than raising
   430 an exception, if it determines that it cannot prove the theorem.
   431 
   432 * Method "coherent" implements a prover for coherent logic (see also
   433 src/Tools/coherent.ML).
   434 
   435 * Constants "undefined" and "default" replace "arbitrary".  Usually
   436 "undefined" is the right choice to replace "arbitrary", though
   437 logically there is no difference.  INCOMPATIBILITY.
   438 
   439 * Command "value" now integrates different evaluation mechanisms.  The
   440 result of the first successful evaluation mechanism is printed.  In
   441 square brackets a particular named evaluation mechanisms may be
   442 specified (currently, [SML], [code] or [nbe]).  See further
   443 src/HOL/ex/Eval_Examples.thy.
   444 
   445 * Normalization by evaluation now allows non-leftlinear equations.
   446 Declare with attribute [code nbe].
   447 
   448 * Methods "case_tac" and "induct_tac" now refer to the very same rules
   449 as the structured Isar versions "cases" and "induct", cf. the
   450 corresponding "cases" and "induct" attributes.  Mutual induction rules
   451 are now presented as a list of individual projections
   452 (e.g. foo_bar.inducts for types foo and bar); the old format with
   453 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
   454 rare situations a different rule is selected --- notably nested tuple
   455 elimination instead of former prod.exhaust: use explicit (case_tac t
   456 rule: prod.exhaust) here.
   457 
   458 * Attributes "cases", "induct", "coinduct" support "del" option.
   459 
   460 * Removed fact "case_split_thm", which duplicates "case_split".
   461 
   462 * The option datatype has been moved to a new theory Option.  Renamed
   463 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
   464 
   465 * New predicate "strict_mono" classifies strict functions on partial
   466 orders.  With strict functions on linear orders, reasoning about
   467 (in)equalities is facilitated by theorems "strict_mono_eq",
   468 "strict_mono_less_eq" and "strict_mono_less".
   469 
   470 * Some set operations are now proper qualified constants with
   471 authentic syntax.  INCOMPATIBILITY:
   472 
   473     op Int ~>   Set.Int
   474     op Un ~>    Set.Un
   475     INTER ~>    Set.INTER
   476     UNION ~>    Set.UNION
   477     Inter ~>    Set.Inter
   478     Union ~>    Set.Union
   479     {} ~>       Set.empty
   480     UNIV ~>     Set.UNIV
   481 
   482 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
   483 theory Set.
   484 
   485 * Auxiliary class "itself" has disappeared -- classes without any
   486 parameter are treated as expected by the 'class' command.
   487 
   488 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
   489 
   490 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
   491 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
   492 
   493 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
   494 method "approximation".  It proves formulas on real values by using
   495 interval arithmetic.  In the formulas are also the transcendental
   496 functions sin, cos, tan, atan, ln, exp and the constant pi are
   497 allowed. For examples see
   498 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
   499 
   500 * Theory "Reflection" now resides in HOL/Library.
   501 
   502 * Entry point to Word library now simply named "Word".
   503 INCOMPATIBILITY.
   504 
   505 * Made source layout more coherent with logical distribution
   506 structure:
   507 
   508     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
   509     src/HOL/Library/Code_Message.thy ~> src/HOL/
   510     src/HOL/Library/GCD.thy ~> src/HOL/
   511     src/HOL/Library/Order_Relation.thy ~> src/HOL/
   512     src/HOL/Library/Parity.thy ~> src/HOL/
   513     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
   514     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
   515     src/HOL/Real/Lubs.thy ~> src/HOL/
   516     src/HOL/Real/PReal.thy ~> src/HOL/
   517     src/HOL/Real/Rational.thy ~> src/HOL/
   518     src/HOL/Real/RComplete.thy ~> src/HOL/
   519     src/HOL/Real/RealDef.thy ~> src/HOL/
   520     src/HOL/Real/RealPow.thy ~> src/HOL/
   521     src/HOL/Real/Real.thy ~> src/HOL/
   522     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
   523     src/HOL/Complex/Complex.thy ~> src/HOL/
   524     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
   525     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
   526     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
   527     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
   528     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
   529     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
   530     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
   531     src/HOL/Hyperreal/Log.thy ~> src/HOL/
   532     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
   533     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
   534     src/HOL/Hyperreal/Series.thy ~> src/HOL/
   535     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
   536     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
   537     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
   538     src/HOL/Real/Float ~> src/HOL/Library/
   539     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
   540     src/HOL/Real/RealVector.thy ~> src/HOL/
   541 
   542     src/HOL/arith_data.ML ~> src/HOL/Tools
   543     src/HOL/hologic.ML ~> src/HOL/Tools
   544     src/HOL/simpdata.ML ~> src/HOL/Tools
   545     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
   546     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
   547     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
   548     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
   549     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
   550     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
   551     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
   552 
   553     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
   554     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
   555     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
   556     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
   557     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
   558     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
   559 
   560 * If methods "eval" and "evaluation" encounter a structured proof
   561 state with !!/==>, only the conclusion is evaluated to True (if
   562 possible), avoiding strange error messages.
   563 
   564 * Method "sizechange" automates termination proofs using (a
   565 modification of) the size-change principle.  Requires SAT solver.  See
   566 src/HOL/ex/Termination.thy for examples.
   567 
   568 * Simplifier: simproc for let expressions now unfolds if bound
   569 variable occurs at most once in let expression body.  INCOMPATIBILITY.
   570 
   571 * Method "arith": Linear arithmetic now ignores all inequalities when
   572 fast_arith_neq_limit is exceeded, instead of giving up entirely.
   573 
   574 * New attribute "arith" for facts that should always be used
   575 automatically by arithmetic. It is intended to be used locally in
   576 proofs, e.g.
   577 
   578   assumes [arith]: "x > 0"
   579 
   580 Global usage is discouraged because of possible performance impact.
   581 
   582 * New classes "top" and "bot" with corresponding operations "top" and
   583 "bot" in theory Orderings; instantiation of class "complete_lattice"
   584 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
   585 
   586 * Changed definition lemma "less_fun_def" in order to provide an
   587 instance for preorders on functions; use lemma "less_le" instead.
   588 INCOMPATIBILITY.
   589 
   590 * Theory Orderings: class "wellorder" moved here, with explicit
   591 induction rule "less_induct" as assumption.  For instantiation of
   592 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
   593 INCOMPATIBILITY.
   594 
   595 * Theory Orderings: added class "preorder" as superclass of "order".
   596 INCOMPATIBILITY: Instantiation proofs for order, linorder
   597 etc. slightly changed.  Some theorems named order_class.* now named
   598 preorder_class.*.
   599 
   600 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
   601 "diag" to "Id_on".
   602 
   603 * Theory Finite_Set: added a new fold combinator of type
   604 
   605   ('a => 'b => 'b) => 'b => 'a set => 'b
   606 
   607 Occasionally this is more convenient than the old fold combinator
   608 which is now defined in terms of the new one and renamed to
   609 fold_image.
   610 
   611 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
   612 and "ring_simps" have been replaced by "algebra_simps" (which can be
   613 extended with further lemmas!).  At the moment both still exist but
   614 the former will disappear at some point.
   615 
   616 * Theory Power: Lemma power_Suc is now declared as a simp rule in
   617 class recpower.  Type-specific simp rules for various recpower types
   618 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
   619 
   620 rat_power_0    -> power_0
   621 rat_power_Suc  -> power_Suc
   622 realpow_0      -> power_0
   623 realpow_Suc    -> power_Suc
   624 complexpow_0   -> power_0
   625 complexpow_Suc -> power_Suc
   626 power_poly_0   -> power_0
   627 power_poly_Suc -> power_Suc
   628 
   629 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
   630 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
   631 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
   632 of lemmas from Divides has been generalized from nat to class
   633 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
   634 renames resulting from duplicate elimination:
   635 
   636     dvd_def_mod ~>          dvd_eq_mod_eq_0
   637     zero_dvd_iff ~>         dvd_0_left_iff
   638     dvd_0 ~>                dvd_0_right
   639     DIVISION_BY_ZERO_DIV ~> div_by_0
   640     DIVISION_BY_ZERO_MOD ~> mod_by_0
   641     mult_div ~>             div_mult_self2_is_id
   642     mult_mod ~>             mod_mult_self2_is_0
   643 
   644 * Theory IntDiv: removed many lemmas that are instances of class-based
   645 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
   646 rename old lemmas as follows:
   647 
   648 dvd_diff               -> nat_dvd_diff
   649 dvd_zminus_iff         -> dvd_minus_iff
   650 mod_add1_eq            -> mod_add_eq
   651 mod_mult1_eq           -> mod_mult_right_eq
   652 mod_mult1_eq'          -> mod_mult_left_eq
   653 mod_mult_distrib_mod   -> mod_mult_eq
   654 nat_mod_add_left_eq    -> mod_add_left_eq
   655 nat_mod_add_right_eq   -> mod_add_right_eq
   656 nat_mod_div_trivial    -> mod_div_trivial
   657 nat_mod_mod_trivial    -> mod_mod_trivial
   658 zdiv_zadd_self1        -> div_add_self1
   659 zdiv_zadd_self2        -> div_add_self2
   660 zdiv_zmult_self1       -> div_mult_self2_is_id
   661 zdiv_zmult_self2       -> div_mult_self1_is_id
   662 zdvd_triv_left         -> dvd_triv_left
   663 zdvd_triv_right        -> dvd_triv_right
   664 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
   665 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
   666 zmod_zadd_left_eq      -> mod_add_left_eq
   667 zmod_zadd_right_eq     -> mod_add_right_eq
   668 zmod_zadd_self1        -> mod_add_self1
   669 zmod_zadd_self2        -> mod_add_self2
   670 zmod_zadd1_eq          -> mod_add_eq
   671 zmod_zdiff1_eq         -> mod_diff_eq
   672 zmod_zdvd_zmod         -> mod_mod_cancel
   673 zmod_zmod_cancel       -> mod_mod_cancel
   674 zmod_zmult_self1       -> mod_mult_self2_is_0
   675 zmod_zmult_self2       -> mod_mult_self1_is_0
   676 zmod_1                 -> mod_by_1
   677 zdiv_1                 -> div_by_1
   678 zdvd_abs1              -> abs_dvd_iff
   679 zdvd_abs2              -> dvd_abs_iff
   680 zdvd_refl              -> dvd_refl
   681 zdvd_trans             -> dvd_trans
   682 zdvd_zadd              -> dvd_add
   683 zdvd_zdiff             -> dvd_diff
   684 zdvd_zminus_iff        -> dvd_minus_iff
   685 zdvd_zminus2_iff       -> minus_dvd_iff
   686 zdvd_zmultD            -> dvd_mult_right
   687 zdvd_zmultD2           -> dvd_mult_left
   688 zdvd_zmult_mono        -> mult_dvd_mono
   689 zdvd_0_right           -> dvd_0_right
   690 zdvd_0_left            -> dvd_0_left_iff
   691 zdvd_1_left            -> one_dvd
   692 zminus_dvd_iff         -> minus_dvd_iff
   693 
   694 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
   695 
   696 * The real numbers offer decimal input syntax: 12.34 is translated
   697 into 1234/10^2. This translation is not reversed upon output.
   698 
   699 * Theory Library/Polynomial defines an abstract type 'a poly of
   700 univariate polynomials with coefficients of type 'a.  In addition to
   701 the standard ring operations, it also supports div and mod.  Code
   702 generation is also supported, using list-style constructors.
   703 
   704 * Theory Library/Inner_Product defines a class of real_inner for real
   705 inner product spaces, with an overloaded operation inner :: 'a => 'a
   706 => real.  Class real_inner is a subclass of real_normed_vector from
   707 theory RealVector.
   708 
   709 * Theory Library/Product_Vector provides instances for the product
   710 type 'a * 'b of several classes from RealVector and Inner_Product.
   711 Definitions of addition, subtraction, scalar multiplication, norms,
   712 and inner products are included.
   713 
   714 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
   715 addition to the field operations, numerals and case syntax are also
   716 supported.
   717 
   718 * Theory Library/Diagonalize provides constructive version of Cantor's
   719 first diagonalization argument.
   720 
   721 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
   722 zlcm (for int); carried together from various gcd/lcm developements in
   723 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
   724 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
   725 may recover tupled syntax as follows:
   726 
   727     hide (open) const gcd
   728     abbreviation gcd where
   729       "gcd == (%(a, b). GCD.gcd a b)"
   730     notation (output)
   731       GCD.gcd ("gcd '(_, _')")
   732 
   733 The same works for lcm, zgcd, zlcm.
   734 
   735 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
   736 instantiations for algebraic structures.  Removed some duplicate
   737 theorems.  Changes in simp rules.  INCOMPATIBILITY.
   738 
   739 * ML antiquotation @{code} takes a constant as argument and generates
   740 corresponding code in background and inserts name of the corresponding
   741 resulting ML value/function/datatype constructor binding in place.
   742 All occurrences of @{code} with a single ML block are generated
   743 simultaneously.  Provides a generic and safe interface for
   744 instrumentalizing code generation.  See
   745 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
   746 In future you ought to refrain from ad-hoc compiling generated SML
   747 code on the ML toplevel.  Note that (for technical reasons) @{code}
   748 cannot refer to constants for which user-defined serializations are
   749 set.  Refer to the corresponding ML counterpart directly in that
   750 cases.
   751 
   752 * Command 'rep_datatype': instead of theorem names the command now
   753 takes a list of terms denoting the constructors of the type to be
   754 represented as datatype.  The characteristic theorems have to be
   755 proven.  INCOMPATIBILITY.  Also observe that the following theorems
   756 have disappeared in favour of existing ones:
   757 
   758     unit_induct                 ~> unit.induct
   759     prod_induct                 ~> prod.induct
   760     sum_induct                  ~> sum.induct
   761     Suc_Suc_eq                  ~> nat.inject
   762     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
   763 
   764 
   765 *** HOL-Algebra ***
   766 
   767 * New locales for orders and lattices where the equivalence relation
   768 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
   769 locales use a record structure with field eq for the equivalence.
   770 
   771 * New theory of factorial domains.
   772 
   773 * Units_l_inv and Units_r_inv are now simp rules by default.
   774 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
   775 and/or r_inv will now also require deletion of these lemmas.
   776 
   777 * Renamed the following theorems, INCOMPATIBILITY:
   778 
   779 UpperD ~> Upper_memD
   780 LowerD ~> Lower_memD
   781 least_carrier ~> least_closed
   782 greatest_carrier ~> greatest_closed
   783 greatest_Lower_above ~> greatest_Lower_below
   784 one_zero ~> carrier_one_zero
   785 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
   786 
   787 
   788 *** HOL-Nominal ***
   789 
   790 * Nominal datatypes can now contain type-variables.
   791 
   792 * Commands 'nominal_inductive' and 'equivariance' work with local
   793 theory targets.
   794 
   795 * Nominal primrec can now works with local theory targets and its
   796 specification syntax now conforms to the general format as seen in
   797 'inductive' etc.
   798 
   799 * Method "perm_simp" honours the standard simplifier attributes
   800 (no_asm), (no_asm_use) etc.
   801 
   802 * The new predicate #* is defined like freshness, except that on the
   803 left hand side can be a set or list of atoms.
   804 
   805 * Experimental command 'nominal_inductive2' derives strong induction
   806 principles for inductive definitions.  In contrast to
   807 'nominal_inductive', which can only deal with a fixed number of
   808 binders, it can deal with arbitrary expressions standing for sets of
   809 atoms to be avoided.  The only inductive definition we have at the
   810 moment that needs this generalisation is the typing rule for Lets in
   811 the algorithm W:
   812 
   813  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
   814  -----------------------------------------------------------------
   815          Gamma |- Let x be t1 in t2 : T2
   816 
   817 In this rule one wants to avoid all the binders that are introduced by
   818 "close Gamma T1".  We are looking for other examples where this
   819 feature might be useful.  Please let us know.
   820 
   821 
   822 *** HOLCF ***
   823 
   824 * Reimplemented the simplification procedure for proving continuity
   825 subgoals.  The new simproc is extensible; users can declare additional
   826 continuity introduction rules with the attribute [cont2cont].
   827 
   828 * The continuity simproc now uses a different introduction rule for
   829 solving continuity subgoals on terms with lambda abstractions.  In
   830 some rare cases the new simproc may fail to solve subgoals that the
   831 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
   832 Potential INCOMPATIBILITY.
   833 
   834 * Command 'fixrec': specification syntax now conforms to the general
   835 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
   836 examples.  INCOMPATIBILITY.
   837 
   838 
   839 *** ZF ***
   840 
   841 * Proof of Zorn's Lemma for partial orders.
   842 
   843 
   844 *** ML ***
   845 
   846 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
   847 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
   848 depends on multithreading, so timouts will not work before Poly/ML
   849 5.2.1!
   850 
   851 * High-level support for concurrent ML programming, see
   852 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
   853 particularly convenient to organize independent functional
   854 computations.  The concept of "synchronized variables" provides a
   855 higher-order interface for components with shared state, avoiding the
   856 delicate details of mutexes and condition variables.  (Requires
   857 Poly/ML 5.2.1 or later.)
   858 
   859 * ML bindings produced via Isar commands are stored within the Isar
   860 context (theory or proof).  Consequently, commands like 'use' and 'ML'
   861 become thread-safe and work with undo as expected (concerning
   862 top-level bindings, not side-effects on global references).
   863 INCOMPATIBILITY, need to provide proper Isar context when invoking the
   864 compiler at runtime; really global bindings need to be given outside a
   865 theory.  (Requires Poly/ML 5.2 or later.)
   866 
   867 * Command 'ML_prf' is analogous to 'ML' but works within a proof
   868 context.  Top-level ML bindings are stored within the proof context in
   869 a purely sequential fashion, disregarding the nested proof structure.
   870 ML bindings introduced by 'ML_prf' are discarded at the end of the
   871 proof.  (Requires Poly/ML 5.2 or later.)
   872 
   873 * Simplified ML attribute and method setup, cf. functions Attrib.setup
   874 and Method.setup, as well as Isar commands 'attribute_setup' and
   875 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
   876 existing code accordingly, or use plain 'setup' together with old
   877 Method.add_method.
   878 
   879 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
   880 to 'a -> thm, while results are always tagged with an authentic oracle
   881 name.  The Isar command 'oracle' is now polymorphic, no argument type
   882 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
   883 accordingly.  Note that extra performance may be gained by producing
   884 the cterm carefully, avoiding slow Thm.cterm_of.
   885 
   886 * Simplified interface for defining document antiquotations via
   887 ThyOutput.antiquotation, ThyOutput.output, and optionally
   888 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
   889 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
   890 examples.
   891 
   892 * More systematic treatment of long names, abstract name bindings, and
   893 name space operations.  Basic operations on qualified names have been
   894 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
   895 Long_Name.append.  Old type bstring has been mostly replaced by
   896 abstract type binding (see structure Binding), which supports precise
   897 qualification by packages and local theory targets, as well as proper
   898 tracking of source positions.  INCOMPATIBILITY, need to wrap old
   899 bstring values into Binding.name, or better pass through abstract
   900 bindings everywhere.  See further src/Pure/General/long_name.ML,
   901 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
   902 
   903 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
   904 LocalTheory.note etc.) now refer to the *full* internal name, not the
   905 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
   906 
   907 * Disposed old type and term read functions (Sign.read_def_typ,
   908 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
   909 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
   910 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
   911 Syntax.read_term_global etc.; see also OldGoals.read_term as last
   912 resort for legacy applications.
   913 
   914 * Disposed old declarations, tactics, tactic combinators that refer to
   915 the simpset or claset of an implicit theory (such as Addsimps,
   916 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
   917 embedded ML text, or local_simpset_of with a proper context passed as
   918 explicit runtime argument.
   919 
   920 * Rules and tactics that read instantiations (read_instantiate,
   921 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
   922 context, which is required for parsing and type-checking.  Moreover,
   923 the variables are specified as plain indexnames, not string encodings
   924 thereof.  INCOMPATIBILITY.
   925 
   926 * Generic Toplevel.add_hook interface allows to analyze the result of
   927 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
   928 for theorem dependency output of transactions resulting in a new
   929 theory state.
   930 
   931 * ML antiquotations: block-structured compilation context indicated by
   932 \<lbrace> ... \<rbrace>; additional antiquotation forms:
   933 
   934   @{binding name}                         - basic name binding
   935   @{let ?pat = term}                      - term abbreviation (HO matching)
   936   @{note name = fact}                     - fact abbreviation
   937   @{thm fact}                             - singleton fact (with attributes)
   938   @{thms fact}                            - general fact (with attributes)
   939   @{lemma prop by method}                 - singleton goal
   940   @{lemma prop by meth1 meth2}            - singleton goal
   941   @{lemma prop1 ... propN by method}      - general goal
   942   @{lemma prop1 ... propN by meth1 meth2} - general goal
   943   @{lemma (open) ...}                     - open derivation
   944 
   945 
   946 *** System ***
   947 
   948 * The Isabelle "emacs" tool provides a specific interface to invoke
   949 Proof General / Emacs, with more explicit failure if that is not
   950 installed (the old isabelle-interface script silently falls back on
   951 isabelle-process).  The PROOFGENERAL_HOME setting determines the
   952 installation location of the Proof General distribution.
   953 
   954 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
   955 the Isabelle process into a JVM/Scala application.  See
   956 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
   957 process wrapper has been discontinued.)
   958 
   959 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
   960 
   961 * Various status messages (with exact source position information) are
   962 emitted, if proper markup print mode is enabled.  This allows
   963 user-interface components to provide detailed feedback on internal
   964 prover operations.
   965 
   966 
   967 
   968 New in Isabelle2008 (June 2008)
   969 -------------------------------
   970 
   971 *** General ***
   972 
   973 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
   974 and updated, with formally checked references as hyperlinks.
   975 
   976 * Theory loader: use_thy (and similar operations) no longer set the
   977 implicit ML context, which was occasionally hard to predict and in
   978 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
   979 provides a proper context already.
   980 
   981 * Theory loader: old-style ML proof scripts being *attached* to a thy
   982 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
   983 'use' within a theory file will do the job.
   984 
   985 * Name space merge now observes canonical order, i.e. the second space
   986 is inserted into the first one, while existing entries in the first
   987 space take precedence.  INCOMPATIBILITY in rare situations, may try to
   988 swap theory imports.
   989 
   990 * Syntax: symbol \<chi> is now considered a letter.  Potential
   991 INCOMPATIBILITY in identifier syntax etc.
   992 
   993 * Outer syntax: string tokens no longer admit escaped white space,
   994 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
   995 white space without escapes.
   996 
   997 * Outer syntax: string tokens may contain arbitrary character codes
   998 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
   999 "foo_bar".
  1000 
  1001 
  1002 *** Pure ***
  1003 
  1004 * Context-dependent token translations.  Default setup reverts locally
  1005 fixed variables, and adds hilite markup for undeclared frees.
  1006 
  1007 * Unused theorems can be found using the new command 'unused_thms'.
  1008 There are three ways of invoking it:
  1009 
  1010 (1) unused_thms
  1011      Only finds unused theorems in the current theory.
  1012 
  1013 (2) unused_thms thy_1 ... thy_n -
  1014      Finds unused theorems in the current theory and all of its ancestors,
  1015      excluding the theories thy_1 ... thy_n and all of their ancestors.
  1016 
  1017 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  1018      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  1019      their ancestors, excluding the theories thy_1 ... thy_n and all of
  1020      their ancestors.
  1021 
  1022 In order to increase the readability of the list produced by
  1023 unused_thms, theorems that have been created by a particular instance
  1024 of a theory command such as 'inductive' or 'function' are considered
  1025 to belong to the same "group", meaning that if at least one theorem in
  1026 this group is used, the other theorems in the same group are no longer
  1027 reported as unused.  Moreover, if all theorems in the group are
  1028 unused, only one theorem in the group is displayed.
  1029 
  1030 Note that proof objects have to be switched on in order for
  1031 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  1032 usually the case when using Proof General with the default settings).
  1033 
  1034 * Authentic naming of facts disallows ad-hoc overwriting of previous
  1035 theorems within the same name space.  INCOMPATIBILITY, need to remove
  1036 duplicate fact bindings, or even accidental fact duplications.  Note
  1037 that tools may maintain dynamically scoped facts systematically, using
  1038 PureThy.add_thms_dynamic.
  1039 
  1040 * Command 'hide' now allows to hide from "fact" name space as well.
  1041 
  1042 * Eliminated destructive theorem database, simpset, claset, and
  1043 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  1044 update of theories within ML code.
  1045 
  1046 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  1047 INCOMPATIBILITY, object-logics depending on former Pure require
  1048 additional setup PureThy.old_appl_syntax_setup; object-logics
  1049 depending on former CPure need to refer to Pure.
  1050 
  1051 * Commands 'use' and 'ML' are now purely functional, operating on
  1052 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  1053 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  1054 INCOMPATIBILITY.
  1055 
  1056 * Command 'setup': discontinued implicit version with ML reference.
  1057 
  1058 * Instantiation target allows for simultaneous specification of class
  1059 instance operations together with an instantiation proof.
  1060 Type-checking phase allows to refer to class operations uniformly.
  1061 See src/HOL/Complex/Complex.thy for an Isar example and
  1062 src/HOL/Library/Eval.thy for an ML example.
  1063 
  1064 * Indexing of literal facts: be more serious about including only
  1065 facts from the visible specification/proof context, but not the
  1066 background context (locale etc.).  Affects `prop` notation and method
  1067 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  1068 situations.
  1069 
  1070 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  1071 "(open)" option, which used to expose internal bound variables to the
  1072 proof text.
  1073 
  1074 * Isar statements: removed obsolete case "rule_context".
  1075 INCOMPATIBILITY, better use explicit fixes/assumes.
  1076 
  1077 * Locale proofs: default proof step now includes 'unfold_locales';
  1078 hence 'proof' without argument may be used to unfold locale
  1079 predicates.
  1080 
  1081 
  1082 *** Document preparation ***
  1083 
  1084 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  1085 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  1086 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  1087 spot); renamed link color from "darkblue" to "linkcolor" (default
  1088 value unchanged, can be redefined via \definecolor); no longer sets
  1089 "a4paper" option (unnecessary or even intrusive).
  1090 
  1091 * Antiquotation @{lemma A method} proves proposition A by the given
  1092 method (either a method name or a method name plus (optional) method
  1093 arguments in parentheses) and prints A just like @{prop A}.
  1094 
  1095 
  1096 *** HOL ***
  1097 
  1098 * New primrec package.  Specification syntax conforms in style to
  1099 definition/function/....  No separate induction rule is provided.  The
  1100 "primrec" command distinguishes old-style and new-style specifications
  1101 by syntax.  The former primrec package is now named OldPrimrecPackage.
  1102 When adjusting theories, beware: constants stemming from new-style
  1103 primrec specifications have authentic syntax.
  1104 
  1105 * Metis prover is now an order of magnitude faster, and also works
  1106 with multithreading.
  1107 
  1108 * Metis: the maximum number of clauses that can be produced from a
  1109 theorem is now given by the attribute max_clauses.  Theorems that
  1110 exceed this number are ignored, with a warning printed.
  1111 
  1112 * Sledgehammer no longer produces structured proofs by default. To
  1113 enable, declare [[sledgehammer_full = true]].  Attributes
  1114 reconstruction_modulus, reconstruction_sorts renamed
  1115 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  1116 
  1117 * Method "induct_scheme" derives user-specified induction rules
  1118 from well-founded induction and completeness of patterns. This factors
  1119 out some operations that are done internally by the function package
  1120 and makes them available separately.  See
  1121 src/HOL/ex/Induction_Scheme.thy for examples.
  1122 
  1123 * More flexible generation of measure functions for termination
  1124 proofs: Measure functions can be declared by proving a rule of the
  1125 form "is_measure f" and giving it the [measure_function] attribute.
  1126 The "is_measure" predicate is logically meaningless (always true), and
  1127 just guides the heuristic.  To find suitable measure functions, the
  1128 termination prover sets up the goal "is_measure ?f" of the appropriate
  1129 type and generates all solutions by prolog-style backwards proof using
  1130 the declared rules.
  1131 
  1132 This setup also deals with rules like 
  1133 
  1134   "is_measure f ==> is_measure (list_size f)"
  1135 
  1136 which accommodates nested datatypes that recurse through lists.
  1137 Similar rules are predeclared for products and option types.
  1138 
  1139 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  1140 
  1141   INCOMPATIBILITIES:
  1142 
  1143   - Definitions of overloaded constants on sets have to be replaced by
  1144     definitions on => and bool.
  1145 
  1146   - Some definitions of overloaded operators on sets can now be proved
  1147     using the definitions of the operators on => and bool.  Therefore,
  1148     the following theorems have been renamed:
  1149 
  1150       subset_def   -> subset_eq
  1151       psubset_def  -> psubset_eq
  1152       set_diff_def -> set_diff_eq
  1153       Compl_def    -> Compl_eq
  1154       Sup_set_def  -> Sup_set_eq
  1155       Inf_set_def  -> Inf_set_eq
  1156       sup_set_def  -> sup_set_eq
  1157       inf_set_def  -> inf_set_eq
  1158 
  1159   - Due to the incompleteness of the HO unification algorithm, some
  1160     rules such as subst may require manual instantiation, if some of
  1161     the unknowns in the rule is a set.
  1162 
  1163   - Higher order unification and forward proofs:
  1164     The proof pattern
  1165 
  1166       have "P (S::'a set)" <...>
  1167       then have "EX S. P S" ..
  1168 
  1169     no longer works (due to the incompleteness of the HO unification
  1170     algorithm) and must be replaced by the pattern
  1171 
  1172       have "EX S. P S"
  1173       proof
  1174         show "P S" <...>
  1175       qed
  1176 
  1177   - Calculational reasoning with subst (or similar rules):
  1178     The proof pattern
  1179 
  1180       have "P (S::'a set)" <...>
  1181       also have "S = T" <...>
  1182       finally have "P T" .
  1183 
  1184     no longer works (for similar reasons as the previous example) and
  1185     must be replaced by something like
  1186 
  1187       have "P (S::'a set)" <...>
  1188       moreover have "S = T" <...>
  1189       ultimately have "P T" by simp
  1190 
  1191   - Tactics or packages written in ML code:
  1192     Code performing pattern matching on types via
  1193 
  1194       Type ("set", [T]) => ...
  1195 
  1196     must be rewritten. Moreover, functions like strip_type or
  1197     binder_types no longer return the right value when applied to a
  1198     type of the form
  1199 
  1200       T1 => ... => Tn => U => bool
  1201 
  1202     rather than
  1203 
  1204       T1 => ... => Tn => U set
  1205 
  1206 * Merged theories Wellfounded_Recursion, Accessible_Part and
  1207 Wellfounded_Relations to theory Wellfounded.
  1208 
  1209 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  1210 
  1211 * Class finite no longer treats UNIV as class parameter.  Use class
  1212 enum from theory Library/Enum instead to achieve a similar effect.
  1213 INCOMPATIBILITY.
  1214 
  1215 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  1216 and "Cons".  INCOMPATIBILITY.
  1217 
  1218 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  1219 Potential INCOMPATIBILITY.
  1220 
  1221 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  1222 injective_fst_snd removed, use split_eta and prod_eqI instead.
  1223 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  1224 
  1225 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  1226 the same name in theory Orderings:
  1227 
  1228   less_trans
  1229   less_linear
  1230   le_imp_less_or_eq
  1231   le_less_trans
  1232   less_le_trans
  1233   less_not_sym
  1234   less_asym
  1235 
  1236 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  1237 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  1238 and different variable names.
  1239 
  1240 * Library/Option_ord.thy: Canonical order on option type.
  1241 
  1242 * Library/RBT.thy: Red-black trees, an efficient implementation of
  1243 finite maps.
  1244 
  1245 * Library/Countable.thy: Type class for countable types.
  1246 
  1247 * Theory Int: The representation of numerals has changed.  The infix
  1248 operator BIT and the bit datatype with constructors B0 and B1 have
  1249 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  1250 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  1251 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  1252 accordingly.
  1253 
  1254 * Theory Nat: definition of <= and < on natural numbers no longer
  1255 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  1256 le_def and less_def have disappeared.  Consider lemmas not_less
  1257 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  1258 
  1259 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  1260 (whose purpose mainly is for various fold_set functionals) have been
  1261 abandoned in favor of the existing algebraic classes
  1262 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  1263 lower_semilattice (resp. upper_semilattice) and linorder.
  1264 INCOMPATIBILITY.
  1265 
  1266 * Theory Transitive_Closure: induct and cases rules now declare proper
  1267 case_names ("base" and "step").  INCOMPATIBILITY.
  1268 
  1269 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  1270 lattices.  The form set-specific version is available as
  1271 Inductive.lfp_ordinal_induct_set.
  1272 
  1273 * Renamed theorems "power.simps" to "power_int.simps".
  1274 INCOMPATIBILITY.
  1275 
  1276 * Class semiring_div provides basic abstract properties of semirings
  1277 with division and modulo operations.  Subsumes former class dvd_mod.
  1278 
  1279 * Merged theories IntDef, Numeral and IntArith into unified theory
  1280 Int.  INCOMPATIBILITY.
  1281 
  1282 * Theory Library/Code_Index: type "index" now represents natural
  1283 numbers rather than integers.  INCOMPATIBILITY.
  1284 
  1285 * New class "uminus" with operation "uminus" (split of from class
  1286 "minus" which now only has operation "minus", binary).
  1287 INCOMPATIBILITY.
  1288 
  1289 * Constants "card", "internal_split", "option_map" now with authentic
  1290 syntax.  INCOMPATIBILITY.
  1291 
  1292 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  1293 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  1294 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  1295 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  1296 Sup_set_def, le_def, less_def, option_map_def now with object
  1297 equality.  INCOMPATIBILITY.
  1298 
  1299 * Records. Removed K_record, and replaced it by pure lambda term
  1300 %x. c. The simplifier setup is now more robust against eta expansion.
  1301 INCOMPATIBILITY: in cases explicitly referring to K_record.
  1302 
  1303 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  1304 
  1305 * Library/ListVector: new theory of arithmetic vector operations.
  1306 
  1307 * Library/Order_Relation: new theory of various orderings as sets of
  1308 pairs.  Defines preorders, partial orders, linear orders and
  1309 well-orders on sets and on types.
  1310 
  1311 
  1312 *** ZF ***
  1313 
  1314 * Renamed some theories to allow to loading both ZF and HOL in the
  1315 same session:
  1316 
  1317   Datatype  -> Datatype_ZF
  1318   Inductive -> Inductive_ZF
  1319   Int       -> Int_ZF
  1320   IntDiv    -> IntDiv_ZF
  1321   Nat       -> Nat_ZF
  1322   List      -> List_ZF
  1323   Main      -> Main_ZF
  1324 
  1325 INCOMPATIBILITY: ZF theories that import individual theories below
  1326 Main might need to be adapted.  Regular theory Main is still
  1327 available, as trivial extension of Main_ZF.
  1328 
  1329 
  1330 *** ML ***
  1331 
  1332 * ML within Isar: antiquotation @{const name} or @{const
  1333 name(typargs)} produces statically-checked Const term.
  1334 
  1335 * Functor NamedThmsFun: data is available to the user as dynamic fact
  1336 (of the same name).  Removed obsolete print command.
  1337 
  1338 * Removed obsolete "use_legacy_bindings" function.
  1339 
  1340 * The ``print mode'' is now a thread-local value derived from a global
  1341 template (the former print_mode reference), thus access becomes
  1342 non-critical.  The global print_mode reference is for session
  1343 management only; user-code should use print_mode_value,
  1344 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  1345 
  1346 * Functions system/system_out provide a robust way to invoke external
  1347 shell commands, with propagation of interrupts (requires Poly/ML
  1348 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  1349 
  1350 
  1351 *** System ***
  1352 
  1353 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  1354 in accordance with Proof General 3.7, which prefers GNU emacs.
  1355 
  1356 * isatool tty runs Isabelle process with plain tty interaction;
  1357 optional line editor may be specified via ISABELLE_LINE_EDITOR
  1358 setting, the default settings attempt to locate "ledit" and "rlwrap".
  1359 
  1360 * isatool browser now works with Cygwin as well, using general
  1361 "javapath" function defined in Isabelle process environment.
  1362 
  1363 * YXML notation provides a simple and efficient alternative to
  1364 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  1365 isatool yxml as described in the Isabelle system manual.
  1366 
  1367 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  1368 provides general wrapper for managing an Isabelle process in a robust
  1369 fashion, with ``cooked'' output from stdin/stderr.
  1370 
  1371 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  1372 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  1373 
  1374 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  1375 way of changing the user's settings is via
  1376 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  1377 script.
  1378 
  1379 * Multithreading.max_threads := 0 refers to the number of actual CPU
  1380 cores of the underlying machine, which is a good starting point for
  1381 optimal performance tuning.  The corresponding usedir option -M allows
  1382 "max" as an alias for "0".  WARNING: does not work on certain versions
  1383 of Mac OS (with Poly/ML 5.1).
  1384 
  1385 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  1386 adverse effect of Isabelle flooding interactive front-ends (notably
  1387 ProofGeneral / XEmacs).
  1388 
  1389 
  1390 
  1391 New in Isabelle2007 (November 2007)
  1392 -----------------------------------
  1393 
  1394 *** General ***
  1395 
  1396 * More uniform information about legacy features, notably a
  1397 warning/error of "Legacy feature: ...", depending on the state of the
  1398 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  1399 legacy features will disappear eventually.
  1400 
  1401 * Theory syntax: the header format ``theory A = B + C:'' has been
  1402 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  1403 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  1404 
  1405 * Theory syntax: the old non-Isar theory file format has been
  1406 discontinued altogether.  Note that ML proof scripts may still be used
  1407 with Isar theories; migration is usually quite simple with the ML
  1408 function use_legacy_bindings.  INCOMPATIBILITY.
  1409 
  1410 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  1411 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  1412 quotes.
  1413 
  1414 * Theory loader: be more serious about observing the static theory
  1415 header specifications (including optional directories), but not the
  1416 accidental file locations of previously successful loads.  The strict
  1417 update policy of former update_thy is now already performed by
  1418 use_thy, so the former has been removed; use_thys updates several
  1419 theories simultaneously, just as 'imports' within a theory header
  1420 specification, but without merging the results.  Potential
  1421 INCOMPATIBILITY: may need to refine theory headers and commands
  1422 ROOT.ML which depend on load order.
  1423 
  1424 * Theory loader: optional support for content-based file
  1425 identification, instead of the traditional scheme of full physical
  1426 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  1427 (cf. the system manual).  The new scheme allows to work with
  1428 non-finished theories in persistent session images, such that source
  1429 files may be moved later on without requiring reloads.
  1430 
  1431 * Theory loader: old-style ML proof scripts being *attached* to a thy
  1432 file (with the same base name as the theory) are considered a legacy
  1433 feature, which will disappear eventually. Even now, the theory loader
  1434 no longer maintains dependencies on such files.
  1435 
  1436 * Syntax: the scope for resolving ambiguities via type-inference is
  1437 now limited to individual terms, instead of whole simultaneous
  1438 specifications as before. This greatly reduces the complexity of the
  1439 syntax module and improves flexibility by separating parsing and
  1440 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  1441 'fixes' etc.) are required in rare situations.
  1442 
  1443 * Syntax: constants introduced by new-style packages ('definition',
  1444 'abbreviation' etc.) are passed through the syntax module in
  1445 ``authentic mode''. This means that associated mixfix annotations
  1446 really stick to such constants, independently of potential name space
  1447 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  1448 trees are represented slightly differently, may need to adapt syntax
  1449 translations accordingly. Use CONST marker in 'translations' and
  1450 @{const_syntax} antiquotation in 'parse_translation' etc.
  1451 
  1452 * Legacy goal package: reduced interface to the bare minimum required
  1453 to keep existing proof scripts running.  Most other user-level
  1454 functions are now part of the OldGoals structure, which is *not* open
  1455 by default (consider isatool expandshort before open OldGoals).
  1456 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  1457 these tend to cause confusion about the actual goal (!) context being
  1458 used here, which is not necessarily the same as the_context().
  1459 
  1460 * Command 'find_theorems': supports "*" wild-card in "name:"
  1461 criterion; "with_dups" option.  Certain ProofGeneral versions might
  1462 support a specific search form (see ProofGeneral/CHANGES).
  1463 
  1464 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  1465 by default, which means that "prems" (and also "fixed variables") are
  1466 suppressed from proof state output.  Note that the ProofGeneral
  1467 settings mechanism allows to change and save options persistently, but
  1468 older versions of Isabelle will fail to start up if a negative prems
  1469 limit is imposed.
  1470 
  1471 * Local theory targets may be specified by non-nested blocks of
  1472 ``context/locale/class ... begin'' followed by ``end''.  The body may
  1473 contain definitions, theorems etc., including any derived mechanism
  1474 that has been implemented on top of these primitives.  This concept
  1475 generalizes the existing ``theorem (in ...)'' towards more versatility
  1476 and scalability.
  1477 
  1478 * Proof General interface: proper undo of final 'end' command;
  1479 discontinued Isabelle/classic mode (ML proof scripts).
  1480 
  1481 
  1482 *** Document preparation ***
  1483 
  1484 * Added antiquotation @{theory name} which prints the given name,
  1485 after checking that it refers to a valid ancestor theory in the
  1486 current context.
  1487 
  1488 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  1489 check the given source text as ML type/structure, printing verbatim.
  1490 
  1491 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  1492 "c args == rhs" given in the current context.  (Any number of
  1493 arguments may be given on the LHS.)
  1494 
  1495 
  1496 *** Pure ***
  1497 
  1498 * The 'class' package offers a combination of axclass and locale to
  1499 achieve Haskell-like type classes in Isabelle.  Definitions and
  1500 theorems within a class context produce both relative results (with
  1501 implicit parameters according to the locale context), and polymorphic
  1502 constants with qualified polymorphism (according to the class
  1503 context).  Within the body context of a 'class' target, a separate
  1504 syntax layer ("user space type system") takes care of converting
  1505 between global polymorphic consts and internal locale representation.
  1506 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  1507 "isatool doc classes" provides a tutorial.
  1508 
  1509 * Generic code generator framework allows to generate executable
  1510 code for ML and Haskell (including Isabelle classes).  A short usage
  1511 sketch:
  1512 
  1513     internal compilation:
  1514         export_code <list of constants (term syntax)> in SML
  1515     writing SML code to a file:
  1516         export_code <list of constants (term syntax)> in SML <filename>
  1517     writing OCaml code to a file:
  1518         export_code <list of constants (term syntax)> in OCaml <filename>
  1519     writing Haskell code to a bunch of files:
  1520         export_code <list of constants (term syntax)> in Haskell <filename>
  1521 
  1522     evaluating closed propositions to True/False using code generation:
  1523         method ``eval''
  1524 
  1525 Reasonable default setup of framework in HOL.
  1526 
  1527 Theorem attributs for selecting and transforming function equations theorems:
  1528 
  1529     [code fun]:        select a theorem as function equation for a specific constant
  1530     [code fun del]:    deselect a theorem as function equation for a specific constant
  1531     [code inline]:     select an equation theorem for unfolding (inlining) in place
  1532     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  1533 
  1534 User-defined serializations (target in {SML, OCaml, Haskell}):
  1535 
  1536     code_const <and-list of constants (term syntax)>
  1537       {(target) <and-list of const target syntax>}+
  1538 
  1539     code_type <and-list of type constructors>
  1540       {(target) <and-list of type target syntax>}+
  1541 
  1542     code_instance <and-list of instances>
  1543       {(target)}+
  1544         where instance ::= <type constructor> :: <class>
  1545 
  1546     code_class <and_list of classes>
  1547       {(target) <and-list of class target syntax>}+
  1548         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  1549 
  1550 code_instance and code_class only are effective to target Haskell.
  1551 
  1552 For example usage see src/HOL/ex/Codegenerator.thy and
  1553 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  1554 generation from Isabelle/HOL theories is available via "isatool doc
  1555 codegen".
  1556 
  1557 * Code generator: consts in 'consts_code' Isar commands are now
  1558 referred to by usual term syntax (including optional type
  1559 annotations).
  1560 
  1561 * Command 'no_translations' removes translation rules from theory
  1562 syntax.
  1563 
  1564 * Overloaded definitions are now actually checked for acyclic
  1565 dependencies.  The overloading scheme is slightly more general than
  1566 that of Haskell98, although Isabelle does not demand an exact
  1567 correspondence to type class and instance declarations.
  1568 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  1569 exotic versions of overloading -- at the discretion of the user!
  1570 
  1571 Polymorphic constants are represented via type arguments, i.e. the
  1572 instantiation that matches an instance against the most general
  1573 declaration given in the signature.  For example, with the declaration
  1574 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  1575 as c(nat).  Overloading is essentially simultaneous structural
  1576 recursion over such type arguments.  Incomplete specification patterns
  1577 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  1578 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  1579 Command 'print_theory' outputs the normalized system of recursive
  1580 equations, see section "definitions".
  1581 
  1582 * Configuration options are maintained within the theory or proof
  1583 context (with name and type bool/int/string), providing a very simple
  1584 interface to a poor-man's version of general context data.  Tools may
  1585 declare options in ML (e.g. using Attrib.config_int) and then refer to
  1586 these values using Config.get etc.  Users may change options via an
  1587 associated attribute of the same name.  This form of context
  1588 declaration works particularly well with commands 'declare' or
  1589 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  1590 very easy to avoid global references, which would not observe Isar
  1591 toplevel undo/redo and fail to work with multithreading.
  1592 
  1593 Various global ML references of Pure and HOL have been turned into
  1594 configuration options:
  1595 
  1596   Unify.search_bound		unify_search_bound
  1597   Unify.trace_bound		unify_trace_bound
  1598   Unify.trace_simp		unify_trace_simp
  1599   Unify.trace_types		unify_trace_types
  1600   Simplifier.simp_depth_limit	simp_depth_limit
  1601   Blast.depth_limit		blast_depth_limit
  1602   DatatypeProp.dtK		datatype_distinctness_limit
  1603   fast_arith_neq_limit  	fast_arith_neq_limit
  1604   fast_arith_split_limit	fast_arith_split_limit
  1605 
  1606 * Named collections of theorems may be easily installed as context
  1607 data using the functor NamedThmsFun (see also
  1608 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  1609 attributes; there is also a toplevel print command.  This facility is
  1610 just a common case of general context data, which is the preferred way
  1611 for anything more complex than just a list of facts in canonical
  1612 order.
  1613 
  1614 * Isar: command 'declaration' augments a local theory by generic
  1615 declaration functions written in ML.  This enables arbitrary content
  1616 being added to the context, depending on a morphism that tells the
  1617 difference of the original declaration context wrt. the application
  1618 context encountered later on.
  1619 
  1620 * Isar: proper interfaces for simplification procedures.  Command
  1621 'simproc_setup' declares named simprocs (with match patterns, and body
  1622 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  1623 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  1624 
  1625 * Isar: an extra pair of brackets around attribute declarations
  1626 abbreviates a theorem reference involving an internal dummy fact,
  1627 which will be ignored later --- only the effect of the attribute on
  1628 the background context will persist.  This form of in-place
  1629 declarations is particularly useful with commands like 'declare' and
  1630 'using', for example ``have A using [[simproc a]] by simp''.
  1631 
  1632 * Isar: method "assumption" (and implicit closing of subproofs) now
  1633 takes simple non-atomic goal assumptions into account: after applying
  1634 an assumption as a rule the resulting subgoals are solved by atomic
  1635 assumption steps.  This is particularly useful to finish 'obtain'
  1636 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  1637 without referring to the original premise "!!x. P x ==> thesis" in the
  1638 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  1639 more permissive.
  1640 
  1641 * Isar: implicit use of prems from the Isar proof context is
  1642 considered a legacy feature.  Common applications like ``have A .''
  1643 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  1644 referencing facts explicitly here improves readability and
  1645 maintainability of proof texts.
  1646 
  1647 * Isar: improper proof element 'guess' is like 'obtain', but derives
  1648 the obtained context from the course of reasoning!  For example:
  1649 
  1650   assume "EX x y. A x & B y"   -- "any previous fact"
  1651   then guess x and y by clarify
  1652 
  1653 This technique is potentially adventurous, depending on the facts and
  1654 proof tools being involved here.
  1655 
  1656 * Isar: known facts from the proof context may be specified as literal
  1657 propositions, using ASCII back-quote syntax.  This works wherever
  1658 named facts used to be allowed so far, in proof commands, proof
  1659 methods, attributes etc.  Literal facts are retrieved from the context
  1660 according to unification of type and term parameters.  For example,
  1661 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  1662 theorems in the current context, then these are valid literal facts:
  1663 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  1664 
  1665 There is also a proof method "fact" which does the same composition
  1666 for explicit goal states, e.g. the following proof texts coincide with
  1667 certain special cases of literal facts:
  1668 
  1669   have "A" by fact                 ==  note `A`
  1670   have "A ==> B" by fact           ==  note `A ==> B`
  1671   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  1672   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  1673 
  1674 * Isar: ":" (colon) is no longer a symbolic identifier character in
  1675 outer syntax.  Thus symbolic identifiers may be used without
  1676 additional white space in declarations like this: ``assume *: A''.
  1677 
  1678 * Isar: 'print_facts' prints all local facts of the current context,
  1679 both named and unnamed ones.
  1680 
  1681 * Isar: 'def' now admits simultaneous definitions, e.g.:
  1682 
  1683   def x == "t" and y == "u"
  1684 
  1685 * Isar: added command 'unfolding', which is structurally similar to
  1686 'using', but affects both the goal state and facts by unfolding given
  1687 rewrite rules.  Thus many occurrences of the 'unfold' method or
  1688 'unfolded' attribute may be replaced by first-class proof text.
  1689 
  1690 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  1691 and command 'unfolding' now all support object-level equalities
  1692 (potentially conditional).  The underlying notion of rewrite rule is
  1693 analogous to the 'rule_format' attribute, but *not* that of the
  1694 Simplifier (which is usually more generous).
  1695 
  1696 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  1697 premises of a theorem by n. Useful in conjunction with drule.
  1698 
  1699 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  1700 method expression within a sandbox consisting of the first N
  1701 sub-goals, which need to exist.  For example, ``simp_all [3]''
  1702 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  1703 simplifies all new goals that emerge from applying rule foo to the
  1704 originally first one.
  1705 
  1706 * Isar: schematic goals are no longer restricted to higher-order
  1707 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  1708 expected.
  1709 
  1710 * Isar: the conclusion of a long theorem statement is now either
  1711 'shows' (a simultaneous conjunction, as before), or 'obtains'
  1712 (essentially a disjunction of cases with local parameters and
  1713 assumptions).  The latter allows to express general elimination rules
  1714 adequately; in this notation common elimination rules look like this:
  1715 
  1716   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  1717     assumes "EX x. P x"
  1718     obtains x where "P x"
  1719 
  1720   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  1721     assumes "A & B"
  1722     obtains A and B
  1723 
  1724   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  1725     assumes "A | B"
  1726     obtains
  1727       A
  1728     | B
  1729 
  1730 The subsequent classical rules even refer to the formal "thesis"
  1731 explicitly:
  1732 
  1733   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  1734     obtains "~ thesis"
  1735 
  1736   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  1737     obtains "thesis ==> something"
  1738 
  1739 The actual proof of an 'obtains' statement is analogous to that of the
  1740 Isar proof element 'obtain', only that there may be several cases.
  1741 Optional case names may be specified in parentheses; these will be
  1742 available both in the present proof and as annotations in the
  1743 resulting rule, for later use with the 'cases' method (cf. attribute
  1744 case_names).
  1745 
  1746 * Isar: the assumptions of a long theorem statement are available as
  1747 "assms" fact in the proof context.  This is more appropriate than the
  1748 (historical) "prems", which refers to all assumptions of the current
  1749 context, including those from the target locale, proof body etc.
  1750 
  1751 * Isar: 'print_statement' prints theorems from the current theory or
  1752 proof context in long statement form, according to the syntax of a
  1753 top-level lemma.
  1754 
  1755 * Isar: 'obtain' takes an optional case name for the local context
  1756 introduction rule (default "that").
  1757 
  1758 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  1759 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  1760 to occur.
  1761 
  1762 * Pure: syntax "CONST name" produces a fully internalized constant
  1763 according to the current context.  This is particularly useful for
  1764 syntax translations that should refer to internal constant
  1765 representations independently of name spaces.
  1766 
  1767 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  1768 instead of "FOO ". This allows multiple binder declarations to coexist
  1769 in the same context.  INCOMPATIBILITY.
  1770 
  1771 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  1772 primitive that also works in a locale context (both for constants and
  1773 fixed variables). Type declaration and internal syntactic representation
  1774 of given constants retrieved from the context. Likewise, the
  1775 'no_notation' command allows to remove given syntax annotations from the
  1776 current context.
  1777 
  1778 * Isar/locales: new derived specification elements 'axiomatization',
  1779 'definition', 'abbreviation', which support type-inference, admit
  1780 object-level specifications (equality, equivalence).  See also the
  1781 isar-ref manual.  Examples:
  1782 
  1783   axiomatization
  1784     eq  (infix "===" 50) where
  1785     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  1786 
  1787   definition "f x y = x + y + 1"
  1788   definition g where "g x = f x x"
  1789 
  1790   abbreviation
  1791     neq  (infix "=!=" 50) where
  1792     "x =!= y == ~ (x === y)"
  1793 
  1794 These specifications may be also used in a locale context.  Then the
  1795 constants being introduced depend on certain fixed parameters, and the
  1796 constant name is qualified by the locale base name.  An internal
  1797 abbreviation takes care for convenient input and output, making the
  1798 parameters implicit and using the original short name.  See also
  1799 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  1800 entities from a monomorphic theory.
  1801 
  1802 Presently, abbreviations are only available 'in' a target locale, but
  1803 not inherited by general import expressions.  Also note that
  1804 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  1805 'translations' in common applications.  The "no_abbrevs" print mode
  1806 prevents folding of abbreviations in term output.
  1807 
  1808 Concrete syntax is attached to specified constants in internal form,
  1809 independently of name spaces.  The parse tree representation is
  1810 slightly different -- use 'notation' instead of raw 'syntax', and
  1811 'translations' with explicit "CONST" markup to accommodate this.
  1812 
  1813 * Pure/Isar: unified syntax for new-style specification mechanisms
  1814 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  1815 full type inference and dummy patterns ("_").  For example:
  1816 
  1817   definition "K x _ = x"
  1818 
  1819   inductive conj for A B
  1820   where "A ==> B ==> conj A B"
  1821 
  1822 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  1823 the current context.  Print mode "no_abbrevs" prevents inversion of
  1824 abbreviations on output.
  1825 
  1826 * Isar/locales: improved parameter handling: use of locales "var" and
  1827 "struct" no longer necessary; - parameter renamings are no longer
  1828 required to be injective.  For example, this allows to define
  1829 endomorphisms as locale endom = homom mult mult h.
  1830 
  1831 * Isar/locales: changed the way locales with predicates are defined.
  1832 Instead of accumulating the specification, the imported expression is
  1833 now an interpretation.  INCOMPATIBILITY: different normal form of
  1834 locale expressions.  In particular, in interpretations of locales with
  1835 predicates, goals repesenting already interpreted fragments are not
  1836 removed automatically.  Use methods `intro_locales' and
  1837 `unfold_locales'; see below.
  1838 
  1839 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  1840 provide backward reasoning on locales predicates.  The methods are
  1841 aware of interpretations and discharge corresponding goals.
  1842 `intro_locales' is less aggressive then `unfold_locales' and does not
  1843 unfold predicates to assumptions.
  1844 
  1845 * Isar/locales: the order in which locale fragments are accumulated
  1846 has changed.  This enables to override declarations from fragments due
  1847 to interpretations -- for example, unwanted simp rules.
  1848 
  1849 * Isar/locales: interpretation in theories and proof contexts has been
  1850 extended.  One may now specify (and prove) equations, which are
  1851 unfolded in interpreted theorems.  This is useful for replacing
  1852 defined concepts (constants depending on locale parameters) by
  1853 concepts already existing in the target context.  Example:
  1854 
  1855   interpretation partial_order ["op <= :: [int, int] => bool"]
  1856     where "partial_order.less (op <=) (x::int) y = (x < y)"
  1857 
  1858 Typically, the constant `partial_order.less' is created by a
  1859 definition specification element in the context of locale
  1860 partial_order.
  1861 
  1862 * Method "induct": improved internal context management to support
  1863 local fixes and defines on-the-fly. Thus explicit meta-level
  1864 connectives !!  and ==> are rarely required anymore in inductive goals
  1865 (using object-logic connectives for this purpose has been long
  1866 obsolete anyway). Common proof patterns are explained in
  1867 src/HOL/Induct/Common_Patterns.thy, see also
  1868 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  1869 examples.
  1870 
  1871 * Method "induct": improved handling of simultaneous goals. Instead of
  1872 introducing object-level conjunction, the statement is now split into
  1873 several conclusions, while the corresponding symbolic cases are nested
  1874 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  1875 see src/HOL/Induct/Common_Patterns.thy, for example.
  1876 
  1877 * Method "induct": mutual induction rules are now specified as a list
  1878 of rule sharing the same induction cases. HOL packages usually provide
  1879 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  1880 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  1881 mutual induction rules differently, i.e. like this:
  1882 
  1883   (induct rule: foo_bar.inducts)
  1884   (induct set: foo bar)
  1885   (induct pred: foo bar)
  1886   (induct type: foo bar)
  1887 
  1888 The ML function ProjectRule.projections turns old-style rules into the
  1889 new format.
  1890 
  1891 * Method "coinduct": dual of induction, see
  1892 src/HOL/Library/Coinductive_List.thy for various examples.
  1893 
  1894 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  1895 considered a legacy feature.
  1896 
  1897 * Attribute "symmetric" produces result with standardized schematic
  1898 variables (index 0).  Potential INCOMPATIBILITY.
  1899 
  1900 * Simplifier: by default the simplifier trace only shows top level
  1901 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  1902 default. Thus there is less danger of being flooded by the trace. The
  1903 trace indicates where parts have been suppressed.
  1904   
  1905 * Provers/classical: removed obsolete classical version of elim_format
  1906 attribute; classical elim/dest rules are now treated uniformly when
  1907 manipulating the claset.
  1908 
  1909 * Provers/classical: stricter checks to ensure that supplied intro,
  1910 dest and elim rules are well-formed; dest and elim rules must have at
  1911 least one premise.
  1912 
  1913 * Provers/classical: attributes dest/elim/intro take an optional
  1914 weight argument for the rule (just as the Pure versions).  Weights are
  1915 ignored by automated tools, but determine the search order of single
  1916 rule steps.
  1917 
  1918 * Syntax: input syntax now supports dummy variable binding "%_. b",
  1919 where the body does not mention the bound variable.  Note that dummy
  1920 patterns implicitly depend on their context of bounds, which makes
  1921 "{_. _}" match any set comprehension as expected.  Potential
  1922 INCOMPATIBILITY -- parse translations need to cope with syntactic
  1923 constant "_idtdummy" in the binding position.
  1924 
  1925 * Syntax: removed obsolete syntactic constant "_K" and its associated
  1926 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  1927 for example "A -> B" => "Pi A (%_. B)".
  1928 
  1929 * Pure: 'class_deps' command visualizes the subclass relation, using
  1930 the graph browser tool.
  1931 
  1932 * Pure: 'print_theory' now suppresses certain internal declarations by
  1933 default; use '!' option for full details.
  1934 
  1935 
  1936 *** HOL ***
  1937 
  1938 * Method "metis" proves goals by applying the Metis general-purpose
  1939 resolution prover (see also http://gilith.com/software/metis/).
  1940 Examples are in the directory MetisExamples.  WARNING: the
  1941 Isabelle/HOL-Metis integration does not yet work properly with
  1942 multi-threading.
  1943   
  1944 * Command 'sledgehammer' invokes external automatic theorem provers as
  1945 background processes.  It generates calls to the "metis" method if
  1946 successful. These can be pasted into the proof.  Users do not have to
  1947 wait for the automatic provers to return.  WARNING: does not really
  1948 work with multi-threading.
  1949 
  1950 * New "auto_quickcheck" feature tests outermost goal statements for
  1951 potential counter-examples.  Controlled by ML references
  1952 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  1953 5000 milliseconds).  Fails silently if statements is outside of
  1954 executable fragment, or any other codgenerator problem occurs.
  1955 
  1956 * New constant "undefined" with axiom "undefined x = undefined".
  1957 
  1958 * Added class "HOL.eq", allowing for code generation with polymorphic
  1959 equality.
  1960 
  1961 * Some renaming of class constants due to canonical name prefixing in
  1962 the new 'class' package:
  1963 
  1964     HOL.abs ~> HOL.abs_class.abs
  1965     HOL.divide ~> HOL.divide_class.divide
  1966     0 ~> HOL.zero_class.zero
  1967     1 ~> HOL.one_class.one
  1968     op + ~> HOL.plus_class.plus
  1969     op - ~> HOL.minus_class.minus
  1970     uminus ~> HOL.minus_class.uminus
  1971     op * ~> HOL.times_class.times
  1972     op < ~> HOL.ord_class.less
  1973     op <= > HOL.ord_class.less_eq
  1974     Nat.power ~> Power.power_class.power
  1975     Nat.size ~> Nat.size_class.size
  1976     Numeral.number_of ~> Numeral.number_class.number_of
  1977     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  1978     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  1979     Orderings.min ~> Orderings.ord_class.min
  1980     Orderings.max ~> Orderings.ord_class.max
  1981     Divides.op div ~> Divides.div_class.div
  1982     Divides.op mod ~> Divides.div_class.mod
  1983     Divides.op dvd ~> Divides.div_class.dvd
  1984 
  1985 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  1986 
  1987 a) User-defined constants using any of the names "plus", "minus",
  1988 "times", "less" or "less_eq". The standard syntax translations for
  1989 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  1990 names.
  1991 
  1992 b) Variables named "plus", "minus", "times", "less", "less_eq"
  1993 INCOMPATIBILITY: use more specific names.
  1994 
  1995 c) Permutative equations (e.g. "a + b = b + a")
  1996 Since the change of names also changes the order of terms, permutative
  1997 rewrite rules may get applied in a different order. Experience shows
  1998 that this is rarely the case (only two adaptions in the whole Isabelle
  1999 distribution).  INCOMPATIBILITY: rewrite proofs
  2000 
  2001 d) ML code directly refering to constant names
  2002 This in general only affects hand-written proof tactics, simprocs and
  2003 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  2004 Consider using @{const_name} antiquotation.
  2005 
  2006 * New class "default" with associated constant "default".
  2007 
  2008 * Function "sgn" is now overloaded and available on int, real, complex
  2009 (and other numeric types), using class "sgn".  Two possible defs of
  2010 sgn are given as equational assumptions in the classes sgn_if and
  2011 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  2012 INCOMPATIBILITY.
  2013 
  2014 * Locale "partial_order" now unified with class "order" (cf. theory
  2015 Orderings), added parameter "less".  INCOMPATIBILITY.
  2016 
  2017 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  2018 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  2019 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  2020 
  2021 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  2022 changed order of proof goals in instance proofs.
  2023 
  2024 * The transitivity reasoner for partial and linear orders is set up
  2025 for classes "order" and "linorder".  Instances of the reasoner are available
  2026 in all contexts importing or interpreting the corresponding locales.
  2027 Method "order" invokes the reasoner separately; the reasoner
  2028 is also integrated with the Simplifier as a solver.  Diagnostic
  2029 command 'print_orders' shows the available instances of the reasoner
  2030 in the current context.
  2031 
  2032 * Localized monotonicity predicate in theory "Orderings"; integrated
  2033 lemmas max_of_mono and min_of_mono with this predicate.
  2034 INCOMPATIBILITY.
  2035 
  2036 * Formulation of theorem "dense" changed slightly due to integration
  2037 with new class dense_linear_order.
  2038 
  2039 * Uniform lattice theory development in HOL.
  2040 
  2041     constants "meet" and "join" now named "inf" and "sup"
  2042     constant "Meet" now named "Inf"
  2043 
  2044     classes "meet_semilorder" and "join_semilorder" now named
  2045       "lower_semilattice" and "upper_semilattice"
  2046     class "lorder" now named "lattice"
  2047     class "comp_lat" now named "complete_lattice"
  2048 
  2049     Instantiation of lattice classes allows explicit definitions
  2050     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  2051 
  2052   INCOMPATIBILITY.  Theorem renames:
  2053 
  2054     meet_left_le            ~> inf_le1
  2055     meet_right_le           ~> inf_le2
  2056     join_left_le            ~> sup_ge1
  2057     join_right_le           ~> sup_ge2
  2058     meet_join_le            ~> inf_sup_ord
  2059     le_meetI                ~> le_infI
  2060     join_leI                ~> le_supI
  2061     le_meet                 ~> le_inf_iff
  2062     le_join                 ~> ge_sup_conv
  2063     meet_idempotent         ~> inf_idem
  2064     join_idempotent         ~> sup_idem
  2065     meet_comm               ~> inf_commute
  2066     join_comm               ~> sup_commute
  2067     meet_leI1               ~> le_infI1
  2068     meet_leI2               ~> le_infI2
  2069     le_joinI1               ~> le_supI1
  2070     le_joinI2               ~> le_supI2
  2071     meet_assoc              ~> inf_assoc
  2072     join_assoc              ~> sup_assoc
  2073     meet_left_comm          ~> inf_left_commute
  2074     meet_left_idempotent    ~> inf_left_idem
  2075     join_left_comm          ~> sup_left_commute
  2076     join_left_idempotent    ~> sup_left_idem
  2077     meet_aci                ~> inf_aci
  2078     join_aci                ~> sup_aci
  2079     le_def_meet             ~> le_iff_inf
  2080     le_def_join             ~> le_iff_sup
  2081     join_absorp2            ~> sup_absorb2
  2082     join_absorp1            ~> sup_absorb1
  2083     meet_absorp1            ~> inf_absorb1
  2084     meet_absorp2            ~> inf_absorb2
  2085     meet_join_absorp        ~> inf_sup_absorb
  2086     join_meet_absorp        ~> sup_inf_absorb
  2087     distrib_join_le         ~> distrib_sup_le
  2088     distrib_meet_le         ~> distrib_inf_le
  2089 
  2090     add_meet_distrib_left   ~> add_inf_distrib_left
  2091     add_join_distrib_left   ~> add_sup_distrib_left
  2092     is_join_neg_meet        ~> is_join_neg_inf
  2093     is_meet_neg_join        ~> is_meet_neg_sup
  2094     add_meet_distrib_right  ~> add_inf_distrib_right
  2095     add_join_distrib_right  ~> add_sup_distrib_right
  2096     add_meet_join_distribs  ~> add_sup_inf_distribs
  2097     join_eq_neg_meet        ~> sup_eq_neg_inf
  2098     meet_eq_neg_join        ~> inf_eq_neg_sup
  2099     add_eq_meet_join        ~> add_eq_inf_sup
  2100     meet_0_imp_0            ~> inf_0_imp_0
  2101     join_0_imp_0            ~> sup_0_imp_0
  2102     meet_0_eq_0             ~> inf_0_eq_0
  2103     join_0_eq_0             ~> sup_0_eq_0
  2104     neg_meet_eq_join        ~> neg_inf_eq_sup
  2105     neg_join_eq_meet        ~> neg_sup_eq_inf
  2106     join_eq_if              ~> sup_eq_if
  2107 
  2108     mono_meet               ~> mono_inf
  2109     mono_join               ~> mono_sup
  2110     meet_bool_eq            ~> inf_bool_eq
  2111     join_bool_eq            ~> sup_bool_eq
  2112     meet_fun_eq             ~> inf_fun_eq
  2113     join_fun_eq             ~> sup_fun_eq
  2114     meet_set_eq             ~> inf_set_eq
  2115     join_set_eq             ~> sup_set_eq
  2116     meet1_iff               ~> inf1_iff
  2117     meet2_iff               ~> inf2_iff
  2118     meet1I                  ~> inf1I
  2119     meet2I                  ~> inf2I
  2120     meet1D1                 ~> inf1D1
  2121     meet2D1                 ~> inf2D1
  2122     meet1D2                 ~> inf1D2
  2123     meet2D2                 ~> inf2D2
  2124     meet1E                  ~> inf1E
  2125     meet2E                  ~> inf2E
  2126     join1_iff               ~> sup1_iff
  2127     join2_iff               ~> sup2_iff
  2128     join1I1                 ~> sup1I1
  2129     join2I1                 ~> sup2I1
  2130     join1I1                 ~> sup1I1
  2131     join2I2                 ~> sup1I2
  2132     join1CI                 ~> sup1CI
  2133     join2CI                 ~> sup2CI
  2134     join1E                  ~> sup1E
  2135     join2E                  ~> sup2E
  2136 
  2137     is_meet_Meet            ~> is_meet_Inf
  2138     Meet_bool_def           ~> Inf_bool_def
  2139     Meet_fun_def            ~> Inf_fun_def
  2140     Meet_greatest           ~> Inf_greatest
  2141     Meet_lower              ~> Inf_lower
  2142     Meet_set_def            ~> Inf_set_def
  2143 
  2144     Sup_def                 ~> Sup_Inf
  2145     Sup_bool_eq             ~> Sup_bool_def
  2146     Sup_fun_eq              ~> Sup_fun_def
  2147     Sup_set_eq              ~> Sup_set_def
  2148 
  2149     listsp_meetI            ~> listsp_infI
  2150     listsp_meet_eq          ~> listsp_inf_eq
  2151 
  2152     meet_min                ~> inf_min
  2153     join_max                ~> sup_max
  2154 
  2155 * Added syntactic class "size"; overloaded constant "size" now has
  2156 type "'a::size ==> bool"
  2157 
  2158 * Internal reorganisation of `size' of datatypes: size theorems
  2159 "foo.size" are no longer subsumed by "foo.simps" (but are still
  2160 simplification rules by default!); theorems "prod.size" now named
  2161 "*.size".
  2162 
  2163 * Class "div" now inherits from class "times" rather than "type".
  2164 INCOMPATIBILITY.
  2165 
  2166 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  2167 Linorder etc.  have disappeared; operations defined in terms of
  2168 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  2169 
  2170 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  2171 
  2172 * HOL-Word: New extensive library and type for generic, fixed size
  2173 machine words, with arithemtic, bit-wise, shifting and rotating
  2174 operations, reflection into int, nat, and bool lists, automation for
  2175 linear arithmetic (by automatic reflection into nat or int), including
  2176 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  2177 arithmetic type classes, supporting automatic simplification of
  2178 numerals on all operations.
  2179 
  2180 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  2181 
  2182 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  2183 
  2184 * Code generator library theories:
  2185   - Code_Integer represents HOL integers by big integer literals in target
  2186     languages.
  2187   - Code_Char represents HOL characters by character literals in target
  2188     languages.
  2189   - Code_Char_chr like Code_Char, but also offers treatment of character
  2190     codes; includes Code_Integer.
  2191   - Executable_Set allows to generate code for finite sets using lists.
  2192   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  2193     denominator).
  2194   - Executable_Real implements a subset of real numbers, namly those
  2195     representable by rational numbers.
  2196   - Efficient_Nat implements natural numbers by integers, which in general will
  2197     result in higher efficency; pattern matching with 0/Suc is eliminated;
  2198     includes Code_Integer.
  2199   - Code_Index provides an additional datatype index which is mapped to
  2200     target-language built-in integers.
  2201   - Code_Message provides an additional datatype message_string which is isomorphic to
  2202     strings; messages are mapped to target-language strings.
  2203 
  2204 * New package for inductive predicates
  2205 
  2206   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  2207 
  2208     inductive
  2209       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  2210       for z_1 :: U_1 and ... and z_n :: U_m
  2211     where
  2212       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  2213     | ...
  2214 
  2215   with full support for type-inference, rather than
  2216 
  2217     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  2218 
  2219     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  2220     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  2221 
  2222     inductive "s z_1 ... z_m"
  2223     intros
  2224       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  2225       ...
  2226 
  2227   For backward compatibility, there is a wrapper allowing inductive
  2228   sets to be defined with the new package via
  2229 
  2230     inductive_set
  2231       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  2232       for z_1 :: U_1 and ... and z_n :: U_m
  2233     where
  2234       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  2235     | ...
  2236 
  2237   or
  2238 
  2239     inductive_set
  2240       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  2241       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  2242       for z_1 :: U_1 and ... and z_n :: U_m
  2243     where
  2244       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  2245     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  2246     | ...
  2247 
  2248   if the additional syntax "p ..." is required.
  2249 
  2250   Numerous examples can be found in the subdirectories src/HOL/Auth,
  2251   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  2252 
  2253   INCOMPATIBILITIES:
  2254 
  2255   - Since declaration and definition of inductive sets or predicates
  2256     is no longer separated, abbreviations involving the newly
  2257     introduced sets or predicates must be specified together with the
  2258     introduction rules after the 'where' keyword (see above), rather
  2259     than before the actual inductive definition.
  2260 
  2261   - The variables in induction and elimination rules are now
  2262     quantified in the order of their occurrence in the introduction
  2263     rules, rather than in alphabetical order. Since this may break
  2264     some proofs, these proofs either have to be repaired, e.g. by
  2265     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  2266     statements of the form
  2267 
  2268       case (rule_i a_i_1 ... a_i_{k_i})
  2269 
  2270     or the old order of quantification has to be restored by explicitly adding
  2271     meta-level quantifiers in the introduction rules, i.e.
  2272 
  2273       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  2274 
  2275   - The format of the elimination rules is now
  2276 
  2277       p z_1 ... z_m x_1 ... x_n ==>
  2278         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  2279         ==> ... ==> P
  2280 
  2281     for predicates and
  2282 
  2283       (x_1, ..., x_n) : s z_1 ... z_m ==>
  2284         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  2285         ==> ... ==> P
  2286 
  2287     for sets rather than
  2288 
  2289       x : s z_1 ... z_m ==>
  2290         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  2291         ==> ... ==> P
  2292 
  2293     This may require terms in goals to be expanded to n-tuples
  2294     (e.g. using case_tac or simplification with the split_paired_all
  2295     rule) before the above elimination rule is applicable.
  2296 
  2297   - The elimination or case analysis rules for (mutually) inductive
  2298     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  2299     list of rules "p_1_..._p_k.elims" is no longer available.
  2300 
  2301 * New package "function"/"fun" for general recursive functions,
  2302 supporting mutual and nested recursion, definitions in local contexts,
  2303 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  2304 for small examples, and the separate tutorial on the function
  2305 package. The old recdef "package" is still available as before, but
  2306 users are encouraged to use the new package.
  2307 
  2308 * Method "lexicographic_order" automatically synthesizes termination
  2309 relations as lexicographic combinations of size measures. 
  2310 
  2311 * Case-expressions allow arbitrary constructor-patterns (including
  2312 "_") and take their order into account, like in functional
  2313 programming.  Internally, this is translated into nested
  2314 case-expressions; missing cases are added and mapped to the predefined
  2315 constant "undefined". In complicated cases printing may no longer show
  2316 the original input but the internal form. Lambda-abstractions allow
  2317 the same form of pattern matching: "% pat1 => e1 | ..." is an
  2318 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  2319 variable.
  2320 
  2321 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  2322 is an abbreviation for "of_nat :: nat => int". The simplification
  2323 rules for "of_nat" have been changed to work like "int" did
  2324 previously.  Potential INCOMPATIBILITY:
  2325   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  2326   - of_nat_diff and of_nat_mult are no longer default simp rules
  2327 
  2328 * Method "algebra" solves polynomial equations over (semi)rings using
  2329 Groebner bases. The (semi)ring structure is defined by locales and the
  2330 tool setup depends on that generic context. Installing the method for
  2331 a specific type involves instantiating the locale and possibly adding
  2332 declarations for computation on the coefficients.  The method is
  2333 already instantiated for natural numbers and for the axiomatic class
  2334 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  2335 CALCULEMUS 2007 for the general principles underlying this
  2336 architecture of context-aware proof-tools.
  2337 
  2338 * Method "ferrack" implements quantifier elimination over
  2339 special-purpose dense linear orders using locales (analogous to
  2340 "algebra"). The method is already installed for class
  2341 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  2342 rat, etc.
  2343 
  2344 * Former constant "List.op @" now named "List.append".  Use ML
  2345 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  2346 circumvent possible incompatibilities when working on ML level.
  2347 
  2348 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  2349 
  2350 * New function listsum :: 'a list => 'a for arbitrary monoids.
  2351 Special syntax: "SUM x <- xs. f x" (and latex variants)
  2352 
  2353 * New syntax for Haskell-like list comprehension (input only), eg.
  2354 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  2355 
  2356 * The special syntax for function "filter" has changed from [x :
  2357 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  2358 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  2359 
  2360 * [a..b] is now defined for arbitrary linear orders.  It used to be
  2361 defined on nat only, as an abbreviation for [a..<Suc b]
  2362 INCOMPATIBILITY.
  2363 
  2364 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  2365 
  2366 * New functions "sorted" and "sort" in src/HOL/List.thy.
  2367 
  2368 * New lemma collection field_simps (an extension of ring_simps) for
  2369 manipulating (in)equations involving division. Multiplies with all
  2370 denominators that can be proved to be non-zero (in equations) or
  2371 positive/negative (in inequations).
  2372 
  2373 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  2374 have been improved and renamed to ring_simps, group_simps and
  2375 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  2376 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  2377 
  2378 * Theory Library/Commutative_Ring: switched from recdef to function
  2379 package; constants add, mul, pow now curried.  Infix syntax for
  2380 algebraic operations.
  2381 
  2382 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  2383 INCOMPATIBILITY.
  2384 
  2385 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  2386 INCOMPATIBILITY.
  2387 
  2388 * HOL/records: generalised field-update to take a function on the
  2389 field rather than the new value: r(|A := x|) is translated to A_update
  2390 (K x) r The K-combinator that is internally used is called K_record.
  2391 INCOMPATIBILITY: Usage of the plain update functions has to be
  2392 adapted.
  2393  
  2394 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  2395 * x = 0, which are required for a semiring.  Richer structures do not
  2396 inherit from semiring_0 anymore, because this property is a theorem
  2397 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  2398 there is more to prove, but this is mostly trivial.
  2399 
  2400 * Class "recpower" is generalized to arbitrary monoids, not just
  2401 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  2402 commutativity or semiring properties additionally.
  2403 
  2404 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  2405 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  2406 better use 'abbreviation'.
  2407 
  2408 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  2409 
  2410 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  2411 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  2412 significant changes for setting up numeral syntax for types:
  2413   - New constants Numeral.pred and Numeral.succ instead
  2414       of former Numeral.bin_pred and Numeral.bin_succ.
  2415   - Use integer operations instead of bin_add, bin_mult and so on.
  2416   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  2417   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  2418 
  2419 See src/HOL/Integ/IntArith.thy for an example setup.
  2420 
  2421 * Command 'normal_form' computes the normal form of a term that may
  2422 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  2423 produces ``[b, c, a]'' (without proof).  This command is suitable for
  2424 heavy-duty computations because the functions are compiled to ML
  2425 first.  Correspondingly, a method "normalization" is provided.  See
  2426 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  2427 
  2428 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  2429 25 like -->); output depends on the "iff" print_mode, the default is
  2430 "A = B" (with priority 50).
  2431 
  2432 * Relations less (<) and less_eq (<=) are also available on type bool.
  2433 Modified syntax to disallow nesting without explicit parentheses,
  2434 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  2435 INCOMPATIBILITY.
  2436 
  2437 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  2438 
  2439 * Relation composition operator "op O" now has precedence 75 and binds
  2440 stronger than union and intersection. INCOMPATIBILITY.
  2441 
  2442 * The old set interval syntax "{m..n(}" (and relatives) has been
  2443 removed.  Use "{m..<n}" (and relatives) instead.
  2444 
  2445 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  2446 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  2447 ``declare [[simproc del: neq]]''.
  2448 
  2449 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  2450 True/False.
  2451 
  2452 * Theorem Cons_eq_map_conv no longer declared as "simp".
  2453 
  2454 * Theorem setsum_mult renamed to setsum_right_distrib.
  2455 
  2456 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  2457 ``rule'' method.
  2458 
  2459 * Reimplemented methods "sat" and "satx", with several improvements:
  2460 goals no longer need to be stated as "<prems> ==> False", equivalences
  2461 (i.e. "=" on type bool) are handled, variable names of the form
  2462 "lit_<n>" are no longer reserved, significant speedup.
  2463 
  2464 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  2465 zChaff is still supported as well.
  2466 
  2467 * 'inductive' and 'datatype': provide projections of mutual rules,
  2468 bundled as foo_bar.inducts;
  2469 
  2470 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  2471 Library.
  2472 
  2473 * Library: moved theory Accessible_Part to main HOL.
  2474 
  2475 * Library: added theory Coinductive_List of potentially infinite lists
  2476 as greatest fixed-point.
  2477 
  2478 * Library: added theory AssocList which implements (finite) maps as
  2479 association lists.
  2480 
  2481 * Method "evaluation" solves goals (i.e. a boolean expression)
  2482 efficiently by compiling it to ML.  The goal is "proved" (via an
  2483 oracle) if it evaluates to True.
  2484 
  2485 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  2486 also when invoked by the simplifier.  This results in the Simplifier
  2487 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  2488 Configuration option fast_arith_split_limit=0 recovers the old
  2489 behavior.
  2490 
  2491 * Support for hex (0x20) and binary (0b1001) numerals.
  2492 
  2493 * New method: reify eqs (t), where eqs are equations for an
  2494 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  2495 parameter, computes a term s::'b and a list xs::'a list and proves the
  2496 theorem I xs s = t. This is also known as reification or quoting. The
  2497 resulting theorem is applied to the subgoal to substitute t with I xs
  2498 s.  If t is omitted, the subgoal itself is reified.
  2499 
  2500 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  2501 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  2502 where f is supposed to be a computable function (in the sense of code
  2503 generattion). The method uses reify to compute s and xs as above then
  2504 applies corr_thm and uses normalization by evaluation to "prove" f s =
  2505 r and finally gets the theorem t = r, which is again applied to the
  2506 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  2507 
  2508 * Reflection: Automatic reification now handels binding, an example is
  2509 available in src/HOL/ex/ReflectionEx.thy
  2510 
  2511 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  2512 command 'statespace' that is similar to 'record', but introduces an
  2513 abstract specification based on the locale infrastructure instead of
  2514 HOL types.  This leads to extra flexibility in composing state spaces,
  2515 in particular multiple inheritance and renaming of components.
  2516 
  2517 
  2518 *** HOL-Complex ***
  2519 
  2520 * Hyperreal: Functions root and sqrt are now defined on negative real
  2521 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  2522 Nonnegativity side conditions have been removed from many lemmas, so
  2523 that more subgoals may now be solved by simplification; potential
  2524 INCOMPATIBILITY.
  2525 
  2526 * Real: new type classes formalize real normed vector spaces and
  2527 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  2528 and norm :: 'a => real.
  2529 
  2530 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  2531 reals into other types. The overloaded constant Reals :: 'a set is now
  2532 defined as range of_real; potential INCOMPATIBILITY.
  2533 
  2534 * Real: proper support for ML code generation, including 'quickcheck'.
  2535 Reals are implemented as arbitrary precision rationals.
  2536 
  2537 * Hyperreal: Several constants that previously worked only for the
  2538 reals have been generalized, so they now work over arbitrary vector
  2539 spaces. Type annotations may need to be added in some cases; potential
  2540 INCOMPATIBILITY.
  2541 
  2542   Infinitesimal  :: ('a::real_normed_vector) star set
  2543   HFinite        :: ('a::real_normed_vector) star set
  2544   HInfinite      :: ('a::real_normed_vector) star set
  2545   approx         :: ('a::real_normed_vector) star => 'a star => bool
  2546   monad          :: ('a::real_normed_vector) star => 'a star set
  2547   galaxy         :: ('a::real_normed_vector) star => 'a star set
  2548   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  2549   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  2550   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  2551   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  2552   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  2553   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  2554   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  2555   sgn            :: 'a::real_normed_vector => 'a
  2556   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  2557 
  2558 * Complex: Some complex-specific constants are now abbreviations for
  2559 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  2560 hnorm.  Other constants have been entirely removed in favor of the
  2561 polymorphic versions (INCOMPATIBILITY):
  2562 
  2563   approx        <-- capprox
  2564   HFinite       <-- CFinite
  2565   HInfinite     <-- CInfinite
  2566   Infinitesimal <-- CInfinitesimal
  2567   monad         <-- cmonad
  2568   galaxy        <-- cgalaxy
  2569   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  2570   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  2571   (ns)deriv     <-- (ns)cderiv
  2572 
  2573 
  2574 *** HOL-Algebra ***
  2575 
  2576 * Formalisation of ideals and the quotient construction over rings.
  2577 
  2578 * Order and lattice theory no longer based on records.
  2579 INCOMPATIBILITY.
  2580 
  2581 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  2582 greatest_closed.  INCOMPATIBILITY.
  2583 
  2584 * Method algebra is now set up via an attribute.  For examples see
  2585 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  2586 of algebraic structures.
  2587 
  2588 * Renamed theory CRing to Ring.
  2589 
  2590 
  2591 *** HOL-Nominal ***
  2592 
  2593 * Substantial, yet incomplete support for nominal datatypes (binding
  2594 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  2595 src/HOL/Nominal/Examples.  Prospective users should consult
  2596 http://isabelle.in.tum.de/nominal/
  2597 
  2598 
  2599 *** ML ***
  2600 
  2601 * ML basics: just one true type int, which coincides with IntInf.int
  2602 (even on SML/NJ).
  2603 
  2604 * ML within Isar: antiquotations allow to embed statically-checked
  2605 formal entities in the source, referring to the context available at
  2606 compile-time.  For example:
  2607 
  2608 ML {* @{sort "{zero,one}"} *}
  2609 ML {* @{typ "'a => 'b"} *}
  2610 ML {* @{term "%x. x"} *}
  2611 ML {* @{prop "x == y"} *}
  2612 ML {* @{ctyp "'a => 'b"} *}
  2613 ML {* @{cterm "%x. x"} *}
  2614 ML {* @{cprop "x == y"} *}
  2615 ML {* @{thm asm_rl} *}
  2616 ML {* @{thms asm_rl} *}
  2617 ML {* @{type_name c} *}
  2618 ML {* @{type_syntax c} *}
  2619 ML {* @{const_name c} *}
  2620 ML {* @{const_syntax c} *}
  2621 ML {* @{context} *}
  2622 ML {* @{theory} *}
  2623 ML {* @{theory Pure} *}
  2624 ML {* @{theory_ref} *}
  2625 ML {* @{theory_ref Pure} *}
  2626 ML {* @{simpset} *}
  2627 ML {* @{claset} *}
  2628 ML {* @{clasimpset} *}
  2629 
  2630 The same works for sources being ``used'' within an Isar context.
  2631 
  2632 * ML in Isar: improved error reporting; extra verbosity with
  2633 ML_Context.trace enabled.
  2634 
  2635 * Pure/General/table.ML: the join operations now works via exceptions
  2636 DUP/SAME instead of type option. This is simpler in simple cases, and
  2637 admits slightly more efficient complex applications.
  2638 
  2639 * Pure: 'advanced' translation functions (parse_translation etc.) now
  2640 use Context.generic instead of just theory.
  2641 
  2642 * Pure: datatype Context.generic joins theory/Proof.context and
  2643 provides some facilities for code that works in either kind of
  2644 context, notably GenericDataFun for uniform theory and proof data.
  2645 
  2646 * Pure: simplified internal attribute type, which is now always
  2647 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  2648 local (Proof.context) attributes have been discontinued, while
  2649 minimizing code duplication. Thm.rule_attribute and
  2650 Thm.declaration_attribute build canonical attributes; see also structure
  2651 Context for further operations on Context.generic, notably
  2652 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  2653 declarations and definitions.
  2654 
  2655 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  2656 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  2657 init only required for impure data. INCOMPATIBILITY: empty really need
  2658 to be empty (no dependencies on theory content!)
  2659 
  2660 * Pure/kernel: consts certification ignores sort constraints given in
  2661 signature declarations. (This information is not relevant to the
  2662 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  2663 potential INCOMPATIBILITY.
  2664 
  2665 * Pure: axiomatic type classes are now purely definitional, with
  2666 explicit proofs of class axioms and super class relations performed
  2667 internally. See Pure/axclass.ML for the main internal interfaces --
  2668 notably AxClass.define_class supercedes AxClass.add_axclass, and
  2669 AxClass.axiomatize_class/classrel/arity supersede
  2670 Sign.add_classes/classrel/arities.
  2671 
  2672 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  2673 global/local versions on theory vs. Proof.context have been
  2674 discontinued; Attrib.syntax and Method.syntax have been adapted
  2675 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  2676 attributes, methods, etc.
  2677 
  2678 * Pure: several functions of signature "... -> theory -> theory * ..."
  2679 have been reoriented to "... -> theory -> ... * theory" in order to
  2680 allow natural usage in combination with the ||>, ||>>, |-> and
  2681 fold_map combinators.
  2682 
  2683 * Pure: official theorem names (closed derivations) and additional
  2684 comments (tags) are now strictly separate.  Name hints -- which are
  2685 maintained as tags -- may be attached any time without affecting the
  2686 derivation.
  2687 
  2688 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  2689 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  2690 achieve the old behaviour.
  2691 
  2692 * Pure: the "Goal" constant is now called "prop", supporting a
  2693 slightly more general idea of ``protecting'' meta-level rule
  2694 statements.
  2695 
  2696 * Pure: Logic.(un)varify only works in a global context, which is now
  2697 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  2698 Logic.legacy_(un)varify as temporary workaround.
  2699 
  2700 * Pure: structure Name provides scalable operations for generating
  2701 internal variable names, notably Name.variants etc.  This replaces
  2702 some popular functions from term.ML:
  2703 
  2704   Term.variant		->  Name.variant
  2705   Term.variantlist	->  Name.variant_list
  2706   Term.invent_names	->  Name.invent_list
  2707 
  2708 Note that low-level renaming rarely occurs in new code -- operations
  2709 from structure Variable are used instead (see below).
  2710 
  2711 * Pure: structure Variable provides fundamental operations for proper
  2712 treatment of fixed/schematic variables in a context.  For example,
  2713 Variable.import introduces fixes for schematics of given facts and
  2714 Variable.export reverses the effect (up to renaming) -- this replaces
  2715 various freeze_thaw operations.
  2716 
  2717 * Pure: structure Goal provides simple interfaces for
  2718 init/conclude/finish and tactical prove operations (replacing former
  2719 Tactic.prove).  Goal.prove is the canonical way to prove results
  2720 within a given context; Goal.prove_global is a degraded version for
  2721 theory level goals, including a global Drule.standard.  Note that
  2722 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  2723 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  2724 in a locale context).
  2725 
  2726 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  2727 and type checking (Syntax.check_term etc.), with common combinations
  2728 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  2729 which are considered legacy and await removal.
  2730 
  2731 * Pure/Syntax: generic interfaces for type unchecking
  2732 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  2733 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  2734 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  2735 available for convenience, but refer to the very same operations using
  2736 a mere theory instead of a full context.
  2737 
  2738 * Isar: simplified treatment of user-level errors, using exception
  2739 ERROR of string uniformly.  Function error now merely raises ERROR,
  2740 without any side effect on output channels.  The Isar toplevel takes
  2741 care of proper display of ERROR exceptions.  ML code may use plain
  2742 handle/can/try; cat_error may be used to concatenate errors like this:
  2743 
  2744   ... handle ERROR msg => cat_error msg "..."
  2745 
  2746 Toplevel ML code (run directly or through the Isar toplevel) may be
  2747 embedded into the Isar toplevel with exception display/debug like
  2748 this:
  2749 
  2750   Isar.toplevel (fn () => ...)
  2751 
  2752 INCOMPATIBILITY, removed special transform_error facilities, removed
  2753 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  2754 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  2755 -- use plain ERROR instead.
  2756 
  2757 * Isar: theory setup now has type (theory -> theory), instead of a
  2758 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  2759 
  2760 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  2761 ProofContext.debug/verbose flags.
  2762 
  2763 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  2764 theory before entering a proof state.  Transactions now always see a
  2765 quasi-functional intermediate checkpoint, both in interactive and
  2766 batch mode.
  2767 
  2768 * Isar: simplified interfaces for outer syntax.  Renamed
  2769 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  2770 OuterSyntax.add_parsers -- this functionality is now included in
  2771 OuterSyntax.command etc.  INCOMPATIBILITY.
  2772 
  2773 * Simplifier: the simpset of a running simplification process now
  2774 contains a proof context (cf. Simplifier.the_context), which is the
  2775 very context that the initial simpset has been retrieved from (by
  2776 simpset_of/local_simpset_of).  Consequently, all plug-in components
  2777 (solver, looper etc.) may depend on arbitrary proof data.
  2778 
  2779 * Simplifier.inherit_context inherits the proof context (plus the
  2780 local bounds) of the current simplification process; any simproc
  2781 etc. that calls the Simplifier recursively should do this!  Removed
  2782 former Simplifier.inherit_bounds, which is already included here --
  2783 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  2784 specify an explicit context using Simplifier.context/theory_context.
  2785 
  2786 * Simplifier/Classical Reasoner: more abstract interfaces
  2787 change_simpset/claset for modifying the simpset/claset reference of a
  2788 theory; raw versions simpset/claset_ref etc. have been discontinued --
  2789 INCOMPATIBILITY.
  2790 
  2791 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  2792 "Trueprop" etc.
  2793 
  2794 
  2795 *** System ***
  2796 
  2797 * settings: the default heap location within ISABELLE_HOME_USER now
  2798 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  2799 Isabelle installations.
  2800 
  2801 * isabelle-process: option -S (secure mode) disables some critical
  2802 operations, notably runtime compilation and evaluation of ML source
  2803 code.
  2804 
  2805 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  2806 
  2807 * Support for parallel execution, using native multicore support of
  2808 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  2809 independent theories, according to the given theory header
  2810 specifications. The maximum number of worker threads is specified via
  2811 usedir option -M or the "max-threads" setting in Proof General. A
  2812 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  2813 to 6 on a 8-core machine.  User-code needs to observe certain
  2814 guidelines for thread-safe programming, see appendix A in the Isar
  2815 Implementation manual.
  2816 
  2817 
  2818 
  2819 New in Isabelle2005 (October 2005)
  2820 ----------------------------------
  2821 
  2822 *** General ***
  2823 
  2824 * Theory headers: the new header syntax for Isar theories is
  2825 
  2826   theory <name>
  2827   imports <theory1> ... <theoryN>
  2828   uses <file1> ... <fileM>
  2829   begin
  2830 
  2831 where the 'uses' part is optional.  The previous syntax
  2832 
  2833   theory <name> = <theory1> + ... + <theoryN>:
  2834 
  2835 will disappear in the next release.  Use isatool fixheaders to convert
  2836 existing theory files.  Note that there is no change in ancient
  2837 non-Isar theories now, but these will disappear soon.
  2838 
  2839 * Theory loader: parent theories can now also be referred to via
  2840 relative and absolute paths.
  2841 
  2842 * Command 'find_theorems' searches for a list of criteria instead of a
  2843 list of constants. Known criteria are: intro, elim, dest, name:string,
  2844 simp:term, and any term. Criteria can be preceded by '-' to select
  2845 theorems that do not match. Intro, elim, dest select theorems that
  2846 match the current goal, name:s selects theorems whose fully qualified
  2847 name contain s, and simp:term selects all simplification rules whose
  2848 lhs match term.  Any other term is interpreted as pattern and selects
  2849 all theorems matching the pattern. Available in ProofGeneral under
  2850 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  2851 
  2852   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  2853 
  2854 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  2855 matching the current goal as introduction rule and not having "HOL."
  2856 in their name (i.e. not being defined in theory HOL).
  2857 
  2858 * Command 'thms_containing' has been discontinued in favour of
  2859 'find_theorems'; INCOMPATIBILITY.
  2860 
  2861 * Communication with Proof General is now 8bit clean, which means that
  2862 Unicode text in UTF-8 encoding may be used within theory texts (both
  2863 formal and informal parts).  Cf. option -U of the Isabelle Proof
  2864 General interface.  Here are some simple examples (cf. src/HOL/ex):
  2865 
  2866   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  2867   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  2868 
  2869 * Improved efficiency of the Simplifier and, to a lesser degree, the
  2870 Classical Reasoner.  Typical big applications run around 2 times
  2871 faster.
  2872 
  2873 
  2874 *** Document preparation ***
  2875 
  2876 * Commands 'display_drafts' and 'print_drafts' perform simple output
  2877 of raw sources.  Only those symbols that do not require additional
  2878 LaTeX packages (depending on comments in isabellesym.sty) are
  2879 displayed properly, everything else is left verbatim.  isatool display
  2880 and isatool print are used as front ends (these are subject to the
  2881 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  2882 
  2883 * Command tags control specific markup of certain regions of text,
  2884 notably folding and hiding.  Predefined tags include "theory" (for
  2885 theory begin and end), "proof" for proof commands, and "ML" for
  2886 commands involving ML code; the additional tags "visible" and
  2887 "invisible" are unused by default.  Users may give explicit tag
  2888 specifications in the text, e.g. ''by %invisible (auto)''.  The
  2889 interpretation of tags is determined by the LaTeX job during document
  2890 preparation: see option -V of isatool usedir, or options -n and -t of
  2891 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  2892 \isadroptag.
  2893 
  2894 Several document versions may be produced at the same time via isatool
  2895 usedir (the generated index.html will link all of them).  Typical
  2896 specifications include ''-V document=theory,proof,ML'' to present
  2897 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  2898 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  2899 these parts without any formal replacement text.  The Isabelle site
  2900 default settings produce ''document'' and ''outline'' versions as
  2901 specified above.
  2902 
  2903 * Several new antiquotations:
  2904 
  2905   @{term_type term} prints a term with its type annotated;
  2906 
  2907   @{typeof term} prints the type of a term;
  2908 
  2909   @{const const} is the same as @{term const}, but checks that the
  2910   argument is a known logical constant;
  2911 
  2912   @{term_style style term} and @{thm_style style thm} print a term or
  2913   theorem applying a "style" to it
  2914 
  2915   @{ML text}
  2916 
  2917 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  2918 definitions, equations, inequations etc., 'concl' printing only the
  2919 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  2920 to print the specified premise.  TermStyle.add_style provides an ML
  2921 interface for introducing further styles.  See also the "LaTeX Sugar"
  2922 document practical applications.  The ML antiquotation prints
  2923 type-checked ML expressions verbatim.
  2924 
  2925 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  2926 and 'text' support optional locale specification '(in loc)', which
  2927 specifies the default context for interpreting antiquotations.  For
  2928 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  2929 
  2930 * Option 'locale=NAME' of antiquotations specifies an alternative
  2931 context interpreting the subsequent argument.  For example: @{thm
  2932 [locale=lattice] inf_assoc}.
  2933 
  2934 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  2935 a proof context.
  2936 
  2937 * Proper output of antiquotations for theory commands involving a
  2938 proof context (such as 'locale' or 'theorem (in loc) ...').
  2939 
  2940 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  2941 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  2942 
  2943 * isatool usedir: new option -C (default true) controls whether option
  2944 -D should include a copy of the original document directory; -C false
  2945 prevents unwanted effects such as copying of administrative CVS data.
  2946 
  2947 
  2948 *** Pure ***
  2949 
  2950 * Considerably improved version of 'constdefs' command.  Now performs
  2951 automatic type-inference of declared constants; additional support for
  2952 local structure declarations (cf. locales and HOL records), see also
  2953 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  2954 sequential dependencies of definitions within a single 'constdefs'
  2955 section; moreover, the declared name needs to be an identifier.  If
  2956 all fails, consider to fall back on 'consts' and 'defs' separately.
  2957 
  2958 * Improved indexed syntax and implicit structures.  First of all,
  2959 indexed syntax provides a notational device for subscripted
  2960 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  2961 expressions.  Secondly, in a local context with structure
  2962 declarations, number indexes \<^sub>n or the empty index (default
  2963 number 1) refer to a certain fixed variable implicitly; option
  2964 show_structs controls printing of implicit structures.  Typical
  2965 applications of these concepts involve record types and locales.
  2966 
  2967 * New command 'no_syntax' removes grammar declarations (and
  2968 translations) resulting from the given syntax specification, which is
  2969 interpreted in the same manner as for the 'syntax' command.
  2970 
  2971 * 'Advanced' translation functions (parse_translation etc.) may depend
  2972 on the signature of the theory context being presently used for
  2973 parsing/printing, see also isar-ref manual.
  2974 
  2975 * Improved 'oracle' command provides a type-safe interface to turn an
  2976 ML expression of type theory -> T -> term into a primitive rule of
  2977 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  2978 is already included here); see also FOL/ex/IffExample.thy;
  2979 INCOMPATIBILITY.
  2980 
  2981 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  2982 before); "cI" is no longer bound, use "c.intro" instead.
  2983 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  2984 axclasses vs. locales.
  2985 
  2986 * Improved internal renaming of symbolic identifiers -- attach primes
  2987 instead of base 26 numbers.
  2988 
  2989 * New flag show_question_marks controls printing of leading question
  2990 marks in schematic variable names.
  2991 
  2992 * In schematic variable names, *any* symbol following \<^isub> or
  2993 \<^isup> is now treated as part of the base name.  For example, the
  2994 following works without printing of awkward ".0" indexes:
  2995 
  2996   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  2997     by simp
  2998 
  2999 * Inner syntax includes (*(*nested*) comments*).
  3000 
  3001 * Pretty printer now supports unbreakable blocks, specified in mixfix
  3002 annotations as "(00...)".
  3003 
  3004 * Clear separation of logical types and nonterminals, where the latter
  3005 may only occur in 'syntax' specifications or type abbreviations.
  3006 Before that distinction was only partially implemented via type class
  3007 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  3008 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  3009 exotic syntax specifications may require further adaption
  3010 (e.g. Cube/Cube.thy).
  3011 
  3012 * Removed obsolete type class "logic", use the top sort {} instead.
  3013 Note that non-logical types should be declared as 'nonterminals'
  3014 rather than 'types'.  INCOMPATIBILITY for new object-logic
  3015 specifications.
  3016 
  3017 * Attributes 'induct' and 'cases': type or set names may now be
  3018 locally fixed variables as well.
  3019 
  3020 * Simplifier: can now control the depth to which conditional rewriting
  3021 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  3022 Limit.
  3023 
  3024 * Simplifier: simplification procedures may now take the current
  3025 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  3026 interface), which is very useful for calling the Simplifier
  3027 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  3028 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  3029 low-level mk_simproc no longer applies Logic.varify internally, to
  3030 allow for use in a context of fixed variables.
  3031 
  3032 * thin_tac now works even if the assumption being deleted contains !!
  3033 or ==>.  More generally, erule now works even if the major premise of
  3034 the elimination rule contains !! or ==>.
  3035 
  3036 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  3037 
  3038 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  3039 from Pure, which contains all common declarations already.  Both
  3040 theories are defined via plain Isabelle/Isar .thy files.
  3041 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  3042 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  3043 use isatool fixcpure to adapt your theory and ML sources.
  3044 
  3045 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  3046 selections of theorems in named facts via index ranges.
  3047 
  3048 * 'print_theorems': in theory mode, really print the difference
  3049 wrt. the last state (works for interactive theory development only),
  3050 in proof mode print all local facts (cf. 'print_facts');
  3051 
  3052 * 'hide': option '(open)' hides only base names.
  3053 
  3054 * More efficient treatment of intermediate checkpoints in interactive
  3055 theory development.
  3056 
  3057 * Code generator is now invoked via code_module (incremental code
  3058 generation) and code_library (modular code generation, ML structures
  3059 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  3060 must be quoted when used as identifiers.
  3061 
  3062 * New 'value' command for reading, evaluating and printing terms using
  3063 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  3064 quoted when used as identifier.
  3065 
  3066 
  3067 *** Locales ***
  3068 
  3069 * New commands for the interpretation of locale expressions in
  3070 theories (1), locales (2) and proof contexts (3).  These generate
  3071 proof obligations from the expression specification.  After the
  3072 obligations have been discharged, theorems of the expression are added
  3073 to the theory, target locale or proof context.  The synopsis of the
  3074 commands is a follows:
  3075 
  3076   (1) interpretation expr inst
  3077   (2) interpretation target < expr
  3078   (3) interpret expr inst
  3079 
  3080 Interpretation in theories and proof contexts require a parameter
  3081 instantiation of terms from the current context.  This is applied to
  3082 specifications and theorems of the interpreted expression.
  3083 Interpretation in locales only permits parameter renaming through the
  3084 locale expression.  Interpretation is smart in that interpretations
  3085 that are active already do not occur in proof obligations, neither are
  3086 instantiated theorems stored in duplicate.  Use 'print_interps' to
  3087 inspect active interpretations of a particular locale.  For details,
  3088 see the Isar Reference manual.  Examples can be found in
  3089 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  3090 
  3091 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  3092 'interpret' instead.
  3093 
  3094 * New context element 'constrains' for adding type constraints to
  3095 parameters.
  3096 
  3097 * Context expressions: renaming of parameters with syntax
  3098 redeclaration.
  3099 
  3100 * Locale declaration: 'includes' disallowed.
  3101 
  3102 * Proper static binding of attribute syntax -- i.e. types / terms /
  3103 facts mentioned as arguments are always those of the locale definition
  3104 context, independently of the context of later invocations.  Moreover,
  3105 locale operations (renaming and type / term instantiation) are applied
  3106 to attribute arguments as expected.
  3107 
  3108 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  3109 actual attributes; rare situations may require Attrib.attribute to
  3110 embed those attributes into Attrib.src that lack concrete syntax.
  3111 Attribute implementations need to cooperate properly with the static
  3112 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  3113 Attrib.XXX_thm etc. already do the right thing without further
  3114 intervention.  Only unusual applications -- such as "where" or "of"
  3115 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  3116 on the context and the facts involved -- may have to assign parsed
  3117 values to argument tokens explicitly.
  3118 
  3119 * Changed parameter management in theorem generation for long goal
  3120 statements with 'includes'.  INCOMPATIBILITY: produces a different
  3121 theorem statement in rare situations.
  3122 
  3123 * Locale inspection command 'print_locale' omits notes elements.  Use
  3124 'print_locale!' to have them included in the output.
  3125 
  3126 
  3127 *** Provers ***
  3128 
  3129 * Provers/hypsubst.ML: improved version of the subst method, for
  3130 single-step rewriting: it now works in bound variable contexts. New is
  3131 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  3132 rewrite a different subterm than the original subst method, which is
  3133 still available as 'simplesubst'.
  3134 
  3135 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  3136 and quasi orders.
  3137 
  3138 * Provers/trancl.ML: new transitivity reasoner for transitive and
  3139 reflexive-transitive closure of relations.
  3140 
  3141 * Provers/blast.ML: new reference depth_limit to make blast's depth
  3142 limit (previously hard-coded with a value of 20) user-definable.
  3143 
  3144 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  3145 is peformed already.  Object-logics merely need to finish their
  3146 initial simpset configuration as before.  INCOMPATIBILITY.
  3147 
  3148 
  3149 *** HOL ***
  3150 
  3151 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  3152 
  3153   syntax (epsilon)
  3154     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  3155 
  3156 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  3157 and x-symbol; use option '-m epsilon' to get it actually printed.
  3158 Moreover, the mathematically important symbolic identifier \<epsilon>
  3159 becomes available as variable, constant etc.  INCOMPATIBILITY,
  3160 
  3161 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  3162 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  3163 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  3164 support corresponding Isar calculations.
  3165 
  3166 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  3167 instead of ":".
  3168 
  3169 * theory SetInterval: changed the syntax for open intervals:
  3170 
  3171   Old       New
  3172   {..n(}    {..<n}
  3173   {)n..}    {n<..}
  3174   {m..n(}   {m..<n}
  3175   {)m..n}   {m<..n}
  3176   {)m..n(}  {m<..<n}
  3177 
  3178 The old syntax is still supported but will disappear in the next
  3179 release.  For conversion use the following Emacs search and replace
  3180 patterns (these are not perfect but work quite well):
  3181 
  3182   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  3183   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  3184 
  3185 * Theory Commutative_Ring (in Library): method comm_ring for proving
  3186 equalities in commutative rings; method 'algebra' provides a generic
  3187 interface.
  3188 
  3189 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  3190 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  3191 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  3192 be a tuple pattern.
  3193 
  3194 Some new syntax forms are available:
  3195 
  3196   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  3197   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  3198   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  3199   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  3200 
  3201 The latter form "\<Sum>x < k. e" used to be based on a separate
  3202 function "Summation", which has been discontinued.
  3203 
  3204 * theory Finite_Set: in structured induction proofs, the insert case
  3205 is now 'case (insert x F)' instead of the old counterintuitive 'case
  3206 (insert F x)'.
  3207 
  3208 * The 'refute' command has been extended to support a much larger
  3209 fragment of HOL, including axiomatic type classes, constdefs and
  3210 typedefs, inductive datatypes and recursion.
  3211 
  3212 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  3213 Requires zChaff with proof generation to be installed.  See
  3214 HOL/ex/SAT_Examples.thy for examples.
  3215 
  3216 * Datatype induction via method 'induct' now preserves the name of the
  3217 induction variable. For example, when proving P(xs::'a list) by
  3218 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  3219 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  3220 in unstructured proof scripts.
  3221 
  3222 * Reworked implementation of records.  Improved scalability for
  3223 records with many fields, avoiding performance problems for type
  3224 inference. Records are no longer composed of nested field types, but
  3225 of nested extension types. Therefore the record type only grows linear
  3226 in the number of extensions and not in the number of fields.  The
  3227 top-level (users) view on records is preserved.  Potential
  3228 INCOMPATIBILITY only in strange cases, where the theory depends on the
  3229 old record representation. The type generated for a record is called
  3230 <record_name>_ext_type.
  3231 
  3232 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  3233 proofs triggered by a record definition or a simproc (if
  3234 quick_and_dirty is enabled).  Definitions of large records can take
  3235 quite long.
  3236 
  3237 New simproc record_upd_simproc for simplification of multiple record
  3238 updates enabled by default.  Moreover, trivial updates are also
  3239 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  3240 occasionally, since simplification is more powerful by default.
  3241 
  3242 * typedef: proper support for polymorphic sets, which contain extra
  3243 type-variables in the term.
  3244 
  3245 * Simplifier: automatically reasons about transitivity chains
  3246 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  3247 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  3248 old proofs break occasionally as simplification may now solve more
  3249 goals than previously.
  3250 
  3251 * Simplifier: converts x <= y into x = y if assumption y <= x is
  3252 present.  Works for all partial orders (class "order"), in particular
  3253 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  3254 just like y <= x.
  3255 
  3256 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  3257 bound variable or a constant then the let is unfolded.  Otherwise
  3258 first a is simplified to b, and then f b is simplified to g. If
  3259 possible we abstract b from g arriving at "let x = b in h x",
  3260 otherwise we unfold the let and arrive at g.  The simproc can be
  3261 enabled/disabled by the reference use_let_simproc.  Potential
  3262 INCOMPATIBILITY since simplification is more powerful by default.
  3263 
  3264 * Classical reasoning: the meson method now accepts theorems as arguments.
  3265 
  3266 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  3267 jobs to provide advice on the provability of subgoals.
  3268 
  3269 * Theory OrderedGroup and Ring_and_Field: various additions and
  3270 improvements to faciliate calculations involving equalities and
  3271 inequalities.
  3272 
  3273 The following theorems have been eliminated or modified
  3274 (INCOMPATIBILITY):
  3275 
  3276   abs_eq             now named abs_of_nonneg
  3277   abs_of_ge_0        now named abs_of_nonneg
  3278   abs_minus_eq       now named abs_of_nonpos
  3279   imp_abs_id         now named abs_of_nonneg
  3280   imp_abs_neg_id     now named abs_of_nonpos
  3281   mult_pos           now named mult_pos_pos
  3282   mult_pos_le        now named mult_nonneg_nonneg
  3283   mult_pos_neg_le    now named mult_nonneg_nonpos
  3284   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  3285   mult_neg           now named mult_neg_neg
  3286   mult_neg_le        now named mult_nonpos_nonpos
  3287 
  3288 * The following lemmas in Ring_and_Field have been added to the simplifier:
  3289      
  3290      zero_le_square
  3291      not_square_less_zero 
  3292 
  3293   The following lemmas have been deleted from Real/RealPow:
  3294   
  3295      realpow_zero_zero
  3296      realpow_two
  3297      realpow_less
  3298      zero_le_power
  3299      realpow_two_le
  3300      abs_realpow_two
  3301      realpow_two_abs     
  3302 
  3303 * Theory Parity: added rules for simplifying exponents.
  3304 
  3305 * Theory List:
  3306 
  3307 The following theorems have been eliminated or modified
  3308 (INCOMPATIBILITY):
  3309 
  3310   list_all_Nil       now named list_all.simps(1)
  3311   list_all_Cons      now named list_all.simps(2)
  3312   list_all_conv      now named list_all_iff
  3313   set_mem_eq         now named mem_iff
  3314 
  3315 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  3316 asymptotic "big O" calculations.  See the notes in BigO.thy.
  3317 
  3318 
  3319 *** HOL-Complex ***
  3320 
  3321 * Theory RealDef: better support for embedding natural numbers and
  3322 integers in the reals.
  3323 
  3324 The following theorems have been eliminated or modified
  3325 (INCOMPATIBILITY):
  3326 
  3327   exp_ge_add_one_self  now requires no hypotheses
  3328   real_of_int_add      reversed direction of equality (use [symmetric])
  3329   real_of_int_minus    reversed direction of equality (use [symmetric])
  3330   real_of_int_diff     reversed direction of equality (use [symmetric])
  3331   real_of_int_mult     reversed direction of equality (use [symmetric])
  3332 
  3333 * Theory RComplete: expanded support for floor and ceiling functions.
  3334 
  3335 * Theory Ln is new, with properties of the natural logarithm
  3336 
  3337 * Hyperreal: There is a new type constructor "star" for making
  3338 nonstandard types.  The old type names are now type synonyms:
  3339 
  3340   hypreal = real star
  3341   hypnat = nat star
  3342   hcomplex = complex star
  3343 
  3344 * Hyperreal: Many groups of similarly-defined constants have been
  3345 replaced by polymorphic versions (INCOMPATIBILITY):
  3346 
  3347   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  3348 
  3349   starset      <-- starsetNat, starsetC
  3350   *s*          <-- *sNat*, *sc*
  3351   starset_n    <-- starsetNat_n, starsetC_n
  3352   *sn*         <-- *sNatn*, *scn*
  3353   InternalSets <-- InternalNatSets, InternalCSets
  3354 
  3355   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  3356   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  3357   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  3358   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  3359   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  3360 
  3361 * Hyperreal: Many type-specific theorems have been removed in favor of
  3362 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  3363 
  3364   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  3365   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  3366   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  3367   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  3368   right_minus <-- hypreal_add_minus
  3369   left_minus <-- {hypreal,hcomplex}_add_minus_left
  3370   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  3371   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  3372   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  3373   mult_1_right <-- hcomplex_mult_one_right
  3374   mult_zero_left <-- hcomplex_mult_zero_left
  3375   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  3376   right_distrib <-- hypnat_add_mult_distrib2
  3377   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  3378   right_inverse <-- hypreal_mult_inverse
  3379   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  3380   order_refl <-- {hypreal,hypnat}_le_refl
  3381   order_trans <-- {hypreal,hypnat}_le_trans
  3382   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  3383   order_less_le <-- {hypreal,hypnat}_less_le
  3384   linorder_linear <-- {hypreal,hypnat}_le_linear
  3385   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  3386   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  3387   add_nonneg_nonneg <-- hypreal_le_add_order
  3388 
  3389 * Hyperreal: Separate theorems having to do with type-specific
  3390 versions of constants have been merged into theorems that apply to the
  3391 new polymorphic constants (INCOMPATIBILITY):
  3392 
  3393   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  3394   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  3395   STAR_Un <-- {STAR,NatStar,STARC}_Un
  3396   STAR_Int <-- {STAR,NatStar,STARC}_Int
  3397   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  3398   STAR_subset <-- {STAR,NatStar,STARC}_subset
  3399   STAR_mem <-- {STAR,NatStar,STARC}_mem
  3400   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  3401   STAR_diff <-- {STAR,STARC}_diff
  3402   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  3403     STARC_hcomplex_of_complex}_image_subset
  3404   starset_n_Un <-- starset{Nat,C}_n_Un
  3405   starset_n_Int <-- starset{Nat,C}_n_Int
  3406   starset_n_Compl <-- starset{Nat,C}_n_Compl
  3407   starset_n_diff <-- starset{Nat,C}_n_diff
  3408   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  3409   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  3410   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  3411   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  3412   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  3413   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  3414   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  3415   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  3416   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  3417   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  3418   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  3419   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  3420   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  3421   starfun_diff <-- starfun{C,RC,CR}_diff
  3422   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  3423   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  3424   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  3425   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  3426   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  3427   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  3428   starfun_Id <-- starfunC_Id
  3429   starfun_approx <-- starfun{Nat,CR}_approx
  3430   starfun_capprox <-- starfun{C,RC}_capprox
  3431   starfun_abs <-- starfunNat_rabs
  3432   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  3433   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  3434   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  3435   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  3436   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  3437   starfun_add_approx <-- starfunCR_add_approx
  3438   starfun_inverse_inverse <-- starfunC_inverse_inverse
  3439   starfun_divide <-- starfun{C,CR,RC}_divide
  3440   starfun_n <-- starfun{Nat,C}_n
  3441   starfun_n_mult <-- starfun{Nat,C}_n_mult
  3442   starfun_n_add <-- starfun{Nat,C}_n_add
  3443   starfun_n_add_minus <-- starfunNat_n_add_minus
  3444   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  3445   starfun_n_minus <-- starfun{Nat,C}_n_minus
  3446   starfun_n_eq <-- starfun{Nat,C}_n_eq
  3447 
  3448   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  3449   star_n_minus <-- {hypreal,hcomplex}_minus
  3450   star_n_diff <-- {hypreal,hcomplex}_diff
  3451   star_n_mult <-- {hypreal,hcomplex}_mult
  3452   star_n_inverse <-- {hypreal,hcomplex}_inverse
  3453   star_n_le <-- {hypreal,hypnat}_le
  3454   star_n_less <-- {hypreal,hypnat}_less
  3455   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  3456   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  3457   star_n_abs <-- hypreal_hrabs
  3458   star_n_divide <-- hcomplex_divide
  3459 
  3460   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  3461   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  3462   star_of_diff <-- hypreal_of_real_diff
  3463   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  3464   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  3465   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  3466   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  3467   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  3468   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  3469   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  3470   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  3471   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  3472   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  3473   star_of_number_of <-- {hypreal,hcomplex}_number_of
  3474   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  3475   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  3476   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  3477   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  3478   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  3479   star_of_power <-- hypreal_of_real_power
  3480   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  3481 
  3482 * Hyperreal: new method "transfer" that implements the transfer
  3483 principle of nonstandard analysis. With a subgoal that mentions
  3484 nonstandard types like "'a star", the command "apply transfer"
  3485 replaces it with an equivalent one that mentions only standard types.
  3486 To be successful, all free variables must have standard types; non-
  3487 standard variables must have explicit universal quantifiers.
  3488 
  3489 * Hyperreal: A theory of Taylor series.
  3490 
  3491 
  3492 *** HOLCF ***
  3493 
  3494 * Discontinued special version of 'constdefs' (which used to support
  3495 continuous functions) in favor of the general Pure one with full
  3496 type-inference.
  3497 
  3498 * New simplification procedure for solving continuity conditions; it
  3499 is much faster on terms with many nested lambda abstractions (cubic
  3500 instead of exponential time).
  3501 
  3502 * New syntax for domain package: selector names are now optional.
  3503 Parentheses should be omitted unless argument is lazy, for example:
  3504 
  3505   domain 'a stream = cons "'a" (lazy "'a stream")
  3506 
  3507 * New command 'fixrec' for defining recursive functions with pattern
  3508 matching; defining multiple functions with mutual recursion is also
  3509 supported.  Patterns may include the constants cpair, spair, up, sinl,
  3510 sinr, or any data constructor defined by the domain package. The given
  3511 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  3512 syntax and examples.
  3513 
  3514 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  3515 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  3516 but the proof obligation additionally includes an admissibility
  3517 requirement. The packages generate instances of class cpo or pcpo,
  3518 with continuity and strictness theorems for Rep and Abs.
  3519 
  3520 * HOLCF: Many theorems have been renamed according to a more standard naming
  3521 scheme (INCOMPATIBILITY):
  3522 
  3523   foo_inject:  "foo$x = foo$y ==> x = y"
  3524   foo_eq:      "(foo$x = foo$y) = (x = y)"
  3525   foo_less:    "(foo$x << foo$y) = (x << y)"
  3526   foo_strict:  "foo$UU = UU"
  3527   foo_defined: "... ==> foo$x ~= UU"
  3528   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  3529 
  3530 
  3531 *** ZF ***
  3532 
  3533 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  3534 including the First Isomorphism Theorem (on quotienting by the kernel
  3535 of a homomorphism).
  3536 
  3537 * ZF/Simplifier: install second copy of type solver that actually
  3538 makes use of TC rules declared to Isar proof contexts (or locales);
  3539 the old version is still required for ML proof scripts.
  3540 
  3541 
  3542 *** Cube ***
  3543 
  3544 * Converted to Isar theory format; use locales instead of axiomatic
  3545 theories.
  3546 
  3547 
  3548 *** ML ***
  3549 
  3550 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  3551 for ||>, ||>>, |>>,
  3552 
  3553 * Pure/library.ML no longer defines its own option datatype, but uses
  3554 that of the SML basis, which has constructors NONE and SOME instead of
  3555 None and Some, as well as exception Option.Option instead of OPTION.
  3556 The functions the, if_none, is_some, is_none have been adapted
  3557 accordingly, while Option.map replaces apsome.
  3558 
  3559 * Pure/library.ML: the exception LIST has been given up in favour of
  3560 the standard exceptions Empty and Subscript, as well as
  3561 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  3562 superceded by the standard hd and tl functions etc.
  3563 
  3564 A number of basic list functions are no longer exported to the ML
  3565 toplevel, as they are variants of predefined functions.  The following
  3566 suggests how one can translate existing code:
  3567 
  3568     rev_append xs ys = List.revAppend (xs, ys)
  3569     nth_elem (i, xs) = List.nth (xs, i)
  3570     last_elem xs = List.last xs
  3571     flat xss = List.concat xss
  3572     seq fs = List.app fs
  3573     partition P xs = List.partition P xs
  3574     mapfilter f xs = List.mapPartial f xs
  3575 
  3576 * Pure/library.ML: several combinators for linear functional
  3577 transformations, notably reverse application and composition:
  3578 
  3579   x |> f                f #> g
  3580   (x, y) |-> f          f #-> g
  3581 
  3582 * Pure/library.ML: introduced/changed precedence of infix operators:
  3583 
  3584   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  3585   infix 2 ?;
  3586   infix 3 o oo ooo oooo;
  3587   infix 4 ~~ upto downto;
  3588 
  3589 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  3590 infix operators.
  3591 
  3592 * Pure/library.ML: natural list combinators fold, fold_rev, and
  3593 fold_map support linear functional transformations and nesting.  For
  3594 example:
  3595 
  3596   fold f [x1, ..., xN] y =
  3597     y |> f x1 |> ... |> f xN
  3598 
  3599   (fold o fold) f [xs1, ..., xsN] y =
  3600     y |> fold f xs1 |> ... |> fold f xsN
  3601 
  3602   fold f [x1, ..., xN] =
  3603     f x1 #> ... #> f xN
  3604 
  3605   (fold o fold) f [xs1, ..., xsN] =
  3606     fold f xs1 #> ... #> fold f xsN
  3607 
  3608 * Pure/library.ML: the following selectors on type 'a option are
  3609 available:
  3610 
  3611   the:               'a option -> 'a  (*partial*)
  3612   these:             'a option -> 'a  where 'a = 'b list
  3613   the_default: 'a -> 'a option -> 'a
  3614   the_list:          'a option -> 'a list
  3615 
  3616 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  3617 basic operations for association lists, following natural argument
  3618 order; moreover the explicit equality predicate passed here avoids
  3619 potentially expensive polymorphic runtime equality checks.
  3620 The old functions may be expressed as follows:
  3621 
  3622   assoc = uncurry (AList.lookup (op =))
  3623   assocs = these oo AList.lookup (op =)
  3624   overwrite = uncurry (AList.update (op =)) o swap
  3625 
  3626 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  3627 
  3628   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  3629   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  3630 
  3631 replacing make_keylist and keyfilter (occassionally used)
  3632 Naive rewrites:
  3633 
  3634   make_keylist = AList.make
  3635   keyfilter = AList.find (op =)
  3636 
  3637 * eq_fst and eq_snd now take explicit equality parameter, thus
  3638   avoiding eqtypes. Naive rewrites:
  3639 
  3640     eq_fst = eq_fst (op =)
  3641     eq_snd = eq_snd (op =)
  3642 
  3643 * Removed deprecated apl and apr (rarely used).
  3644   Naive rewrites:
  3645 
  3646     apl (n, op) =>>= curry op n
  3647     apr (op, m) =>>= fn n => op (n, m)
  3648 
  3649 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  3650 provides a reasonably efficient light-weight implementation of sets as
  3651 lists.
  3652 
  3653 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  3654 few new operations; existing lookup and update are now curried to
  3655 follow natural argument order (for use with fold etc.);
  3656 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  3657 
  3658 * Pure/General: output via the Isabelle channels of
  3659 writeln/warning/error etc. is now passed through Output.output, with a
  3660 hook for arbitrary transformations depending on the print_mode
  3661 (cf. Output.add_mode -- the first active mode that provides a output
  3662 function wins).  Already formatted output may be embedded into further
  3663 text via Output.raw; the result of Pretty.string_of/str_of and derived
  3664 functions (string_of_term/cterm/thm etc.) is already marked raw to
  3665 accommodate easy composition of diagnostic messages etc.  Programmers
  3666 rarely need to care about Output.output or Output.raw at all, with
  3667 some notable exceptions: Output.output is required when bypassing the
  3668 standard channels (writeln etc.), or in token translations to produce
  3669 properly formatted results; Output.raw is required when capturing
  3670 already output material that will eventually be presented to the user
  3671 a second time.  For the default print mode, both Output.output and
  3672 Output.raw have no effect.
  3673 
  3674 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  3675 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  3676 cumulative results are displayed at the end of a batch session.
  3677 
  3678 * Pure/General: File.sysify_path and File.quote_sysify path have been
  3679 replaced by File.platform_path and File.shell_path (with appropriate
  3680 hooks).  This provides a clean interface for unusual systems where the
  3681 internal and external process view of file names are different.
  3682 
  3683 * Pure: more efficient orders for basic syntactic entities: added
  3684 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  3685 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  3686 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  3687 orders now -- potential INCOMPATIBILITY for code that depends on a
  3688 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  3689 Library.sort_strings on result).
  3690 
  3691 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  3692 fold_types traverse types/terms from left to right, observing natural
  3693 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  3694 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  3695 
  3696 * Pure: name spaces have been refined, with significant changes of the
  3697 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  3698 to extern(_table).  The plain name entry path is superceded by a
  3699 general 'naming' context, which also includes the 'policy' to produce
  3700 a fully qualified name and external accesses of a fully qualified
  3701 name; NameSpace.extend is superceded by context dependent
  3702 Sign.declare_name.  Several theory and proof context operations modify
  3703 the naming context.  Especially note Theory.restore_naming and
  3704 ProofContext.restore_naming to get back to a sane state; note that
  3705 Theory.add_path is no longer sufficient to recover from
  3706 Theory.absolute_path in particular.
  3707 
  3708 * Pure: new flags short_names (default false) and unique_names
  3709 (default true) for controlling output of qualified names.  If
  3710 short_names is set, names are printed unqualified.  If unique_names is
  3711 reset, the name prefix is reduced to the minimum required to achieve
  3712 the original result when interning again, even if there is an overlap
  3713 with earlier declarations.
  3714 
  3715 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  3716 now 'extend', and 'merge' gets an additional Pretty.pp argument
  3717 (useful for printing error messages).  INCOMPATIBILITY.
  3718 
  3719 * Pure: major reorganization of the theory context.  Type Sign.sg and
  3720 Theory.theory are now identified, referring to the universal
  3721 Context.theory (see Pure/context.ML).  Actual signature and theory
  3722 content is managed as theory data.  The old code and interfaces were
  3723 spread over many files and structures; the new arrangement introduces
  3724 considerable INCOMPATIBILITY to gain more clarity:
  3725 
  3726   Context -- theory management operations (name, identity, inclusion,
  3727     parents, ancestors, merge, etc.), plus generic theory data;
  3728 
  3729   Sign -- logical signature and syntax operations (declaring consts,
  3730     types, etc.), plus certify/read for common entities;
  3731 
  3732   Theory -- logical theory operations (stating axioms, definitions,
  3733     oracles), plus a copy of logical signature operations (consts,
  3734     types, etc.); also a few basic management operations (Theory.copy,
  3735     Theory.merge, etc.)
  3736 
  3737 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  3738 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  3739 for convenience -- they merely return the theory.
  3740 
  3741 * Pure: type Type.tsig is superceded by theory in most interfaces.
  3742 
  3743 * Pure: the Isar proof context type is already defined early in Pure
  3744 as Context.proof (note that ProofContext.context and Proof.context are
  3745 aliases, where the latter is the preferred name).  This enables other
  3746 Isabelle components to refer to that type even before Isar is present.
  3747 
  3748 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  3749 typeK, constK, axiomK, oracleK), but provide explicit operations for
  3750 any of these kinds.  For example, Sign.intern typeK is now
  3751 Sign.intern_type, Theory.hide_space Sign.typeK is now
  3752 Theory.hide_types.  Also note that former
  3753 Theory.hide_classes/types/consts are now
  3754 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  3755 internalize their arguments!  INCOMPATIBILITY.
  3756 
  3757 * Pure: get_thm interface (of PureThy and ProofContext) expects
  3758 datatype thmref (with constructors Name and NameSelection) instead of
  3759 plain string -- INCOMPATIBILITY;
  3760 
  3761 * Pure: cases produced by proof methods specify options, where NONE
  3762 means to remove case bindings -- INCOMPATIBILITY in
  3763 (RAW_)METHOD_CASES.
  3764 
  3765 * Pure: the following operations retrieve axioms or theorems from a
  3766 theory node or theory hierarchy, respectively:
  3767 
  3768   Theory.axioms_of: theory -> (string * term) list
  3769   Theory.all_axioms_of: theory -> (string * term) list
  3770   PureThy.thms_of: theory -> (string * thm) list
  3771   PureThy.all_thms_of: theory -> (string * thm) list
  3772 
  3773 * Pure: print_tac now outputs the goal through the trace channel.
  3774 
  3775 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  3776 Reference Toplevel.debug (default false) controls detailed printing
  3777 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  3778 controls execution profiling -- set to 1 for time and 2 for space
  3779 (both increase the runtime).
  3780 
  3781 * Isar session: The initial use of ROOT.ML is now always timed,
  3782 i.e. the log will show the actual process times, in contrast to the
  3783 elapsed wall-clock time that the outer shell wrapper produces.
  3784 
  3785 * Simplifier: improved handling of bound variables (nameless
  3786 representation, avoid allocating new strings).  Simprocs that invoke
  3787 the Simplifier recursively should use Simplifier.inherit_bounds to
  3788 avoid local name clashes.  Failure to do so produces warnings
  3789 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  3790 for further details.
  3791 
  3792 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  3793 bindings for all theorems stored within a given theory; this may help
  3794 in porting non-Isar theories to Isar ones, while keeping ML proof
  3795 scripts for the time being.
  3796 
  3797 * ML operator HTML.with_charset specifies the charset begin used for
  3798 generated HTML files.  For example:
  3799 
  3800   HTML.with_charset "utf-8" use_thy "Hebrew";
  3801   HTML.with_charset "utf-8" use_thy "Chinese";
  3802 
  3803 
  3804 *** System ***
  3805 
  3806 * Allow symlinks to all proper Isabelle executables (Isabelle,
  3807 isabelle, isatool etc.).
  3808 
  3809 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  3810 isatool doc, isatool mkdir, display_drafts etc.).
  3811 
  3812 * isatool usedir: option -f allows specification of the ML file to be
  3813 used by Isabelle; default is ROOT.ML.
  3814 
  3815 * New isatool version outputs the version identifier of the Isabelle
  3816 distribution being used.
  3817 
  3818 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  3819 (containing Boolean satisfiability problems) into Isabelle/HOL
  3820 theories.
  3821 
  3822 
  3823 
  3824 New in Isabelle2004 (April 2004)
  3825 --------------------------------
  3826 
  3827 *** General ***
  3828 
  3829 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  3830   Replaces linorder.ML.
  3831 
  3832 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  3833   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  3834   (\<a>...\<z>), are now considered normal letters, and can therefore
  3835   be used anywhere where an ASCII letter (a...zA...Z) has until
  3836   now. COMPATIBILITY: This obviously changes the parsing of some
  3837   terms, especially where a symbol has been used as a binder, say
  3838   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  3839   as an identifier.  Fix it by inserting a space around former
  3840   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  3841   existing theory and ML files.
  3842 
  3843 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  3844 
  3845 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  3846   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  3847   a normal (but invisible) letter. For multiple letter subscripts repeat
  3848   \<^isub> like this: x\<^isub>1\<^isub>2.
  3849 
  3850 * Pure: There are now sub-/superscripts that can span more than one
  3851   character. Text between \<^bsub> and \<^esub> is set in subscript in
  3852   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  3853   superscript. The new control characters are not identifier parts.
  3854 
  3855 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  3856   content of "..." to the latex file instead of \isacntrl... . The "..."
  3857   may consist of any printable characters excluding the end bracket >.
  3858 
  3859 * Pure: Using new Isar command "finalconsts" (or the ML functions
  3860   Theory.add_finals or Theory.add_finals_i) it is now possible to
  3861   declare constants "final", which prevents their being given a definition
  3862   later.  It is useful for constants whose behaviour is fixed axiomatically
  3863   rather than definitionally, such as the meta-logic connectives.
  3864 
  3865 * Pure: 'instance' now handles general arities with general sorts
  3866   (i.e. intersections of classes),
  3867 
  3868 * Presentation: generated HTML now uses a CSS style sheet to make layout
  3869   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  3870   It can be changed to alter the colors/layout of generated pages.
  3871 
  3872 
  3873 *** Isar ***
  3874 
  3875 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  3876   cut_tac, subgoal_tac and thin_tac:
  3877   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  3878     locales are no longer forced to write Isar proof scripts.
  3879     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  3880     emulations.
  3881   - INCOMPATIBILITY: names of variables to be instantiated may no
  3882     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  3883     This is consistent with the instantiation attribute "where".
  3884 
  3885 * Attributes "where" and "of":
  3886   - Now take type variables of instantiated theorem into account when reading
  3887     the instantiation string.  This fixes a bug that caused instantiated
  3888     theorems to have too special types in some circumstances.
  3889   - "where" permits explicit instantiations of type variables.
  3890 
  3891 * Calculation commands "moreover" and "also" no longer interfere with
  3892   current facts ("this"), admitting arbitrary combinations with "then"
  3893   and derived forms.
  3894 
  3895 * Locales:
  3896   - Goal statements involving the context element "includes" no longer
  3897     generate theorems with internal delta predicates (those ending on
  3898     "_axioms") in the premise.
  3899     Resolve particular premise with <locale>.intro to obtain old form.
  3900   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  3901     specification and "includes" elements in goal statement.
  3902   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  3903     [intro?] and [elim?] (respectively) by default.
  3904   - Experimental command for instantiation of locales in proof contexts:
  3905         instantiate <label>[<attrs>]: <loc>
  3906     Instantiates locale <loc> and adds all its theorems to the current context
  3907     taking into account their attributes.  Label and attrs are optional
  3908     modifiers, like in theorem declarations.  If present, names of
  3909     instantiated theorems are qualified with <label>, and the attributes
  3910     <attrs> are applied after any attributes these theorems might have already.
  3911       If the locale has assumptions, a chained fact of the form
  3912     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  3913     are derived.  The command does not support old-style locales declared
  3914     with "locale (open)".
  3915       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  3916 
  3917 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  3918   (Isar) contexts.
  3919 
  3920 
  3921 *** HOL ***
  3922 
  3923 * Proof import: new image HOL4 contains the imported library from
  3924   the HOL4 system with about 2500 theorems. It is imported by
  3925   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  3926   can be used like any other Isabelle image.  See
  3927   HOL/Import/HOL/README for more information.
  3928 
  3929 * Simplifier:
  3930   - Much improved handling of linear and partial orders.
  3931     Reasoners for linear and partial orders are set up for type classes
  3932     "linorder" and "order" respectively, and are added to the default simpset
  3933     as solvers.  This means that the simplifier can build transitivity chains
  3934     to solve goals from the assumptions.
  3935   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  3936     of blast or auto after simplification become unnecessary because the goal
  3937     is solved by simplification already.
  3938 
  3939 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  3940     all proved in axiomatic type classes for semirings, rings and fields.
  3941 
  3942 * Numerics:
  3943   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  3944     now formalized using the Ring_and_Field theory mentioned above.
  3945   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  3946     than before, because now they are set up once in a generic manner.
  3947   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  3948     Look for the general versions in Ring_and_Field (and Power if they concern
  3949     exponentiation).
  3950 
  3951 * Type "rat" of the rational numbers is now available in HOL-Complex.
  3952 
  3953 * Records:
  3954   - Record types are now by default printed with their type abbreviation
  3955     instead of the list of all field types. This can be configured via
  3956     the reference "print_record_type_abbr".
  3957   - Simproc "record_upd_simproc" for simplification of multiple updates added
  3958     (not enabled by default).
  3959   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  3960     EX x. x = sel r to True (not enabled by default).
  3961   - Tactic "record_split_simp_tac" to split and simplify records added.
  3962 
  3963 * 'specification' command added, allowing for definition by
  3964   specification.  There is also an 'ax_specification' command that
  3965   introduces the new constants axiomatically.
  3966 
  3967 * arith(_tac) is now able to generate counterexamples for reals as well.
  3968 
  3969 * HOL-Algebra: new locale "ring" for non-commutative rings.
  3970 
  3971 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  3972   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  3973 
  3974 * HOL-Matrix: a first theory for matrices in HOL with an application of
  3975   matrix theory to linear programming.
  3976 
  3977 * Unions and Intersections:
  3978   The latex output syntax of UN and INT has been changed
  3979   from "\Union x \in A. B" to "\Union_{x \in A} B"
  3980   i.e. the index formulae has become a subscript.
  3981   Similarly for "\Union x. B", and for \Inter instead of \Union.
  3982 
  3983 * Unions and Intersections over Intervals:
  3984   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  3985   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  3986   like in normal math, and corresponding versions for < and for intersection.
  3987 
  3988 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  3989   lexicographic dictonary ordering has been added as "lexord".
  3990 
  3991 * ML: the legacy theory structures Int and List have been removed. They had
  3992   conflicted with ML Basis Library structures having the same names.
  3993 
  3994 * 'refute' command added to search for (finite) countermodels.  Only works
  3995   for a fragment of HOL.  The installation of an external SAT solver is
  3996   highly recommended.  See "HOL/Refute.thy" for details.
  3997 
  3998 * 'quickcheck' command: Allows to find counterexamples by evaluating
  3999   formulae under an assignment of free variables to random values.
  4000   In contrast to 'refute', it can deal with inductive datatypes,
  4001   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  4002   for examples.
  4003 
  4004 
  4005 *** HOLCF ***
  4006 
  4007 * Streams now come with concatenation and are part of the HOLCF image
  4008 
  4009 
  4010 
  4011 New in Isabelle2003 (May 2003)
  4012 ------------------------------
  4013 
  4014 *** General ***
  4015 
  4016 * Provers/simplifier:
  4017 
  4018   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  4019     Assumptions are now subject to complete mutual simplification,
  4020     not just from left to right. The simplifier now preserves
  4021     the order of assumptions.
  4022 
  4023     Potential INCOMPATIBILITY:
  4024 
  4025     -- simp sometimes diverges where the old version did
  4026        not, e.g. invoking simp on the goal
  4027 
  4028         [| P (f x); y = x; f x = f y |] ==> Q
  4029 
  4030        now gives rise to the infinite reduction sequence
  4031 
  4032         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  4033 
  4034        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  4035        kind of problem.
  4036 
  4037     -- Tactics combining classical reasoner and simplification (such as auto)
  4038        are also affected by this change, because many of them rely on
  4039        simp. They may sometimes diverge as well or yield a different numbers
  4040        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  4041        in case of problems. Sometimes subsequent calls to the classical
  4042        reasoner will fail because a preceeding call to the simplifier too
  4043        eagerly simplified the goal, e.g. deleted redundant premises.
  4044 
  4045   - The simplifier trace now shows the names of the applied rewrite rules
  4046 
  4047   - You can limit the number of recursive invocations of the simplifier
  4048     during conditional rewriting (where the simplifie tries to solve the
  4049     conditions before applying the rewrite rule):
  4050     ML "simp_depth_limit := n"
  4051     where n is an integer. Thus you can force termination where previously
  4052     the simplifier would diverge.
  4053 
  4054   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  4055 
  4056   - No longer aborts on failed congruence proof.  Instead, the
  4057     congruence is ignored.
  4058 
  4059 * Pure: New generic framework for extracting programs from constructive
  4060   proofs. See HOL/Extraction.thy for an example instantiation, as well
  4061   as HOL/Extraction for some case studies.
  4062 
  4063 * Pure: The main goal of the proof state is no longer shown by default, only
  4064 the subgoals. This behaviour is controlled by a new flag.
  4065    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  4066 (ML: Proof.show_main_goal).
  4067 
  4068 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  4069 rules whose conclusion matches subgoal 1:
  4070       PG menu: Isabelle/Isar -> Show me -> matching rules
  4071 The rules are ordered by how closely they match the subgoal.
  4072 In particular, rules that solve a subgoal outright are displayed first
  4073 (or rather last, the way they are printed).
  4074 (ML: ProofGeneral.print_intros())
  4075 
  4076 * Pure: New flag trace_unify_fail causes unification to print
  4077 diagnostic information (PG: in trace buffer) when it fails. This is
  4078 useful for figuring out why single step proofs like rule, erule or
  4079 assumption failed.
  4080 
  4081 * Pure: Locale specifications now produce predicate definitions
  4082 according to the body of text (covering assumptions modulo local
  4083 definitions); predicate "loc_axioms" covers newly introduced text,
  4084 while "loc" is cumulative wrt. all included locale expressions; the
  4085 latter view is presented only on export into the global theory
  4086 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  4087 on the old view without predicates;
  4088 
  4089 * Pure: predefined locales "var" and "struct" are useful for sharing
  4090 parameters (as in CASL, for example); just specify something like
  4091 ``var x + var y + struct M'' as import;
  4092 
  4093 * Pure: improved thms_containing: proper indexing of facts instead of
  4094 raw theorems; check validity of results wrt. current name space;
  4095 include local facts of proof configuration (also covers active
  4096 locales), cover fixed variables in index; may use "_" in term
  4097 specification; an optional limit for the number of printed facts may
  4098 be given (the default is 40);
  4099 
  4100 * Pure: disallow duplicate fact bindings within new-style theory files
  4101 (batch-mode only);
  4102 
  4103 * Provers: improved induct method: assumptions introduced by case
  4104 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  4105 the goal statement); "foo" still refers to all facts collectively;
  4106 
  4107 * Provers: the function blast.overloaded has been removed: all constants
  4108 are regarded as potentially overloaded, which improves robustness in exchange
  4109 for slight decrease in efficiency;
  4110 
  4111 * Provers/linorder: New generic prover for transitivity reasoning over
  4112 linear orders.  Note: this prover is not efficient!
  4113 
  4114 * Isar: preview of problems to finish 'show' now produce an error
  4115 rather than just a warning (in interactive mode);
  4116 
  4117 
  4118 *** HOL ***
  4119 
  4120 * arith(_tac)
  4121 
  4122  - Produces a counter example if it cannot prove a goal.
  4123    Note that the counter example may be spurious if the goal is not a formula
  4124    of quantifier-free linear arithmetic.
  4125    In ProofGeneral the counter example appears in the trace buffer.
  4126 
  4127  - Knows about div k and mod k where k is a numeral of type nat or int.
  4128 
  4129  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  4130    linear arithmetic fails. This takes account of quantifiers and divisibility.
  4131    Presburger arithmetic can also be called explicitly via presburger(_tac).
  4132 
  4133 * simp's arithmetic capabilities have been enhanced a bit: it now
  4134 takes ~= in premises into account (by performing a case split);
  4135 
  4136 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  4137 are distributed over a sum of terms;
  4138 
  4139 * New tactic "trans_tac" and method "trans" instantiate
  4140 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  4141 "<=", "<" and "=").
  4142 
  4143 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  4144 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  4145 
  4146 * 'typedef' command has new option "open" to suppress the set
  4147 definition;
  4148 
  4149 * functions Min and Max on finite sets have been introduced (theory
  4150 Finite_Set);
  4151 
  4152 * attribute [symmetric] now works for relations as well; it turns
  4153 (x,y) : R^-1 into (y,x) : R, and vice versa;
  4154 
  4155 * induct over a !!-quantified statement (say !!x1..xn):
  4156   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  4157 
  4158 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  4159 %x. None. Warning: empty_def now refers to the previously hidden definition
  4160 of the empty set.
  4161 
  4162 * Algebra: formalization of classical algebra.  Intended as base for
  4163 any algebraic development in Isabelle.  Currently covers group theory
  4164 (up to Sylow's theorem) and ring theory (Universal Property of
  4165 Univariate Polynomials).  Contributions welcome;
  4166 
  4167 * GroupTheory: deleted, since its material has been moved to Algebra;
  4168 
  4169 * Complex: new directory of the complex numbers with numeric constants,
  4170 nonstandard complex numbers, and some complex analysis, standard and
  4171 nonstandard (Jacques Fleuriot);
  4172 
  4173 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  4174 
  4175 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  4176 Fleuriot);
  4177 
  4178 * Real/HahnBanach: updated and adapted to locales;
  4179 
  4180 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  4181 Gray and Kramer);
  4182 
  4183 * UNITY: added the Meier-Sanders theory of progress sets;
  4184 
  4185 * MicroJava: bytecode verifier and lightweight bytecode verifier
  4186 as abstract algorithms, instantiated to the JVM;
  4187 
  4188 * Bali: Java source language formalization. Type system, operational
  4189 semantics, axiomatic semantics. Supported language features:
  4190 classes, interfaces, objects,virtual methods, static methods,
  4191 static/instance fields, arrays, access modifiers, definite
  4192 assignment, exceptions.
  4193 
  4194 
  4195 *** ZF ***
  4196 
  4197 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  4198 universe, etc.);
  4199 
  4200 * Main ZF: virtually all theories converted to new-style format;
  4201 
  4202 
  4203 *** ML ***
  4204 
  4205 * Pure: Tactic.prove provides sane interface for internal proofs;
  4206 omits the infamous "standard" operation, so this is more appropriate
  4207 than prove_goalw_cterm in many situations (e.g. in simprocs);
  4208 
  4209 * Pure: improved error reporting of simprocs;
  4210 
  4211 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  4212 up simprocs;
  4213 
  4214 
  4215 *** Document preparation ***
  4216 
  4217 * uses \par instead of \\ for line breaks in theory text. This may
  4218 shift some page breaks in large documents. To get the old behaviour
  4219 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  4220 
  4221 * minimized dependencies of isabelle.sty and isabellesym.sty on
  4222 other packages
  4223 
  4224 * \<euro> now needs package babel/greek instead of marvosym (which
  4225 broke \Rightarrow)
  4226 
  4227 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  4228 textcomp package)
  4229 
  4230 
  4231 
  4232 New in Isabelle2002 (March 2002)
  4233 --------------------------------
  4234 
  4235 *** Document preparation ***
  4236 
  4237 * greatly simplified document preparation setup, including more
  4238 graceful interpretation of isatool usedir -i/-d/-D options, and more
  4239 instructive isatool mkdir; users should basically be able to get
  4240 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  4241 users may run a separate document processing stage manually like this:
  4242 "isatool usedir -D output HOL Test && isatool document Test/output";
  4243 
  4244 * theory dependency graph may now be incorporated into documents;
  4245 isatool usedir -g true will produce session_graph.eps/.pdf for use
  4246 with \includegraphics of LaTeX;
  4247 
  4248 * proper spacing of consecutive markup elements, especially text
  4249 blocks after section headings;
  4250 
  4251 * support bold style (for single symbols only), input syntax is like
  4252 this: "\<^bold>\<alpha>" or "\<^bold>A";
  4253 
  4254 * \<bullet> is now output as bold \cdot by default, which looks much
  4255 better in printed text;
  4256 
  4257 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  4258 note that these symbols are currently unavailable in Proof General /
  4259 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  4260 
  4261 * isatool latex no longer depends on changed TEXINPUTS, instead
  4262 isatool document copies the Isabelle style files to the target
  4263 location;
  4264 
  4265 
  4266 *** Isar ***
  4267 
  4268 * Pure/Provers: improved proof by cases and induction;
  4269   - 'case' command admits impromptu naming of parameters (such as
  4270     "case (Suc n)");
  4271   - 'induct' method divinates rule instantiation from the inductive
  4272     claim; no longer requires excessive ?P bindings for proper
  4273     instantiation of cases;
  4274   - 'induct' method properly enumerates all possibilities of set/type
  4275     rules; as a consequence facts may be also passed through *type*
  4276     rules without further ado;
  4277   - 'induct' method now derives symbolic cases from the *rulified*
  4278     rule (before it used to rulify cases stemming from the internal
  4279     atomized version); this means that the context of a non-atomic
  4280     statement becomes is included in the hypothesis, avoiding the
  4281     slightly cumbersome show "PROP ?case" form;
  4282   - 'induct' may now use elim-style induction rules without chaining
  4283     facts, using ``missing'' premises from the goal state; this allows
  4284     rules stemming from inductive sets to be applied in unstructured
  4285     scripts, while still benefitting from proper handling of non-atomic
  4286     statements; NB: major inductive premises need to be put first, all
  4287     the rest of the goal is passed through the induction;
  4288   - 'induct' proper support for mutual induction involving non-atomic
  4289     rule statements (uses the new concept of simultaneous goals, see
  4290     below);
  4291   - append all possible rule selections, but only use the first
  4292     success (no backtracking);
  4293   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  4294   - undeclared rule case names default to numbers 1, 2, 3, ...;
  4295   - added 'print_induct_rules' (covered by help item in recent Proof
  4296     General versions);
  4297   - moved induct/cases attributes to Pure, methods to Provers;
  4298   - generic method setup instantiated for FOL and HOL;
  4299 
  4300 * Pure: support multiple simultaneous goal statements, for example
  4301 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  4302 meta-level mechanism, this acts as if several individual goals had
  4303 been stated separately; in particular common proof methods need to be
  4304 repeated in order to cover all claims; note that a single elimination
  4305 step is *not* sufficient to establish the two conjunctions, so this
  4306 fails:
  4307 
  4308   assume "A & B" then have A and B ..   (*".." fails*)
  4309 
  4310 better use "obtain" in situations as above; alternative refer to
  4311 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  4312 
  4313 * Pure: proper integration with ``locales''; unlike the original
  4314 version by Florian Kammller, Isar locales package high-level proof
  4315 contexts rather than raw logical ones (e.g. we admit to include
  4316 attributes everywhere); operations on locales include merge and
  4317 rename; support for implicit arguments (``structures''); simultaneous
  4318 type-inference over imports and text; see also HOL/ex/Locales.thy for
  4319 some examples;
  4320 
  4321 * Pure: the following commands have been ``localized'', supporting a
  4322 target locale specification "(in name)": 'lemma', 'theorem',
  4323 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  4324 stored both within the locale and at the theory level (exported and
  4325 qualified by the locale name);
  4326 
  4327 * Pure: theory goals may now be specified in ``long'' form, with
  4328 ad-hoc contexts consisting of arbitrary locale elements. for example
  4329 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  4330 definitions may be given, too); the result is a meta-level rule with
  4331 the context elements being discharged in the obvious way;
  4332 
  4333 * Pure: new proof command 'using' allows to augment currently used
  4334 facts after a goal statement ('using' is syntactically analogous to
  4335 'apply', but acts on the goal's facts only); this allows chained facts
  4336 to be separated into parts given before and after a claim, as in
  4337 ``from a and b have C using d and e <proof>'';
  4338 
  4339 * Pure: renamed "antecedent" case to "rule_context";
  4340 
  4341 * Pure: new 'judgment' command records explicit information about the
  4342 object-logic embedding (used by several tools internally); no longer
  4343 use hard-wired "Trueprop";
  4344 
  4345 * Pure: added 'corollary' command;
  4346 
  4347 * Pure: fixed 'token_translation' command;
  4348 
  4349 * Pure: removed obsolete 'exported' attribute;
  4350 
  4351 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  4352 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  4353 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  4354 
  4355 * Pure: method 'atomize' presents local goal premises as object-level
  4356 statements (atomic meta-level propositions); setup controlled via
  4357 rewrite rules declarations of 'atomize' attribute; example
  4358 application: 'induct' method with proper rule statements in improper
  4359 proof *scripts*;
  4360 
  4361 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  4362 now consider the syntactic context of assumptions, giving a better
  4363 chance to get type-inference of the arguments right (this is
  4364 especially important for locales);
  4365 
  4366 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  4367 mode;
  4368 
  4369 * Pure/obtain: the formal conclusion "thesis", being marked as
  4370 ``internal'', may no longer be reference directly in the text;
  4371 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  4372 situations;
  4373 
  4374 * Pure: generic 'sym' attribute which declares a rule both as pure
  4375 'elim?' and for the 'symmetric' operation;
  4376 
  4377 * Pure: marginal comments ``--'' may now occur just anywhere in the
  4378 text; the fixed correlation with particular command syntax has been
  4379 discontinued;
  4380 
  4381 * Pure: new method 'rules' is particularly well-suited for proof
  4382 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  4383 but often produces more compact proof terms with less detours;
  4384 
  4385 * Pure/Provers/classical: simplified integration with pure rule
  4386 attributes and methods; the classical "intro?/elim?/dest?"
  4387 declarations coincide with the pure ones; the "rule" method no longer
  4388 includes classically swapped intros; "intro" and "elim" methods no
  4389 longer pick rules from the context; also got rid of ML declarations
  4390 AddXIs/AddXEs/AddXDs; all of this has some potential for
  4391 INCOMPATIBILITY;
  4392 
  4393 * Provers/classical: attribute 'swapped' produces classical inversions
  4394 of introduction rules;
  4395 
  4396 * Provers/simplifier: 'simplified' attribute may refer to explicit
  4397 rules instead of full simplifier context; 'iff' attribute handles
  4398 conditional rules;
  4399 
  4400 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  4401 
  4402 * HOL: 'recdef' now fails on unfinished automated proofs, use
  4403 "(permissive)" option to recover old behavior;
  4404 
  4405 * HOL: 'inductive' no longer features separate (collective) attributes
  4406 for 'intros' (was found too confusing);
  4407 
  4408 * HOL: properly declared induction rules less_induct and
  4409 wf_induct_rule;
  4410 
  4411 
  4412 *** HOL ***
  4413 
  4414 * HOL: moved over to sane numeral syntax; the new policy is as
  4415 follows:
  4416 
  4417   - 0 and 1 are polymorphic constants, which are defined on any
  4418   numeric type (nat, int, real etc.);
  4419 
  4420   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  4421   binary representation internally;
  4422 
  4423   - type nat has special constructor Suc, and generally prefers Suc 0
  4424   over 1::nat and Suc (Suc 0) over 2::nat;
  4425 
  4426 This change may cause significant problems of INCOMPATIBILITY; here
  4427 are some hints on converting existing sources:
  4428 
  4429   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  4430   entities, so expressions involving "-" (unary or binary minus) need
  4431   to be spaced properly;
  4432 
  4433   - existing occurrences of "1" may need to be constraint "1::nat" or
  4434   even replaced by Suc 0; similar for old "2";
  4435 
  4436   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  4437 
  4438   - remove all special provisions on numerals in proofs;
  4439 
  4440 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  4441 representation (depends on bin_arith_simps in the default context);
  4442 
  4443 * HOL: symbolic syntax for x^2 (numeral 2);
  4444 
  4445 * HOL: the class of all HOL types is now called "type" rather than
  4446 "term"; INCOMPATIBILITY, need to adapt references to this type class
  4447 in axclass/classes, instance/arities, and (usually rare) occurrences
  4448 in typings (of consts etc.); internally the class is called
  4449 "HOL.type", ML programs should refer to HOLogic.typeS;
  4450 
  4451 * HOL/record package improvements:
  4452   - new derived operations "fields" to build a partial record section,
  4453     "extend" to promote a fixed record to a record scheme, and
  4454     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  4455     declared as simp by default;
  4456   - shared operations ("more", "fields", etc.) now need to be always
  4457     qualified) --- potential INCOMPATIBILITY;
  4458   - removed "make_scheme" operations (use "make" with "extend") --
  4459     INCOMPATIBILITY;
  4460   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  4461   - provides cases/induct rules for use with corresponding Isar
  4462     methods (for concrete records, record schemes, concrete more
  4463     parts, and schematic more parts -- in that order);
  4464   - internal definitions directly based on a light-weight abstract
  4465     theory of product types over typedef rather than datatype;
  4466 
  4467 * HOL: generic code generator for generating executable ML code from
  4468 specifications; specific support for HOL constructs such as inductive
  4469 datatypes and sets, as well as recursive functions; can be invoked
  4470 via 'generate_code' theory section;
  4471 
  4472 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  4473 
  4474 * HOL: consolidated and renamed several theories.  In particular:
  4475         Ord.thy has been absorbed into HOL.thy
  4476         String.thy has been absorbed into List.thy
  4477 
  4478 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  4479 (beware of argument permutation!);
  4480 
  4481 * HOL: linorder_less_split superseded by linorder_cases;
  4482 
  4483 * HOL/List: "nodups" renamed to "distinct";
  4484 
  4485 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  4486 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  4487   - Ex_def has changed, now need to use some_eq_ex
  4488 
  4489 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  4490 in this (rare) case use:
  4491 
  4492   delSWrapper "split_all_tac"
  4493   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  4494 
  4495 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  4496 MAY FAIL;
  4497 
  4498 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  4499 Isabelle's type classes, ^ on functions and relations has too general
  4500 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  4501 necessary to attach explicit type constraints;
  4502 
  4503 * HOL/Relation: the prefix name of the infix "O" has been changed from
  4504 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  4505 renamed accordingly (eg "compI" -> "rel_compI").
  4506 
  4507 * HOL: syntax translations now work properly with numerals and records
  4508 expressions;
  4509 
  4510 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  4511 of "lam" -- INCOMPATIBILITY;
  4512 
  4513 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  4514 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  4515 renamed "Product_Type.unit";
  4516 
  4517 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  4518 
  4519 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  4520 the "cases" method);
  4521 
  4522 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  4523 Florian Kammller);
  4524 
  4525 * HOL/IMP: updated and converted to new-style theory format; several
  4526 parts turned into readable document, with proper Isar proof texts and
  4527 some explanations (by Gerwin Klein);
  4528 
  4529 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  4530 
  4531 * HOL-Hyperreal is now a logic image;
  4532 
  4533 
  4534 *** HOLCF ***
  4535 
  4536 * Isar: consts/constdefs supports mixfix syntax for continuous
  4537 operations;
  4538 
  4539 * Isar: domain package adapted to new-style theory format, e.g. see
  4540 HOLCF/ex/Dnat.thy;
  4541 
  4542 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  4543 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  4544 lift.induct_tac, always use UU instead of Undef;
  4545 
  4546 * HOLCF/IMP: updated and converted to new-style theory;
  4547 
  4548 
  4549 *** ZF ***
  4550 
  4551 * Isar: proper integration of logic-specific tools and packages,
  4552 including theory commands '(co)inductive', '(co)datatype',
  4553 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  4554 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  4555 
  4556 * theory Main no longer includes AC; for the Axiom of Choice, base
  4557 your theory on Main_ZFC;
  4558 
  4559 * the integer library now covers quotients and remainders, with many
  4560 laws relating division to addition, multiplication, etc.;
  4561 
  4562 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  4563 typeless version of the formalism;
  4564 
  4565 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  4566 format;
  4567 
  4568 * ZF/Induct: new directory for examples of inductive definitions,
  4569 including theory Multiset for multiset orderings; converted to
  4570 new-style theory format;
  4571 
  4572 * ZF: many new theorems about lists, ordinals, etc.;
  4573 
  4574 
  4575 *** General ***
  4576 
  4577 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  4578 variable proof controls level of detail: 0 = no proofs (only oracle
  4579 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  4580 also ref manual for further ML interfaces;
  4581 
  4582 * Pure/axclass: removed obsolete ML interface
  4583 goal_subclass/goal_arity;
  4584 
  4585 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  4586 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  4587 separate tokens, so expressions involving minus need to be spaced
  4588 properly;
  4589 
  4590 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  4591 rather than "infixl" or "infixr";
  4592 
  4593 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  4594 sort constraint specifications in type inference; e.g. "x::_::foo"
  4595 ensures that the type of "x" is of sort "foo" (but not necessarily a
  4596 type variable);
  4597 
  4598 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  4599 control output of nested => (types); the default behavior is
  4600 "type_brackets";
  4601 
  4602 * Pure/syntax: builtin parse translation for "_constify" turns valued
  4603 tokens into AST constants;
  4604 
  4605 * Pure/syntax: prefer later declarations of translations and print
  4606 translation functions; potential INCOMPATIBILITY: need to reverse
  4607 multiple declarations for same syntax element constant;
  4608 
  4609 * Pure/show_hyps reset by default (in accordance to existing Isar
  4610 practice);
  4611 
  4612 * Provers/classical: renamed addaltern to addafter, addSaltern to
  4613 addSafter;
  4614 
  4615 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  4616 as well;
  4617 
  4618 * system: tested support for MacOS X; should be able to get Isabelle +
  4619 Proof General to work in a plain Terminal after installing Poly/ML
  4620 (e.g. from the Isabelle distribution area) and GNU bash alone
  4621 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  4622 support requires further installations, e.g. from
  4623 http://fink.sourceforge.net/);
  4624 
  4625 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  4626 
  4627 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  4628 of 40 MB), cf. ML_OPTIONS;
  4629 
  4630 * system: Proof General keywords specification is now part of the
  4631 Isabelle distribution (see etc/isar-keywords.el);
  4632 
  4633 * system: support for persistent Proof General sessions (refrain from
  4634 outdating all loaded theories on startup); user may create writable
  4635 logic images like this: ``isabelle -q HOL Test'';
  4636 
  4637 * system: smart selection of Isabelle process versus Isabelle
  4638 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  4639 run both "isabelle" and "Isabelle" even if file names are badly
  4640 damaged (executable inspects the case of the first letter of its own
  4641 name); added separate "isabelle-process" and "isabelle-interface";
  4642 
  4643 * system: refrain from any attempt at filtering input streams; no
  4644 longer support ``8bit'' encoding of old isabelle font, instead proper
  4645 iso-latin characters may now be used; the related isatools
  4646 "symbolinput" and "nonascii" have disappeared as well;
  4647 
  4648 * system: removed old "xterm" interface (the print modes "xterm" and
  4649 "xterm_color" are still available for direct use in a suitable
  4650 terminal);
  4651 
  4652 
  4653 
  4654 New in Isabelle99-2 (February 2001)
  4655 -----------------------------------
  4656 
  4657 *** Overview of INCOMPATIBILITIES ***
  4658 
  4659 * HOL: please note that theories in the Library and elsewhere often use the
  4660 new-style (Isar) format; to refer to their theorems in an ML script you must
  4661 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  4662 
  4663 * HOL: inductive package no longer splits induction rule aggressively,
  4664 but only as far as specified by the introductions given; the old
  4665 format may be recovered via ML function complete_split_rule or attribute
  4666 'split_rule (complete)';
  4667 
  4668 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  4669 gfp_Tarski to gfp_unfold;
  4670 
  4671 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  4672 
  4673 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  4674 relation); infix "^^" has been renamed "``"; infix "``" has been
  4675 renamed "`"; "univalent" has been renamed "single_valued";
  4676 
  4677 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  4678 operation;
  4679 
  4680 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  4681 
  4682 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  4683 
  4684 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  4685 consequence, it is no longer monotonic wrt. the local goal context
  4686 (which is now passed through the inductive cases);
  4687 
  4688 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  4689 \<gg> to \<ggreater>;
  4690 
  4691 
  4692 *** Document preparation ***
  4693 
  4694 * \isabellestyle{NAME} selects version of Isabelle output (currently
  4695 available: are "it" for near math-mode best-style output, "sl" for
  4696 slanted text style, and "tt" for plain type-writer; if no
  4697 \isabellestyle command is given, output is according to slanted
  4698 type-writer);
  4699 
  4700 * support sub/super scripts (for single symbols only), input syntax is
  4701 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  4702 
  4703 * some more standard symbols; see Appendix A of the system manual for
  4704 the complete list of symbols defined in isabellesym.sty;
  4705 
  4706 * improved isabelle style files; more abstract symbol implementation
  4707 (should now use \isamath{...} and \isatext{...} in custom symbol
  4708 definitions);
  4709 
  4710 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  4711 state; Note that presentation of goal states does not conform to
  4712 actual human-readable proof documents.  Please do not include goal
  4713 states into document output unless you really know what you are doing!
  4714 
  4715 * proper indentation of antiquoted output with proportional LaTeX
  4716 fonts;
  4717 
  4718 * no_document ML operator temporarily disables LaTeX document
  4719 generation;
  4720 
  4721 * isatool unsymbolize tunes sources for plain ASCII communication;
  4722 
  4723 
  4724 *** Isar ***
  4725 
  4726 * Pure: Isar now suffers initial goal statements to contain unbound
  4727 schematic variables (this does not conform to actual readable proof
  4728 documents, due to unpredictable outcome and non-compositional proof
  4729 checking); users who know what they are doing may use schematic goals
  4730 for Prolog-style synthesis of proven results;
  4731 
  4732 * Pure: assumption method (an implicit finishing) now handles actual
  4733 rules as well;
  4734 
  4735 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  4736 initial goal, declare "that" only as Pure intro (only for single
  4737 steps); the "that" rule assumption may now be involved in implicit
  4738 finishing, thus ".." becomes a feasible for trivial obtains;
  4739 
  4740 * Pure: default proof step now includes 'intro_classes'; thus trivial
  4741 instance proofs may be performed by "..";
  4742 
  4743 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  4744 statements as well;
  4745 
  4746 * Pure: more robust selection of calculational rules;
  4747 
  4748 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  4749 rule (as well as the assumption rule);
  4750 
  4751 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  4752 lemmas, using the graph browser tool;
  4753 
  4754 * Pure: predict failure of "show" in interactive mode;
  4755 
  4756 * Pure: 'thms_containing' now takes actual terms as arguments;
  4757 
  4758 * HOL: improved method 'induct' --- now handles non-atomic goals
  4759 (potential INCOMPATIBILITY); tuned error handling;
  4760 
  4761 * HOL: cases and induct rules now provide explicit hints about the
  4762 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  4763 any remaining facts are inserted into the goal verbatim;
  4764 
  4765 * HOL: local contexts (aka cases) may now contain term bindings as
  4766 well; the 'cases' and 'induct' methods new provide a ?case binding for
  4767 the result to be shown in each case;
  4768 
  4769 * HOL: added 'recdef_tc' command;
  4770 
  4771 * isatool convert assists in eliminating legacy ML scripts;
  4772 
  4773 
  4774 *** HOL ***
  4775 
  4776 * HOL/Library: a collection of generic theories to be used together
  4777 with main HOL; the theory loader path already includes this directory
  4778 by default; the following existing theories have been moved here:
  4779 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  4780 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  4781 
  4782 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  4783 modelling and verification task performed in Isabelle/HOL +
  4784 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  4785 
  4786 * HOL/Algebra: special summation operator SUM no longer exists, it has
  4787 been replaced by setsum; infix 'assoc' now has priority 50 (like
  4788 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  4789 'domain', this makes the theory consistent with mathematical
  4790 literature;
  4791 
  4792 * HOL basics: added overloaded operations "inverse" and "divide"
  4793 (infix "/"), syntax for generic "abs" operation, generic summation
  4794 operator \<Sum>;
  4795 
  4796 * HOL/typedef: simplified package, provide more useful rules (see also
  4797 HOL/subset.thy);
  4798 
  4799 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  4800 now expressed as a proper nested rule (old-style tactic scripts may
  4801 require atomize_strip_tac to cope with non-atomic premises);
  4802 
  4803 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  4804 to "split_conv" (old name still available for compatibility);
  4805 
  4806 * HOL: improved concrete syntax for strings (e.g. allows translation
  4807 rules with string literals);
  4808 
  4809 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  4810  and Fleuriot's mechanization of analysis, including the transcendental
  4811  functions for the reals;
  4812 
  4813 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  4814 
  4815 
  4816 *** CTT ***
  4817 
  4818 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  4819 "lam" is displayed as TWO lambda-symbols
  4820 
  4821 * CTT: theory Main now available, containing everything (that is, Bool
  4822 and Arith);
  4823 
  4824 
  4825 *** General ***
  4826 
  4827 * Pure: the Simplifier has been implemented properly as a derived rule
  4828 outside of the actual kernel (at last!); the overall performance
  4829 penalty in practical applications is about 50%, while reliability of
  4830 the Isabelle inference kernel has been greatly improved;
  4831 
  4832 * print modes "brackets" and "no_brackets" control output of nested =>
  4833 (types) and ==> (props); the default behaviour is "brackets";
  4834 
  4835 * Provers: fast_tac (and friends) now handle actual object-logic rules
  4836 as assumptions as well;
  4837 
  4838 * system: support Poly/ML 4.0;
  4839 
  4840 * system: isatool install handles KDE version 1 or 2;
  4841 
  4842 
  4843 
  4844 New in Isabelle99-1 (October 2000)
  4845 ----------------------------------
  4846 
  4847 *** Overview of INCOMPATIBILITIES ***
  4848 
  4849 * HOL: simplification of natural numbers is much changed; to partly
  4850 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  4851 issue the following ML commands:
  4852 
  4853   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  4854   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  4855 
  4856 * HOL: simplification no longer dives into case-expressions; this is
  4857 controlled by "t.weak_case_cong" for each datatype t;
  4858 
  4859 * HOL: nat_less_induct renamed to less_induct;
  4860 
  4861 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  4862 fixsome to patch .thy and .ML sources automatically;
  4863 
  4864   select_equality  -> some_equality
  4865   select_eq_Ex     -> some_eq_ex
  4866   selectI2EX       -> someI2_ex
  4867   selectI2         -> someI2
  4868   selectI          -> someI
  4869   select1_equality -> some1_equality
  4870   Eps_sym_eq       -> some_sym_eq_trivial
  4871   Eps_eq           -> some_eq_trivial
  4872 
  4873 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  4874 
  4875 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  4876 instead);
  4877 
  4878 * HOL: the recursion equations generated by 'recdef' are now called
  4879 f.simps instead of f.rules;
  4880 
  4881 * HOL: qed_spec_mp now also handles bounded ALL as well;
  4882 
  4883 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  4884 sometimes be needed;
  4885 
  4886 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  4887 
  4888 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  4889 
  4890 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  4891 product is now "<*>" instead of "Times"; the lexicographic product is
  4892 now "<*lex*>" instead of "**";
  4893 
  4894 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  4895 of main HOL, but was unused); better use HOL's datatype package;
  4896 
  4897 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  4898 the old syntax may be recovered as follows:
  4899 
  4900   syntax (symbols)
  4901     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  4902       (infixl "\\<oplus>" 100)
  4903 
  4904 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  4905 
  4906 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  4907 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  4908 internally;
  4909 
  4910 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  4911 changed from A/r to A//r;
  4912 
  4913 * ZF: new treatment of arithmetic (nat & int) may break some old
  4914 proofs;
  4915 
  4916 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  4917 rulify -> rule_format, elimify -> elim_format, ...);
  4918 
  4919 * Isar/Provers: intro/elim/dest attributes changed; renamed
  4920 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  4921 should have to change intro!! to intro? only); replaced "delrule" by
  4922 "rule del";
  4923 
  4924 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  4925 
  4926 * Provers: strengthened force_tac by using new first_best_tac;
  4927 
  4928 * LaTeX document preparation: several changes of isabelle.sty (see
  4929 lib/texinputs);
  4930 
  4931 
  4932 *** Document preparation ***
  4933 
  4934 * formal comments (text blocks etc.) in new-style theories may now
  4935 contain antiquotations of thm/prop/term/typ/text to be presented
  4936 according to latex print mode; concrete syntax is like this:
  4937 @{term[show_types] "f(x) = a + x"};
  4938 
  4939 * isatool mkdir provides easy setup of Isabelle session directories,
  4940 including proper document sources;
  4941 
  4942 * generated LaTeX sources are now deleted after successful run
  4943 (isatool document -c); may retain a copy somewhere else via -D option
  4944 of isatool usedir;
  4945 
  4946 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  4947 style files, achieving self-contained LaTeX sources and simplifying
  4948 LaTeX debugging;
  4949 
  4950 * old-style theories now produce (crude) LaTeX output as well;
  4951 
  4952 * browser info session directories are now self-contained (may be put
  4953 on WWW server seperately); improved graphs of nested sessions; removed
  4954 graph for 'all sessions';
  4955 
  4956 * several improvements in isabelle style files; \isabellestyle{it}
  4957 produces fake math mode output; \isamarkupheader is now \section by
  4958 default; see lib/texinputs/isabelle.sty etc.;
  4959 
  4960 
  4961 *** Isar ***
  4962 
  4963 * Isar/Pure: local results and corresponding term bindings are now
  4964 subject to Hindley-Milner polymorphism (similar to ML); this
  4965 accommodates incremental type-inference very nicely;
  4966 
  4967 * Isar/Pure: new derived language element 'obtain' supports
  4968 generalized existence reasoning;
  4969 
  4970 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  4971 support accumulation of results, without applying any rules yet;
  4972 useful to collect intermediate results without explicit name
  4973 references, and for use with transitivity rules with more than 2
  4974 premises;
  4975 
  4976 * Isar/Pure: scalable support for case-analysis type proofs: new
  4977 'case' language element refers to local contexts symbolically, as
  4978 produced by certain proof methods; internally, case names are attached
  4979 to theorems as "tags";
  4980 
  4981 * Isar/Pure: theory command 'hide' removes declarations from
  4982 class/type/const name spaces;
  4983 
  4984 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  4985 indicate potential overloading;
  4986 
  4987 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  4988 
  4989 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  4990 "{a,b,c}" instead of {a,b,c};
  4991 
  4992 * Isar/Pure now provides its own version of intro/elim/dest
  4993 attributes; useful for building new logics, but beware of confusion
  4994 with the version in Provers/classical;
  4995 
  4996 * Isar/Pure: the local context of (non-atomic) goals is provided via
  4997 case name 'antecedent';
  4998 
  4999 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  5000 to the current context is now done automatically);
  5001 
  5002 * Isar/Pure: theory command 'method_setup' provides a simple interface
  5003 for definining proof methods in ML;
  5004 
  5005 * Isar/Provers: intro/elim/dest attributes changed; renamed
  5006 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  5007 most cases, one should have to change intro!! to intro? only);
  5008 replaced "delrule" by "rule del";
  5009 
  5010 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  5011 'symmetric' attribute (the latter supercedes [RS sym]);
  5012 
  5013 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  5014 method modifier); 'simp' method: 'only:' modifier removes loopers as
  5015 well (including splits);
  5016 
  5017 * Isar/Provers: Simplifier and Classical methods now support all kind
  5018 of modifiers used in the past, including 'cong', 'iff', etc.
  5019 
  5020 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  5021 of Simplifier and Classical reasoner);
  5022 
  5023 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  5024 now support named cases; major packages (inductive, datatype, primrec,
  5025 recdef) support case names and properly name parameters;
  5026 
  5027 * Isar/HOL: new transitivity rules for substitution in inequalities --
  5028 monotonicity conditions are extracted to be proven at end of
  5029 calculations;
  5030 
  5031 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  5032 method anyway;
  5033 
  5034 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  5035 split_if split_if_asm; datatype package provides theorems foo.splits =
  5036 foo.split foo.split_asm for each datatype;
  5037 
  5038 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  5039 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  5040 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  5041 use "(cases (simplified))" method in proper proof texts);
  5042 
  5043 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  5044 
  5045 * Isar: names of theorems etc. may be natural numbers as well;
  5046 
  5047 * Isar: 'pr' command: optional arguments for goals_limit and
  5048 ProofContext.prems_limit; no longer prints theory contexts, but only
  5049 proof states;
  5050 
  5051 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  5052 additional print modes to be specified; e.g. "pr(latex)" will print
  5053 proof state according to the Isabelle LaTeX style;
  5054 
  5055 * Isar: improved support for emulating tactic scripts, including proof
  5056 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  5057 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  5058 (for HOL datatypes);
  5059 
  5060 * Isar: simplified (more robust) goal selection of proof methods: 1st
  5061 goal, all goals, or explicit goal specifier (tactic emulation); thus
  5062 'proof method scripts' have to be in depth-first order;
  5063 
  5064 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  5065 
  5066 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  5067 should instead use individual commands for printing items
  5068 (print_commands, print_methods etc.);
  5069 
  5070 * Isar: added 'nothing' --- the empty list of theorems;
  5071 
  5072 
  5073 *** HOL ***
  5074 
  5075 * HOL/MicroJava: formalization of a fragment of Java, together with a
  5076 corresponding virtual machine and a specification of its bytecode
  5077 verifier and a lightweight bytecode verifier, including proofs of
  5078 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  5079 Cornelia Pusch (see also the homepage of project Bali at
  5080 http://isabelle.in.tum.de/Bali/);
  5081 
  5082 * HOL/Algebra: new theory of rings and univariate polynomials, by
  5083 Clemens Ballarin;
  5084 
  5085 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  5086 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  5087 Rasmussen;
  5088 
  5089 * HOL/Lattice: fundamental concepts of lattice theory and order
  5090 structures, including duals, properties of bounds versus algebraic
  5091 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  5092 Theorem for complete lattices etc.; may also serve as a demonstration
  5093 for abstract algebraic reasoning using axiomatic type classes, and
  5094 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  5095 
  5096 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  5097 von Oheimb;
  5098 
  5099 * HOL/IMPP: extension of IMP with local variables and mutually
  5100 recursive procedures, by David von Oheimb;
  5101 
  5102 * HOL/Lambda: converted into new-style theory and document;
  5103 
  5104 * HOL/ex/Multiquote: example of multiple nested quotations and
  5105 anti-quotations -- basically a generalized version of de-Bruijn
  5106 representation; very useful in avoiding lifting of operations;
  5107 
  5108 * HOL/record: added general record equality rule to simpset; fixed
  5109 select-update simplification procedure to handle extended records as
  5110 well; admit "r" as field name;
  5111 
  5112 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  5113 other numeric types and also as the identity of groups, rings, etc.;
  5114 
  5115 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  5116 Types nat and int belong to this axclass;
  5117 
  5118 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  5119    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  5120    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  5121   two terms #m*u and #n*u are replaced by #(m+n)*u
  5122     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  5123   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  5124     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  5125 
  5126 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  5127 powerful prover for predicate logic but knows nothing of clasets; see
  5128 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  5129 
  5130 * HOL: new version of "case_tac" subsumes both boolean case split and
  5131 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  5132 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  5133 
  5134 * HOL: simplification no longer dives into case-expressions: only the
  5135 selector expression is simplified, but not the remaining arms; to
  5136 enable full simplification of case-expressions for datatype t, you may
  5137 remove t.weak_case_cong from the simpset, either globally (Delcongs
  5138 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  5139 
  5140 * HOL/recdef: the recursion equations generated by 'recdef' for
  5141 function 'f' are now called f.simps instead of f.rules; if all
  5142 termination conditions are proved automatically, these simplification
  5143 rules are added to the simpset, as in primrec; rules may be named
  5144 individually as well, resulting in a separate list of theorems for
  5145 each equation;
  5146 
  5147 * HOL/While is a new theory that provides a while-combinator. It
  5148 permits the definition of tail-recursive functions without the
  5149 provision of a termination measure. The latter is necessary once the
  5150 invariant proof rule for while is applied.
  5151 
  5152 * HOL: new (overloaded) notation for the set of elements below/above
  5153 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  5154 
  5155 * HOL: theorems impI, allI, ballI bound as "strip";
  5156 
  5157 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  5158 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  5159 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  5160 
  5161 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  5162 
  5163 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  5164 main HOL, but was unused);
  5165 
  5166 * HOL: fewer consts declared as global (e.g. have to refer to
  5167 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  5168 
  5169 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  5170 in case of overlap with user translations (e.g. judgements over
  5171 tuples); (note that the underlying logical represenation is still
  5172 bogus);
  5173 
  5174 
  5175 *** ZF ***
  5176 
  5177 * ZF: simplification automatically cancels common terms in arithmetic
  5178 expressions over nat and int;
  5179 
  5180 * ZF: new treatment of nat to minimize type-checking: all operators
  5181 coerce their operands to a natural number using the function natify,
  5182 making the algebraic laws unconditional;
  5183 
  5184 * ZF: as above, for int: operators coerce their operands to an integer
  5185 using the function intify;
  5186 
  5187 * ZF: the integer library now contains many of the usual laws for the
  5188 orderings, including $<=, and monotonicity laws for $+ and $*;
  5189 
  5190 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  5191 simplification;
  5192 
  5193 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  5194 to the simplifier and classical reasoner simultaneously;
  5195 
  5196 
  5197 *** General ***
  5198 
  5199 * Provers: blast_tac now handles actual object-logic rules as
  5200 assumptions; note that auto_tac uses blast_tac internally as well;
  5201 
  5202 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  5203 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  5204 
  5205 * Provers: delrules now handles destruct rules as well (no longer need
  5206 explicit make_elim);
  5207 
  5208 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  5209   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  5210 use instead the strong form,
  5211   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  5212 in HOL, FOL and ZF the function cla_make_elim will create such rules
  5213 from destruct-rules;
  5214 
  5215 * Provers: Simplifier.easy_setup provides a fast path to basic
  5216 Simplifier setup for new object-logics;
  5217 
  5218 * Pure: AST translation rules no longer require constant head on LHS;
  5219 
  5220 * Pure: improved name spaces: ambiguous output is qualified; support
  5221 for hiding of names;
  5222 
  5223 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  5224 XSYMBOL_HOME; no longer need to do manual configuration in most
  5225 situations;
  5226 
  5227 * system: compression of ML heaps images may now be controlled via -c
  5228 option of isabelle and isatool usedir (currently only observed by
  5229 Poly/ML);
  5230 
  5231 * system: isatool installfonts may handle X-Symbol fonts as well (very
  5232 useful for remote X11);
  5233 
  5234 * system: provide TAGS file for Isabelle sources;
  5235 
  5236 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  5237 order;
  5238 
  5239 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  5240 timing flag supersedes proof_timing and Toplevel.trace;
  5241 
  5242 * ML: new combinators |>> and |>>> for incremental transformations
  5243 with secondary results (e.g. certain theory extensions):
  5244 
  5245 * ML: PureThy.add_defs gets additional argument to indicate potential
  5246 overloading (usually false);
  5247 
  5248 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  5249 results;
  5250 
  5251 
  5252 
  5253 New in Isabelle99 (October 1999)
  5254 --------------------------------
  5255 
  5256 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  5257 
  5258 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  5259 are no longer simplified.  (This allows the simplifier to unfold recursive
  5260 functional programs.)  To restore the old behaviour, declare
  5261 
  5262     Delcongs [if_weak_cong];
  5263 
  5264 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  5265 complement;
  5266 
  5267 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  5268 
  5269 * HOL/datatype: mutual_induct_tac no longer exists --
  5270   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  5271 
  5272 * HOL/typedef: fixed type inference for representing set; type
  5273 arguments now have to occur explicitly on the rhs as type constraints;
  5274 
  5275 * ZF: The con_defs part of an inductive definition may no longer refer
  5276 to constants declared in the same theory;
  5277 
  5278 * HOL, ZF: the function mk_cases, generated by the inductive
  5279 definition package, has lost an argument.  To simplify its result, it
  5280 uses the default simpset instead of a supplied list of theorems.
  5281 
  5282 * HOL/List: the constructors of type list are now Nil and Cons;
  5283 
  5284 * Simplifier: the type of the infix ML functions
  5285         setSSolver addSSolver setSolver addSolver
  5286 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  5287 for packaging solvers. A solver is created via
  5288         mk_solver: string -> (thm list -> int -> tactic) -> solver
  5289 where the string argument is only a comment.
  5290 
  5291 
  5292 *** Proof tools ***
  5293 
  5294 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  5295 decision procedure for linear arithmetic. Currently it is used for
  5296 types `nat', `int', and `real' in HOL (see below); it can, should and
  5297 will be instantiated for other types and logics as well.
  5298 
  5299 * The simplifier now accepts rewrite rules with flexible heads, eg
  5300      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  5301   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  5302   matching.
  5303 
  5304 
  5305 *** General ***
  5306 
  5307 * New Isabelle/Isar subsystem provides an alternative to traditional
  5308 tactical theorem proving; together with the ProofGeneral/isar user
  5309 interface it offers an interactive environment for developing human
  5310 readable proof documents (Isar == Intelligible semi-automated
  5311 reasoning); for further information see isatool doc isar-ref,
  5312 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  5313 
  5314 * improved and simplified presentation of theories: better HTML markup
  5315 (including colors), graph views in several sizes; isatool usedir now
  5316 provides a proper interface for user theories (via -P option); actual
  5317 document preparation based on (PDF)LaTeX is available as well (for
  5318 new-style theories only); see isatool doc system for more information;
  5319 
  5320 * native support for Proof General, both for classic Isabelle and
  5321 Isabelle/Isar;
  5322 
  5323 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  5324 using the graph browser tool;
  5325 
  5326 * Isabelle manuals now also available as PDF;
  5327 
  5328 * theory loader rewritten from scratch (may not be fully
  5329 bug-compatible); old loadpath variable has been replaced by show_path,
  5330 add_path, del_path, reset_path functions; new operations such as
  5331 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  5332 isatool doc ref);
  5333 
  5334 * improved isatool install: option -k creates KDE application icon,
  5335 option -p DIR installs standalone binaries;
  5336 
  5337 * added ML_PLATFORM setting (useful for cross-platform installations);
  5338 more robust handling of platform specific ML images for SML/NJ;
  5339 
  5340 * the settings environment is now statically scoped, i.e. it is never
  5341 created again in sub-processes invoked from isabelle, isatool, or
  5342 Isabelle;
  5343 
  5344 * path element specification '~~' refers to '$ISABELLE_HOME';
  5345 
  5346 * in locales, the "assumes" and "defines" parts may be omitted if
  5347 empty;
  5348 
  5349 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  5350 long arrows);
  5351 
  5352 * new print_mode "HTML";
  5353 
  5354 * new flag show_tags controls display of tags of theorems (which are
  5355 basically just comments that may be attached by some tools);
  5356 
  5357 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  5358 mode and goal output format:
  5359 
  5360 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  5361 244c244
  5362 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  5363 ---
  5364 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  5365 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  5366 181c181
  5367 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  5368 ---
  5369 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  5370 
  5371 * function bind_thms stores lists of theorems (cf. bind_thm);
  5372 
  5373 * new shorthand tactics ftac, eatac, datac, fatac;
  5374 
  5375 * qed (and friends) now accept "" as result name; in that case the
  5376 theorem is not stored, but proper checks and presentation of the
  5377 result still apply;
  5378 
  5379 * theorem database now also indexes constants "Trueprop", "all",
  5380 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  5381 
  5382 
  5383 *** HOL ***
  5384 
  5385 ** HOL arithmetic **
  5386 
  5387 * There are now decision procedures for linear arithmetic over nat and
  5388 int:
  5389 
  5390 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  5391 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  5392 are treated as atomic; subformulae not involving type `nat' or `int'
  5393 are ignored; quantified subformulae are ignored unless they are
  5394 positive universal or negative existential. The tactic has to be
  5395 invoked by hand and can be a little bit slow. In particular, the
  5396 running time is exponential in the number of occurrences of `min' and
  5397 `max', and `-' on `nat'.
  5398 
  5399 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  5400 (negated) (in)equalities among the premises and the conclusion into
  5401 account (i.e. no compound formulae) and does not know about `min' and
  5402 `max', and `-' on `nat'. It is fast and is used automatically by the
  5403 simplifier.
  5404 
  5405 NB: At the moment, these decision procedures do not cope with mixed
  5406 nat/int formulae where the two parts interact, such as `m < n ==>
  5407 int(m) < int(n)'.
  5408 
  5409 * HOL/Numeral provides a generic theory of numerals (encoded
  5410 efficiently as bit strings); setup for types nat/int/real is in place;
  5411 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  5412 int, existing theories and proof scripts may require a few additional
  5413 type constraints;
  5414 
  5415 * integer division and remainder can now be performed on constant
  5416 arguments;
  5417 
  5418 * many properties of integer multiplication, division and remainder
  5419 are now available;
  5420 
  5421 * An interface to the Stanford Validity Checker (SVC) is available through the
  5422 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  5423 are proved automatically.  SVC must be installed separately, and its results
  5424 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  5425 invocation of the underlying oracle).  For SVC see
  5426   http://verify.stanford.edu/SVC
  5427 
  5428 * IsaMakefile: the HOL-Real target now builds an actual image;
  5429 
  5430 
  5431 ** HOL misc **
  5432 
  5433 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  5434 (in Isabelle/Isar) -- by Gertrud Bauer;
  5435 
  5436 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  5437 analysis for assembly languages with subtypes;
  5438 
  5439 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  5440 -- avoids syntactic ambiguities and treats state, transition, and
  5441 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  5442 changed syntax and (many) tactics;
  5443 
  5444 * HOL/inductive: Now also handles more general introduction rules such
  5445   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  5446   theorems are now maintained within the theory (maintained via the
  5447   "mono" attribute);
  5448 
  5449 * HOL/datatype: Now also handles arbitrarily branching datatypes
  5450   (using function types) such as
  5451 
  5452   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  5453 
  5454 * HOL/record: record_simproc (part of the default simpset) takes care
  5455 of selectors applied to updated records; record_split_tac is no longer
  5456 part of the default claset; update_defs may now be removed from the
  5457 simpset in many cases; COMPATIBILITY: old behavior achieved by
  5458 
  5459   claset_ref () := claset() addSWrapper record_split_wrapper;
  5460   Delsimprocs [record_simproc]
  5461 
  5462 * HOL/typedef: fixed type inference for representing set; type
  5463 arguments now have to occur explicitly on the rhs as type constraints;
  5464 
  5465 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  5466 names rather than an ML expression;
  5467 
  5468 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  5469 supplied later.  Program schemes can be defined, such as
  5470     "While B C s = (if B s then While B C (C s) else s)"
  5471 where the well-founded relation can be chosen after B and C have been given.
  5472 
  5473 * HOL/List: the constructors of type list are now Nil and Cons;
  5474 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  5475 course, ML tools referring to List.list.op # etc. have to be adapted;
  5476 
  5477 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  5478 disabled by default; run isabelle with option -m HOL to get back to
  5479 the original Gordon/HOL-style output;
  5480 
  5481 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  5482 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  5483 
  5484 * HOL basic syntax simplified (more orthogonal): all variants of
  5485 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  5486 Eps operator is provided as well: "SOME x. P[x]";
  5487 
  5488 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  5489 
  5490 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  5491 thus available for user theories;
  5492 
  5493 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  5494 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  5495 time;
  5496 
  5497 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  5498 several times and then mp;
  5499 
  5500 
  5501 *** LK ***
  5502 
  5503 * the notation <<...>> is now available as a notation for sequences of
  5504 formulas;
  5505 
  5506 * the simplifier is now installed
  5507 
  5508 * the axiom system has been generalized (thanks to Soren Heilmann)
  5509 
  5510 * the classical reasoner now has a default rule database
  5511 
  5512 
  5513 *** ZF ***
  5514 
  5515 * new primrec section allows primitive recursive functions to be given
  5516 directly (as in HOL) over datatypes and the natural numbers;
  5517 
  5518 * new tactics induct_tac and exhaust_tac for induction (or case
  5519 analysis) over datatypes and the natural numbers;
  5520 
  5521 * the datatype declaration of type T now defines the recursor T_rec;
  5522 
  5523 * simplification automatically does freeness reasoning for datatype
  5524 constructors;
  5525 
  5526 * automatic type-inference, with AddTCs command to insert new
  5527 type-checking rules;
  5528 
  5529 * datatype introduction rules are now added as Safe Introduction rules
  5530 to the claset;
  5531 
  5532 * the syntax "if P then x else y" is now available in addition to
  5533 if(P,x,y);
  5534 
  5535 
  5536 *** Internal programming interfaces ***
  5537 
  5538 * tuned simplifier trace output; new flag debug_simp;
  5539 
  5540 * structures Vartab / Termtab (instances of TableFun) offer efficient
  5541 tables indexed by indexname_ord / term_ord (compatible with aconv);
  5542 
  5543 * AxClass.axclass_tac lost the theory argument;
  5544 
  5545 * tuned current_goals_markers semantics: begin / end goal avoids
  5546 printing empty lines;
  5547 
  5548 * removed prs and prs_fn hook, which was broken because it did not
  5549 include \n in its semantics, forcing writeln to add one
  5550 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  5551 string -> unit if you really want to output text without newline;
  5552 
  5553 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  5554 plain output, interface builders may have to enable 'isabelle_font'
  5555 mode to get Isabelle font glyphs as before;
  5556 
  5557 * refined token_translation interface; INCOMPATIBILITY: output length
  5558 now of type real instead of int;
  5559 
  5560 * theory loader actions may be traced via new ThyInfo.add_hook
  5561 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  5562 your own database of information attached to *whole* theories -- as
  5563 opposed to intra-theory data slots offered via TheoryDataFun;
  5564 
  5565 * proper handling of dangling sort hypotheses (at last!);
  5566 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  5567 extra sort hypotheses that can be witnessed from the type signature;
  5568 the force_strip_shyps flag is gone, any remaining shyps are simply
  5569 left in the theorem (with a warning issued by strip_shyps_warning);
  5570 
  5571 
  5572 
  5573 New in Isabelle98-1 (October 1998)
  5574 ----------------------------------
  5575 
  5576 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  5577 
  5578 * several changes of automated proof tools;
  5579 
  5580 * HOL: major changes to the inductive and datatype packages, including
  5581 some minor incompatibilities of theory syntax;
  5582 
  5583 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  5584 called `inj_on';
  5585 
  5586 * HOL: removed duplicate thms in Arith:
  5587   less_imp_add_less  should be replaced by  trans_less_add1
  5588   le_imp_add_le      should be replaced by  trans_le_add1
  5589 
  5590 * HOL: unary minus is now overloaded (new type constraints may be
  5591 required);
  5592 
  5593 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  5594 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  5595 now taken as an integer constant.
  5596 
  5597 * Pure: ML function 'theory_of' renamed to 'theory';
  5598 
  5599 
  5600 *** Proof tools ***
  5601 
  5602 * Simplifier:
  5603   1. Asm_full_simp_tac is now more aggressive.
  5604      1. It will sometimes reorient premises if that increases their power to
  5605         simplify.
  5606      2. It does no longer proceed strictly from left to right but may also
  5607         rotate premises to achieve further simplification.
  5608      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  5609      old Asm_full_simp_tac in that it does not rotate premises.
  5610   2. The simplifier now knows a little bit about nat-arithmetic.
  5611 
  5612 * Classical reasoner: wrapper mechanism for the classical reasoner now
  5613 allows for selected deletion of wrappers, by introduction of names for
  5614 wrapper functionals.  This implies that addbefore, addSbefore,
  5615 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  5616 and that adding two tactics with the same name overwrites the first
  5617 one (emitting a warning).
  5618   type wrapper = (int -> tactic) -> (int -> tactic)
  5619   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  5620   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  5621   delWrapper, delSWrapper: claset *  string            -> claset
  5622   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  5623 
  5624 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  5625 semantics; addbefore now affects only the unsafe part of step_tac
  5626 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  5627 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  5628 by Force_tac;
  5629 
  5630 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  5631 compWrapper; added safe wrapper (and access functions for it);
  5632 
  5633 * HOL/split_all_tac is now much faster and fails if there is nothing
  5634 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  5635 and the names of the automatically generated variables have changed.
  5636 split_all_tac has moved within claset() from unsafe wrappers to safe
  5637 wrappers, which means that !!-bound variables are split much more
  5638 aggressively, and safe_tac and clarify_tac now split such variables.
  5639 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  5640 Note: the same holds for record_split_tac, which does the job of
  5641 split_all_tac for record fields.
  5642 
  5643 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  5644 permanently to the default simpset using Addsplits just like
  5645 Addsimps. They can be removed via Delsplits just like
  5646 Delsimps. Lower-case versions are also available.
  5647 
  5648 * HOL/Simplifier: The rule split_if is now part of the default
  5649 simpset. This means that the simplifier will eliminate all occurrences
  5650 of if-then-else in the conclusion of a goal. To prevent this, you can
  5651 either remove split_if completely from the default simpset by
  5652 `Delsplits [split_if]' or remove it in a specific call of the
  5653 simplifier using `... delsplits [split_if]'.  You can also add/delete
  5654 other case splitting rules to/from the default simpset: every datatype
  5655 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  5656 t is the name of the datatype).
  5657 
  5658 * Classical reasoner / Simplifier combination: new force_tac (and
  5659 derivatives Force_tac, force) combines rewriting and classical
  5660 reasoning (and whatever other tools) similarly to auto_tac, but is
  5661 aimed to solve the given subgoal completely.
  5662 
  5663 
  5664 *** General ***
  5665 
  5666 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  5667 and `goalw': the theory is no longer needed as an explicit argument -
  5668 the current theory context is used; assumptions are no longer returned
  5669 at the ML-level unless one of them starts with ==> or !!; it is
  5670 recommended to convert to these new commands using isatool fixgoal
  5671 (backup your sources first!);
  5672 
  5673 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  5674 the current theory context, and 'theory' to lookup stored theories;
  5675 
  5676 * new theory section 'locale' for declaring constants, assumptions and
  5677 definitions that have local scope;
  5678 
  5679 * new theory section 'nonterminals' for purely syntactic types;
  5680 
  5681 * new theory section 'setup' for generic ML setup functions
  5682 (e.g. package initialization);
  5683 
  5684 * the distribution now includes Isabelle icons: see
  5685 lib/logo/isabelle-{small,tiny}.xpm;
  5686 
  5687 * isatool install - install binaries with absolute references to
  5688 ISABELLE_HOME/bin;
  5689 
  5690 * isatool logo -- create instances of the Isabelle logo (as EPS);
  5691 
  5692 * print mode 'emacs' reserved for Isamode;
  5693 
  5694 * support multiple print (ast) translations per constant name;
  5695 
  5696 * theorems involving oracles are now printed with a suffixed [!];
  5697 
  5698 
  5699 *** HOL ***
  5700 
  5701 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  5702 
  5703 * HOL/inductive package reorganized and improved: now supports mutual
  5704 definitions such as
  5705 
  5706   inductive EVEN ODD
  5707     intrs
  5708       null "0 : EVEN"
  5709       oddI "n : EVEN ==> Suc n : ODD"
  5710       evenI "n : ODD ==> Suc n : EVEN"
  5711 
  5712 new theorem list "elims" contains an elimination rule for each of the
  5713 recursive sets; inductive definitions now handle disjunctive premises
  5714 correctly (also ZF);
  5715 
  5716 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  5717 "mutual_induct" no longer exists - the induction rule is always
  5718 contained in "induct";
  5719 
  5720 
  5721 * HOL/datatype package re-implemented and greatly improved: now
  5722 supports mutually recursive datatypes such as
  5723 
  5724   datatype
  5725     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  5726             | SUM ('a aexp) ('a aexp)
  5727             | DIFF ('a aexp) ('a aexp)
  5728             | NUM 'a
  5729   and
  5730     'a bexp = LESS ('a aexp) ('a aexp)
  5731             | AND ('a bexp) ('a bexp)
  5732             | OR ('a bexp) ('a bexp)
  5733 
  5734 as well as indirectly recursive datatypes such as
  5735 
  5736   datatype
  5737     ('a, 'b) term = Var 'a
  5738                   | App 'b ((('a, 'b) term) list)
  5739 
  5740 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  5741 induction on mutually / indirectly recursive datatypes.
  5742 
  5743 Primrec equations are now stored in theory and can be accessed via
  5744 <function_name>.simps.
  5745 
  5746 INCOMPATIBILITIES:
  5747 
  5748   - Theories using datatypes must now have theory Datatype as an
  5749     ancestor.
  5750   - The specific <typename>.induct_tac no longer exists - use the
  5751     generic induct_tac instead.
  5752   - natE has been renamed to nat.exhaust - use exhaust_tac
  5753     instead of res_inst_tac ... natE. Note that the variable
  5754     names in nat.exhaust differ from the names in natE, this
  5755     may cause some "fragile" proofs to fail.
  5756   - The theorems split_<typename>_case and split_<typename>_case_asm
  5757     have been renamed to <typename>.split and <typename>.split_asm.
  5758   - Since default sorts of type variables are now handled correctly,
  5759     some datatype definitions may have to be annotated with explicit
  5760     sort constraints.
  5761   - Primrec definitions no longer require function name and type
  5762     of recursive argument.
  5763 
  5764 Consider using isatool fixdatatype to adapt your theories and proof
  5765 scripts to the new package (backup your sources first!).
  5766 
  5767 
  5768 * HOL/record package: considerably improved implementation; now
  5769 includes concrete syntax for record types, terms, updates; theorems
  5770 for surjective pairing and splitting !!-bound record variables; proof
  5771 support is as follows:
  5772 
  5773   1) standard conversions (selectors or updates applied to record
  5774 constructor terms) are part of the standard simpset;
  5775 
  5776   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  5777 made part of standard simpset and claset via addIffs;
  5778 
  5779   3) a tactic for record field splitting (record_split_tac) is part of
  5780 the standard claset (addSWrapper);
  5781 
  5782 To get a better idea about these rules you may retrieve them via
  5783 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  5784 the name of your record type.
  5785 
  5786 The split tactic 3) conceptually simplifies by the following rule:
  5787 
  5788   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  5789 
  5790 Thus any record variable that is bound by meta-all will automatically
  5791 blow up into some record constructor term, consequently the
  5792 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  5793 solve record problems automatically.
  5794 
  5795 
  5796 * reorganized the main HOL image: HOL/Integ and String loaded by
  5797 default; theory Main includes everything;
  5798 
  5799 * automatic simplification of integer sums and comparisons, using cancellation;
  5800 
  5801 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  5802 
  5803 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  5804 
  5805 * many new identities for unions, intersections, set difference, etc.;
  5806 
  5807 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  5808 called split_if, split_split, split_sum_case and split_nat_case (to go
  5809 with add/delsplits);
  5810 
  5811 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  5812 (?x::unit) = (); this is made part of the default simpset, which COULD
  5813 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  5814 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  5815 unit_abs_eta_conv is added in order to counter the effect of
  5816 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  5817 %u.f();
  5818 
  5819 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  5820 makes more sense);
  5821 
  5822 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  5823   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  5824   disjointness reasoning but breaking a few old proofs.
  5825 
  5826 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  5827 to 'converse' from 'inverse' (for compatibility with ZF and some
  5828 literature);
  5829 
  5830 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  5831 the well-founded relation;
  5832 
  5833 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  5834     Compl A.  The "Compl" syntax remains available as input syntax for this
  5835     release ONLY.
  5836 
  5837 * HOL/Update: new theory of function updates:
  5838     f(a:=b) == %x. if x=a then b else f x
  5839 may also be iterated as in f(a:=b,c:=d,...);
  5840 
  5841 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  5842 
  5843 * HOL/List:
  5844   - new function list_update written xs[i:=v] that updates the i-th
  5845     list position. May also be iterated as in xs[i:=a,j:=b,...].
  5846   - new function `upt' written [i..j(] which generates the list
  5847     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  5848     bound write [i..j], which is a shorthand for [i..j+1(].
  5849   - new lexicographic orderings and corresponding wellfoundedness theorems.
  5850 
  5851 * HOL/Arith:
  5852   - removed 'pred' (predecessor) function;
  5853   - generalized some theorems about n-1;
  5854   - many new laws about "div" and "mod";
  5855   - new laws about greatest common divisors (see theory ex/Primes);
  5856 
  5857 * HOL/Relation: renamed the relational operator r^-1 "converse"
  5858 instead of "inverse";
  5859 
  5860 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  5861   of the multiset ordering;
  5862 
  5863 * directory HOL/Real: a construction of the reals using Dedekind cuts
  5864   (not included by default);
  5865 
  5866 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  5867 
  5868 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  5869   programs, i.e. different program variables may have different types.
  5870 
  5871 * calling (stac rew i) now fails if "rew" has no effect on the goal
  5872   [previously, this check worked only if the rewrite rule was unconditional]
  5873   Now rew can involve either definitions or equalities (either == or =).
  5874 
  5875 
  5876 *** ZF ***
  5877 
  5878 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  5879   only the theorems proved on ZF.ML;
  5880 
  5881 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  5882   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  5883   disjointness reasoning but breaking a few old proofs.
  5884 
  5885 * ZF/Update: new theory of function updates
  5886     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  5887   may also be iterated as in f(a:=b,c:=d,...);
  5888 
  5889 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  5890 
  5891 * calling (stac rew i) now fails if "rew" has no effect on the goal
  5892   [previously, this check worked only if the rewrite rule was unconditional]
  5893   Now rew can involve either definitions or equalities (either == or =).
  5894 
  5895 * case_tac provided for compatibility with HOL
  5896     (like the old excluded_middle_tac, but with subgoals swapped)
  5897 
  5898 
  5899 *** Internal programming interfaces ***
  5900 
  5901 * Pure: several new basic modules made available for general use, see
  5902 also src/Pure/README;
  5903 
  5904 * improved the theory data mechanism to support encapsulation (data
  5905 kind name replaced by private Object.kind, acting as authorization
  5906 key); new type-safe user interface via functor TheoryDataFun; generic
  5907 print_data function becomes basically useless;
  5908 
  5909 * removed global_names compatibility flag -- all theory declarations
  5910 are qualified by default;
  5911 
  5912 * module Pure/Syntax now offers quote / antiquote translation
  5913 functions (useful for Hoare logic etc. with implicit dependencies);
  5914 see HOL/ex/Antiquote for an example use;
  5915 
  5916 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  5917 cterm -> thm;
  5918 
  5919 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  5920 subgoal;
  5921 
  5922 * Display.print_goals function moved to Locale.print_goals;
  5923 
  5924 * standard print function for goals supports current_goals_markers
  5925 variable for marking begin of proof, end of proof, start of goal; the
  5926 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  5927 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  5928 for example;
  5929 
  5930 
  5931 
  5932 New in Isabelle98 (January 1998)
  5933 --------------------------------
  5934 
  5935 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  5936 
  5937 * changed lexical syntax of terms / types: dots made part of long
  5938 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  5939 
  5940 * simpset (and claset) reference variable replaced by functions
  5941 simpset / simpset_ref;
  5942 
  5943 * no longer supports theory aliases (via merge) and non-trivial
  5944 implicit merge of thms' signatures;
  5945 
  5946 * most internal names of constants changed due to qualified names;
  5947 
  5948 * changed Pure/Sequence interface (see Pure/seq.ML);
  5949 
  5950 
  5951 *** General Changes ***
  5952 
  5953 * hierachically structured name spaces (for consts, types, axms, thms
  5954 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  5955 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  5956 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  5957 long_names for fully qualified output names; NOTE: ML programs
  5958 (special tactics, packages etc.) referring to internal names may have
  5959 to be adapted to cope with fully qualified names; in case of severe
  5960 backward campatibility problems try setting 'global_names' at compile
  5961 time to have enrything declared within a flat name space; one may also
  5962 fine tune name declarations in theories via the 'global' and 'local'
  5963 section;
  5964 
  5965 * reimplemented the implicit simpset and claset using the new anytype
  5966 data filed in signatures; references simpset:simpset ref etc. are
  5967 replaced by functions simpset:unit->simpset and
  5968 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  5969 to patch your ML files accordingly;
  5970 
  5971 * HTML output now includes theory graph data for display with Java
  5972 applet or isatool browser; data generated automatically via isatool
  5973 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  5974 
  5975 * defs may now be conditional; improved rewrite_goals_tac to handle
  5976 conditional equations;
  5977 
  5978 * defs now admits additional type arguments, using TYPE('a) syntax;
  5979 
  5980 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  5981 creates a new theory node; implicit merge of thms' signatures is
  5982 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  5983 transfer:theory->thm->thm in (rare) cases;
  5984 
  5985 * improved handling of draft signatures / theories; draft thms (and
  5986 ctyps, cterms) are automatically promoted to real ones;
  5987 
  5988 * slightly changed interfaces for oracles: admit many per theory, named
  5989 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  5990 
  5991 * print_goals: optional output of const types (set show_consts and
  5992 show_types);
  5993 
  5994 * improved output of warnings (###) and errors (***);
  5995 
  5996 * subgoal_tac displays a warning if the new subgoal has type variables;
  5997 
  5998 * removed old README and Makefiles;
  5999 
  6000 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  6001 
  6002 * removed obsolete init_pps and init_database;
  6003 
  6004 * deleted the obsolete tactical STATE, which was declared by
  6005     fun STATE tacfun st = tacfun st st;
  6006 
  6007 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  6008 (which abbreviates $HOME);
  6009 
  6010 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  6011 use isatool fixseq to adapt your ML programs (this works for fully
  6012 qualified references to the Sequence structure only!);
  6013 
  6014 * use_thy no longer requires writable current directory; it always
  6015 reloads .ML *and* .thy file, if either one is out of date;
  6016 
  6017 
  6018 *** Classical Reasoner ***
  6019 
  6020 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  6021 tactics that use classical reasoning to simplify a subgoal without
  6022 splitting it into several subgoals;
  6023 
  6024 * Safe_tac: like safe_tac but uses the default claset;
  6025 
  6026 
  6027 *** Simplifier ***
  6028 
  6029 * added simplification meta rules:
  6030     (asm_)(full_)simplify: simpset -> thm -> thm;
  6031 
  6032 * simplifier.ML no longer part of Pure -- has to be loaded by object
  6033 logics (again);
  6034 
  6035 * added prems argument to simplification procedures;
  6036 
  6037 * HOL, FOL, ZF: added infix function `addsplits':
  6038   instead of `<simpset> setloop (split_tac <thms>)'
  6039   you can simply write `<simpset> addsplits <thms>'
  6040 
  6041 
  6042 *** Syntax ***
  6043 
  6044 * TYPE('a) syntax for type reflection terms;
  6045 
  6046 * no longer handles consts with name "" -- declare as 'syntax' instead;
  6047 
  6048 * pretty printer: changed order of mixfix annotation preference (again!);
  6049 
  6050 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  6051 
  6052 
  6053 *** HOL ***
  6054 
  6055 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  6056   with `addloop' of the simplifier to faciliate case splitting in premises.
  6057 
  6058 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  6059 
  6060 * HOL/Auth: new protocol proofs including some for the Internet
  6061   protocol TLS;
  6062 
  6063 * HOL/Map: new theory of `maps' a la VDM;
  6064 
  6065 * HOL/simplifier: simplification procedures nat_cancel_sums for
  6066 cancelling out common nat summands from =, <, <= (in)equalities, or
  6067 differences; simplification procedures nat_cancel_factor for
  6068 cancelling common factor from =, <, <= (in)equalities over natural
  6069 sums; nat_cancel contains both kinds of procedures, it is installed by
  6070 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  6071 
  6072 * HOL/simplifier: terms of the form
  6073   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  6074   are rewritten to
  6075   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  6076   and those of the form
  6077   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  6078   are rewritten to
  6079   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  6080 
  6081 * HOL/datatype
  6082   Each datatype `t' now comes with a theorem `split_t_case' of the form
  6083 
  6084   P(t_case f1 ... fn x) =
  6085      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  6086         ...
  6087        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  6088      )
  6089 
  6090   and a theorem `split_t_case_asm' of the form
  6091 
  6092   P(t_case f1 ... fn x) =
  6093     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  6094         ...
  6095        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  6096      )
  6097   which can be added to a simpset via `addsplits'. The existing theorems
  6098   expand_list_case and expand_option_case have been renamed to
  6099   split_list_case and split_option_case.
  6100 
  6101 * HOL/Arithmetic:
  6102   - `pred n' is automatically converted to `n-1'.
  6103     Users are strongly encouraged not to use `pred' any longer,
  6104     because it will disappear altogether at some point.
  6105   - Users are strongly encouraged to write "0 < n" rather than
  6106     "n ~= 0". Theorems and proof tools have been modified towards this
  6107     `standard'.
  6108 
  6109 * HOL/Lists:
  6110   the function "set_of_list" has been renamed "set" (and its theorems too);
  6111   the function "nth" now takes its arguments in the reverse order and
  6112   has acquired the infix notation "!" as in "xs!n".
  6113 
  6114 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  6115 
  6116 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  6117   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  6118 
  6119 * HOL/record: extensible records with schematic structural subtyping
  6120 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  6121 still lacks various theorems and concrete record syntax;
  6122 
  6123 
  6124 *** HOLCF ***
  6125 
  6126 * removed "axioms" and "generated by" sections;
  6127 
  6128 * replaced "ops" section by extended "consts" section, which is capable of
  6129   handling the continuous function space "->" directly;
  6130 
  6131 * domain package:
  6132   . proves theorems immediately and stores them in the theory,
  6133   . creates hierachical name space,
  6134   . now uses normal mixfix annotations (instead of cinfix...),
  6135   . minor changes to some names and values (for consistency),
  6136   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  6137   . separator between mutual domain defs: changed "," to "and",
  6138   . improved handling of sort constraints;  now they have to
  6139     appear on the left-hand side of the equations only;
  6140 
  6141 * fixed LAM <x,y,zs>.b syntax;
  6142 
  6143 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  6144 adm (%x. P (t x)), where P is chainfinite and t continuous;
  6145 
  6146 
  6147 *** FOL and ZF ***
  6148 
  6149 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  6150   with `addloop' of the simplifier to faciliate case splitting in premises.
  6151 
  6152 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  6153 in HOL, they strip ALL and --> from proved theorems;
  6154 
  6155 
  6156 
  6157 New in Isabelle94-8 (May 1997)
  6158 ------------------------------
  6159 
  6160 *** General Changes ***
  6161 
  6162 * new utilities to build / run / maintain Isabelle etc. (in parts
  6163 still somewhat experimental); old Makefiles etc. still functional;
  6164 
  6165 * new 'Isabelle System Manual';
  6166 
  6167 * INSTALL text, together with ./configure and ./build scripts;
  6168 
  6169 * reimplemented type inference for greater efficiency, better error
  6170 messages and clean internal interface;
  6171 
  6172 * prlim command for dealing with lots of subgoals (an easier way of
  6173 setting goals_limit);
  6174 
  6175 
  6176 *** Syntax ***
  6177 
  6178 * supports alternative (named) syntax tables (parser and pretty
  6179 printer); internal interface is provided by add_modesyntax(_i);
  6180 
  6181 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  6182 be used in conjunction with the Isabelle symbol font; uses the
  6183 "symbols" syntax table;
  6184 
  6185 * added token_translation interface (may translate name tokens in
  6186 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  6187 the current print_mode); IMPORTANT: user print translation functions
  6188 are responsible for marking newly introduced bounds
  6189 (Syntax.mark_boundT);
  6190 
  6191 * token translations for modes "xterm" and "xterm_color" that display
  6192 names in bold, underline etc. or colors (which requires a color
  6193 version of xterm);
  6194 
  6195 * infixes may now be declared with names independent of their syntax;
  6196 
  6197 * added typed_print_translation (like print_translation, but may
  6198 access type of constant);
  6199 
  6200 
  6201 *** Classical Reasoner ***
  6202 
  6203 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  6204 some limitations.  Blast_tac...
  6205   + ignores addss, addbefore, addafter; this restriction is intrinsic
  6206   + ignores elimination rules that don't have the correct format
  6207         (the conclusion MUST be a formula variable)
  6208   + ignores types, which can make HOL proofs fail
  6209   + rules must not require higher-order unification, e.g. apply_type in ZF
  6210     [message "Function Var's argument not a bound variable" relates to this]
  6211   + its proof strategy is more general but can actually be slower
  6212 
  6213 * substitution with equality assumptions no longer permutes other
  6214 assumptions;
  6215 
  6216 * minor changes in semantics of addafter (now called addaltern); renamed
  6217 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  6218 (and access functions for it);
  6219 
  6220 * improved combination of classical reasoner and simplifier:
  6221   + functions for handling clasimpsets
  6222   + improvement of addss: now the simplifier is called _after_ the
  6223     safe steps.
  6224   + safe variant of addss called addSss: uses safe simplifications
  6225     _during_ the safe steps. It is more complete as it allows multiple
  6226     instantiations of unknowns (e.g. with slow_tac).
  6227 
  6228 *** Simplifier ***
  6229 
  6230 * added interface for simplification procedures (functions that
  6231 produce *proven* rewrite rules on the fly, depending on current
  6232 redex);
  6233 
  6234 * ordering on terms as parameter (used for ordered rewriting);
  6235 
  6236 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  6237 
  6238 * the solver is now split into a safe and an unsafe part.
  6239 This should be invisible for the normal user, except that the
  6240 functions setsolver and addsolver have been renamed to setSolver and
  6241 addSolver; added safe_asm_full_simp_tac;
  6242 
  6243 
  6244 *** HOL ***
  6245 
  6246 * a generic induction tactic `induct_tac' which works for all datatypes and
  6247 also for type `nat';
  6248 
  6249 * a generic case distinction tactic `exhaust_tac' which works for all
  6250 datatypes and also for type `nat';
  6251 
  6252 * each datatype comes with a function `size';
  6253 
  6254 * patterns in case expressions allow tuple patterns as arguments to
  6255 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  6256 
  6257 * primrec now also works with type n