NEWS
author wenzelm
Thu, 22 Sep 2011 21:58:05 +0200
changeset 45922 9cf265a192f6
parent 45887 a5d43ffc95eb
child 45906 0523a6be8ade
permissions -rw-r--r--
made SML/NJ happy;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in Isabelle2011-1 (October 2011)
     5 ------------------------------------
     6 
     7 *** General ***
     8 
     9 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
    10 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
    11 
    12   - Management of multiple theory files directly from the editor
    13     buffer store -- bypassing the file-system (no requirement to save
    14     files for checking).
    15 
    16   - Markup of formal entities within the text buffer, with semantic
    17     highlighting, tooltips and hyperlinks to jump to defining source
    18     positions.
    19 
    20   - Improved text rendering, with sub/superscripts in the source
    21     buffer (including support for copy/paste wrt. output panel, HTML
    22     theory output and other non-Isabelle text boxes).
    23 
    24   - Refined scheduling of proof checking and printing of results,
    25     based on interactive editor view.  (Note: jEdit folding and
    26     narrowing allows to restrict buffer perspectives explicitly.)
    27 
    28   - Reduced CPU performance requirements, usable on machines with few
    29     cores.
    30 
    31   - Reduced memory requirements due to pruning of unused document
    32     versions (garbage collection).
    33 
    34 See also ~~/src/Tools/jEdit/README.html for further information,
    35 including some remaining limitations.
    36 
    37 * Theory loader: source files are exclusively located via the master
    38 directory of each theory node (where the .thy file itself resides).
    39 The global load path (such as src/HOL/Library) has been discontinued.
    40 Note that the path element ~~ may be used to reference theories in the
    41 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    42 INCOMPATIBILITY.
    43 
    44 * Theory loader: source files are identified by content via SHA1
    45 digests.  Discontinued former path/modtime identification and optional
    46 ISABELLE_FILE_IDENT plugin scripts.
    47 
    48 * Parallelization of nested Isar proofs is subject to
    49 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    50 usedir option -Q.
    51 
    52 * Name space: former unsynchronized references are now proper
    53 configuration options, with more conventional names:
    54 
    55   long_names   ~> names_long
    56   short_names  ~> names_short
    57   unique_names ~> names_unique
    58 
    59 Minor INCOMPATIBILITY, need to declare options in context like this:
    60 
    61   declare [[names_unique = false]]
    62 
    63 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    64 that the result needs to be unique, which means fact specifications
    65 may have to be refined after enriching a proof context.
    66 
    67 * Attribute "case_names" has been refined: the assumptions in each case
    68 can be named now by following the case name with [name1 name2 ...].
    69 
    70 * Isabelle/Isar reference manual has been updated and extended:
    71   - "Synopsis" provides a catalog of main Isar language concepts.
    72   - Formal references in syntax diagrams, via @{rail} antiquotation.
    73   - Updated material from classic "ref" manual, notably about
    74     "Classical Reasoner".
    75 
    76 
    77 *** HOL ***
    78 
    79 * New proof method "induction" that gives induction hypotheses the name IH,
    80 thus distinguishing them from further hypotheses that come from rule
    81 induction.  The latter are still called "hyps".  Method "induction" is a thin
    82 wrapper around "induct" and follows the same syntax.
    83 
    84 * Class bot and top require underlying partial order rather than
    85 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    86 
    87 * Class complete_lattice: generalized a couple of lemmas from sets;
    88 generalized theorems INF_cong and SUP_cong.  New type classes for
    89 complete boolean algebras and complete linear orders.  Lemmas
    90 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
    91 class complete_linorder.
    92 
    93 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
    94 Sup_fun_def, Inf_apply, Sup_apply.
    95 
    96 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
    97 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
    98 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union, INF_subset,
    99 UNION_eq_Union_image, Union_def, UN_eq have been discarded.
   100 
   101 More consistent and comprehensive names:
   102 
   103   INFI_def ~> INF_def
   104   SUPR_def ~> SUP_def
   105   INF_leI ~> INF_lower
   106   INF_leI2 ~> INF_lower2
   107   le_INFI ~> INF_greatest
   108   le_SUPI ~> SUP_upper
   109   le_SUPI2 ~> SUP_upper2
   110   SUP_leI ~> SUP_least
   111   INFI_bool_eq ~> INF_bool_eq
   112   SUPR_bool_eq ~> SUP_bool_eq
   113   INFI_apply ~> INF_apply
   114   SUPR_apply ~> SUP_apply
   115   INTER_def ~> INTER_eq
   116   UNION_def ~> UNION_eq
   117 
   118 INCOMPATIBILITY.
   119 
   120 * Renamed theory Complete_Lattice to Complete_Lattices.
   121 INCOMPATIBILITY.
   122 
   123 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   124 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   125 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   126 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   127 
   128 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   129 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   130 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   131 INCOMPATIBILITY.
   132 
   133 * Added syntactic classes "inf" and "sup" for the respective
   134 constants.  INCOMPATIBILITY: Changes in the argument order of the
   135 (mostly internal) locale predicates for some derived classes.
   136 
   137 * Theorem collections ball_simps and bex_simps do not contain theorems
   138 referring to UNION any longer; these have been moved to collection
   139 UN_ball_bex_simps.  INCOMPATIBILITY.
   140 
   141 * Theory Archimedean_Field: floor now is defined as parameter of a
   142 separate type class floor_ceiling.
   143 
   144 * Theory Finite_Set: more coherent development of fold_set locales:
   145 
   146     locale fun_left_comm ~> locale comp_fun_commute
   147     locale fun_left_comm_idem ~> locale comp_fun_idem
   148 
   149 Both use point-free characterization; interpretation proofs may need
   150 adjustment.  INCOMPATIBILITY.
   151 
   152 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   153 accordance with standard mathematical terminology. INCOMPATIBILITY.
   154 
   155 * Theory Complex_Main: The locale interpretations for the
   156 bounded_linear and bounded_bilinear locales have been removed, in
   157 order to reduce the number of duplicate lemmas. Users must use the
   158 original names for distributivity theorems, potential INCOMPATIBILITY.
   159 
   160   divide.add ~> add_divide_distrib
   161   divide.diff ~> diff_divide_distrib
   162   divide.setsum ~> setsum_divide_distrib
   163   mult.add_right ~> right_distrib
   164   mult.diff_right ~> right_diff_distrib
   165   mult_right.setsum ~> setsum_right_distrib
   166   mult_left.diff ~> left_diff_distrib
   167 
   168 * Theory Complex_Main: Several redundant theorems have been removed or
   169 replaced by more general versions. INCOMPATIBILITY.
   170 
   171   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   172   real_0_le_divide_iff ~> zero_le_divide_iff
   173   realpow_two_disj ~> power2_eq_iff
   174   real_squared_diff_one_factored ~> square_diff_one_factored
   175   realpow_two_diff ~> square_diff_square_factored
   176   reals_complete2 ~> complete_real
   177   real_sum_squared_expand ~> power2_sum
   178   exp_ln_eq ~> ln_unique
   179   expi_add ~> exp_add
   180   expi_zero ~> exp_zero
   181   lemma_DERIV_subst ~> DERIV_cong
   182   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   183   LIMSEQ_const ~> tendsto_const
   184   LIMSEQ_norm ~> tendsto_norm
   185   LIMSEQ_add ~> tendsto_add
   186   LIMSEQ_minus ~> tendsto_minus
   187   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   188   LIMSEQ_diff ~> tendsto_diff
   189   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   190   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   191   LIMSEQ_mult ~> tendsto_mult
   192   LIMSEQ_inverse ~> tendsto_inverse
   193   LIMSEQ_divide ~> tendsto_divide
   194   LIMSEQ_pow ~> tendsto_power
   195   LIMSEQ_setsum ~> tendsto_setsum
   196   LIMSEQ_setprod ~> tendsto_setprod
   197   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   198   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   199   LIMSEQ_imp_rabs ~> tendsto_rabs
   200   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   201   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   202   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   203   LIMSEQ_Complex ~> tendsto_Complex
   204   LIM_ident ~> tendsto_ident_at
   205   LIM_const ~> tendsto_const
   206   LIM_add ~> tendsto_add
   207   LIM_add_zero ~> tendsto_add_zero
   208   LIM_minus ~> tendsto_minus
   209   LIM_diff ~> tendsto_diff
   210   LIM_norm ~> tendsto_norm
   211   LIM_norm_zero ~> tendsto_norm_zero
   212   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   213   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   214   LIM_rabs ~> tendsto_rabs
   215   LIM_rabs_zero ~> tendsto_rabs_zero
   216   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   217   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   218   LIM_compose ~> tendsto_compose
   219   LIM_mult ~> tendsto_mult
   220   LIM_scaleR ~> tendsto_scaleR
   221   LIM_of_real ~> tendsto_of_real
   222   LIM_power ~> tendsto_power
   223   LIM_inverse ~> tendsto_inverse
   224   LIM_sgn ~> tendsto_sgn
   225   isCont_LIM_compose ~> isCont_tendsto_compose
   226   bounded_linear.LIM ~> bounded_linear.tendsto
   227   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   228   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   229   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   230   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   231   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   232   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   233 
   234 * Theory Complex_Main: The definition of infinite series was
   235 generalized.  Now it is defined on the type class {topological_space,
   236 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   237 
   238 * Theory Complex_Main: The complex exponential function "expi" is now
   239 a type-constrained abbreviation for "exp :: complex => complex"; thus
   240 several polymorphic lemmas about "exp" are now applicable to "expi".
   241 
   242 * Code generation:
   243 
   244   - Theory Library/Code_Char_ord provides native ordering of
   245     characters in the target language.
   246 
   247   - Commands code_module and code_library are legacy, use export_code
   248     instead.
   249 
   250   - Method "evaluation" is legacy, use method "eval" instead.
   251 
   252   - Legacy evaluator "SML" is deactivated by default.  May be
   253     reactivated by the following theory command:
   254 
   255       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   256 
   257 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   258 
   259 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   260 still available as a legacy feature for some time.
   261 
   262 * Nitpick:
   263   - Added "need" and "total_consts" options.
   264   - Reintroduced "show_skolems" option by popular demand.
   265   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   266     INCOMPATIBILITY.
   267 
   268 * Sledgehammer:
   269   - Use quasi-sound (and efficient) translations by default.
   270   - Added support for the following provers: E-ToFoF, LEO-II,
   271     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   272   - Automatically preplay and minimize proofs before showing them if
   273     this can be done within reasonable time.
   274   - sledgehammer available_provers ~> sledgehammer supported_provers.
   275     INCOMPATIBILITY.
   276   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   277     "max_mono_iters", and "max_new_mono_instances" options.
   278   - Removed "explicit_apply" and "full_types" options as well as "Full
   279     Types" Proof General menu item. INCOMPATIBILITY.
   280 
   281 * Metis:
   282   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   283   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   284     INCOMPATIBILITY.
   285 
   286 * Command 'try':
   287   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   288     "elim:" options. INCOMPATIBILITY.
   289   - Introduced 'try' that not only runs 'try_methods' but also
   290     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   291 
   292 * Quickcheck:
   293   - Added "eval" option to evaluate terms for the found counterexample
   294     (currently only supported by the default (exhaustive) tester).
   295   - Added post-processing of terms to obtain readable counterexamples
   296     (currently only supported by the default (exhaustive) tester).
   297   - New counterexample generator quickcheck[narrowing] enables
   298     narrowing-based testing.  Requires the Glasgow Haskell compiler
   299     with its installation location defined in the Isabelle settings
   300     environment as ISABELLE_GHC.
   301   - Removed quickcheck tester "SML" based on the SML code generator
   302     (formly in HOL/Library).
   303 
   304 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   305 use 'partial_function' instead.
   306 
   307 * Theory Library/Extended_Reals replaces now the positive extended
   308 reals found in probability theory. This file is extended by
   309 Multivariate_Analysis/Extended_Real_Limits.
   310 
   311 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   312 from where it must be imported explicitly if it is really required.
   313 INCOMPATIBILITY.
   314 
   315 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   316 been moved here.  INCOMPATIBILITY.
   317 
   318 * Theory Library/Saturated provides type of numbers with saturated
   319 arithmetic.
   320 
   321 * Theory Library/Product_Lattice defines a pointwise ordering for the
   322 product type 'a * 'b, and provides instance proofs for various order
   323 and lattice type classes.
   324 
   325 * Theory Library/Countable now provides the "countable_datatype" proof
   326 method for proving "countable" class instances for datatypes.
   327 
   328 * Theory Library/Cset_Monad allows do notation for computable sets
   329 (cset) via the generic monad ad-hoc overloading facility.
   330 
   331 * Library: Theories of common data structures are split into theories
   332 for implementation, an invariant-ensuring type, and connection to an
   333 abstract type. INCOMPATIBILITY.
   334 
   335   - RBT is split into RBT and RBT_Mapping.
   336   - AssocList is split and renamed into AList and AList_Mapping.
   337   - DList is split into DList_Impl, DList, and DList_Cset.
   338   - Cset is split into Cset and List_Cset.
   339 
   340 * Theory Library/Nat_Infinity has been renamed to
   341 Library/Extended_Nat, with name changes of the following types and
   342 constants:
   343 
   344   type inat   ~> type enat
   345   Fin         ~> enat
   346   Infty       ~> infinity (overloaded)
   347   iSuc        ~> eSuc
   348   the_Fin     ~> the_enat
   349 
   350 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   351 been renamed accordingly. INCOMPATIBILITY.
   352 
   353 * Session Multivariate_Analysis: The euclidean_space type class now
   354 fixes a constant "Basis :: 'a set" consisting of the standard
   355 orthonormal basis for the type. Users now have the option of
   356 quantifying over this set instead of using the "basis" function, e.g.
   357 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   358 
   359 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   360 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   361 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   362 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   363 changed to match. Definition theorems for overloaded constants now use
   364 the standard "foo_vec_def" naming scheme. A few other theorems have
   365 been renamed as follows (INCOMPATIBILITY):
   366 
   367   Cart_eq          ~> vec_eq_iff
   368   dist_nth_le_cart ~> dist_vec_nth_le
   369   tendsto_vector   ~> vec_tendstoI
   370   Cauchy_vector    ~> vec_CauchyI
   371 
   372 * Session Multivariate_Analysis: Several duplicate theorems have been
   373 removed, and other theorems have been renamed or replaced with more
   374 general versions. INCOMPATIBILITY.
   375 
   376   finite_choice ~> finite_set_choice
   377   eventually_conjI ~> eventually_conj
   378   eventually_and ~> eventually_conj_iff
   379   eventually_false ~> eventually_False
   380   setsum_norm ~> norm_setsum
   381   Lim_sequentially ~> LIMSEQ_def
   382   Lim_ident_at ~> LIM_ident
   383   Lim_const ~> tendsto_const
   384   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   385   Lim_neg ~> tendsto_minus
   386   Lim_add ~> tendsto_add
   387   Lim_sub ~> tendsto_diff
   388   Lim_mul ~> tendsto_scaleR
   389   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   390   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   391   Lim_linear ~> bounded_linear.tendsto
   392   Lim_component ~> tendsto_euclidean_component
   393   Lim_component_cart ~> tendsto_vec_nth
   394   Lim_inner ~> tendsto_inner [OF tendsto_const]
   395   dot_lsum ~> inner_setsum_left
   396   dot_rsum ~> inner_setsum_right
   397   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   398   continuous_neg ~> continuous_minus
   399   continuous_sub ~> continuous_diff
   400   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   401   continuous_mul ~> continuous_scaleR
   402   continuous_inv ~> continuous_inverse
   403   continuous_at_within_inv ~> continuous_at_within_inverse
   404   continuous_at_inv ~> continuous_at_inverse
   405   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   406   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   407   continuous_at_component ~> continuous_component [OF continuous_at_id]
   408   continuous_on_neg ~> continuous_on_minus
   409   continuous_on_sub ~> continuous_on_diff
   410   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   411   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   412   continuous_on_mul ~> continuous_on_scaleR
   413   continuous_on_mul_real ~> continuous_on_mult
   414   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   415   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   416   continuous_on_inverse ~> continuous_on_inv
   417   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   418   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   419   subset_interior ~> interior_mono
   420   subset_closure ~> closure_mono
   421   closure_univ ~> closure_UNIV
   422   real_arch_lt ~> reals_Archimedean2
   423   real_arch ~> reals_Archimedean3
   424   real_abs_norm ~> abs_norm_cancel
   425   real_abs_sub_norm ~> norm_triangle_ineq3
   426   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   427 
   428 * Session HOL-Probability:
   429   - Caratheodory's extension lemma is now proved for ring_of_sets.
   430   - Infinite products of probability measures are now available.
   431   - Sigma closure is independent, if the generator is independent
   432   - Use extended reals instead of positive extended
   433     reals. INCOMPATIBILITY.
   434 
   435 
   436 *** Document preparation ***
   437 
   438 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   439 isar-ref manual, both for description and actual application of the
   440 same.
   441 
   442 * Antiquotation @{value} evaluates the given term and presents its
   443 result.
   444 
   445 * Antiquotations: term style "isub" provides ad-hoc conversion of
   446 variables x1, y23 into subscripted form x\<^isub>1,
   447 y\<^isub>2\<^isub>3.
   448 
   449 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   450 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   451 
   452 * Localized \isabellestyle switch can be used within blocks or groups
   453 like this:
   454 
   455   \isabellestyle{it}  %preferred default
   456   {\isabellestylett @{text "typewriter stuff"}}
   457 
   458 * Discontinued special treatment of hard tabulators.  Implicit
   459 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   460 layouts.
   461 
   462 
   463 *** ML ***
   464 
   465 * The inner syntax of sort/type/term/prop supports inlined YXML
   466 representations within quoted string tokens.  By encoding logical
   467 entities via Term_XML (in ML or Scala) concrete syntax can be
   468 bypassed, which is particularly useful for producing bits of text
   469 under external program control.
   470 
   471 * Antiquotations for ML and document preparation are managed as theory
   472 data, which requires explicit setup.
   473 
   474 * Isabelle_Process.is_active allows tools to check if the official
   475 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   476 (better known as Proof General).
   477 
   478 * Structure Proof_Context follows standard naming scheme.  Old
   479 ProofContext is still available for some time as legacy alias.
   480 
   481 * Structure Timing provides various operations for timing; supersedes
   482 former start_timing/end_timing etc.
   483 
   484 * Path.print is the official way to show file-system paths to users
   485 (including quotes etc.).
   486 
   487 * Inner syntax: identifiers in parse trees of generic categories
   488 "logic", "aprop", "idt" etc. carry position information (disguised as
   489 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   490 translations that choke on unexpected type constraints.  Positions can
   491 be stripped in ML translations via Syntax.strip_positions /
   492 Syntax.strip_positions_ast, or via the syntax constant
   493 "_strip_positions" within parse trees.  As last resort, positions can
   494 be disabled via the configuration option Syntax.positions, which is
   495 called "syntax_positions" in Isar attribute syntax.
   496 
   497 * Discontinued special status of various ML structures that contribute
   498 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   499 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   500 refer directly to Ast.Constant, Lexicon.is_identifier,
   501 Syntax_Trans.mk_binder_tr etc.
   502 
   503 * Typed print translation: discontinued show_sorts argument, which is
   504 already available via context of "advanced" translation.
   505 
   506 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   507 goal states; body tactic needs to address all subgoals uniformly.
   508 
   509 * Slightly more special eq_list/eq_set, with shortcut involving
   510 pointer equality (assumes that eq relation is reflexive).
   511 
   512 * Classical tactics use proper Proof.context instead of historic types
   513 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   514 operate directly on Proof.context.  Raw type claset retains its use as
   515 snapshot of the classical context, which can be recovered via
   516 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   517 INCOMPATIBILITY, classical tactics and derived proof methods require
   518 proper Proof.context.
   519 
   520 
   521 *** System ***
   522 
   523 * Discontinued support for Poly/ML 5.2, which was the last version
   524 without proper multithreading and TimeLimit implementation.
   525 
   526 * Discontinued old lib/scripts/polyml-platform, which has been
   527 obsolete since Isabelle2009-2.
   528 
   529 * Various optional external tools are referenced more robustly and
   530 uniformly by explicit Isabelle settings as follows:
   531 
   532   ISABELLE_CSDP   (formerly CSDP_EXE)
   533   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
   534   ISABELLE_OCAML  (formerly EXEC_OCAML)
   535   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
   536   ISABELLE_YAP    (formerly EXEC_YAP)
   537 
   538 Note that automated detection from the file-system or search path has
   539 been discontinued.  INCOMPATIBILITY.
   540 
   541 * Scala layer provides JVM method invocation service for static
   542 methods of type (String)String, see Invoke_Scala.method in ML.  For
   543 example:
   544 
   545   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   546 
   547 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
   548 this allows to pass structured values between ML and Scala.
   549 
   550 * The IsabelleText fonts includes some further glyphs to support the
   551 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
   552 installed a local copy (which is normally *not* required) need to
   553 delete or update it from ~~/lib/fonts/.
   554 
   555 
   556 New in Isabelle2011 (January 2011)
   557 ----------------------------------
   558 
   559 *** General ***
   560 
   561 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   562 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   563 useful tooltips and hyperlinks produced from its static analysis.  The
   564 bundled component provides an executable Isabelle tool that can be run
   565 like this:
   566 
   567   Isabelle2011/bin/isabelle jedit
   568 
   569 * Significantly improved Isabelle/Isar implementation manual.
   570 
   571 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   572 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   573 while the default heap location within that directory lacks that extra
   574 suffix.  This isolates multiple Isabelle installations from each
   575 other, avoiding problems with old settings in new versions.
   576 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   577 
   578 * Source files are always encoded as UTF-8, instead of old-fashioned
   579 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   580 the following package declarations:
   581 
   582   \usepackage[utf8]{inputenc}
   583   \usepackage{textcomp}
   584 
   585 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   586 a Unicode character is treated as a single symbol, not a sequence of
   587 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   588 contain symbols without further backslash escapes, Unicode can now be
   589 used here as well.  Recall that Symbol.explode in ML provides a
   590 consistent view on symbols, while raw explode (or String.explode)
   591 merely give a byte-oriented representation.
   592 
   593 * Theory loader: source files are primarily located via the master
   594 directory of each theory node (where the .thy file itself resides).
   595 The global load path is still partially available as legacy feature.
   596 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   597 explicit paths, relatively to the theory.
   598 
   599 * Special treatment of ML file names has been discontinued.
   600 Historically, optional extensions .ML or .sml were added on demand --
   601 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   602 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   603 
   604 * Various options that affect pretty printing etc. are now properly
   605 handled within the context via configuration options, instead of
   606 unsynchronized references or print modes.  There are both ML Config.T
   607 entities and Isar declaration attributes to access these.
   608 
   609   ML (Config.T)                 Isar (attribute)
   610 
   611   eta_contract                  eta_contract
   612   show_brackets                 show_brackets
   613   show_sorts                    show_sorts
   614   show_types                    show_types
   615   show_question_marks           show_question_marks
   616   show_consts                   show_consts
   617   show_abbrevs                  show_abbrevs
   618 
   619   Syntax.ast_trace              syntax_ast_trace
   620   Syntax.ast_stat               syntax_ast_stat
   621   Syntax.ambiguity_level        syntax_ambiguity_level
   622 
   623   Goal_Display.goals_limit      goals_limit
   624   Goal_Display.show_main_goal   show_main_goal
   625 
   626   Method.rule_trace             rule_trace
   627 
   628   Thy_Output.display            thy_output_display
   629   Thy_Output.quotes             thy_output_quotes
   630   Thy_Output.indent             thy_output_indent
   631   Thy_Output.source             thy_output_source
   632   Thy_Output.break              thy_output_break
   633 
   634 Note that corresponding "..._default" references in ML may only be
   635 changed globally at the ROOT session setup, but *not* within a theory.
   636 The option "show_abbrevs" supersedes the former print mode
   637 "no_abbrevs" with inverted meaning.
   638 
   639 * More systematic naming of some configuration options.
   640 INCOMPATIBILITY.
   641 
   642   trace_simp  ~>  simp_trace
   643   debug_simp  ~>  simp_debug
   644 
   645 * Support for real valued configuration options, using simplistic
   646 floating-point notation that coincides with the inner syntax for
   647 float_token.
   648 
   649 * Support for real valued preferences (with approximative PGIP type):
   650 front-ends need to accept "pgint" values in float notation.
   651 INCOMPATIBILITY.
   652 
   653 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   654 DejaVu Sans.
   655 
   656 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   657 
   658 
   659 *** Pure ***
   660 
   661 * Command 'type_synonym' (with single argument) replaces somewhat
   662 outdated 'types', which is still available as legacy feature for some
   663 time.
   664 
   665 * Command 'nonterminal' (with 'and' separated list of arguments)
   666 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   667 
   668 * Command 'notepad' replaces former 'example_proof' for
   669 experimentation in Isar without any result.  INCOMPATIBILITY.
   670 
   671 * Locale interpretation commands 'interpret' and 'sublocale' accept
   672 lists of equations to map definitions in a locale to appropriate
   673 entities in the context of the interpretation.  The 'interpretation'
   674 command already provided this functionality.
   675 
   676 * Diagnostic command 'print_dependencies' prints the locale instances
   677 that would be activated if the specified expression was interpreted in
   678 the current context.  Variant "print_dependencies!" assumes a context
   679 without interpretations.
   680 
   681 * Diagnostic command 'print_interps' prints interpretations in proofs
   682 in addition to interpretations in theories.
   683 
   684 * Discontinued obsolete 'global' and 'local' commands to manipulate
   685 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   686 Sign.root_path and Sign.local_path may be applied directly where this
   687 feature is still required for historical reasons.
   688 
   689 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   690 'definition' instead.
   691 
   692 * The "prems" fact, which refers to the accidental collection of
   693 foundational premises in the context, is now explicitly marked as
   694 legacy feature and will be discontinued soon.  Consider using "assms"
   695 of the head statement or reference facts by explicit names.
   696 
   697 * Document antiquotations @{class} and @{type} print classes and type
   698 constructors.
   699 
   700 * Document antiquotation @{file} checks file/directory entries within
   701 the local file system.
   702 
   703 
   704 *** HOL ***
   705 
   706 * Coercive subtyping: functions can be declared as coercions and type
   707 inference will add them as necessary upon input of a term.  Theory
   708 Complex_Main declares real :: nat => real and real :: int => real as
   709 coercions. A coercion function f is declared like this:
   710 
   711   declare [[coercion f]]
   712 
   713 To lift coercions through type constructors (e.g. from nat => real to
   714 nat list => real list), map functions can be declared, e.g.
   715 
   716   declare [[coercion_map map]]
   717 
   718 Currently coercion inference is activated only in theories including
   719 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   720 the configuration option "coercion_enabled", e.g. it can be enabled in
   721 other theories like this:
   722 
   723   declare [[coercion_enabled]]
   724 
   725 * Command 'partial_function' provides basic support for recursive
   726 function definitions over complete partial orders.  Concrete instances
   727 are provided for i) the option type, ii) tail recursion on arbitrary
   728 types, and iii) the heap monad of Imperative_HOL.  See
   729 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   730 for examples.
   731 
   732 * Function package: f.psimps rules are no longer implicitly declared
   733 as [simp].  INCOMPATIBILITY.
   734 
   735 * Datatype package: theorems generated for executable equality (class
   736 "eq") carry proper names and are treated as default code equations.
   737 
   738 * Inductive package: now offers command 'inductive_simps' to
   739 automatically derive instantiated and simplified equations for
   740 inductive predicates, similar to 'inductive_cases'.
   741 
   742 * Command 'enriched_type' allows to register properties of the
   743 functorial structure of types.
   744 
   745 * Improved infrastructure for term evaluation using code generator
   746 techniques, in particular static evaluation conversions.
   747 
   748 * Code generator: Scala (2.8 or higher) has been added to the target
   749 languages.
   750 
   751 * Code generator: globbing constant expressions "*" and "Theory.*"
   752 have been replaced by the more idiomatic "_" and "Theory._".
   753 INCOMPATIBILITY.
   754 
   755 * Code generator: export_code without explicit file declaration prints
   756 to standard output.  INCOMPATIBILITY.
   757 
   758 * Code generator: do not print function definitions for case
   759 combinators any longer.
   760 
   761 * Code generator: simplification with rules determined with
   762 src/Tools/Code/code_simp.ML and method "code_simp".
   763 
   764 * Code generator for records: more idiomatic representation of record
   765 types.  Warning: records are not covered by ancient SML code
   766 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   767 rep_datatype declaration helps to succeed then:
   768 
   769   record 'a foo = ...
   770   ...
   771   rep_datatype foo_ext ...
   772 
   773 * Records: logical foundation type for records does not carry a
   774 '_type' suffix any longer (obsolete due to authentic syntax).
   775 INCOMPATIBILITY.
   776 
   777 * Quickcheck now by default uses exhaustive testing instead of random
   778 testing.  Random testing can be invoked by "quickcheck [random]",
   779 exhaustive testing by "quickcheck [exhaustive]".
   780 
   781 * Quickcheck instantiates polymorphic types with small finite
   782 datatypes by default. This enables a simple execution mechanism to
   783 handle quantifiers and function equality over the finite datatypes.
   784 
   785 * Quickcheck random generator has been renamed from "code" to
   786 "random".  INCOMPATIBILITY.
   787 
   788 * Quickcheck now has a configurable time limit which is set to 30
   789 seconds by default. This can be changed by adding [timeout = n] to the
   790 quickcheck command. The time limit for Auto Quickcheck is still set
   791 independently.
   792 
   793 * Quickcheck in locales considers interpretations of that locale for
   794 counter example search.
   795 
   796 * Sledgehammer:
   797   - Added "smt" and "remote_smt" provers based on the "smt" proof
   798     method. See the Sledgehammer manual for details ("isabelle doc
   799     sledgehammer").
   800   - Renamed commands:
   801     sledgehammer atp_info ~> sledgehammer running_provers
   802     sledgehammer atp_kill ~> sledgehammer kill_provers
   803     sledgehammer available_atps ~> sledgehammer available_provers
   804     INCOMPATIBILITY.
   805   - Renamed options:
   806     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   807     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   808     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   809     (and "ms" and "min" are no longer supported)
   810     INCOMPATIBILITY.
   811 
   812 * Nitpick:
   813   - Renamed options:
   814     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   815     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   816     INCOMPATIBILITY.
   817   - Added support for partial quotient types.
   818   - Added local versions of the "Nitpick.register_xxx" functions.
   819   - Added "whack" option.
   820   - Allow registration of quotient types as codatatypes.
   821   - Improved "merge_type_vars" option to merge more types.
   822   - Removed unsound "fast_descrs" option.
   823   - Added custom symmetry breaking for datatypes, making it possible to reach
   824     higher cardinalities.
   825   - Prevent the expansion of too large definitions.
   826 
   827 * Proof methods "metis" and "meson" now have configuration options
   828 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   829 to diagnose these tools. E.g.
   830 
   831     using [[metis_trace = true]]
   832 
   833 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   834 manually as command 'solve_direct'.
   835 
   836 * The default SMT solver Z3 must be enabled explicitly (due to
   837 licensing issues) by setting the environment variable
   838 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   839 commercial applications, the SMT solver CVC3 is provided as fall-back;
   840 changing the SMT solver is done via the configuration option
   841 "smt_solver".
   842 
   843 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   844 i.e. "remote_cvc3" and "remote_z3".
   845 
   846 * Added basic SMT support for datatypes, records, and typedefs using
   847 the oracle mode (no proofs).  Direct support of pairs has been dropped
   848 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   849 support for a similar behavior).  Minor INCOMPATIBILITY.
   850 
   851 * Changed SMT configuration options:
   852   - Renamed:
   853     z3_proofs ~> smt_oracle (with inverted meaning)
   854     z3_trace_assms ~> smt_trace_used_facts
   855     INCOMPATIBILITY.
   856   - Added:
   857     smt_verbose
   858     smt_random_seed
   859     smt_datatypes
   860     smt_infer_triggers
   861     smt_monomorph_limit
   862     cvc3_options
   863     remote_cvc3_options
   864     remote_z3_options
   865     yices_options
   866 
   867 * Boogie output files (.b2i files) need to be declared in the theory
   868 header.
   869 
   870 * Simplification procedure "list_to_set_comprehension" rewrites list
   871 comprehensions applied to List.set to set comprehensions.  Occasional
   872 INCOMPATIBILITY, may be deactivated like this:
   873 
   874   declare [[simproc del: list_to_set_comprehension]]
   875 
   876 * Removed old version of primrec package.  INCOMPATIBILITY.
   877 
   878 * Removed simplifier congruence rule of "prod_case", as has for long
   879 been the case with "split".  INCOMPATIBILITY.
   880 
   881 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   882 
   883 * Removed [split_format ... and ... and ...] version of
   884 [split_format].  Potential INCOMPATIBILITY.
   885 
   886 * Predicate "sorted" now defined inductively, with nice induction
   887 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   888 
   889 * Constant "contents" renamed to "the_elem", to free the generic name
   890 contents for other uses.  INCOMPATIBILITY.
   891 
   892 * Renamed class eq and constant eq (for code generation) to class
   893 equal and constant equal, plus renaming of related facts and various
   894 tuning.  INCOMPATIBILITY.
   895 
   896 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   897 
   898 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   899 INCOMPATIBILITY.
   900 
   901 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   902 avoid confusion with finite sets.  INCOMPATIBILITY.
   903 
   904 * Abandoned locales equiv, congruent and congruent2 for equivalence
   905 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   906 for congruent(2)).
   907 
   908 * Some previously unqualified names have been qualified:
   909 
   910   types
   911     bool ~> HOL.bool
   912     nat ~> Nat.nat
   913 
   914   constants
   915     Trueprop ~> HOL.Trueprop
   916     True ~> HOL.True
   917     False ~> HOL.False
   918     op & ~> HOL.conj
   919     op | ~> HOL.disj
   920     op --> ~> HOL.implies
   921     op = ~> HOL.eq
   922     Not ~> HOL.Not
   923     The ~> HOL.The
   924     All ~> HOL.All
   925     Ex ~> HOL.Ex
   926     Ex1 ~> HOL.Ex1
   927     Let ~> HOL.Let
   928     If ~> HOL.If
   929     Ball ~> Set.Ball
   930     Bex ~> Set.Bex
   931     Suc ~> Nat.Suc
   932     Pair ~> Product_Type.Pair
   933     fst ~> Product_Type.fst
   934     snd ~> Product_Type.snd
   935     curry ~> Product_Type.curry
   936     op : ~> Set.member
   937     Collect ~> Set.Collect
   938 
   939 INCOMPATIBILITY.
   940 
   941 * More canonical naming convention for some fundamental definitions:
   942 
   943     bot_bool_eq ~> bot_bool_def
   944     top_bool_eq ~> top_bool_def
   945     inf_bool_eq ~> inf_bool_def
   946     sup_bool_eq ~> sup_bool_def
   947     bot_fun_eq  ~> bot_fun_def
   948     top_fun_eq  ~> top_fun_def
   949     inf_fun_eq  ~> inf_fun_def
   950     sup_fun_eq  ~> sup_fun_def
   951 
   952 INCOMPATIBILITY.
   953 
   954 * More stylized fact names:
   955 
   956   expand_fun_eq ~> fun_eq_iff
   957   expand_set_eq ~> set_eq_iff
   958   set_ext       ~> set_eqI
   959   nat_number    ~> eval_nat_numeral
   960 
   961 INCOMPATIBILITY.
   962 
   963 * Refactoring of code-generation specific operations in theory List:
   964 
   965   constants
   966     null ~> List.null
   967 
   968   facts
   969     mem_iff ~> member_def
   970     null_empty ~> null_def
   971 
   972 INCOMPATIBILITY.  Note that these were not supposed to be used
   973 regularly unless for striking reasons; their main purpose was code
   974 generation.
   975 
   976 Various operations from the Haskell prelude are used for generating
   977 Haskell code.
   978 
   979 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   980 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   981 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   982 
   983 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   984 "*" and "+" respectively.  INCOMPATIBILITY.
   985 
   986 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   987 "Sum_Type.Plus" instead.
   988 
   989 * Constant "split" has been merged with constant "prod_case"; names of
   990 ML functions, facts etc. involving split have been retained so far,
   991 though.  INCOMPATIBILITY.
   992 
   993 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   994 instead.  INCOMPATIBILITY.
   995 
   996 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   997 INCOMPATIBILITY.
   998 
   999 * Former theory Library/Enum is now part of the HOL-Main image.
  1000 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1001 referred to by its qualified name.
  1002 
  1003   enum    ~>  Enum.enum
  1004   nlists  ~>  Enum.nlists
  1005   product ~>  Enum.product
  1006 
  1007 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1008 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1009 INCOMPATIBILITY.
  1010 
  1011 * Theory Library/SetsAndFunctions has been split into
  1012 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1013 for instance definitions for functions; various improvements.
  1014 INCOMPATIBILITY.
  1015 
  1016 * Theory Library/Multiset provides stable quicksort implementation of
  1017 sort_key.
  1018 
  1019 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1020 INCOMPATIBILITY.
  1021 
  1022 * Session Multivariate_Analysis: introduced a type class for euclidean
  1023 space.  Most theorems are now stated in terms of euclidean spaces
  1024 instead of finite cartesian products.
  1025 
  1026   types
  1027     real ^ 'n ~>  'a::real_vector
  1028               ~>  'a::euclidean_space
  1029               ~>  'a::ordered_euclidean_space
  1030         (depends on your needs)
  1031 
  1032   constants
  1033      _ $ _        ~> _ $$ _
  1034      \<chi> x. _  ~> \<chi>\<chi> x. _
  1035      CARD('n)     ~> DIM('a)
  1036 
  1037 Also note that the indices are now natural numbers and not from some
  1038 finite type. Finite cartesian products of euclidean spaces, products
  1039 of euclidean spaces the real and complex numbers are instantiated to
  1040 be euclidean_spaces.  INCOMPATIBILITY.
  1041 
  1042 * Session Probability: introduced pextreal as positive extended real
  1043 numbers.  Use pextreal as value for measures.  Introduce the
  1044 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1045 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1046 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1047 
  1048 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1049 INCOMPATIBILITY.
  1050 
  1051 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1052 prove verification conditions generated by the SPARK Ada program
  1053 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1054 
  1055 
  1056 *** HOL-Algebra ***
  1057 
  1058 * Theorems for additive ring operations (locale abelian_monoid and
  1059 descendants) are generated by interpretation from their multiplicative
  1060 counterparts.  Names (in particular theorem names) have the mandatory
  1061 qualifier 'add'.  Previous theorem names are redeclared for
  1062 compatibility.
  1063 
  1064 * Structure "int_ring" is now an abbreviation (previously a
  1065 definition).  This fits more natural with advanced interpretations.
  1066 
  1067 
  1068 *** HOLCF ***
  1069 
  1070 * The domain package now runs in definitional mode by default: The
  1071 former command 'new_domain' is now called 'domain'.  To use the domain
  1072 package in its original axiomatic mode, use 'domain (unsafe)'.
  1073 INCOMPATIBILITY.
  1074 
  1075 * The new class "domain" is now the default sort.  Class "predomain"
  1076 is an unpointed version of "domain". Theories can be updated by
  1077 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1078 
  1079   'a::type ~> 'a::countable
  1080   'a::cpo  ~> 'a::predomain
  1081   'a::pcpo ~> 'a::domain
  1082 
  1083 * The old type class "rep" has been superseded by class "domain".
  1084 Accordingly, users of the definitional package must remove any
  1085 "default_sort rep" declarations.  INCOMPATIBILITY.
  1086 
  1087 * The domain package (definitional mode) now supports unpointed
  1088 predomain argument types, as long as they are marked 'lazy'. (Strict
  1089 arguments must be in class "domain".) For example, the following
  1090 domain definition now works:
  1091 
  1092   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1093 
  1094 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1095 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1096 'a option, and 'a list.  Additionally, it configures fixrec and the
  1097 domain package to work with these types.  For example:
  1098 
  1099   fixrec isInl :: "('a + 'b) u -> tr"
  1100     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1101 
  1102   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1103 
  1104 * The "(permissive)" option of fixrec has been replaced with a
  1105 per-equation "(unchecked)" option. See
  1106 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1107 
  1108 * The "bifinite" class no longer fixes a constant "approx"; the class
  1109 now just asserts that such a function exists.  INCOMPATIBILITY.
  1110 
  1111 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1112 defines an embedding of type 'a defl into udom by default; instances
  1113 of "bifinite" and "domain" classes are available in
  1114 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1115 
  1116 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1117 
  1118 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1119 
  1120 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1121 
  1122 * The function "cprod_map" has been renamed to "prod_map".
  1123 INCOMPATIBILITY.
  1124 
  1125 * The monadic bind operator on each powerdomain has new binder syntax
  1126 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1127 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1128 
  1129 * The infix syntax for binary union on each powerdomain has changed
  1130 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1131 syntax.  INCOMPATIBILITY.
  1132 
  1133 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1134 still supported as an input translation.
  1135 
  1136 * Renamed some theorems (the original names are also still available).
  1137 
  1138   expand_fun_below   ~> fun_below_iff
  1139   below_fun_ext      ~> fun_belowI
  1140   expand_cfun_eq     ~> cfun_eq_iff
  1141   ext_cfun           ~> cfun_eqI
  1142   expand_cfun_below  ~> cfun_below_iff
  1143   below_cfun_ext     ~> cfun_belowI
  1144   cont2cont_Rep_CFun ~> cont2cont_APP
  1145 
  1146 * The Abs and Rep functions for various types have changed names.
  1147 Related theorem names have also changed to match. INCOMPATIBILITY.
  1148 
  1149   Rep_CFun  ~> Rep_cfun
  1150   Abs_CFun  ~> Abs_cfun
  1151   Rep_Sprod ~> Rep_sprod
  1152   Abs_Sprod ~> Abs_sprod
  1153   Rep_Ssum  ~> Rep_ssum
  1154   Abs_Ssum  ~> Abs_ssum
  1155 
  1156 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1157 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1158 
  1159 * Various changes to bisimulation/coinduction with domain package:
  1160 
  1161   - Definitions of "bisim" constants no longer mention definedness.
  1162   - With mutual recursion, "bisim" predicate is now curried.
  1163   - With mutual recursion, each type gets a separate coind theorem.
  1164   - Variable names in bisim_def and coinduct rules have changed.
  1165 
  1166 INCOMPATIBILITY.
  1167 
  1168 * Case combinators generated by the domain package for type "foo" are
  1169 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1170 
  1171 * Several theorems have been renamed to more accurately reflect the
  1172 names of constants and types involved.  INCOMPATIBILITY.
  1173 
  1174   thelub_const    ~> lub_const
  1175   lub_const       ~> is_lub_const
  1176   thelubI         ~> lub_eqI
  1177   is_lub_lub      ~> is_lubD2
  1178   lubI            ~> is_lub_lub
  1179   unique_lub      ~> is_lub_unique
  1180   is_ub_lub       ~> is_lub_rangeD1
  1181   lub_bin_chain   ~> is_lub_bin_chain
  1182   lub_fun         ~> is_lub_fun
  1183   thelub_fun      ~> lub_fun
  1184   thelub_cfun     ~> lub_cfun
  1185   thelub_Pair     ~> lub_Pair
  1186   lub_cprod       ~> is_lub_prod
  1187   thelub_cprod    ~> lub_prod
  1188   minimal_cprod   ~> minimal_prod
  1189   inst_cprod_pcpo ~> inst_prod_pcpo
  1190   UU_I            ~> bottomI
  1191   compact_UU      ~> compact_bottom
  1192   deflation_UU    ~> deflation_bottom
  1193   finite_deflation_UU ~> finite_deflation_bottom
  1194 
  1195 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1196 
  1197   sq_ord_less_eq_trans ~> below_eq_trans
  1198   sq_ord_eq_less_trans ~> eq_below_trans
  1199   refl_less            ~> below_refl
  1200   trans_less           ~> below_trans
  1201   antisym_less         ~> below_antisym
  1202   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1203   box_less             ~> box_below
  1204   rev_trans_less       ~> rev_below_trans
  1205   not_less2not_eq      ~> not_below2not_eq
  1206   less_UU_iff          ~> below_UU_iff
  1207   flat_less_iff        ~> flat_below_iff
  1208   adm_less             ~> adm_below
  1209   adm_not_less         ~> adm_not_below
  1210   adm_compact_not_less ~> adm_compact_not_below
  1211   less_fun_def         ~> below_fun_def
  1212   expand_fun_less      ~> fun_below_iff
  1213   less_fun_ext         ~> fun_belowI
  1214   less_discr_def       ~> below_discr_def
  1215   discr_less_eq        ~> discr_below_eq
  1216   less_unit_def        ~> below_unit_def
  1217   less_cprod_def       ~> below_prod_def
  1218   prod_lessI           ~> prod_belowI
  1219   Pair_less_iff        ~> Pair_below_iff
  1220   fst_less_iff         ~> fst_below_iff
  1221   snd_less_iff         ~> snd_below_iff
  1222   expand_cfun_less     ~> cfun_below_iff
  1223   less_cfun_ext        ~> cfun_belowI
  1224   injection_less       ~> injection_below
  1225   less_up_def          ~> below_up_def
  1226   not_Iup_less         ~> not_Iup_below
  1227   Iup_less             ~> Iup_below
  1228   up_less              ~> up_below
  1229   Def_inject_less_eq   ~> Def_below_Def
  1230   Def_less_is_eq       ~> Def_below_iff
  1231   spair_less_iff       ~> spair_below_iff
  1232   less_sprod           ~> below_sprod
  1233   spair_less           ~> spair_below
  1234   sfst_less_iff        ~> sfst_below_iff
  1235   ssnd_less_iff        ~> ssnd_below_iff
  1236   fix_least_less       ~> fix_least_below
  1237   dist_less_one        ~> dist_below_one
  1238   less_ONE             ~> below_ONE
  1239   ONE_less_iff         ~> ONE_below_iff
  1240   less_sinlD           ~> below_sinlD
  1241   less_sinrD           ~> below_sinrD
  1242 
  1243 
  1244 *** FOL and ZF ***
  1245 
  1246 * All constant names are now qualified internally and use proper
  1247 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1248 
  1249 
  1250 *** ML ***
  1251 
  1252 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1253 Fail if the argument is false.  Due to inlining the source position of
  1254 failed assertions is included in the error output.
  1255 
  1256 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1257 text is in practice always evaluated with a stable theory checkpoint.
  1258 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1259 
  1260 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1261 the current context, not any accidental theory loader state as before.
  1262 Potential INCOMPATIBILITY, subtle change in semantics.
  1263 
  1264 * Syntax.pretty_priority (default 0) configures the required priority
  1265 of pretty-printed output and thus affects insertion of parentheses.
  1266 
  1267 * Syntax.default_root (default "any") configures the inner syntax
  1268 category (nonterminal symbol) for parsing of terms.
  1269 
  1270 * Former exception Library.UnequalLengths now coincides with
  1271 ListPair.UnequalLengths.
  1272 
  1273 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1274 main functionality is provided by structure Simplifier.
  1275 
  1276 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1277 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1278 almost all situations.
  1279 
  1280 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1281 See implementation manual for further details on exceptions in
  1282 Isabelle/ML.
  1283 
  1284 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1285 meaning.
  1286 
  1287 * Renamed structure PureThy to Pure_Thy and moved most of its
  1288 operations to structure Global_Theory, to emphasize that this is
  1289 rarely-used global-only stuff.
  1290 
  1291 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1292 instead (or tracing for high-volume output).
  1293 
  1294 * Configuration option show_question_marks only affects regular pretty
  1295 printing of types and terms, not raw Term.string_of_vname.
  1296 
  1297 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1298 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1299 @{thms} for most purposes.
  1300 
  1301 * ML structure Unsynchronized is never opened, not even in Isar
  1302 interaction mode as before.  Old Unsynchronized.set etc. have been
  1303 discontinued -- use plain := instead.  This should be *rare* anyway,
  1304 since modern tools always work via official context data, notably
  1305 configuration options.
  1306 
  1307 * Parallel and asynchronous execution requires special care concerning
  1308 interrupts.  Structure Exn provides some convenience functions that
  1309 avoid working directly with raw Interrupt.  User code must not absorb
  1310 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1311 followed by re-raising of the original exception.  Another common
  1312 source of mistakes are "handle _" patterns, which make the meaning of
  1313 the program subject to physical effects of the environment.
  1314 
  1315 
  1316 
  1317 New in Isabelle2009-2 (June 2010)
  1318 ---------------------------------
  1319 
  1320 *** General ***
  1321 
  1322 * Authentic syntax for *all* logical entities (type classes, type
  1323 constructors, term constants): provides simple and robust
  1324 correspondence between formal entities and concrete syntax.  Within
  1325 the parse tree / AST representations, "constants" are decorated by
  1326 their category (class, type, const) and spelled out explicitly with
  1327 their full internal name.
  1328 
  1329 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1330 and translations (translation rules and translation functions in ML).
  1331 Some hints on upgrading:
  1332 
  1333   - Many existing uses of 'syntax' and 'translations' can be replaced
  1334     by more modern 'type_notation', 'notation' and 'abbreviation',
  1335     which are independent of this issue.
  1336 
  1337   - 'translations' require markup within the AST; the term syntax
  1338     provides the following special forms:
  1339 
  1340       CONST c   -- produces syntax version of constant c from context
  1341       XCONST c  -- literally c, checked as constant from context
  1342       c         -- literally c, if declared by 'syntax'
  1343 
  1344     Plain identifiers are treated as AST variables -- occasionally the
  1345     system indicates accidental variables via the error "rhs contains
  1346     extra variables".
  1347 
  1348     Type classes and type constructors are marked according to their
  1349     concrete syntax.  Some old translations rules need to be written
  1350     for the "type" category, using type constructor application
  1351     instead of pseudo-term application of the default category
  1352     "logic".
  1353 
  1354   - 'parse_translation' etc. in ML may use the following
  1355     antiquotations:
  1356 
  1357       @{class_syntax c}   -- type class c within parse tree / AST
  1358       @{term_syntax c}    -- type constructor c within parse tree / AST
  1359       @{const_syntax c}   -- ML version of "CONST c" above
  1360       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1361 
  1362   - Literal types within 'typed_print_translations', i.e. those *not*
  1363     represented as pseudo-terms are represented verbatim.  Use @{class
  1364     c} or @{type_name c} here instead of the above syntax
  1365     antiquotations.
  1366 
  1367 Note that old non-authentic syntax was based on unqualified base
  1368 names, so all of the above "constant" names would coincide.  Recall
  1369 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1370 diagnose syntax problems.
  1371 
  1372 * Type constructors admit general mixfix syntax, not just infix.
  1373 
  1374 * Concrete syntax may be attached to local entities without a proof
  1375 body, too.  This works via regular mixfix annotations for 'fix',
  1376 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1377 similar to the 'notation' command in theory specifications.
  1378 
  1379 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1380 need to specify constant name and syntax separately.  Internal ML
  1381 datatype constructors have been renamed from InfixName to Infix etc.
  1382 Minor INCOMPATIBILITY.
  1383 
  1384 * Schematic theorem statements need to be explicitly markup as such,
  1385 via commands 'schematic_lemma', 'schematic_theorem',
  1386 'schematic_corollary'.  Thus the relevance of the proof is made
  1387 syntactically clear, which impacts performance in a parallel or
  1388 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1389 
  1390 * Use of cumulative prems via "!" in some proof methods has been
  1391 discontinued (old legacy feature).
  1392 
  1393 * References 'trace_simp' and 'debug_simp' have been replaced by
  1394 configuration options stored in the context. Enabling tracing (the
  1395 case of debugging is similar) in proofs works via
  1396 
  1397   using [[trace_simp = true]]
  1398 
  1399 Tracing is then active for all invocations of the simplifier in
  1400 subsequent goal refinement steps. Tracing may also still be enabled or
  1401 disabled via the ProofGeneral settings menu.
  1402 
  1403 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1404 'hide_fact' replace the former 'hide' KIND command.  Minor
  1405 INCOMPATIBILITY.
  1406 
  1407 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1408 more efficient than combinations with -q1 or -q2.
  1409 
  1410 
  1411 *** Pure ***
  1412 
  1413 * Proofterms record type-class reasoning explicitly, using the
  1414 "unconstrain" operation internally.  This eliminates all sort
  1415 constraints from a theorem and proof, introducing explicit
  1416 OFCLASS-premises.  On the proof term level, this operation is
  1417 automatically applied at theorem boundaries, such that closed proofs
  1418 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1419 inspect proof terms.
  1420 
  1421 * Local theory specifications may depend on extra type variables that
  1422 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1423 are added internally.  For example:
  1424 
  1425   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1426 
  1427 * Predicates of locales introduced by classes carry a mandatory
  1428 "class" prefix.  INCOMPATIBILITY.
  1429 
  1430 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1431 
  1432 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1433 'class' instead.
  1434 
  1435 * Command 'code_reflect' allows to incorporate generated ML code into
  1436 runtime environment; replaces immature code_datatype antiquotation.
  1437 INCOMPATIBILITY.
  1438 
  1439 * Code generator: simple concept for abstract datatypes obeying
  1440 invariants.
  1441 
  1442 * Code generator: details of internal data cache have no impact on the
  1443 user space functionality any longer.
  1444 
  1445 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1446 subgoals.  This is more appropriate for interpretations with 'where'.
  1447 INCOMPATIBILITY.
  1448 
  1449 * Command 'example_proof' opens an empty proof body.  This allows to
  1450 experiment with Isar, without producing any persistent result.
  1451 
  1452 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1453 within a local theory context, with explicit checking of the
  1454 constructors involved (in contrast to the raw 'syntax' versions).
  1455 
  1456 * Commands 'types' and 'typedecl' now work within a local theory
  1457 context -- without introducing dependencies on parameters or
  1458 assumptions, which is not possible in Isabelle/Pure.
  1459 
  1460 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1461 within a local theory context.  Minor INCOMPATIBILITY.
  1462 
  1463 
  1464 *** HOL ***
  1465 
  1466 * Command 'typedef' now works within a local theory context -- without
  1467 introducing dependencies on parameters or assumptions, which is not
  1468 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1469 contain multiple interpretations of local typedefs (with different
  1470 non-emptiness proofs), even in a global theory context.
  1471 
  1472 * New package for quotient types.  Commands 'quotient_type' and
  1473 'quotient_definition' may be used for defining types and constants by
  1474 quotient constructions.  An example is the type of integers created by
  1475 quotienting pairs of natural numbers:
  1476 
  1477   fun
  1478     intrel :: "(nat * nat) => (nat * nat) => bool"
  1479   where
  1480     "intrel (x, y) (u, v) = (x + v = u + y)"
  1481 
  1482   quotient_type int = "nat * nat" / intrel
  1483     by (auto simp add: equivp_def expand_fun_eq)
  1484 
  1485   quotient_definition
  1486     "0::int" is "(0::nat, 0::nat)"
  1487 
  1488 The method "lifting" can be used to lift of theorems from the
  1489 underlying "raw" type to the quotient type.  The example
  1490 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1491 construction and provides a reasoning infrastructure for finite sets.
  1492 
  1493 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1494 clash with new theory Quotient in Main HOL.
  1495 
  1496 * Moved the SMT binding into the main HOL session, eliminating
  1497 separate HOL-SMT session.
  1498 
  1499 * List membership infix mem operation is only an input abbreviation.
  1500 INCOMPATIBILITY.
  1501 
  1502 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1503 for future developements; former Library/Word.thy is still present in
  1504 the AFP entry RSAPPS.
  1505 
  1506 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1507 longer shadowed.  INCOMPATIBILITY.
  1508 
  1509 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1510 INCOMPATIBILITY.
  1511 
  1512 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1513 INCOMPATIBILITY.
  1514 
  1515 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1516 instead.  INCOMPATIBILITY.
  1517 
  1518 * Dropped several real-specific versions of lemmas about floor and
  1519 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1520 instead.  INCOMPATIBILITY.
  1521 
  1522   floor_number_of_eq         ~> floor_number_of
  1523   le_floor_eq_number_of      ~> number_of_le_floor
  1524   le_floor_eq_zero           ~> zero_le_floor
  1525   le_floor_eq_one            ~> one_le_floor
  1526   floor_less_eq_number_of    ~> floor_less_number_of
  1527   floor_less_eq_zero         ~> floor_less_zero
  1528   floor_less_eq_one          ~> floor_less_one
  1529   less_floor_eq_number_of    ~> number_of_less_floor
  1530   less_floor_eq_zero         ~> zero_less_floor
  1531   less_floor_eq_one          ~> one_less_floor
  1532   floor_le_eq_number_of      ~> floor_le_number_of
  1533   floor_le_eq_zero           ~> floor_le_zero
  1534   floor_le_eq_one            ~> floor_le_one
  1535   floor_subtract_number_of   ~> floor_diff_number_of
  1536   floor_subtract_one         ~> floor_diff_one
  1537   ceiling_number_of_eq       ~> ceiling_number_of
  1538   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1539   ceiling_le_zero_eq         ~> ceiling_le_zero
  1540   ceiling_le_eq_one          ~> ceiling_le_one
  1541   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1542   less_ceiling_eq_zero       ~> zero_less_ceiling
  1543   less_ceiling_eq_one        ~> one_less_ceiling
  1544   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1545   ceiling_less_eq_zero       ~> ceiling_less_zero
  1546   ceiling_less_eq_one        ~> ceiling_less_one
  1547   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1548   le_ceiling_eq_zero         ~> zero_le_ceiling
  1549   le_ceiling_eq_one          ~> one_le_ceiling
  1550   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1551   ceiling_subtract_one       ~> ceiling_diff_one
  1552 
  1553 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1554 application of the various fold combinators on finite sets.
  1555 
  1556 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1557 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1558 implementation.  INCOMPATIBILTY.
  1559 
  1560 * Theory Library/Coinductive_List has been removed -- superseded by
  1561 AFP/thys/Coinductive.
  1562 
  1563 * Theory PReal, including the type "preal" and related operations, has
  1564 been removed.  INCOMPATIBILITY.
  1565 
  1566 * Real: new development using Cauchy Sequences.
  1567 
  1568 * Split off theory "Big_Operators" containing setsum, setprod,
  1569 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1570 
  1571 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1572 "Int" etc.  INCOMPATIBILITY.
  1573 
  1574 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1575 
  1576 * New set of rules "ac_simps" provides combined assoc / commute
  1577 rewrites for all interpretations of the appropriate generic locales.
  1578 
  1579 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1580 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1581 appropriate and more consistent names suitable for name prefixes
  1582 within the HOL theories.  INCOMPATIBILITY.
  1583 
  1584 * Some generic constants have been put to appropriate theories:
  1585   - less_eq, less: Orderings
  1586   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1587   - inverse, divide: Rings
  1588 INCOMPATIBILITY.
  1589 
  1590 * More consistent naming of type classes involving orderings (and
  1591 lattices):
  1592 
  1593     lower_semilattice                   ~> semilattice_inf
  1594     upper_semilattice                   ~> semilattice_sup
  1595 
  1596     dense_linear_order                  ~> dense_linorder
  1597 
  1598     pordered_ab_group_add               ~> ordered_ab_group_add
  1599     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1600     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1601     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1602     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1603     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1604     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1605     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1606     pordered_comm_ring                  ~> ordered_comm_ring
  1607     pordered_comm_semiring              ~> ordered_comm_semiring
  1608     pordered_ring                       ~> ordered_ring
  1609     pordered_ring_abs                   ~> ordered_ring_abs
  1610     pordered_semiring                   ~> ordered_semiring
  1611 
  1612     ordered_ab_group_add                ~> linordered_ab_group_add
  1613     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1614     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1615     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1616     ordered_field                       ~> linordered_field
  1617     ordered_field_no_lb                 ~> linordered_field_no_lb
  1618     ordered_field_no_ub                 ~> linordered_field_no_ub
  1619     ordered_field_dense_linear_order    ~> dense_linordered_field
  1620     ordered_idom                        ~> linordered_idom
  1621     ordered_ring                        ~> linordered_ring
  1622     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1623     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1624     ordered_ring_strict                 ~> linordered_ring_strict
  1625     ordered_semidom                     ~> linordered_semidom
  1626     ordered_semiring                    ~> linordered_semiring
  1627     ordered_semiring_1                  ~> linordered_semiring_1
  1628     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1629     ordered_semiring_strict             ~> linordered_semiring_strict
  1630 
  1631   The following slightly odd type classes have been moved to a
  1632   separate theory Library/Lattice_Algebras:
  1633 
  1634     lordered_ab_group_add               ~> lattice_ab_group_add
  1635     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1636     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1637     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1638     lordered_ring                       ~> lattice_ring
  1639 
  1640 INCOMPATIBILITY.
  1641 
  1642 * Refined field classes:
  1643   - classes division_ring_inverse_zero, field_inverse_zero,
  1644     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1645     subsumes former division_by_zero class;
  1646   - numerous lemmas have been ported from field to division_ring.
  1647 INCOMPATIBILITY.
  1648 
  1649 * Refined algebra theorem collections:
  1650   - dropped theorem group group_simps, use algebra_simps instead;
  1651   - dropped theorem group ring_simps, use field_simps instead;
  1652   - proper theorem collection field_simps subsumes former theorem
  1653     groups field_eq_simps and field_simps;
  1654   - dropped lemma eq_minus_self_iff which is a duplicate for
  1655     equal_neg_zero.
  1656 INCOMPATIBILITY.
  1657 
  1658 * Theory Finite_Set and List: some lemmas have been generalized from
  1659 sets to lattices:
  1660 
  1661   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1662   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1663   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1664   union_Union_fold_union        ~> sup_Sup_fold_sup
  1665   Inter_fold_inter              ~> Inf_fold_inf
  1666   Union_fold_union              ~> Sup_fold_sup
  1667   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1668   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1669   INTER_fold_inter              ~> INFI_fold_inf
  1670   UNION_fold_union              ~> SUPR_fold_sup
  1671 
  1672 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1673 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1674 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1675 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1676 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1677 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1678 
  1679 * Reorganized theory Multiset: swapped notation of pointwise and
  1680 multiset order:
  1681 
  1682   - pointwise ordering is instance of class order with standard syntax
  1683     <= and <;
  1684   - multiset ordering has syntax <=# and <#; partial order properties
  1685     are provided by means of interpretation with prefix
  1686     multiset_order;
  1687   - less duplication, less historical organization of sections,
  1688     conversion from associations lists to multisets, rudimentary code
  1689     generation;
  1690   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1691     if needed.
  1692 
  1693 Renamed:
  1694 
  1695   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1696   multi_count_ext  ~>  multiset_ext
  1697   diff_union_inverse2  ~>  diff_union_cancelR
  1698 
  1699 INCOMPATIBILITY.
  1700 
  1701 * Theory Permutation: replaced local "remove" by List.remove1.
  1702 
  1703 * Code generation: ML and OCaml code is decorated with signatures.
  1704 
  1705 * Theory List: added transpose.
  1706 
  1707 * Library/Nat_Bijection.thy is a collection of bijective functions
  1708 between nat and other types, which supersedes the older libraries
  1709 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1710 
  1711   Constants:
  1712   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1713   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1714   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1715   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1716   Countable.pair_encode           ~> prod_encode
  1717   NatIso.prod2nat                 ~> prod_encode
  1718   NatIso.nat2prod                 ~> prod_decode
  1719   NatIso.sum2nat                  ~> sum_encode
  1720   NatIso.nat2sum                  ~> sum_decode
  1721   NatIso.list2nat                 ~> list_encode
  1722   NatIso.nat2list                 ~> list_decode
  1723   NatIso.set2nat                  ~> set_encode
  1724   NatIso.nat2set                  ~> set_decode
  1725 
  1726   Lemmas:
  1727   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1728   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1729   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1730   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1731   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1732   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1733   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1734   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1735   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1736   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1737   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1738   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1739   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1740 
  1741 * Sledgehammer:
  1742   - Renamed ATP commands:
  1743     atp_info     ~> sledgehammer running_atps
  1744     atp_kill     ~> sledgehammer kill_atps
  1745     atp_messages ~> sledgehammer messages
  1746     atp_minimize ~> sledgehammer minimize
  1747     print_atps   ~> sledgehammer available_atps
  1748     INCOMPATIBILITY.
  1749   - Added user's manual ("isabelle doc sledgehammer").
  1750   - Added option syntax and "sledgehammer_params" to customize
  1751     Sledgehammer's behavior.  See the manual for details.
  1752   - Modified the Isar proof reconstruction code so that it produces
  1753     direct proofs rather than proofs by contradiction.  (This feature
  1754     is still experimental.)
  1755   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1756     full-typed mode.
  1757   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1758 
  1759 * Nitpick:
  1760   - Added and implemented "binary_ints" and "bits" options.
  1761   - Added "std" option and implemented support for nonstandard models.
  1762   - Added and implemented "finitize" option to improve the precision
  1763     of infinite datatypes based on a monotonicity analysis.
  1764   - Added support for quotient types.
  1765   - Added support for "specification" and "ax_specification"
  1766     constructs.
  1767   - Added support for local definitions (for "function" and
  1768     "termination" proofs).
  1769   - Added support for term postprocessors.
  1770   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1771   - Improved efficiency of "destroy_constrs" optimization.
  1772   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1773     record getters.
  1774   - Fixed soundness bug related to higher-order constructors.
  1775   - Fixed soundness bug when "full_descrs" is enabled.
  1776   - Improved precision of set constructs.
  1777   - Added "atoms" option.
  1778   - Added cache to speed up repeated Kodkod invocations on the same
  1779     problems.
  1780   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1781     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1782     "SAT4J_Light".  INCOMPATIBILITY.
  1783   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1784     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1785   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1786 
  1787 * Method "induct" now takes instantiations of the form t, where t is not
  1788   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1789   If this is not intended, t has to be enclosed in parentheses.
  1790   By default, the equalities generated by definitional instantiations
  1791   are pre-simplified, which may cause parameters of inductive cases
  1792   to disappear, or may even delete some of the inductive cases.
  1793   Use "induct (no_simp)" instead of "induct" to restore the old
  1794   behaviour. The (no_simp) option is also understood by the "cases"
  1795   and "nominal_induct" methods, which now perform pre-simplification, too.
  1796   INCOMPATIBILITY.
  1797 
  1798 
  1799 *** HOLCF ***
  1800 
  1801 * Variable names in lemmas generated by the domain package have
  1802 changed; the naming scheme is now consistent with the HOL datatype
  1803 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1804 
  1805 * The domain package no longer defines the function "foo_copy" for
  1806 recursive domain "foo".  The reach lemma is now stated directly in
  1807 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1808 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1809 
  1810 * Most definedness lemmas generated by the domain package (previously
  1811 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1812 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1813 Proofs that used definedness lemmas as intro rules may break,
  1814 potential INCOMPATIBILITY.
  1815 
  1816 * Induction and casedist rules generated by the domain package now
  1817 declare proper case_names (one called "bottom", and one named for each
  1818 constructor).  INCOMPATIBILITY.
  1819 
  1820 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1821 rules are generated for each domain, INCOMPATIBILITY.
  1822 
  1823   foo_bar.reach       ~> foo.reach  bar.reach
  1824   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1825 
  1826 * Some lemmas generated by the domain package have been renamed for
  1827 consistency with the datatype package, INCOMPATIBILITY.
  1828 
  1829   foo.ind        ~> foo.induct
  1830   foo.finite_ind ~> foo.finite_induct
  1831   foo.coind      ~> foo.coinduct
  1832   foo.casedist   ~> foo.exhaust
  1833   foo.exhaust    ~> foo.nchotomy
  1834 
  1835 * For consistency with other definition packages, the fixrec package
  1836 now generates qualified theorem names, INCOMPATIBILITY.
  1837 
  1838   foo_simps  ~> foo.simps
  1839   foo_unfold ~> foo.unfold
  1840   foo_induct ~> foo.induct
  1841 
  1842 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1843 method and internal fixrec proofs now use the default simpset instead.
  1844 INCOMPATIBILITY.
  1845 
  1846 * The "contlub" predicate has been removed.  Proof scripts should use
  1847 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1848 
  1849 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1850 
  1851 * The constants cpair, cfst, and csnd have been removed in favor of
  1852 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1853 
  1854 
  1855 *** ML ***
  1856 
  1857 * Antiquotations for basic formal entities:
  1858 
  1859     @{class NAME}         -- type class
  1860     @{class_syntax NAME}  -- syntax representation of the above
  1861 
  1862     @{type_name NAME}     -- logical type
  1863     @{type_abbrev NAME}   -- type abbreviation
  1864     @{nonterminal NAME}   -- type of concrete syntactic category
  1865     @{type_syntax NAME}   -- syntax representation of any of the above
  1866 
  1867     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1868     @{const_abbrev NAME}  -- abbreviated constant
  1869     @{const_syntax NAME}  -- syntax representation of any of the above
  1870 
  1871 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1872 syntax constant (cf. 'syntax' command).
  1873 
  1874 * Antiquotation @{make_string} inlines a function to print arbitrary
  1875 values similar to the ML toplevel.  The result is compiler dependent
  1876 and may fall back on "?" in certain situations.
  1877 
  1878 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1879 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1880 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1881 not work with the asynchronous Isar document model.
  1882 
  1883 * Configuration options now admit dynamic default values, depending on
  1884 the context or even global references.
  1885 
  1886 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1887 uses an efficient external library if available (for Poly/ML).
  1888 
  1889 * Renamed some important ML structures, while keeping the old names
  1890 for some time as aliases within the structure Legacy:
  1891 
  1892   OuterKeyword  ~>  Keyword
  1893   OuterLex      ~>  Token
  1894   OuterParse    ~>  Parse
  1895   OuterSyntax   ~>  Outer_Syntax
  1896   PrintMode     ~>  Print_Mode
  1897   SpecParse     ~>  Parse_Spec
  1898   ThyInfo       ~>  Thy_Info
  1899   ThyLoad       ~>  Thy_Load
  1900   ThyOutput     ~>  Thy_Output
  1901   TypeInfer     ~>  Type_Infer
  1902 
  1903 Note that "open Legacy" simplifies porting of sources, but forgetting
  1904 to remove it again will complicate porting again in the future.
  1905 
  1906 * Most operations that refer to a global context are named
  1907 accordingly, e.g. Simplifier.global_context or
  1908 ProofContext.init_global.  There are some situations where a global
  1909 context actually works, but under normal circumstances one needs to
  1910 pass the proper local context through the code!
  1911 
  1912 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1913 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1914 Pretty.pp argument to merge, which is absent in the standard
  1915 Theory_Data version.
  1916 
  1917 * Sorts.certify_sort and derived "cert" operations for types and terms
  1918 no longer minimize sorts.  Thus certification at the boundary of the
  1919 inference kernel becomes invariant under addition of class relations,
  1920 which is an important monotonicity principle.  Sorts are now minimized
  1921 in the syntax layer only, at the boundary between the end-user and the
  1922 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1923 explicitly in rare situations.
  1924 
  1925 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1926 emphasize that this is in no way a standard operation.
  1927 INCOMPATIBILITY.
  1928 
  1929 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1930 usual for resolution.  Rare INCOMPATIBILITY.
  1931 
  1932 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1933 to emphasize that these only work in a global situation (which is
  1934 quite rare).
  1935 
  1936 * Curried take and drop in library.ML; negative length is interpreted
  1937 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1938 
  1939 * Proof terms: type substitutions on proof constants now use canonical
  1940 order of type variables.  INCOMPATIBILITY for tools working with proof
  1941 terms.
  1942 
  1943 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1944 may no longer carry premises.  User-level specifications are
  1945 transformed accordingly by Thm.add_axiom/add_def.
  1946 
  1947 
  1948 *** System ***
  1949 
  1950 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1951 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1952 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1953 
  1954 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1955 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1956 respectively.
  1957 
  1958 * Old lib/scripts/polyml-platform is superseded by the
  1959 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1960 variant, even on a 64 bit machine.  The following example setting
  1961 prefers 64 bit if available:
  1962 
  1963   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1964 
  1965 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1966 Isabelle/Scala layer for advanced prover interaction and integration.
  1967 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1968 component.
  1969 
  1970 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1971 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1972 similar to the default assignment of the document preparation system
  1973 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1974 provides some operations for direct access to the font without asking
  1975 the user for manual installation.
  1976 
  1977 
  1978 
  1979 New in Isabelle2009-1 (December 2009)
  1980 -------------------------------------
  1981 
  1982 *** General ***
  1983 
  1984 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1985 one backslash should be used, even in ML sources.
  1986 
  1987 
  1988 *** Pure ***
  1989 
  1990 * Locale interpretation propagates mixins along the locale hierarchy.
  1991 The currently only available mixins are the equations used to map
  1992 local definitions to terms of the target domain of an interpretation.
  1993 
  1994 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1995 loc" to print all interpretations of locale "loc" in the theory.
  1996 Interpretations in proofs are not shown.
  1997 
  1998 * Thoroughly revised locales tutorial.  New section on conditional
  1999 interpretation.
  2000 
  2001 * On instantiation of classes, remaining undefined class parameters
  2002 are formally declared.  INCOMPATIBILITY.
  2003 
  2004 
  2005 *** Document preparation ***
  2006 
  2007 * New generalized style concept for printing terms: @{foo (style) ...}
  2008 instead of @{foo_style style ...}  (old form is still retained for
  2009 backward compatibility).  Styles can be also applied for
  2010 antiquotations prop, term_type and typeof.
  2011 
  2012 
  2013 *** HOL ***
  2014 
  2015 * New proof method "smt" for a combination of first-order logic with
  2016 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2017 fixed-size bitvectors; there is also basic support for higher-order
  2018 features (esp. lambda abstractions).  It is an incomplete decision
  2019 procedure based on external SMT solvers using the oracle mechanism;
  2020 for the SMT solver Z3, this method is proof-producing.  Certificates
  2021 are provided to avoid calling the external solvers solely for
  2022 re-checking proofs.  Due to a remote SMT service there is no need for
  2023 installing SMT solvers locally.  See src/HOL/SMT.
  2024 
  2025 * New commands to load and prove verification conditions generated by
  2026 the Boogie program verifier or derived systems (e.g. the Verifying C
  2027 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2028 
  2029 * New counterexample generator tool 'nitpick' based on the Kodkod
  2030 relational model finder.  See src/HOL/Tools/Nitpick and
  2031 src/HOL/Nitpick_Examples.
  2032 
  2033 * New commands 'code_pred' and 'values' to invoke the predicate
  2034 compiler and to enumerate values of inductive predicates.
  2035 
  2036 * A tabled implementation of the reflexive transitive closure.
  2037 
  2038 * New implementation of quickcheck uses generic code generator;
  2039 default generators are provided for all suitable HOL types, records
  2040 and datatypes.  Old quickcheck can be re-activated importing theory
  2041 Library/SML_Quickcheck.
  2042 
  2043 * New testing tool Mirabelle for automated proof tools.  Applies
  2044 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2045 every proof step in a theory.  To be used in batch mode via the
  2046 "mirabelle" utility.
  2047 
  2048 * New proof method "sos" (sum of squares) for nonlinear real
  2049 arithmetic (originally due to John Harison). It requires theory
  2050 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2051 works well in practice on quantifier-free real arithmetic with +, -,
  2052 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2053 inequalities between polynomials.  It makes use of external
  2054 semidefinite programming solvers.  Method "sos" generates a
  2055 certificate that can be pasted into the proof thus avoiding the need
  2056 to call an external tool every time the proof is checked.  See
  2057 src/HOL/Library/Sum_Of_Squares.
  2058 
  2059 * New method "linarith" invokes existing linear arithmetic decision
  2060 procedure only.
  2061 
  2062 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2063 
  2064 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2065 Causes full type information to be output to the ATPs.  This slows
  2066 ATPs down considerably but eliminates a source of unsound "proofs"
  2067 that fail later.
  2068 
  2069 * New method "metisFT": A version of metis that uses full type
  2070 information in order to avoid failures of proof reconstruction.
  2071 
  2072 * New evaluator "approximate" approximates an real valued term using
  2073 the same method as the approximation method.
  2074 
  2075 * Method "approximate" now supports arithmetic expressions as
  2076 boundaries of intervals and implements interval splitting and Taylor
  2077 series expansion.
  2078 
  2079 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2080 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2081 
  2082 * New theory SupInf of the supremum and infimum operators for sets of
  2083 reals.
  2084 
  2085 * New theory Probability, which contains a development of measure
  2086 theory, eventually leading to Lebesgue integration and probability.
  2087 
  2088 * Extended Multivariate Analysis to include derivation and Brouwer's
  2089 fixpoint theorem.
  2090 
  2091 * Reorganization of number theory, INCOMPATIBILITY:
  2092   - new number theory development for nat and int, in theories Divides
  2093     and GCD as well as in new session Number_Theory
  2094   - some constants and facts now suffixed with _nat and _int
  2095     accordingly
  2096   - former session NumberTheory now named Old_Number_Theory, including
  2097     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2098   - moved theory Pocklington from src/HOL/Library to
  2099     src/HOL/Old_Number_Theory
  2100 
  2101 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2102 lcm of finite and infinite sets. It is shown that they form a complete
  2103 lattice.
  2104 
  2105 * Class semiring_div requires superclass no_zero_divisors and proof of
  2106 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2107 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2108 generalized to class semiring_div, subsuming former theorems
  2109 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2110 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2111 INCOMPATIBILITY.
  2112 
  2113 * Refinements to lattice classes and sets:
  2114   - less default intro/elim rules in locale variant, more default
  2115     intro/elim rules in class variant: more uniformity
  2116   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2117     le_inf_iff
  2118   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2119     sup_aci)
  2120   - renamed ACI to inf_sup_aci
  2121   - new class "boolean_algebra"
  2122   - class "complete_lattice" moved to separate theory
  2123     "Complete_Lattice"; corresponding constants (and abbreviations)
  2124     renamed and with authentic syntax:
  2125     Set.Inf ~>    Complete_Lattice.Inf
  2126     Set.Sup ~>    Complete_Lattice.Sup
  2127     Set.INFI ~>   Complete_Lattice.INFI
  2128     Set.SUPR ~>   Complete_Lattice.SUPR
  2129     Set.Inter ~>  Complete_Lattice.Inter
  2130     Set.Union ~>  Complete_Lattice.Union
  2131     Set.INTER ~>  Complete_Lattice.INTER
  2132     Set.UNION ~>  Complete_Lattice.UNION
  2133   - authentic syntax for
  2134     Set.Pow
  2135     Set.image
  2136   - mere abbreviations:
  2137     Set.empty               (for bot)
  2138     Set.UNIV                (for top)
  2139     Set.inter               (for inf, formerly Set.Int)
  2140     Set.union               (for sup, formerly Set.Un)
  2141     Complete_Lattice.Inter  (for Inf)
  2142     Complete_Lattice.Union  (for Sup)
  2143     Complete_Lattice.INTER  (for INFI)
  2144     Complete_Lattice.UNION  (for SUPR)
  2145   - object-logic definitions as far as appropriate
  2146 
  2147 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2148 Un_subset_iff are explicitly deleted as default simp rules; then also
  2149 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2150 deleted to achieve the desired effect.
  2151 
  2152 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2153 rules by default any longer; the same applies to min_max.inf_absorb1
  2154 etc.  INCOMPATIBILITY.
  2155 
  2156 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2157 pred_set_conv by default.  INCOMPATIBILITY.
  2158 
  2159 * Power operations on relations and functions are now one dedicated
  2160 constant "compow" with infix syntax "^^".  Power operation on
  2161 multiplicative monoids retains syntax "^" and is now defined generic
  2162 in class power.  INCOMPATIBILITY.
  2163 
  2164 * Relation composition "R O S" now has a more standard argument order:
  2165 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2166 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2167 break, since the O_assoc rule was not rewritten like this.  Fix using
  2168 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2169 
  2170 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2171 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2172 INCOMPATIBILITY.
  2173 
  2174 * Most rules produced by inductive and datatype package have mandatory
  2175 prefixes.  INCOMPATIBILITY.
  2176 
  2177 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2178 the attribute of the same name.  Each of the theorems in the list
  2179 DERIV_intros assumes composition with an additional function and
  2180 matches a variable to the derivative, which has to be solved by the
  2181 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2182 of most elementary terms.  Former Maclauren.DERIV_tac and
  2183 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2184 INCOMPATIBILITY.
  2185 
  2186 * Code generator attributes follow the usual underscore convention:
  2187     code_unfold     replaces    code unfold
  2188     code_post       replaces    code post
  2189     etc.
  2190   INCOMPATIBILITY.
  2191 
  2192 * Renamed methods:
  2193     sizechange -> size_change
  2194     induct_scheme -> induction_schema
  2195   INCOMPATIBILITY.
  2196 
  2197 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2198 INCOMPATIBILITY, use "undefined" directly.
  2199 
  2200 * Renamed theorems:
  2201     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2202     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2203     Suc_plus1 -> Suc_eq_plus1
  2204     *anti_sym -> *antisym*
  2205     vector_less_eq_def -> vector_le_def
  2206   INCOMPATIBILITY.
  2207 
  2208 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2209 INCOMPATIBILITY.
  2210 
  2211 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2212 INCOMPATIBILITY.
  2213 
  2214 
  2215 *** HOLCF ***
  2216 
  2217 * Theory Representable defines a class "rep" of domains that are
  2218 representable (via an ep-pair) in the universal domain type "udom".
  2219 Instances are provided for all type constructors defined in HOLCF.
  2220 
  2221 * The 'new_domain' command is a purely definitional version of the
  2222 domain package, for representable domains.  Syntax is identical to the
  2223 old domain package.  The 'new_domain' package also supports indirect
  2224 recursion using previously-defined type constructors.  See
  2225 src/HOLCF/ex/New_Domain.thy for examples.
  2226 
  2227 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2228 on the left-hand side of an equation, and then performs
  2229 simplification.  Rewriting is done using rules declared with the
  2230 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2231 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2232 
  2233 * The pattern-match compiler in 'fixrec' can now handle constructors
  2234 with HOL function types.  Pattern-match combinators for the Pair
  2235 constructor are pre-configured.
  2236 
  2237 * The 'fixrec' package now produces better fixed-point induction rules
  2238 for mutually-recursive definitions:  Induction rules have conclusions
  2239 of the form "P foo bar" instead of "P <foo, bar>".
  2240 
  2241 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2242 been renamed to "below".  The name "below" now replaces "less" in many
  2243 theorem names.  (Legacy theorem names using "less" are still supported
  2244 as well.)
  2245 
  2246 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2247 patterns can be used to generate strictness rules, or to make
  2248 functions more strict (much like the bang-patterns supported by the
  2249 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2250 examples.
  2251 
  2252 
  2253 *** ML ***
  2254 
  2255 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2256 errors and run-time exceptions, including detailed source positions.
  2257 
  2258 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2259 identified entries, with some additional information such as source
  2260 position, logical grouping etc.
  2261 
  2262 * Theory and context data is now introduced by the simplified and
  2263 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2264 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2265 copy operation) is still available for some time.
  2266 
  2267 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2268 provides a high-level programming interface to synchronized state
  2269 variables with atomic update.  This works via pure function
  2270 application within a critical section -- its runtime should be as
  2271 short as possible; beware of deadlocks if critical code is nested,
  2272 either directly or indirectly via other synchronized variables!
  2273 
  2274 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2275 wraps raw ML references, explicitly indicating their non-thread-safe
  2276 behaviour.  The Isar toplevel keeps this structure open, to
  2277 accommodate Proof General as well as quick and dirty interactive
  2278 experiments with references.
  2279 
  2280 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2281 parallel tactical reasoning.
  2282 
  2283 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2284 are similar to SUBPROOF, but are slightly more flexible: only the
  2285 specified parts of the subgoal are imported into the context, and the
  2286 body tactic may introduce new subgoals and schematic variables.
  2287 
  2288 * Old tactical METAHYPS, which does not observe the proof context, has
  2289 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2290 or Subgoal.FOCUS etc.
  2291 
  2292 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2293 functors have their own ML name space there is no point to mark them
  2294 separately.)  Minor INCOMPATIBILITY.
  2295 
  2296 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2297 
  2298 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2299 INCOMPATIBILITY.
  2300 
  2301 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2302 mode, which avoids critical setmp.
  2303 
  2304 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2305 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2306 Attrib/Method.setup introduced in Isabelle2009.
  2307 
  2308 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2309 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2310 last resort.  INCOMPATIBILITY.
  2311 
  2312 * Display.pretty_thm now requires a proper context (cf. former
  2313 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2314 or even Display.pretty_thm_without_context as last resort.
  2315 INCOMPATIBILITY.
  2316 
  2317 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2318 Syntax.pretty_typ/term directly, preferably with proper context
  2319 instead of global theory.
  2320 
  2321 
  2322 *** System ***
  2323 
  2324 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2325 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2326 usedir option -q.
  2327 
  2328 * Support for additional "Isabelle components" via etc/components, see
  2329 also the system manual.
  2330 
  2331 * The isabelle makeall tool now operates on all components with
  2332 IsaMakefile, not just hardwired "logics".
  2333 
  2334 * Removed "compress" option from isabelle-process and isabelle usedir;
  2335 this is always enabled.
  2336 
  2337 * Discontinued support for Poly/ML 4.x versions.
  2338 
  2339 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2340 on a given logic image.  This requires the lighttpd webserver and is
  2341 currently supported on Linux only.
  2342 
  2343 
  2344 
  2345 New in Isabelle2009 (April 2009)
  2346 --------------------------------
  2347 
  2348 *** General ***
  2349 
  2350 * Simplified main Isabelle executables, with less surprises on
  2351 case-insensitive file-systems (such as Mac OS).
  2352 
  2353   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2354     "isatool."
  2355 
  2356   - The former "isabelle" alias for "isabelle-process" has been
  2357     removed (should rarely occur to regular users).
  2358 
  2359   - The former "isabelle-interface" and its alias "Isabelle" have been
  2360     removed (interfaces are now regular Isabelle tools).
  2361 
  2362 Within scripts and make files, the Isabelle environment variables
  2363 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2364 respectively.  (The latter are still available as legacy feature.)
  2365 
  2366 The old isabelle-interface wrapper could react in confusing ways if
  2367 the interface was uninstalled or changed otherwise.  Individual
  2368 interface tool configuration is now more explicit, see also the
  2369 Isabelle system manual.  In particular, Proof General is now available
  2370 via "isabelle emacs".
  2371 
  2372 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2373 purge installed copies of Isabelle executables and re-run "isabelle
  2374 install -p ...", or use symlinks.
  2375 
  2376 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2377 old ~/isabelle, which was slightly non-standard and apt to cause
  2378 surprises on case-insensitive file-systems (such as Mac OS).
  2379 
  2380 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2381 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2382 care is required when using older releases of Isabelle.  Note that
  2383 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2384 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2385 
  2386 * Proofs of fully specified statements are run in parallel on
  2387 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2388 a regular 4-core machine, if the initial heap space is made reasonably
  2389 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2390 
  2391 * The main reference manuals ("isar-ref", "implementation", and
  2392 "system") have been updated and extended.  Formally checked references
  2393 as hyperlinks are now available uniformly.
  2394 
  2395 
  2396 *** Pure ***
  2397 
  2398 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2399 respects.  The most important changes are listed below.  See the
  2400 Tutorial on Locales ("locales" manual) for details.
  2401 
  2402 - In locale expressions, instantiation replaces renaming.  Parameters
  2403 must be declared in a for clause.  To aid compatibility with previous
  2404 parameter inheritance, in locale declarations, parameters that are not
  2405 'touched' (instantiation position "_" or omitted) are implicitly added
  2406 with their syntax at the beginning of the for clause.
  2407 
  2408 - Syntax from abbreviations and definitions in locales is available in
  2409 locale expressions and context elements.  The latter is particularly
  2410 useful in locale declarations.
  2411 
  2412 - More flexible mechanisms to qualify names generated by locale
  2413 expressions.  Qualifiers (prefixes) may be specified in locale
  2414 expressions, and can be marked as mandatory (syntax: "name!:") or
  2415 optional (syntax "name?:").  The default depends for plain "name:"
  2416 depends on the situation where a locale expression is used: in
  2417 commands 'locale' and 'sublocale' prefixes are optional, in
  2418 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2419 implicit qualifiers derived from the parameter names of a locale are
  2420 no longer generated.
  2421 
  2422 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2423 instantiation clause in "interpretation" and "interpret" (square
  2424 brackets) is no longer available.  Use locale expressions.
  2425 
  2426 - When converting proof scripts, mandatory qualifiers in
  2427 'interpretation' and 'interpret' should be retained by default, even
  2428 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2429 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2430 in locale expressions range over a single locale instance only.
  2431 
  2432 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2433 In existing theorem specifications replace the includes element by the
  2434 respective context elements of the included locale, omitting those
  2435 that are already present in the theorem specification.  Multiple
  2436 assume elements of a locale should be replaced by a single one
  2437 involving the locale predicate.  In the proof body, declarations (most
  2438 notably theorems) may be regained by interpreting the respective
  2439 locales in the proof context as required (command "interpret").
  2440 
  2441 If using "includes" in replacement of a target solely because the
  2442 parameter types in the theorem are not as general as in the target,
  2443 consider declaring a new locale with additional type constraints on
  2444 the parameters (context element "constrains").
  2445 
  2446 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2447 
  2448 - Locale interpretation commands no longer attempt to simplify goal.
  2449 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2450 methods intro_locales and unfold_locales to clarify.
  2451 
  2452 - Locale interpretation commands no longer accept interpretation
  2453 attributes.  INCOMPATIBILITY.
  2454 
  2455 * Class declaration: so-called "base sort" must not be given in import
  2456 list any longer, but is inferred from the specification.  Particularly
  2457 in HOL, write
  2458 
  2459     class foo = ...
  2460 
  2461 instead of
  2462 
  2463     class foo = type + ...
  2464 
  2465 * Class target: global versions of theorems stemming do not carry a
  2466 parameter prefix any longer.  INCOMPATIBILITY.
  2467 
  2468 * Class 'instance' command no longer accepts attached definitions.
  2469 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2470 
  2471 * Recovered hiding of consts, which was accidentally broken in
  2472 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2473 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2474 
  2475 * Slightly more coherent Pure syntax, with updated documentation in
  2476 isar-ref manual.  Removed locales meta_term_syntax and
  2477 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2478 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2479 directly in regular applications.
  2480 
  2481 * There is a new syntactic category "float_const" for signed decimal
  2482 fractions (e.g. 123.45 or -123.45).
  2483 
  2484 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2485 interface with 'setup' command instead.
  2486 
  2487 * Command 'local_setup' is similar to 'setup', but operates on a local
  2488 theory context.
  2489 
  2490 * The 'axiomatization' command now only works within a global theory
  2491 context.  INCOMPATIBILITY.
  2492 
  2493 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2494 hypotheses.  Sorts required in the course of reasoning need to be
  2495 covered by the constraints in the initial statement, completed by the
  2496 type instance information of the background theory.  Non-trivial sort
  2497 hypotheses, which rarely occur in practice, may be specified via
  2498 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2499 
  2500   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2501 
  2502 The result contains an implicit sort hypotheses as before --
  2503 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2504 normalization.
  2505 
  2506 * Generalized Isar history, with support for linear undo, direct state
  2507 addressing etc.
  2508 
  2509 * Changed defaults for unify configuration options:
  2510 
  2511   unify_trace_bound = 50 (formerly 25)
  2512   unify_search_bound = 60 (formerly 30)
  2513 
  2514 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2515 
  2516   a) On theory merge, the last set of code equations for a particular
  2517      constant is taken (in accordance with the policy applied by other
  2518      parts of the code generator framework).
  2519 
  2520   b) Code equations stemming from explicit declarations (e.g. code
  2521      attribute) gain priority over default code equations stemming
  2522      from definition, primrec, fun etc.
  2523 
  2524 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2525 
  2526 * Unified theorem tables for both code generators.  Thus [code
  2527 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2528 
  2529 * Command 'find_consts' searches for constants based on type and name
  2530 patterns, e.g.
  2531 
  2532     find_consts "_ => bool"
  2533 
  2534 By default, matching is against subtypes, but it may be restricted to
  2535 the whole type.  Searching by name is possible.  Multiple queries are
  2536 conjunctive and queries may be negated by prefixing them with a
  2537 hyphen:
  2538 
  2539     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2540 
  2541 * New 'find_theorems' criterion "solves" matches theorems that
  2542 directly solve the current goal (modulo higher-order unification).
  2543 
  2544 * Auto solve feature for main theorem statements: whenever a new goal
  2545 is stated, "find_theorems solves" is called; any theorems that could
  2546 solve the lemma directly are listed as part of the goal state.
  2547 Cf. associated options in Proof General Isabelle settings menu,
  2548 enabled by default, with reasonable timeout for pathological cases of
  2549 higher-order unification.
  2550 
  2551 
  2552 *** Document preparation ***
  2553 
  2554 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2555 demanding keyword 'by' and supporting the full method expression
  2556 syntax just like the Isar command 'by'.
  2557 
  2558 
  2559 *** HOL ***
  2560 
  2561 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2562 points Main and Complex_Main remain as before.
  2563 
  2564 * Logic image HOL-Plain provides a minimal HOL with the most important
  2565 tools available (inductive, datatype, primrec, ...).  This facilitates
  2566 experimentation and tool development.  Note that user applications
  2567 (and library theories) should never refer to anything below theory
  2568 Main, as before.
  2569 
  2570 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2571 experimentation due to shorter build times.
  2572 
  2573 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2574 were previously part of former HOL-Complex.  Entry point Hyperreal
  2575 remains valid, but theories formerly using Complex_Main should now use
  2576 new entry point Hypercomplex.
  2577 
  2578 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2579 Posix processes.  Avoids potentially expensive forking of the ML
  2580 process.  New thread-based implementation also works on non-Unix
  2581 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2582 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2583 commands are covered in the isar-ref manual.
  2584 
  2585 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2586 sledgehammer without local ATP installation (Vampire etc.). Other
  2587 provers may be included via suitable ML wrappers, see also
  2588 src/HOL/ATP_Linkup.thy.
  2589 
  2590 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2591 menu.
  2592 
  2593 * The metis method no longer fails because the theorem is too trivial
  2594 (contains the empty clause).
  2595 
  2596 * The metis method now fails in the usual manner, rather than raising
  2597 an exception, if it determines that it cannot prove the theorem.
  2598 
  2599 * Method "coherent" implements a prover for coherent logic (see also
  2600 src/Tools/coherent.ML).
  2601 
  2602 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2603 "undefined" is the right choice to replace "arbitrary", though
  2604 logically there is no difference.  INCOMPATIBILITY.
  2605 
  2606 * Command "value" now integrates different evaluation mechanisms.  The
  2607 result of the first successful evaluation mechanism is printed.  In
  2608 square brackets a particular named evaluation mechanisms may be
  2609 specified (currently, [SML], [code] or [nbe]).  See further
  2610 src/HOL/ex/Eval_Examples.thy.
  2611 
  2612 * Normalization by evaluation now allows non-leftlinear equations.
  2613 Declare with attribute [code nbe].
  2614 
  2615 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2616 as the structured Isar versions "cases" and "induct", cf. the
  2617 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2618 are now presented as a list of individual projections
  2619 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2620 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2621 rare situations a different rule is selected --- notably nested tuple
  2622 elimination instead of former prod.exhaust: use explicit (case_tac t
  2623 rule: prod.exhaust) here.
  2624 
  2625 * Attributes "cases", "induct", "coinduct" support "del" option.
  2626 
  2627 * Removed fact "case_split_thm", which duplicates "case_split".
  2628 
  2629 * The option datatype has been moved to a new theory Option.  Renamed
  2630 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2631 
  2632 * New predicate "strict_mono" classifies strict functions on partial
  2633 orders.  With strict functions on linear orders, reasoning about
  2634 (in)equalities is facilitated by theorems "strict_mono_eq",
  2635 "strict_mono_less_eq" and "strict_mono_less".
  2636 
  2637 * Some set operations are now proper qualified constants with
  2638 authentic syntax.  INCOMPATIBILITY:
  2639 
  2640     op Int ~>   Set.Int
  2641     op Un ~>    Set.Un
  2642     INTER ~>    Set.INTER
  2643     UNION ~>    Set.UNION
  2644     Inter ~>    Set.Inter
  2645     Union ~>    Set.Union
  2646     {} ~>       Set.empty
  2647     UNIV ~>     Set.UNIV
  2648 
  2649 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2650 theory Set.
  2651 
  2652 * Auxiliary class "itself" has disappeared -- classes without any
  2653 parameter are treated as expected by the 'class' command.
  2654 
  2655 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2656 
  2657 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2658 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2659 
  2660 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2661 method "approximation".  It proves formulas on real values by using
  2662 interval arithmetic.  In the formulas are also the transcendental
  2663 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2664 allowed. For examples see
  2665 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2666 
  2667 * Theory "Reflection" now resides in HOL/Library.
  2668 
  2669 * Entry point to Word library now simply named "Word".
  2670 INCOMPATIBILITY.
  2671 
  2672 * Made source layout more coherent with logical distribution
  2673 structure:
  2674 
  2675     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2676     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2677     src/HOL/Library/GCD.thy ~> src/HOL/
  2678     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2679     src/HOL/Library/Parity.thy ~> src/HOL/
  2680     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2681     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2682     src/HOL/Real/Lubs.thy ~> src/HOL/
  2683     src/HOL/Real/PReal.thy ~> src/HOL/
  2684     src/HOL/Real/Rational.thy ~> src/HOL/
  2685     src/HOL/Real/RComplete.thy ~> src/HOL/
  2686     src/HOL/Real/RealDef.thy ~> src/HOL/
  2687     src/HOL/Real/RealPow.thy ~> src/HOL/
  2688     src/HOL/Real/Real.thy ~> src/HOL/
  2689     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2690     src/HOL/Complex/Complex.thy ~> src/HOL/
  2691     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2692     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2693     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2694     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2695     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2696     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2697     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2698     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2699     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2700     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2701     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2702     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2703     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2704     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2705     src/HOL/Real/Float ~> src/HOL/Library/
  2706     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2707     src/HOL/Real/RealVector.thy ~> src/HOL/
  2708 
  2709     src/HOL/arith_data.ML ~> src/HOL/Tools
  2710     src/HOL/hologic.ML ~> src/HOL/Tools
  2711     src/HOL/simpdata.ML ~> src/HOL/Tools
  2712     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2713     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2714     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2715     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2716     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2717     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2718     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2719 
  2720     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2721     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2722     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2723     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2724     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2725     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2726 
  2727 * If methods "eval" and "evaluation" encounter a structured proof
  2728 state with !!/==>, only the conclusion is evaluated to True (if
  2729 possible), avoiding strange error messages.
  2730 
  2731 * Method "sizechange" automates termination proofs using (a
  2732 modification of) the size-change principle.  Requires SAT solver.  See
  2733 src/HOL/ex/Termination.thy for examples.
  2734 
  2735 * Simplifier: simproc for let expressions now unfolds if bound
  2736 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2737 
  2738 * Method "arith": Linear arithmetic now ignores all inequalities when
  2739 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2740 
  2741 * New attribute "arith" for facts that should always be used
  2742 automatically by arithmetic. It is intended to be used locally in
  2743 proofs, e.g.
  2744 
  2745   assumes [arith]: "x > 0"
  2746 
  2747 Global usage is discouraged because of possible performance impact.
  2748 
  2749 * New classes "top" and "bot" with corresponding operations "top" and
  2750 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2751 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2752 
  2753 * Changed definition lemma "less_fun_def" in order to provide an
  2754 instance for preorders on functions; use lemma "less_le" instead.
  2755 INCOMPATIBILITY.
  2756 
  2757 * Theory Orderings: class "wellorder" moved here, with explicit
  2758 induction rule "less_induct" as assumption.  For instantiation of
  2759 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2760 INCOMPATIBILITY.
  2761 
  2762 * Theory Orderings: added class "preorder" as superclass of "order".
  2763 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2764 etc. slightly changed.  Some theorems named order_class.* now named
  2765 preorder_class.*.
  2766 
  2767 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2768 "diag" to "Id_on".
  2769 
  2770 * Theory Finite_Set: added a new fold combinator of type
  2771 
  2772   ('a => 'b => 'b) => 'b => 'a set => 'b
  2773 
  2774 Occasionally this is more convenient than the old fold combinator
  2775 which is now defined in terms of the new one and renamed to
  2776 fold_image.
  2777 
  2778 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2779 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2780 extended with further lemmas!).  At the moment both still exist but
  2781 the former will disappear at some point.
  2782 
  2783 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2784 class recpower.  Type-specific simp rules for various recpower types
  2785 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2786 
  2787 rat_power_0    -> power_0
  2788 rat_power_Suc  -> power_Suc
  2789 realpow_0      -> power_0
  2790 realpow_Suc    -> power_Suc
  2791 complexpow_0   -> power_0
  2792 complexpow_Suc -> power_Suc
  2793 power_poly_0   -> power_0
  2794 power_poly_Suc -> power_Suc
  2795 
  2796 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2797 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2798 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2799 of lemmas from Divides has been generalized from nat to class
  2800 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2801 renames resulting from duplicate elimination:
  2802 
  2803     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2804     zero_dvd_iff ~>         dvd_0_left_iff
  2805     dvd_0 ~>                dvd_0_right
  2806     DIVISION_BY_ZERO_DIV ~> div_by_0
  2807     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2808     mult_div ~>             div_mult_self2_is_id
  2809     mult_mod ~>             mod_mult_self2_is_0
  2810 
  2811 * Theory IntDiv: removed many lemmas that are instances of class-based
  2812 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2813 rename old lemmas as follows:
  2814 
  2815 dvd_diff               -> nat_dvd_diff
  2816 dvd_zminus_iff         -> dvd_minus_iff
  2817 mod_add1_eq            -> mod_add_eq
  2818 mod_mult1_eq           -> mod_mult_right_eq
  2819 mod_mult1_eq'          -> mod_mult_left_eq
  2820 mod_mult_distrib_mod   -> mod_mult_eq
  2821 nat_mod_add_left_eq    -> mod_add_left_eq
  2822 nat_mod_add_right_eq   -> mod_add_right_eq
  2823 nat_mod_div_trivial    -> mod_div_trivial
  2824 nat_mod_mod_trivial    -> mod_mod_trivial
  2825 zdiv_zadd_self1        -> div_add_self1
  2826 zdiv_zadd_self2        -> div_add_self2
  2827 zdiv_zmult_self1       -> div_mult_self2_is_id
  2828 zdiv_zmult_self2       -> div_mult_self1_is_id
  2829 zdvd_triv_left         -> dvd_triv_left
  2830 zdvd_triv_right        -> dvd_triv_right
  2831 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2832 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2833 zmod_zadd_left_eq      -> mod_add_left_eq
  2834 zmod_zadd_right_eq     -> mod_add_right_eq
  2835 zmod_zadd_self1        -> mod_add_self1
  2836 zmod_zadd_self2        -> mod_add_self2
  2837 zmod_zadd1_eq          -> mod_add_eq
  2838 zmod_zdiff1_eq         -> mod_diff_eq
  2839 zmod_zdvd_zmod         -> mod_mod_cancel
  2840 zmod_zmod_cancel       -> mod_mod_cancel
  2841 zmod_zmult_self1       -> mod_mult_self2_is_0
  2842 zmod_zmult_self2       -> mod_mult_self1_is_0
  2843 zmod_1                 -> mod_by_1
  2844 zdiv_1                 -> div_by_1
  2845 zdvd_abs1              -> abs_dvd_iff
  2846 zdvd_abs2              -> dvd_abs_iff
  2847 zdvd_refl              -> dvd_refl
  2848 zdvd_trans             -> dvd_trans
  2849 zdvd_zadd              -> dvd_add
  2850 zdvd_zdiff             -> dvd_diff
  2851 zdvd_zminus_iff        -> dvd_minus_iff
  2852 zdvd_zminus2_iff       -> minus_dvd_iff
  2853 zdvd_zmultD            -> dvd_mult_right
  2854 zdvd_zmultD2           -> dvd_mult_left
  2855 zdvd_zmult_mono        -> mult_dvd_mono
  2856 zdvd_0_right           -> dvd_0_right
  2857 zdvd_0_left            -> dvd_0_left_iff
  2858 zdvd_1_left            -> one_dvd
  2859 zminus_dvd_iff         -> minus_dvd_iff
  2860 
  2861 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2862 
  2863 * The real numbers offer decimal input syntax: 12.34 is translated
  2864 into 1234/10^2. This translation is not reversed upon output.
  2865 
  2866 * Theory Library/Polynomial defines an abstract type 'a poly of
  2867 univariate polynomials with coefficients of type 'a.  In addition to
  2868 the standard ring operations, it also supports div and mod.  Code
  2869 generation is also supported, using list-style constructors.
  2870 
  2871 * Theory Library/Inner_Product defines a class of real_inner for real
  2872 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2873 => real.  Class real_inner is a subclass of real_normed_vector from
  2874 theory RealVector.
  2875 
  2876 * Theory Library/Product_Vector provides instances for the product
  2877 type 'a * 'b of several classes from RealVector and Inner_Product.
  2878 Definitions of addition, subtraction, scalar multiplication, norms,
  2879 and inner products are included.
  2880 
  2881 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2882 addition to the field operations, numerals and case syntax are also
  2883 supported.
  2884 
  2885 * Theory Library/Diagonalize provides constructive version of Cantor's
  2886 first diagonalization argument.
  2887 
  2888 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2889 zlcm (for int); carried together from various gcd/lcm developements in
  2890 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2891 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2892 may recover tupled syntax as follows:
  2893 
  2894     hide (open) const gcd
  2895     abbreviation gcd where
  2896       "gcd == (%(a, b). GCD.gcd a b)"
  2897     notation (output)
  2898       GCD.gcd ("gcd '(_, _')")
  2899 
  2900 The same works for lcm, zgcd, zlcm.
  2901 
  2902 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2903 instantiations for algebraic structures.  Removed some duplicate
  2904 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2905 
  2906 * ML antiquotation @{code} takes a constant as argument and generates
  2907 corresponding code in background and inserts name of the corresponding
  2908 resulting ML value/function/datatype constructor binding in place.
  2909 All occurrences of @{code} with a single ML block are generated
  2910 simultaneously.  Provides a generic and safe interface for
  2911 instrumentalizing code generation.  See
  2912 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2913 In future you ought to refrain from ad-hoc compiling generated SML
  2914 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2915 cannot refer to constants for which user-defined serializations are
  2916 set.  Refer to the corresponding ML counterpart directly in that
  2917 cases.
  2918 
  2919 * Command 'rep_datatype': instead of theorem names the command now
  2920 takes a list of terms denoting the constructors of the type to be
  2921 represented as datatype.  The characteristic theorems have to be
  2922 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2923 have disappeared in favour of existing ones:
  2924 
  2925     unit_induct                 ~> unit.induct
  2926     prod_induct                 ~> prod.induct
  2927     sum_induct                  ~> sum.induct
  2928     Suc_Suc_eq                  ~> nat.inject
  2929     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2930 
  2931 
  2932 *** HOL-Algebra ***
  2933 
  2934 * New locales for orders and lattices where the equivalence relation
  2935 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2936 locales use a record structure with field eq for the equivalence.
  2937 
  2938 * New theory of factorial domains.
  2939 
  2940 * Units_l_inv and Units_r_inv are now simp rules by default.
  2941 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2942 and/or r_inv will now also require deletion of these lemmas.
  2943 
  2944 * Renamed the following theorems, INCOMPATIBILITY:
  2945 
  2946 UpperD ~> Upper_memD
  2947 LowerD ~> Lower_memD
  2948 least_carrier ~> least_closed
  2949 greatest_carrier ~> greatest_closed
  2950 greatest_Lower_above ~> greatest_Lower_below
  2951 one_zero ~> carrier_one_zero
  2952 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2953 
  2954 
  2955 *** HOL-Nominal ***
  2956 
  2957 * Nominal datatypes can now contain type-variables.
  2958 
  2959 * Commands 'nominal_inductive' and 'equivariance' work with local
  2960 theory targets.
  2961 
  2962 * Nominal primrec can now works with local theory targets and its
  2963 specification syntax now conforms to the general format as seen in
  2964 'inductive' etc.
  2965 
  2966 * Method "perm_simp" honours the standard simplifier attributes
  2967 (no_asm), (no_asm_use) etc.
  2968 
  2969 * The new predicate #* is defined like freshness, except that on the
  2970 left hand side can be a set or list of atoms.
  2971 
  2972 * Experimental command 'nominal_inductive2' derives strong induction
  2973 principles for inductive definitions.  In contrast to
  2974 'nominal_inductive', which can only deal with a fixed number of
  2975 binders, it can deal with arbitrary expressions standing for sets of
  2976 atoms to be avoided.  The only inductive definition we have at the
  2977 moment that needs this generalisation is the typing rule for Lets in
  2978 the algorithm W:
  2979 
  2980  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2981  -----------------------------------------------------------------
  2982          Gamma |- Let x be t1 in t2 : T2
  2983 
  2984 In this rule one wants to avoid all the binders that are introduced by
  2985 "close Gamma T1".  We are looking for other examples where this
  2986 feature might be useful.  Please let us know.
  2987 
  2988 
  2989 *** HOLCF ***
  2990 
  2991 * Reimplemented the simplification procedure for proving continuity
  2992 subgoals.  The new simproc is extensible; users can declare additional
  2993 continuity introduction rules with the attribute [cont2cont].
  2994 
  2995 * The continuity simproc now uses a different introduction rule for
  2996 solving continuity subgoals on terms with lambda abstractions.  In
  2997 some rare cases the new simproc may fail to solve subgoals that the
  2998 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2999 Potential INCOMPATIBILITY.
  3000 
  3001 * Command 'fixrec': specification syntax now conforms to the general
  3002 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3003 examples.  INCOMPATIBILITY.
  3004 
  3005 
  3006 *** ZF ***
  3007 
  3008 * Proof of Zorn's Lemma for partial orders.
  3009 
  3010 
  3011 *** ML ***
  3012 
  3013 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3014 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3015 depends on multithreading, so timouts will not work before Poly/ML
  3016 5.2.1!
  3017 
  3018 * High-level support for concurrent ML programming, see
  3019 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3020 particularly convenient to organize independent functional
  3021 computations.  The concept of "synchronized variables" provides a
  3022 higher-order interface for components with shared state, avoiding the
  3023 delicate details of mutexes and condition variables.  (Requires
  3024 Poly/ML 5.2.1 or later.)
  3025 
  3026 * ML bindings produced via Isar commands are stored within the Isar
  3027 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3028 become thread-safe and work with undo as expected (concerning
  3029 top-level bindings, not side-effects on global references).
  3030 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3031 compiler at runtime; really global bindings need to be given outside a
  3032 theory.  (Requires Poly/ML 5.2 or later.)
  3033 
  3034 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3035 context.  Top-level ML bindings are stored within the proof context in
  3036 a purely sequential fashion, disregarding the nested proof structure.
  3037 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3038 proof.  (Requires Poly/ML 5.2 or later.)
  3039 
  3040 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3041 and Method.setup, as well as Isar commands 'attribute_setup' and
  3042 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3043 existing code accordingly, or use plain 'setup' together with old
  3044 Method.add_method.
  3045 
  3046 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3047 to 'a -> thm, while results are always tagged with an authentic oracle
  3048 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3049 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3050 accordingly.  Note that extra performance may be gained by producing
  3051 the cterm carefully, avoiding slow Thm.cterm_of.
  3052 
  3053 * Simplified interface for defining document antiquotations via
  3054 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3055 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3056 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3057 examples.
  3058 
  3059 * More systematic treatment of long names, abstract name bindings, and
  3060 name space operations.  Basic operations on qualified names have been
  3061 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3062 Long_Name.append.  Old type bstring has been mostly replaced by
  3063 abstract type binding (see structure Binding), which supports precise
  3064 qualification by packages and local theory targets, as well as proper
  3065 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3066 bstring values into Binding.name, or better pass through abstract
  3067 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3068 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3069 
  3070 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3071 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3072 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3073 
  3074 * Disposed old type and term read functions (Sign.read_def_typ,
  3075 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3076 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3077 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3078 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3079 resort for legacy applications.
  3080 
  3081 * Disposed old declarations, tactics, tactic combinators that refer to
  3082 the simpset or claset of an implicit theory (such as Addsimps,
  3083 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3084 embedded ML text, or local_simpset_of with a proper context passed as
  3085 explicit runtime argument.
  3086 
  3087 * Rules and tactics that read instantiations (read_instantiate,
  3088 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3089 context, which is required for parsing and type-checking.  Moreover,
  3090 the variables are specified as plain indexnames, not string encodings
  3091 thereof.  INCOMPATIBILITY.
  3092 
  3093 * Generic Toplevel.add_hook interface allows to analyze the result of
  3094 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3095 for theorem dependency output of transactions resulting in a new
  3096 theory state.
  3097 
  3098 * ML antiquotations: block-structured compilation context indicated by
  3099 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3100 
  3101   @{binding name}                         - basic name binding
  3102   @{let ?pat = term}                      - term abbreviation (HO matching)
  3103   @{note name = fact}                     - fact abbreviation
  3104   @{thm fact}                             - singleton fact (with attributes)
  3105   @{thms fact}                            - general fact (with attributes)
  3106   @{lemma prop by method}                 - singleton goal
  3107   @{lemma prop by meth1 meth2}            - singleton goal
  3108   @{lemma prop1 ... propN by method}      - general goal
  3109   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3110   @{lemma (open) ...}                     - open derivation
  3111 
  3112 
  3113 *** System ***
  3114 
  3115 * The Isabelle "emacs" tool provides a specific interface to invoke
  3116 Proof General / Emacs, with more explicit failure if that is not
  3117 installed (the old isabelle-interface script silently falls back on
  3118 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3119 installation location of the Proof General distribution.
  3120 
  3121 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3122 the Isabelle process into a JVM/Scala application.  See
  3123 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3124 process wrapper has been discontinued.)
  3125 
  3126 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3127 
  3128 * Various status messages (with exact source position information) are
  3129 emitted, if proper markup print mode is enabled.  This allows
  3130 user-interface components to provide detailed feedback on internal
  3131 prover operations.
  3132 
  3133 
  3134 
  3135 New in Isabelle2008 (June 2008)
  3136 -------------------------------
  3137 
  3138 *** General ***
  3139 
  3140 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3141 and updated, with formally checked references as hyperlinks.
  3142 
  3143 * Theory loader: use_thy (and similar operations) no longer set the
  3144 implicit ML context, which was occasionally hard to predict and in
  3145 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3146 provides a proper context already.
  3147 
  3148 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3149 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3150 'use' within a theory file will do the job.
  3151 
  3152 * Name space merge now observes canonical order, i.e. the second space
  3153 is inserted into the first one, while existing entries in the first
  3154 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3155 swap theory imports.
  3156 
  3157 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3158 INCOMPATIBILITY in identifier syntax etc.
  3159 
  3160 * Outer syntax: string tokens no longer admit escaped white space,
  3161 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3162 white space without escapes.
  3163 
  3164 * Outer syntax: string tokens may contain arbitrary character codes
  3165 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3166 "foo_bar".
  3167 
  3168 
  3169 *** Pure ***
  3170 
  3171 * Context-dependent token translations.  Default setup reverts locally
  3172 fixed variables, and adds hilite markup for undeclared frees.
  3173 
  3174 * Unused theorems can be found using the new command 'unused_thms'.
  3175 There are three ways of invoking it:
  3176 
  3177 (1) unused_thms
  3178      Only finds unused theorems in the current theory.
  3179 
  3180 (2) unused_thms thy_1 ... thy_n -
  3181      Finds unused theorems in the current theory and all of its ancestors,
  3182      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3183 
  3184 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3185      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3186      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3187      their ancestors.
  3188 
  3189 In order to increase the readability of the list produced by
  3190 unused_thms, theorems that have been created by a particular instance
  3191 of a theory command such as 'inductive' or 'function' are considered
  3192 to belong to the same "group", meaning that if at least one theorem in
  3193 this group is used, the other theorems in the same group are no longer
  3194 reported as unused.  Moreover, if all theorems in the group are
  3195 unused, only one theorem in the group is displayed.
  3196 
  3197 Note that proof objects have to be switched on in order for
  3198 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3199 usually the case when using Proof General with the default settings).
  3200 
  3201 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3202 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3203 duplicate fact bindings, or even accidental fact duplications.  Note
  3204 that tools may maintain dynamically scoped facts systematically, using
  3205 PureThy.add_thms_dynamic.
  3206 
  3207 * Command 'hide' now allows to hide from "fact" name space as well.
  3208 
  3209 * Eliminated destructive theorem database, simpset, claset, and
  3210 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3211 update of theories within ML code.
  3212 
  3213 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3214 INCOMPATIBILITY, object-logics depending on former Pure require
  3215 additional setup PureThy.old_appl_syntax_setup; object-logics
  3216 depending on former CPure need to refer to Pure.
  3217 
  3218 * Commands 'use' and 'ML' are now purely functional, operating on
  3219 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3220 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3221 INCOMPATIBILITY.
  3222 
  3223 * Command 'setup': discontinued implicit version with ML reference.
  3224 
  3225 * Instantiation target allows for simultaneous specification of class
  3226 instance operations together with an instantiation proof.
  3227 Type-checking phase allows to refer to class operations uniformly.
  3228 See src/HOL/Complex/Complex.thy for an Isar example and
  3229 src/HOL/Library/Eval.thy for an ML example.
  3230 
  3231 * Indexing of literal facts: be more serious about including only
  3232 facts from the visible specification/proof context, but not the
  3233 background context (locale etc.).  Affects `prop` notation and method
  3234 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3235 situations.
  3236 
  3237 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3238 "(open)" option, which used to expose internal bound variables to the
  3239 proof text.
  3240 
  3241 * Isar statements: removed obsolete case "rule_context".
  3242 INCOMPATIBILITY, better use explicit fixes/assumes.
  3243 
  3244 * Locale proofs: default proof step now includes 'unfold_locales';
  3245 hence 'proof' without argument may be used to unfold locale
  3246 predicates.
  3247 
  3248 
  3249 *** Document preparation ***
  3250 
  3251 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3252 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3253 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3254 spot); renamed link color from "darkblue" to "linkcolor" (default
  3255 value unchanged, can be redefined via \definecolor); no longer sets
  3256 "a4paper" option (unnecessary or even intrusive).
  3257 
  3258 * Antiquotation @{lemma A method} proves proposition A by the given
  3259 method (either a method name or a method name plus (optional) method
  3260 arguments in parentheses) and prints A just like @{prop A}.
  3261 
  3262 
  3263 *** HOL ***
  3264 
  3265 * New primrec package.  Specification syntax conforms in style to
  3266 definition/function/....  No separate induction rule is provided.  The
  3267 "primrec" command distinguishes old-style and new-style specifications
  3268 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3269 When adjusting theories, beware: constants stemming from new-style
  3270 primrec specifications have authentic syntax.
  3271 
  3272 * Metis prover is now an order of magnitude faster, and also works
  3273 with multithreading.
  3274 
  3275 * Metis: the maximum number of clauses that can be produced from a
  3276 theorem is now given by the attribute max_clauses.  Theorems that
  3277 exceed this number are ignored, with a warning printed.
  3278 
  3279 * Sledgehammer no longer produces structured proofs by default. To
  3280 enable, declare [[sledgehammer_full = true]].  Attributes
  3281 reconstruction_modulus, reconstruction_sorts renamed
  3282 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3283 
  3284 * Method "induct_scheme" derives user-specified induction rules
  3285 from well-founded induction and completeness of patterns. This factors
  3286 out some operations that are done internally by the function package
  3287 and makes them available separately.  See
  3288 src/HOL/ex/Induction_Scheme.thy for examples.
  3289 
  3290 * More flexible generation of measure functions for termination
  3291 proofs: Measure functions can be declared by proving a rule of the
  3292 form "is_measure f" and giving it the [measure_function] attribute.
  3293 The "is_measure" predicate is logically meaningless (always true), and
  3294 just guides the heuristic.  To find suitable measure functions, the
  3295 termination prover sets up the goal "is_measure ?f" of the appropriate
  3296 type and generates all solutions by prolog-style backwards proof using
  3297 the declared rules.
  3298 
  3299 This setup also deals with rules like 
  3300 
  3301   "is_measure f ==> is_measure (list_size f)"
  3302 
  3303 which accommodates nested datatypes that recurse through lists.
  3304 Similar rules are predeclared for products and option types.
  3305 
  3306 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3307 
  3308   INCOMPATIBILITIES:
  3309 
  3310   - Definitions of overloaded constants on sets have to be replaced by
  3311     definitions on => and bool.
  3312 
  3313   - Some definitions of overloaded operators on sets can now be proved
  3314     using the definitions of the operators on => and bool.  Therefore,
  3315     the following theorems have been renamed:
  3316 
  3317       subset_def   -> subset_eq
  3318       psubset_def  -> psubset_eq
  3319       set_diff_def -> set_diff_eq
  3320       Compl_def    -> Compl_eq
  3321       Sup_set_def  -> Sup_set_eq
  3322       Inf_set_def  -> Inf_set_eq
  3323       sup_set_def  -> sup_set_eq
  3324       inf_set_def  -> inf_set_eq
  3325 
  3326   - Due to the incompleteness of the HO unification algorithm, some
  3327     rules such as subst may require manual instantiation, if some of
  3328     the unknowns in the rule is a set.
  3329 
  3330   - Higher order unification and forward proofs:
  3331     The proof pattern
  3332 
  3333       have "P (S::'a set)" <...>
  3334       then have "EX S. P S" ..
  3335 
  3336     no longer works (due to the incompleteness of the HO unification
  3337     algorithm) and must be replaced by the pattern
  3338 
  3339       have "EX S. P S"
  3340       proof
  3341         show "P S" <...>
  3342       qed
  3343 
  3344   - Calculational reasoning with subst (or similar rules):
  3345     The proof pattern
  3346 
  3347       have "P (S::'a set)" <...>
  3348       also have "S = T" <...>
  3349       finally have "P T" .
  3350 
  3351     no longer works (for similar reasons as the previous example) and
  3352     must be replaced by something like
  3353 
  3354       have "P (S::'a set)" <...>
  3355       moreover have "S = T" <...>
  3356       ultimately have "P T" by simp
  3357 
  3358   - Tactics or packages written in ML code:
  3359     Code performing pattern matching on types via
  3360 
  3361       Type ("set", [T]) => ...
  3362 
  3363     must be rewritten. Moreover, functions like strip_type or
  3364     binder_types no longer return the right value when applied to a
  3365     type of the form
  3366 
  3367       T1 => ... => Tn => U => bool
  3368 
  3369     rather than
  3370 
  3371       T1 => ... => Tn => U set
  3372 
  3373 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3374 Wellfounded_Relations to theory Wellfounded.
  3375 
  3376 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3377 
  3378 * Class finite no longer treats UNIV as class parameter.  Use class
  3379 enum from theory Library/Enum instead to achieve a similar effect.
  3380 INCOMPATIBILITY.
  3381 
  3382 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3383 and "Cons".  INCOMPATIBILITY.
  3384 
  3385 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3386 Potential INCOMPATIBILITY.
  3387 
  3388 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3389 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3390 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3391 
  3392 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3393 the same name in theory Orderings:
  3394 
  3395   less_trans
  3396   less_linear
  3397   le_imp_less_or_eq
  3398   le_less_trans
  3399   less_le_trans
  3400   less_not_sym
  3401   less_asym
  3402 
  3403 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3404 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3405 and different variable names.
  3406 
  3407 * Library/Option_ord.thy: Canonical order on option type.
  3408 
  3409 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3410 finite maps.
  3411 
  3412 * Library/Countable.thy: Type class for countable types.
  3413 
  3414 * Theory Int: The representation of numerals has changed.  The infix
  3415 operator BIT and the bit datatype with constructors B0 and B1 have
  3416 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3417 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3418 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3419 accordingly.
  3420 
  3421 * Theory Nat: definition of <= and < on natural numbers no longer
  3422 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3423 le_def and less_def have disappeared.  Consider lemmas not_less
  3424 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3425 
  3426 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3427 (whose purpose mainly is for various fold_set functionals) have been
  3428 abandoned in favor of the existing algebraic classes
  3429 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3430 lower_semilattice (resp. upper_semilattice) and linorder.
  3431 INCOMPATIBILITY.
  3432 
  3433 * Theory Transitive_Closure: induct and cases rules now declare proper
  3434 case_names ("base" and "step").  INCOMPATIBILITY.
  3435 
  3436 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3437 lattices.  The form set-specific version is available as
  3438 Inductive.lfp_ordinal_induct_set.
  3439 
  3440 * Renamed theorems "power.simps" to "power_int.simps".
  3441 INCOMPATIBILITY.
  3442 
  3443 * Class semiring_div provides basic abstract properties of semirings
  3444 with division and modulo operations.  Subsumes former class dvd_mod.
  3445 
  3446 * Merged theories IntDef, Numeral and IntArith into unified theory
  3447 Int.  INCOMPATIBILITY.
  3448 
  3449 * Theory Library/Code_Index: type "index" now represents natural
  3450 numbers rather than integers.  INCOMPATIBILITY.
  3451 
  3452 * New class "uminus" with operation "uminus" (split of from class
  3453 "minus" which now only has operation "minus", binary).
  3454 INCOMPATIBILITY.
  3455 
  3456 * Constants "card", "internal_split", "option_map" now with authentic
  3457 syntax.  INCOMPATIBILITY.
  3458 
  3459 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3460 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3461 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3462 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3463 Sup_set_def, le_def, less_def, option_map_def now with object
  3464 equality.  INCOMPATIBILITY.
  3465 
  3466 * Records. Removed K_record, and replaced it by pure lambda term
  3467 %x. c. The simplifier setup is now more robust against eta expansion.
  3468 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3469 
  3470 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3471 
  3472 * Library/ListVector: new theory of arithmetic vector operations.
  3473 
  3474 * Library/Order_Relation: new theory of various orderings as sets of
  3475 pairs.  Defines preorders, partial orders, linear orders and
  3476 well-orders on sets and on types.
  3477 
  3478 
  3479 *** ZF ***
  3480 
  3481 * Renamed some theories to allow to loading both ZF and HOL in the
  3482 same session:
  3483 
  3484   Datatype  -> Datatype_ZF
  3485   Inductive -> Inductive_ZF
  3486   Int       -> Int_ZF
  3487   IntDiv    -> IntDiv_ZF
  3488   Nat       -> Nat_ZF
  3489   List      -> List_ZF
  3490   Main      -> Main_ZF
  3491 
  3492 INCOMPATIBILITY: ZF theories that import individual theories below
  3493 Main might need to be adapted.  Regular theory Main is still
  3494 available, as trivial extension of Main_ZF.
  3495 
  3496 
  3497 *** ML ***
  3498 
  3499 * ML within Isar: antiquotation @{const name} or @{const
  3500 name(typargs)} produces statically-checked Const term.
  3501 
  3502 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3503 (of the same name).  Removed obsolete print command.
  3504 
  3505 * Removed obsolete "use_legacy_bindings" function.
  3506 
  3507 * The ``print mode'' is now a thread-local value derived from a global
  3508 template (the former print_mode reference), thus access becomes
  3509 non-critical.  The global print_mode reference is for session
  3510 management only; user-code should use print_mode_value,
  3511 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3512 
  3513 * Functions system/system_out provide a robust way to invoke external
  3514 shell commands, with propagation of interrupts (requires Poly/ML
  3515 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3516 
  3517 
  3518 *** System ***
  3519 
  3520 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3521 in accordance with Proof General 3.7, which prefers GNU emacs.
  3522 
  3523 * isatool tty runs Isabelle process with plain tty interaction;
  3524 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3525 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3526 
  3527 * isatool browser now works with Cygwin as well, using general
  3528 "javapath" function defined in Isabelle process environment.
  3529 
  3530 * YXML notation provides a simple and efficient alternative to
  3531 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3532 isatool yxml as described in the Isabelle system manual.
  3533 
  3534 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3535 provides general wrapper for managing an Isabelle process in a robust
  3536 fashion, with ``cooked'' output from stdin/stderr.
  3537 
  3538 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3539 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3540 
  3541 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3542 way of changing the user's settings is via
  3543 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3544 script.
  3545 
  3546 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3547 cores of the underlying machine, which is a good starting point for
  3548 optimal performance tuning.  The corresponding usedir option -M allows
  3549 "max" as an alias for "0".  WARNING: does not work on certain versions
  3550 of Mac OS (with Poly/ML 5.1).
  3551 
  3552 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3553 adverse effect of Isabelle flooding interactive front-ends (notably
  3554 ProofGeneral / XEmacs).
  3555 
  3556 
  3557 
  3558 New in Isabelle2007 (November 2007)
  3559 -----------------------------------
  3560 
  3561 *** General ***
  3562 
  3563 * More uniform information about legacy features, notably a
  3564 warning/error of "Legacy feature: ...", depending on the state of the
  3565 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3566 legacy features will disappear eventually.
  3567 
  3568 * Theory syntax: the header format ``theory A = B + C:'' has been
  3569 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3570 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3571 
  3572 * Theory syntax: the old non-Isar theory file format has been
  3573 discontinued altogether.  Note that ML proof scripts may still be used
  3574 with Isar theories; migration is usually quite simple with the ML
  3575 function use_legacy_bindings.  INCOMPATIBILITY.
  3576 
  3577 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3578 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3579 quotes.
  3580 
  3581 * Theory loader: be more serious about observing the static theory
  3582 header specifications (including optional directories), but not the
  3583 accidental file locations of previously successful loads.  The strict
  3584 update policy of former update_thy is now already performed by
  3585 use_thy, so the former has been removed; use_thys updates several
  3586 theories simultaneously, just as 'imports' within a theory header
  3587 specification, but without merging the results.  Potential
  3588 INCOMPATIBILITY: may need to refine theory headers and commands
  3589 ROOT.ML which depend on load order.
  3590 
  3591 * Theory loader: optional support for content-based file
  3592 identification, instead of the traditional scheme of full physical
  3593 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3594 (cf. the system manual).  The new scheme allows to work with
  3595 non-finished theories in persistent session images, such that source
  3596 files may be moved later on without requiring reloads.
  3597 
  3598 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3599 file (with the same base name as the theory) are considered a legacy
  3600 feature, which will disappear eventually. Even now, the theory loader
  3601 no longer maintains dependencies on such files.
  3602 
  3603 * Syntax: the scope for resolving ambiguities via type-inference is
  3604 now limited to individual terms, instead of whole simultaneous
  3605 specifications as before. This greatly reduces the complexity of the
  3606 syntax module and improves flexibility by separating parsing and
  3607 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3608 'fixes' etc.) are required in rare situations.
  3609 
  3610 * Syntax: constants introduced by new-style packages ('definition',
  3611 'abbreviation' etc.) are passed through the syntax module in
  3612 ``authentic mode''. This means that associated mixfix annotations
  3613 really stick to such constants, independently of potential name space
  3614 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3615 trees are represented slightly differently, may need to adapt syntax
  3616 translations accordingly. Use CONST marker in 'translations' and
  3617 @{const_syntax} antiquotation in 'parse_translation' etc.
  3618 
  3619 * Legacy goal package: reduced interface to the bare minimum required
  3620 to keep existing proof scripts running.  Most other user-level
  3621 functions are now part of the OldGoals structure, which is *not* open
  3622 by default (consider isatool expandshort before open OldGoals).
  3623 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3624 these tend to cause confusion about the actual goal (!) context being
  3625 used here, which is not necessarily the same as the_context().
  3626 
  3627 * Command 'find_theorems': supports "*" wild-card in "name:"
  3628 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3629 support a specific search form (see ProofGeneral/CHANGES).
  3630 
  3631 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3632 by default, which means that "prems" (and also "fixed variables") are
  3633 suppressed from proof state output.  Note that the ProofGeneral
  3634 settings mechanism allows to change and save options persistently, but
  3635 older versions of Isabelle will fail to start up if a negative prems
  3636 limit is imposed.
  3637 
  3638 * Local theory targets may be specified by non-nested blocks of
  3639 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3640 contain definitions, theorems etc., including any derived mechanism
  3641 that has been implemented on top of these primitives.  This concept
  3642 generalizes the existing ``theorem (in ...)'' towards more versatility
  3643 and scalability.
  3644 
  3645 * Proof General interface: proper undo of final 'end' command;
  3646 discontinued Isabelle/classic mode (ML proof scripts).
  3647 
  3648 
  3649 *** Document preparation ***
  3650 
  3651 * Added antiquotation @{theory name} which prints the given name,
  3652 after checking that it refers to a valid ancestor theory in the
  3653 current context.
  3654 
  3655 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3656 check the given source text as ML type/structure, printing verbatim.
  3657 
  3658 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3659 "c args == rhs" given in the current context.  (Any number of
  3660 arguments may be given on the LHS.)
  3661 
  3662 
  3663 *** Pure ***
  3664 
  3665 * The 'class' package offers a combination of axclass and locale to
  3666 achieve Haskell-like type classes in Isabelle.  Definitions and
  3667 theorems within a class context produce both relative results (with
  3668 implicit parameters according to the locale context), and polymorphic
  3669 constants with qualified polymorphism (according to the class
  3670 context).  Within the body context of a 'class' target, a separate
  3671 syntax layer ("user space type system") takes care of converting
  3672 between global polymorphic consts and internal locale representation.
  3673 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3674 "isatool doc classes" provides a tutorial.
  3675 
  3676 * Generic code generator framework allows to generate executable
  3677 code for ML and Haskell (including Isabelle classes).  A short usage
  3678 sketch:
  3679 
  3680     internal compilation:
  3681         export_code <list of constants (term syntax)> in SML
  3682     writing SML code to a file:
  3683         export_code <list of constants (term syntax)> in SML <filename>
  3684     writing OCaml code to a file:
  3685         export_code <list of constants (term syntax)> in OCaml <filename>
  3686     writing Haskell code to a bunch of files:
  3687         export_code <list of constants (term syntax)> in Haskell <filename>
  3688 
  3689     evaluating closed propositions to True/False using code generation:
  3690         method ``eval''
  3691 
  3692 Reasonable default setup of framework in HOL.
  3693 
  3694 Theorem attributs for selecting and transforming function equations theorems:
  3695 
  3696     [code fun]:        select a theorem as function equation for a specific constant
  3697     [code fun del]:    deselect a theorem as function equation for a specific constant
  3698     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3699     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3700 
  3701 User-defined serializations (target in {SML, OCaml, Haskell}):
  3702 
  3703     code_const <and-list of constants (term syntax)>
  3704       {(target) <and-list of const target syntax>}+
  3705 
  3706     code_type <and-list of type constructors>
  3707       {(target) <and-list of type target syntax>}+
  3708 
  3709     code_instance <and-list of instances>
  3710       {(target)}+
  3711         where instance ::= <type constructor> :: <class>
  3712 
  3713     code_class <and_list of classes>
  3714       {(target) <and-list of class target syntax>}+
  3715         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3716 
  3717 code_instance and code_class only are effective to target Haskell.
  3718 
  3719 For example usage see src/HOL/ex/Codegenerator.thy and
  3720 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3721 generation from Isabelle/HOL theories is available via "isatool doc
  3722 codegen".
  3723 
  3724 * Code generator: consts in 'consts_code' Isar commands are now
  3725 referred to by usual term syntax (including optional type
  3726 annotations).
  3727 
  3728 * Command 'no_translations' removes translation rules from theory
  3729 syntax.
  3730 
  3731 * Overloaded definitions are now actually checked for acyclic
  3732 dependencies.  The overloading scheme is slightly more general than
  3733 that of Haskell98, although Isabelle does not demand an exact
  3734 correspondence to type class and instance declarations.
  3735 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3736 exotic versions of overloading -- at the discretion of the user!
  3737 
  3738 Polymorphic constants are represented via type arguments, i.e. the
  3739 instantiation that matches an instance against the most general
  3740 declaration given in the signature.  For example, with the declaration
  3741 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3742 as c(nat).  Overloading is essentially simultaneous structural
  3743 recursion over such type arguments.  Incomplete specification patterns
  3744 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3745 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3746 Command 'print_theory' outputs the normalized system of recursive
  3747 equations, see section "definitions".
  3748 
  3749 * Configuration options are maintained within the theory or proof
  3750 context (with name and type bool/int/string), providing a very simple
  3751 interface to a poor-man's version of general context data.  Tools may
  3752 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3753 these values using Config.get etc.  Users may change options via an
  3754 associated attribute of the same name.  This form of context
  3755 declaration works particularly well with commands 'declare' or
  3756 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3757 very easy to avoid global references, which would not observe Isar
  3758 toplevel undo/redo and fail to work with multithreading.
  3759 
  3760 Various global ML references of Pure and HOL have been turned into
  3761 configuration options:
  3762 
  3763   Unify.search_bound		unify_search_bound
  3764   Unify.trace_bound		unify_trace_bound
  3765   Unify.trace_simp		unify_trace_simp
  3766   Unify.trace_types		unify_trace_types
  3767   Simplifier.simp_depth_limit	simp_depth_limit
  3768   Blast.depth_limit		blast_depth_limit
  3769   DatatypeProp.dtK		datatype_distinctness_limit
  3770   fast_arith_neq_limit  	fast_arith_neq_limit
  3771   fast_arith_split_limit	fast_arith_split_limit
  3772 
  3773 * Named collections of theorems may be easily installed as context
  3774 data using the functor NamedThmsFun (see also
  3775 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3776 attributes; there is also a toplevel print command.  This facility is
  3777 just a common case of general context data, which is the preferred way
  3778 for anything more complex than just a list of facts in canonical
  3779 order.
  3780 
  3781 * Isar: command 'declaration' augments a local theory by generic
  3782 declaration functions written in ML.  This enables arbitrary content
  3783 being added to the context, depending on a morphism that tells the
  3784 difference of the original declaration context wrt. the application
  3785 context encountered later on.
  3786 
  3787 * Isar: proper interfaces for simplification procedures.  Command
  3788 'simproc_setup' declares named simprocs (with match patterns, and body
  3789 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3790 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3791 
  3792 * Isar: an extra pair of brackets around attribute declarations
  3793 abbreviates a theorem reference involving an internal dummy fact,
  3794 which will be ignored later --- only the effect of the attribute on
  3795 the background context will persist.  This form of in-place
  3796 declarations is particularly useful with commands like 'declare' and
  3797 'using', for example ``have A using [[simproc a]] by simp''.
  3798 
  3799 * Isar: method "assumption" (and implicit closing of subproofs) now
  3800 takes simple non-atomic goal assumptions into account: after applying
  3801 an assumption as a rule the resulting subgoals are solved by atomic
  3802 assumption steps.  This is particularly useful to finish 'obtain'
  3803 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3804 without referring to the original premise "!!x. P x ==> thesis" in the
  3805 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3806 more permissive.
  3807 
  3808 * Isar: implicit use of prems from the Isar proof context is
  3809 considered a legacy feature.  Common applications like ``have A .''
  3810 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3811 referencing facts explicitly here improves readability and
  3812 maintainability of proof texts.
  3813 
  3814 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3815 the obtained context from the course of reasoning!  For example:
  3816 
  3817   assume "EX x y. A x & B y"   -- "any previous fact"
  3818   then guess x and y by clarify
  3819 
  3820 This technique is potentially adventurous, depending on the facts and
  3821 proof tools being involved here.
  3822 
  3823 * Isar: known facts from the proof context may be specified as literal
  3824 propositions, using ASCII back-quote syntax.  This works wherever
  3825 named facts used to be allowed so far, in proof commands, proof
  3826 methods, attributes etc.  Literal facts are retrieved from the context
  3827 according to unification of type and term parameters.  For example,
  3828 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3829 theorems in the current context, then these are valid literal facts:
  3830 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3831 
  3832 There is also a proof method "fact" which does the same composition
  3833 for explicit goal states, e.g. the following proof texts coincide with
  3834 certain special cases of literal facts:
  3835 
  3836   have "A" by fact                 ==  note `A`
  3837   have "A ==> B" by fact           ==  note `A ==> B`
  3838   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3839   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3840 
  3841 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3842 outer syntax.  Thus symbolic identifiers may be used without
  3843 additional white space in declarations like this: ``assume *: A''.
  3844 
  3845 * Isar: 'print_facts' prints all local facts of the current context,
  3846 both named and unnamed ones.
  3847 
  3848 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3849 
  3850   def x == "t" and y == "u"
  3851 
  3852 * Isar: added command 'unfolding', which is structurally similar to
  3853 'using', but affects both the goal state and facts by unfolding given
  3854 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3855 'unfolded' attribute may be replaced by first-class proof text.
  3856 
  3857 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3858 and command 'unfolding' now all support object-level equalities
  3859 (potentially conditional).  The underlying notion of rewrite rule is
  3860 analogous to the 'rule_format' attribute, but *not* that of the
  3861 Simplifier (which is usually more generous).
  3862 
  3863 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3864 premises of a theorem by n. Useful in conjunction with drule.
  3865 
  3866 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3867 method expression within a sandbox consisting of the first N
  3868 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3869 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3870 simplifies all new goals that emerge from applying rule foo to the
  3871 originally first one.
  3872 
  3873 * Isar: schematic goals are no longer restricted to higher-order
  3874 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3875 expected.
  3876 
  3877 * Isar: the conclusion of a long theorem statement is now either
  3878 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3879 (essentially a disjunction of cases with local parameters and
  3880 assumptions).  The latter allows to express general elimination rules
  3881 adequately; in this notation common elimination rules look like this:
  3882 
  3883   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3884     assumes "EX x. P x"
  3885     obtains x where "P x"
  3886 
  3887   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3888     assumes "A & B"
  3889     obtains A and B
  3890 
  3891   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3892     assumes "A | B"
  3893     obtains
  3894       A
  3895     | B
  3896 
  3897 The subsequent classical rules even refer to the formal "thesis"
  3898 explicitly:
  3899 
  3900   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3901     obtains "~ thesis"
  3902 
  3903   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3904     obtains "thesis ==> something"
  3905 
  3906 The actual proof of an 'obtains' statement is analogous to that of the
  3907 Isar proof element 'obtain', only that there may be several cases.
  3908 Optional case names may be specified in parentheses; these will be
  3909 available both in the present proof and as annotations in the
  3910 resulting rule, for later use with the 'cases' method (cf. attribute
  3911 case_names).
  3912 
  3913 * Isar: the assumptions of a long theorem statement are available as
  3914 "assms" fact in the proof context.  This is more appropriate than the
  3915 (historical) "prems", which refers to all assumptions of the current
  3916 context, including those from the target locale, proof body etc.
  3917 
  3918 * Isar: 'print_statement' prints theorems from the current theory or
  3919 proof context in long statement form, according to the syntax of a
  3920 top-level lemma.
  3921 
  3922 * Isar: 'obtain' takes an optional case name for the local context
  3923 introduction rule (default "that").
  3924 
  3925 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3926 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3927 to occur.
  3928 
  3929 * Pure: syntax "CONST name" produces a fully internalized constant
  3930 according to the current context.  This is particularly useful for
  3931 syntax translations that should refer to internal constant
  3932 representations independently of name spaces.
  3933 
  3934 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3935 instead of "FOO ". This allows multiple binder declarations to coexist
  3936 in the same context.  INCOMPATIBILITY.
  3937 
  3938 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3939 primitive that also works in a locale context (both for constants and
  3940 fixed variables). Type declaration and internal syntactic representation
  3941 of given constants retrieved from the context. Likewise, the
  3942 'no_notation' command allows to remove given syntax annotations from the
  3943 current context.
  3944 
  3945 * Isar/locales: new derived specification elements 'axiomatization',
  3946 'definition', 'abbreviation', which support type-inference, admit
  3947 object-level specifications (equality, equivalence).  See also the
  3948 isar-ref manual.  Examples:
  3949 
  3950   axiomatization
  3951     eq  (infix "===" 50) where
  3952     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3953 
  3954   definition "f x y = x + y + 1"
  3955   definition g where "g x = f x x"
  3956 
  3957   abbreviation
  3958     neq  (infix "=!=" 50) where
  3959     "x =!= y == ~ (x === y)"
  3960 
  3961 These specifications may be also used in a locale context.  Then the
  3962 constants being introduced depend on certain fixed parameters, and the
  3963 constant name is qualified by the locale base name.  An internal
  3964 abbreviation takes care for convenient input and output, making the
  3965 parameters implicit and using the original short name.  See also
  3966 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3967 entities from a monomorphic theory.
  3968 
  3969 Presently, abbreviations are only available 'in' a target locale, but
  3970 not inherited by general import expressions.  Also note that
  3971 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3972 'translations' in common applications.  The "no_abbrevs" print mode
  3973 prevents folding of abbreviations in term output.
  3974 
  3975 Concrete syntax is attached to specified constants in internal form,
  3976 independently of name spaces.  The parse tree representation is
  3977 slightly different -- use 'notation' instead of raw 'syntax', and
  3978 'translations' with explicit "CONST" markup to accommodate this.
  3979 
  3980 * Pure/Isar: unified syntax for new-style specification mechanisms
  3981 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3982 full type inference and dummy patterns ("_").  For example:
  3983 
  3984   definition "K x _ = x"
  3985 
  3986   inductive conj for A B
  3987   where "A ==> B ==> conj A B"
  3988 
  3989 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3990 the current context.  Print mode "no_abbrevs" prevents inversion of
  3991 abbreviations on output.
  3992 
  3993 * Isar/locales: improved parameter handling: use of locales "var" and
  3994 "struct" no longer necessary; - parameter renamings are no longer
  3995 required to be injective.  For example, this allows to define
  3996 endomorphisms as locale endom = homom mult mult h.
  3997 
  3998 * Isar/locales: changed the way locales with predicates are defined.
  3999 Instead of accumulating the specification, the imported expression is
  4000 now an interpretation.  INCOMPATIBILITY: different normal form of
  4001 locale expressions.  In particular, in interpretations of locales with
  4002 predicates, goals repesenting already interpreted fragments are not
  4003 removed automatically.  Use methods `intro_locales' and
  4004 `unfold_locales'; see below.
  4005 
  4006 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4007 provide backward reasoning on locales predicates.  The methods are
  4008 aware of interpretations and discharge corresponding goals.
  4009 `intro_locales' is less aggressive then `unfold_locales' and does not
  4010 unfold predicates to assumptions.
  4011 
  4012 * Isar/locales: the order in which locale fragments are accumulated
  4013 has changed.  This enables to override declarations from fragments due
  4014 to interpretations -- for example, unwanted simp rules.
  4015 
  4016 * Isar/locales: interpretation in theories and proof contexts has been
  4017 extended.  One may now specify (and prove) equations, which are
  4018 unfolded in interpreted theorems.  This is useful for replacing
  4019 defined concepts (constants depending on locale parameters) by
  4020 concepts already existing in the target context.  Example:
  4021 
  4022   interpretation partial_order ["op <= :: [int, int] => bool"]
  4023     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4024 
  4025 Typically, the constant `partial_order.less' is created by a
  4026 definition specification element in the context of locale
  4027 partial_order.
  4028 
  4029 * Method "induct": improved internal context management to support
  4030 local fixes and defines on-the-fly. Thus explicit meta-level
  4031 connectives !!  and ==> are rarely required anymore in inductive goals
  4032 (using object-logic connectives for this purpose has been long
  4033 obsolete anyway). Common proof patterns are explained in
  4034 src/HOL/Induct/Common_Patterns.thy, see also
  4035 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4036 examples.
  4037 
  4038 * Method "induct": improved handling of simultaneous goals. Instead of
  4039 introducing object-level conjunction, the statement is now split into
  4040 several conclusions, while the corresponding symbolic cases are nested
  4041 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4042 see src/HOL/Induct/Common_Patterns.thy, for example.
  4043 
  4044 * Method "induct": mutual induction rules are now specified as a list
  4045 of rule sharing the same induction cases. HOL packages usually provide
  4046 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4047 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4048 mutual induction rules differently, i.e. like this:
  4049 
  4050   (induct rule: foo_bar.inducts)
  4051   (induct set: foo bar)
  4052   (induct pred: foo bar)
  4053   (induct type: foo bar)
  4054 
  4055 The ML function ProjectRule.projections turns old-style rules into the
  4056 new format.
  4057 
  4058 * Method "coinduct": dual of induction, see
  4059 src/HOL/Library/Coinductive_List.thy for various examples.
  4060 
  4061 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4062 considered a legacy feature.
  4063 
  4064 * Attribute "symmetric" produces result with standardized schematic
  4065 variables (index 0).  Potential INCOMPATIBILITY.
  4066 
  4067 * Simplifier: by default the simplifier trace only shows top level
  4068 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4069 default. Thus there is less danger of being flooded by the trace. The
  4070 trace indicates where parts have been suppressed.
  4071   
  4072 * Provers/classical: removed obsolete classical version of elim_format
  4073 attribute; classical elim/dest rules are now treated uniformly when
  4074 manipulating the claset.
  4075 
  4076 * Provers/classical: stricter checks to ensure that supplied intro,
  4077 dest and elim rules are well-formed; dest and elim rules must have at
  4078 least one premise.
  4079 
  4080 * Provers/classical: attributes dest/elim/intro take an optional
  4081 weight argument for the rule (just as the Pure versions).  Weights are
  4082 ignored by automated tools, but determine the search order of single
  4083 rule steps.
  4084 
  4085 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4086 where the body does not mention the bound variable.  Note that dummy
  4087 patterns implicitly depend on their context of bounds, which makes
  4088 "{_. _}" match any set comprehension as expected.  Potential
  4089 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4090 constant "_idtdummy" in the binding position.
  4091 
  4092 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4093 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4094 for example "A -> B" => "Pi A (%_. B)".
  4095 
  4096 * Pure: 'class_deps' command visualizes the subclass relation, using
  4097 the graph browser tool.
  4098 
  4099 * Pure: 'print_theory' now suppresses certain internal declarations by
  4100 default; use '!' option for full details.
  4101 
  4102 
  4103 *** HOL ***
  4104 
  4105 * Method "metis" proves goals by applying the Metis general-purpose
  4106 resolution prover (see also http://gilith.com/software/metis/).
  4107 Examples are in the directory MetisExamples.  WARNING: the
  4108 Isabelle/HOL-Metis integration does not yet work properly with
  4109 multi-threading.
  4110   
  4111 * Command 'sledgehammer' invokes external automatic theorem provers as
  4112 background processes.  It generates calls to the "metis" method if
  4113 successful. These can be pasted into the proof.  Users do not have to
  4114 wait for the automatic provers to return.  WARNING: does not really
  4115 work with multi-threading.
  4116 
  4117 * New "auto_quickcheck" feature tests outermost goal statements for
  4118 potential counter-examples.  Controlled by ML references
  4119 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4120 5000 milliseconds).  Fails silently if statements is outside of
  4121 executable fragment, or any other codgenerator problem occurs.
  4122 
  4123 * New constant "undefined" with axiom "undefined x = undefined".
  4124 
  4125 * Added class "HOL.eq", allowing for code generation with polymorphic
  4126 equality.
  4127 
  4128 * Some renaming of class constants due to canonical name prefixing in
  4129 the new 'class' package:
  4130 
  4131     HOL.abs ~> HOL.abs_class.abs
  4132     HOL.divide ~> HOL.divide_class.divide
  4133     0 ~> HOL.zero_class.zero
  4134     1 ~> HOL.one_class.one
  4135     op + ~> HOL.plus_class.plus
  4136     op - ~> HOL.minus_class.minus
  4137     uminus ~> HOL.minus_class.uminus
  4138     op * ~> HOL.times_class.times
  4139     op < ~> HOL.ord_class.less
  4140     op <= > HOL.ord_class.less_eq
  4141     Nat.power ~> Power.power_class.power
  4142     Nat.size ~> Nat.size_class.size
  4143     Numeral.number_of ~> Numeral.number_class.number_of
  4144     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4145     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4146     Orderings.min ~> Orderings.ord_class.min
  4147     Orderings.max ~> Orderings.ord_class.max
  4148     Divides.op div ~> Divides.div_class.div
  4149     Divides.op mod ~> Divides.div_class.mod
  4150     Divides.op dvd ~> Divides.div_class.dvd
  4151 
  4152 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4153 
  4154 a) User-defined constants using any of the names "plus", "minus",
  4155 "times", "less" or "less_eq". The standard syntax translations for
  4156 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4157 names.
  4158 
  4159 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4160 INCOMPATIBILITY: use more specific names.
  4161 
  4162 c) Permutative equations (e.g. "a + b = b + a")
  4163 Since the change of names also changes the order of terms, permutative
  4164 rewrite rules may get applied in a different order. Experience shows
  4165 that this is rarely the case (only two adaptions in the whole Isabelle
  4166 distribution).  INCOMPATIBILITY: rewrite proofs
  4167 
  4168 d) ML code directly refering to constant names
  4169 This in general only affects hand-written proof tactics, simprocs and
  4170 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4171 Consider using @{const_name} antiquotation.
  4172 
  4173 * New class "default" with associated constant "default".
  4174 
  4175 * Function "sgn" is now overloaded and available on int, real, complex
  4176 (and other numeric types), using class "sgn".  Two possible defs of
  4177 sgn are given as equational assumptions in the classes sgn_if and
  4178 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4179 INCOMPATIBILITY.
  4180 
  4181 * Locale "partial_order" now unified with class "order" (cf. theory
  4182 Orderings), added parameter "less".  INCOMPATIBILITY.
  4183 
  4184 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4185 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4186 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4187 
  4188 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4189 changed order of proof goals in instance proofs.
  4190 
  4191 * The transitivity reasoner for partial and linear orders is set up
  4192 for classes "order" and "linorder".  Instances of the reasoner are available
  4193 in all contexts importing or interpreting the corresponding locales.
  4194 Method "order" invokes the reasoner separately; the reasoner
  4195 is also integrated with the Simplifier as a solver.  Diagnostic
  4196 command 'print_orders' shows the available instances of the reasoner
  4197 in the current context.
  4198 
  4199 * Localized monotonicity predicate in theory "Orderings"; integrated
  4200 lemmas max_of_mono and min_of_mono with this predicate.
  4201 INCOMPATIBILITY.
  4202 
  4203 * Formulation of theorem "dense" changed slightly due to integration
  4204 with new class dense_linear_order.
  4205 
  4206 * Uniform lattice theory development in HOL.
  4207 
  4208     constants "meet" and "join" now named "inf" and "sup"
  4209     constant "Meet" now named "Inf"
  4210 
  4211     classes "meet_semilorder" and "join_semilorder" now named
  4212       "lower_semilattice" and "upper_semilattice"
  4213     class "lorder" now named "lattice"
  4214     class "comp_lat" now named "complete_lattice"
  4215 
  4216     Instantiation of lattice classes allows explicit definitions
  4217     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4218 
  4219   INCOMPATIBILITY.  Theorem renames:
  4220 
  4221     meet_left_le            ~> inf_le1
  4222     meet_right_le           ~> inf_le2
  4223     join_left_le            ~> sup_ge1
  4224     join_right_le           ~> sup_ge2
  4225     meet_join_le            ~> inf_sup_ord
  4226     le_meetI                ~> le_infI
  4227     join_leI                ~> le_supI
  4228     le_meet                 ~> le_inf_iff
  4229     le_join                 ~> ge_sup_conv
  4230     meet_idempotent         ~> inf_idem
  4231     join_idempotent         ~> sup_idem
  4232     meet_comm               ~> inf_commute
  4233     join_comm               ~> sup_commute
  4234     meet_leI1               ~> le_infI1
  4235     meet_leI2               ~> le_infI2
  4236     le_joinI1               ~> le_supI1
  4237     le_joinI2               ~> le_supI2
  4238     meet_assoc              ~> inf_assoc
  4239     join_assoc              ~> sup_assoc
  4240     meet_left_comm          ~> inf_left_commute
  4241     meet_left_idempotent    ~> inf_left_idem
  4242     join_left_comm          ~> sup_left_commute
  4243     join_left_idempotent    ~> sup_left_idem
  4244     meet_aci                ~> inf_aci
  4245     join_aci                ~> sup_aci
  4246     le_def_meet             ~> le_iff_inf
  4247     le_def_join             ~> le_iff_sup
  4248     join_absorp2            ~> sup_absorb2
  4249     join_absorp1            ~> sup_absorb1
  4250     meet_absorp1            ~> inf_absorb1
  4251     meet_absorp2            ~> inf_absorb2
  4252     meet_join_absorp        ~> inf_sup_absorb
  4253     join_meet_absorp        ~> sup_inf_absorb
  4254     distrib_join_le         ~> distrib_sup_le
  4255     distrib_meet_le         ~> distrib_inf_le
  4256 
  4257     add_meet_distrib_left   ~> add_inf_distrib_left
  4258     add_join_distrib_left   ~> add_sup_distrib_left
  4259     is_join_neg_meet        ~> is_join_neg_inf
  4260     is_meet_neg_join        ~> is_meet_neg_sup
  4261     add_meet_distrib_right  ~> add_inf_distrib_right
  4262     add_join_distrib_right  ~> add_sup_distrib_right
  4263     add_meet_join_distribs  ~> add_sup_inf_distribs
  4264     join_eq_neg_meet        ~> sup_eq_neg_inf
  4265     meet_eq_neg_join        ~> inf_eq_neg_sup
  4266     add_eq_meet_join        ~> add_eq_inf_sup
  4267     meet_0_imp_0            ~> inf_0_imp_0
  4268     join_0_imp_0            ~> sup_0_imp_0
  4269     meet_0_eq_0             ~> inf_0_eq_0
  4270     join_0_eq_0             ~> sup_0_eq_0
  4271     neg_meet_eq_join        ~> neg_inf_eq_sup
  4272     neg_join_eq_meet        ~> neg_sup_eq_inf
  4273     join_eq_if              ~> sup_eq_if
  4274 
  4275     mono_meet               ~> mono_inf
  4276     mono_join               ~> mono_sup
  4277     meet_bool_eq            ~> inf_bool_eq
  4278     join_bool_eq            ~> sup_bool_eq
  4279     meet_fun_eq             ~> inf_fun_eq
  4280     join_fun_eq             ~> sup_fun_eq
  4281     meet_set_eq             ~> inf_set_eq
  4282     join_set_eq             ~> sup_set_eq
  4283     meet1_iff               ~> inf1_iff
  4284     meet2_iff               ~> inf2_iff
  4285     meet1I                  ~> inf1I
  4286     meet2I                  ~> inf2I
  4287     meet1D1                 ~> inf1D1
  4288     meet2D1                 ~> inf2D1
  4289     meet1D2                 ~> inf1D2
  4290     meet2D2                 ~> inf2D2
  4291     meet1E                  ~> inf1E
  4292     meet2E                  ~> inf2E
  4293     join1_iff               ~> sup1_iff
  4294     join2_iff               ~> sup2_iff
  4295     join1I1                 ~> sup1I1
  4296     join2I1                 ~> sup2I1
  4297     join1I1                 ~> sup1I1
  4298     join2I2                 ~> sup1I2
  4299     join1CI                 ~> sup1CI
  4300     join2CI                 ~> sup2CI
  4301     join1E                  ~> sup1E
  4302     join2E                  ~> sup2E
  4303 
  4304     is_meet_Meet            ~> is_meet_Inf
  4305     Meet_bool_def           ~> Inf_bool_def
  4306     Meet_fun_def            ~> Inf_fun_def
  4307     Meet_greatest           ~> Inf_greatest
  4308     Meet_lower              ~> Inf_lower
  4309     Meet_set_def            ~> Inf_set_def
  4310 
  4311     Sup_def                 ~> Sup_Inf
  4312     Sup_bool_eq             ~> Sup_bool_def
  4313     Sup_fun_eq              ~> Sup_fun_def
  4314     Sup_set_eq              ~> Sup_set_def
  4315 
  4316     listsp_meetI            ~> listsp_infI
  4317     listsp_meet_eq          ~> listsp_inf_eq
  4318 
  4319     meet_min                ~> inf_min
  4320     join_max                ~> sup_max
  4321 
  4322 * Added syntactic class "size"; overloaded constant "size" now has
  4323 type "'a::size ==> bool"
  4324 
  4325 * Internal reorganisation of `size' of datatypes: size theorems
  4326 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4327 simplification rules by default!); theorems "prod.size" now named
  4328 "*.size".
  4329 
  4330 * Class "div" now inherits from class "times" rather than "type".
  4331 INCOMPATIBILITY.
  4332 
  4333 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4334 Linorder etc.  have disappeared; operations defined in terms of
  4335 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4336 
  4337 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4338 
  4339 * HOL-Word: New extensive library and type for generic, fixed size
  4340 machine words, with arithemtic, bit-wise, shifting and rotating
  4341 operations, reflection into int, nat, and bool lists, automation for
  4342 linear arithmetic (by automatic reflection into nat or int), including
  4343 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4344 arithmetic type classes, supporting automatic simplification of
  4345 numerals on all operations.
  4346 
  4347 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4348 
  4349 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4350 
  4351 * Code generator library theories:
  4352   - Code_Integer represents HOL integers by big integer literals in target
  4353     languages.
  4354   - Code_Char represents HOL characters by character literals in target
  4355     languages.
  4356   - Code_Char_chr like Code_Char, but also offers treatment of character
  4357     codes; includes Code_Integer.
  4358   - Executable_Set allows to generate code for finite sets using lists.
  4359   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4360     denominator).
  4361   - Executable_Real implements a subset of real numbers, namly those
  4362     representable by rational numbers.
  4363   - Efficient_Nat implements natural numbers by integers, which in general will
  4364     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4365     includes Code_Integer.
  4366   - Code_Index provides an additional datatype index which is mapped to
  4367     target-language built-in integers.
  4368   - Code_Message provides an additional datatype message_string which is isomorphic to
  4369     strings; messages are mapped to target-language strings.
  4370 
  4371 * New package for inductive predicates
  4372 
  4373   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4374 
  4375     inductive
  4376       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4377       for z_1 :: U_1 and ... and z_n :: U_m
  4378     where
  4379       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4380     | ...
  4381 
  4382   with full support for type-inference, rather than
  4383 
  4384     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4385 
  4386     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4387     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4388 
  4389     inductive "s z_1 ... z_m"
  4390     intros
  4391       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4392       ...
  4393 
  4394   For backward compatibility, there is a wrapper allowing inductive
  4395   sets to be defined with the new package via
  4396 
  4397     inductive_set
  4398       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4399       for z_1 :: U_1 and ... and z_n :: U_m
  4400     where
  4401       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4402     | ...
  4403 
  4404   or
  4405 
  4406     inductive_set
  4407       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4408       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4409       for z_1 :: U_1 and ... and z_n :: U_m
  4410     where
  4411       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4412     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4413     | ...
  4414 
  4415   if the additional syntax "p ..." is required.
  4416 
  4417   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4418   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4419 
  4420   INCOMPATIBILITIES:
  4421 
  4422   - Since declaration and definition of inductive sets or predicates
  4423     is no longer separated, abbreviations involving the newly
  4424     introduced sets or predicates must be specified together with the
  4425     introduction rules after the 'where' keyword (see above), rather
  4426     than before the actual inductive definition.
  4427 
  4428   - The variables in induction and elimination rules are now
  4429     quantified in the order of their occurrence in the introduction
  4430     rules, rather than in alphabetical order. Since this may break
  4431     some proofs, these proofs either have to be repaired, e.g. by
  4432     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4433     statements of the form
  4434 
  4435       case (rule_i a_i_1 ... a_i_{k_i})
  4436 
  4437     or the old order of quantification has to be restored by explicitly adding
  4438     meta-level quantifiers in the introduction rules, i.e.
  4439 
  4440       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4441 
  4442   - The format of the elimination rules is now
  4443 
  4444       p z_1 ... z_m x_1 ... x_n ==>
  4445         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4446         ==> ... ==> P
  4447 
  4448     for predicates and
  4449 
  4450       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4451         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4452         ==> ... ==> P
  4453 
  4454     for sets rather than
  4455 
  4456       x : s z_1 ... z_m ==>
  4457         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4458         ==> ... ==> P
  4459 
  4460     This may require terms in goals to be expanded to n-tuples
  4461     (e.g. using case_tac or simplification with the split_paired_all
  4462     rule) before the above elimination rule is applicable.
  4463 
  4464   - The elimination or case analysis rules for (mutually) inductive
  4465     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4466     list of rules "p_1_..._p_k.elims" is no longer available.
  4467 
  4468 * New package "function"/"fun" for general recursive functions,
  4469 supporting mutual and nested recursion, definitions in local contexts,
  4470 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4471 for small examples, and the separate tutorial on the function
  4472 package. The old recdef "package" is still available as before, but
  4473 users are encouraged to use the new package.
  4474 
  4475 * Method "lexicographic_order" automatically synthesizes termination
  4476 relations as lexicographic combinations of size measures. 
  4477 
  4478 * Case-expressions allow arbitrary constructor-patterns (including
  4479 "_") and take their order into account, like in functional
  4480 programming.  Internally, this is translated into nested
  4481 case-expressions; missing cases are added and mapped to the predefined
  4482 constant "undefined". In complicated cases printing may no longer show
  4483 the original input but the internal form. Lambda-abstractions allow
  4484 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4485 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4486 variable.
  4487 
  4488 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4489 is an abbreviation for "of_nat :: nat => int". The simplification
  4490 rules for "of_nat" have been changed to work like "int" did
  4491 previously.  Potential INCOMPATIBILITY:
  4492   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4493   - of_nat_diff and of_nat_mult are no longer default simp rules
  4494 
  4495 * Method "algebra" solves polynomial equations over (semi)rings using
  4496 Groebner bases. The (semi)ring structure is defined by locales and the
  4497 tool setup depends on that generic context. Installing the method for
  4498 a specific type involves instantiating the locale and possibly adding
  4499 declarations for computation on the coefficients.  The method is
  4500 already instantiated for natural numbers and for the axiomatic class
  4501 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4502 CALCULEMUS 2007 for the general principles underlying this
  4503 architecture of context-aware proof-tools.
  4504 
  4505 * Method "ferrack" implements quantifier elimination over
  4506 special-purpose dense linear orders using locales (analogous to
  4507 "algebra"). The method is already installed for class
  4508 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4509 rat, etc.
  4510 
  4511 * Former constant "List.op @" now named "List.append".  Use ML
  4512 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4513 circumvent possible incompatibilities when working on ML level.
  4514 
  4515 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4516 
  4517 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4518 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4519 
  4520 * New syntax for Haskell-like list comprehension (input only), eg.
  4521 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4522 
  4523 * The special syntax for function "filter" has changed from [x :
  4524 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4525 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4526 
  4527 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4528 defined on nat only, as an abbreviation for [a..<Suc b]
  4529 INCOMPATIBILITY.
  4530 
  4531 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4532 
  4533 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4534 
  4535 * New lemma collection field_simps (an extension of ring_simps) for
  4536 manipulating (in)equations involving division. Multiplies with all
  4537 denominators that can be proved to be non-zero (in equations) or
  4538 positive/negative (in inequations).
  4539 
  4540 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4541 have been improved and renamed to ring_simps, group_simps and
  4542 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4543 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4544 
  4545 * Theory Library/Commutative_Ring: switched from recdef to function
  4546 package; constants add, mul, pow now curried.  Infix syntax for
  4547 algebraic operations.
  4548 
  4549 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4550 INCOMPATIBILITY.
  4551 
  4552 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4553 INCOMPATIBILITY.
  4554 
  4555 * HOL/records: generalised field-update to take a function on the
  4556 field rather than the new value: r(|A := x|) is translated to A_update
  4557 (K x) r The K-combinator that is internally used is called K_record.
  4558 INCOMPATIBILITY: Usage of the plain update functions has to be
  4559 adapted.
  4560  
  4561 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4562 * x = 0, which are required for a semiring.  Richer structures do not
  4563 inherit from semiring_0 anymore, because this property is a theorem
  4564 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4565 there is more to prove, but this is mostly trivial.
  4566 
  4567 * Class "recpower" is generalized to arbitrary monoids, not just
  4568 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4569 commutativity or semiring properties additionally.
  4570 
  4571 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4572 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4573 better use 'abbreviation'.
  4574 
  4575 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4576 
  4577 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4578 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4579 significant changes for setting up numeral syntax for types:
  4580   - New constants Numeral.pred and Numeral.succ instead
  4581       of former Numeral.bin_pred and Numeral.bin_succ.
  4582   - Use integer operations instead of bin_add, bin_mult and so on.
  4583   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4584   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4585 
  4586 See src/HOL/Integ/IntArith.thy for an example setup.
  4587 
  4588 * Command 'normal_form' computes the normal form of a term that may
  4589 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4590 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4591 heavy-duty computations because the functions are compiled to ML
  4592 first.  Correspondingly, a method "normalization" is provided.  See
  4593 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4594 
  4595 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4596 25 like -->); output depends on the "iff" print_mode, the default is
  4597 "A = B" (with priority 50).
  4598 
  4599 * Relations less (<) and less_eq (<=) are also available on type bool.
  4600 Modified syntax to disallow nesting without explicit parentheses,
  4601 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4602 INCOMPATIBILITY.
  4603 
  4604 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4605 
  4606 * Relation composition operator "op O" now has precedence 75 and binds
  4607 stronger than union and intersection. INCOMPATIBILITY.
  4608 
  4609 * The old set interval syntax "{m..n(}" (and relatives) has been
  4610 removed.  Use "{m..<n}" (and relatives) instead.
  4611 
  4612 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4613 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4614 ``declare [[simproc del: neq]]''.
  4615 
  4616 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4617 True/False.
  4618 
  4619 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4620 
  4621 * Theorem setsum_mult renamed to setsum_right_distrib.
  4622 
  4623 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4624 ``rule'' method.
  4625 
  4626 * Reimplemented methods "sat" and "satx", with several improvements:
  4627 goals no longer need to be stated as "<prems> ==> False", equivalences
  4628 (i.e. "=" on type bool) are handled, variable names of the form
  4629 "lit_<n>" are no longer reserved, significant speedup.
  4630 
  4631 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4632 zChaff is still supported as well.
  4633 
  4634 * 'inductive' and 'datatype': provide projections of mutual rules,
  4635 bundled as foo_bar.inducts;
  4636 
  4637 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4638 Library.
  4639 
  4640 * Library: moved theory Accessible_Part to main HOL.
  4641 
  4642 * Library: added theory Coinductive_List of potentially infinite lists
  4643 as greatest fixed-point.
  4644 
  4645 * Library: added theory AssocList which implements (finite) maps as
  4646 association lists.
  4647 
  4648 * Method "evaluation" solves goals (i.e. a boolean expression)
  4649 efficiently by compiling it to ML.  The goal is "proved" (via an
  4650 oracle) if it evaluates to True.
  4651 
  4652 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4653 also when invoked by the simplifier.  This results in the Simplifier
  4654 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4655 Configuration option fast_arith_split_limit=0 recovers the old
  4656 behavior.
  4657 
  4658 * Support for hex (0x20) and binary (0b1001) numerals.
  4659 
  4660 * New method: reify eqs (t), where eqs are equations for an
  4661 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4662 parameter, computes a term s::'b and a list xs::'a list and proves the
  4663 theorem I xs s = t. This is also known as reification or quoting. The
  4664 resulting theorem is applied to the subgoal to substitute t with I xs
  4665 s.  If t is omitted, the subgoal itself is reified.
  4666 
  4667 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4668 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4669 where f is supposed to be a computable function (in the sense of code
  4670 generattion). The method uses reify to compute s and xs as above then
  4671 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4672 r and finally gets the theorem t = r, which is again applied to the
  4673 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4674 
  4675 * Reflection: Automatic reification now handels binding, an example is
  4676 available in src/HOL/ex/ReflectionEx.thy
  4677 
  4678 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4679 command 'statespace' that is similar to 'record', but introduces an
  4680 abstract specification based on the locale infrastructure instead of
  4681 HOL types.  This leads to extra flexibility in composing state spaces,
  4682 in particular multiple inheritance and renaming of components.
  4683 
  4684 
  4685 *** HOL-Complex ***
  4686 
  4687 * Hyperreal: Functions root and sqrt are now defined on negative real
  4688 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4689 Nonnegativity side conditions have been removed from many lemmas, so
  4690 that more subgoals may now be solved by simplification; potential
  4691 INCOMPATIBILITY.
  4692 
  4693 * Real: new type classes formalize real normed vector spaces and
  4694 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4695 and norm :: 'a => real.
  4696 
  4697 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4698 reals into other types. The overloaded constant Reals :: 'a set is now
  4699 defined as range of_real; potential INCOMPATIBILITY.
  4700 
  4701 * Real: proper support for ML code generation, including 'quickcheck'.
  4702 Reals are implemented as arbitrary precision rationals.
  4703 
  4704 * Hyperreal: Several constants that previously worked only for the
  4705 reals have been generalized, so they now work over arbitrary vector
  4706 spaces. Type annotations may need to be added in some cases; potential
  4707 INCOMPATIBILITY.
  4708 
  4709   Infinitesimal  :: ('a::real_normed_vector) star set
  4710   HFinite        :: ('a::real_normed_vector) star set
  4711   HInfinite      :: ('a::real_normed_vector) star set
  4712   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4713   monad          :: ('a::real_normed_vector) star => 'a star set
  4714   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4715   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4716   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4717   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4718   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4719   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4720   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4721   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4722   sgn            :: 'a::real_normed_vector => 'a
  4723   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4724 
  4725 * Complex: Some complex-specific constants are now abbreviations for
  4726 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4727 hnorm.  Other constants have been entirely removed in favor of the
  4728 polymorphic versions (INCOMPATIBILITY):
  4729 
  4730   approx        <-- capprox
  4731   HFinite       <-- CFinite
  4732   HInfinite     <-- CInfinite
  4733   Infinitesimal <-- CInfinitesimal
  4734   monad         <-- cmonad
  4735   galaxy        <-- cgalaxy
  4736   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4737   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4738   (ns)deriv     <-- (ns)cderiv
  4739 
  4740 
  4741 *** HOL-Algebra ***
  4742 
  4743 * Formalisation of ideals and the quotient construction over rings.
  4744 
  4745 * Order and lattice theory no longer based on records.
  4746 INCOMPATIBILITY.
  4747 
  4748 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4749 greatest_closed.  INCOMPATIBILITY.
  4750 
  4751 * Method algebra is now set up via an attribute.  For examples see
  4752 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4753 of algebraic structures.
  4754 
  4755 * Renamed theory CRing to Ring.
  4756 
  4757 
  4758 *** HOL-Nominal ***
  4759 
  4760 * Substantial, yet incomplete support for nominal datatypes (binding
  4761 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4762 src/HOL/Nominal/Examples.  Prospective users should consult
  4763 http://isabelle.in.tum.de/nominal/
  4764 
  4765 
  4766 *** ML ***
  4767 
  4768 * ML basics: just one true type int, which coincides with IntInf.int
  4769 (even on SML/NJ).
  4770 
  4771 * ML within Isar: antiquotations allow to embed statically-checked
  4772 formal entities in the source, referring to the context available at
  4773 compile-time.  For example:
  4774 
  4775 ML {* @{sort "{zero,one}"} *}
  4776 ML {* @{typ "'a => 'b"} *}
  4777 ML {* @{term "%x. x"} *}
  4778 ML {* @{prop "x == y"} *}
  4779 ML {* @{ctyp "'a => 'b"} *}
  4780 ML {* @{cterm "%x. x"} *}
  4781 ML {* @{cprop "x == y"} *}
  4782 ML {* @{thm asm_rl} *}
  4783 ML {* @{thms asm_rl} *}
  4784 ML {* @{type_name c} *}
  4785 ML {* @{type_syntax c} *}
  4786 ML {* @{const_name c} *}
  4787 ML {* @{const_syntax c} *}
  4788 ML {* @{context} *}
  4789 ML {* @{theory} *}
  4790 ML {* @{theory Pure} *}
  4791 ML {* @{theory_ref} *}
  4792 ML {* @{theory_ref Pure} *}
  4793 ML {* @{simpset} *}
  4794 ML {* @{claset} *}
  4795 ML {* @{clasimpset} *}
  4796 
  4797 The same works for sources being ``used'' within an Isar context.
  4798 
  4799 * ML in Isar: improved error reporting; extra verbosity with
  4800 ML_Context.trace enabled.
  4801 
  4802 * Pure/General/table.ML: the join operations now works via exceptions
  4803 DUP/SAME instead of type option. This is simpler in simple cases, and
  4804 admits slightly more efficient complex applications.
  4805 
  4806 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4807 use Context.generic instead of just theory.
  4808 
  4809 * Pure: datatype Context.generic joins theory/Proof.context and
  4810 provides some facilities for code that works in either kind of
  4811 context, notably GenericDataFun for uniform theory and proof data.
  4812 
  4813 * Pure: simplified internal attribute type, which is now always
  4814 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4815 local (Proof.context) attributes have been discontinued, while
  4816 minimizing code duplication. Thm.rule_attribute and
  4817 Thm.declaration_attribute build canonical attributes; see also structure
  4818 Context for further operations on Context.generic, notably
  4819 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4820 declarations and definitions.
  4821 
  4822 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4823 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4824 init only required for impure data. INCOMPATIBILITY: empty really need
  4825 to be empty (no dependencies on theory content!)
  4826 
  4827 * Pure/kernel: consts certification ignores sort constraints given in
  4828 signature declarations. (This information is not relevant to the
  4829 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4830 potential INCOMPATIBILITY.
  4831 
  4832 * Pure: axiomatic type classes are now purely definitional, with
  4833 explicit proofs of class axioms and super class relations performed
  4834 internally. See Pure/axclass.ML for the main internal interfaces --
  4835 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4836 AxClass.axiomatize_class/classrel/arity supersede
  4837 Sign.add_classes/classrel/arities.
  4838 
  4839 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4840 global/local versions on theory vs. Proof.context have been
  4841 discontinued; Attrib.syntax and Method.syntax have been adapted
  4842 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4843 attributes, methods, etc.
  4844 
  4845 * Pure: several functions of signature "... -> theory -> theory * ..."
  4846 have been reoriented to "... -> theory -> ... * theory" in order to
  4847 allow natural usage in combination with the ||>, ||>>, |-> and
  4848 fold_map combinators.
  4849 
  4850 * Pure: official theorem names (closed derivations) and additional
  4851 comments (tags) are now strictly separate.  Name hints -- which are
  4852 maintained as tags -- may be attached any time without affecting the
  4853 derivation.
  4854 
  4855 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4856 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4857 achieve the old behaviour.
  4858 
  4859 * Pure: the "Goal" constant is now called "prop", supporting a
  4860 slightly more general idea of ``protecting'' meta-level rule
  4861 statements.
  4862 
  4863 * Pure: Logic.(un)varify only works in a global context, which is now
  4864 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4865 Logic.legacy_(un)varify as temporary workaround.
  4866 
  4867 * Pure: structure Name provides scalable operations for generating
  4868 internal variable names, notably Name.variants etc.  This replaces
  4869 some popular functions from term.ML:
  4870 
  4871   Term.variant		->  Name.variant
  4872   Term.variantlist	->  Name.variant_list
  4873   Term.invent_names	->  Name.invent_list
  4874 
  4875 Note that low-level renaming rarely occurs in new code -- operations
  4876 from structure Variable are used instead (see below).
  4877 
  4878 * Pure: structure Variable provides fundamental operations for proper
  4879 treatment of fixed/schematic variables in a context.  For example,
  4880 Variable.import introduces fixes for schematics of given facts and
  4881 Variable.export reverses the effect (up to renaming) -- this replaces
  4882 various freeze_thaw operations.
  4883 
  4884 * Pure: structure Goal provides simple interfaces for
  4885 init/conclude/finish and tactical prove operations (replacing former
  4886 Tactic.prove).  Goal.prove is the canonical way to prove results
  4887 within a given context; Goal.prove_global is a degraded version for
  4888 theory level goals, including a global Drule.standard.  Note that
  4889 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4890 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4891 in a locale context).
  4892 
  4893 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4894 and type checking (Syntax.check_term etc.), with common combinations
  4895 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4896 which are considered legacy and await removal.
  4897 
  4898 * Pure/Syntax: generic interfaces for type unchecking
  4899 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4900 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4901 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4902 available for convenience, but refer to the very same operations using
  4903 a mere theory instead of a full context.
  4904 
  4905 * Isar: simplified treatment of user-level errors, using exception
  4906 ERROR of string uniformly.  Function error now merely raises ERROR,
  4907 without any side effect on output channels.  The Isar toplevel takes
  4908 care of proper display of ERROR exceptions.  ML code may use plain
  4909 handle/can/try; cat_error may be used to concatenate errors like this:
  4910 
  4911   ... handle ERROR msg => cat_error msg "..."
  4912 
  4913 Toplevel ML code (run directly or through the Isar toplevel) may be
  4914 embedded into the Isar toplevel with exception display/debug like
  4915 this:
  4916 
  4917   Isar.toplevel (fn () => ...)
  4918 
  4919 INCOMPATIBILITY, removed special transform_error facilities, removed
  4920 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4921 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4922 -- use plain ERROR instead.
  4923 
  4924 * Isar: theory setup now has type (theory -> theory), instead of a
  4925 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4926 
  4927 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4928 ProofContext.debug/verbose flags.
  4929 
  4930 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4931 theory before entering a proof state.  Transactions now always see a
  4932 quasi-functional intermediate checkpoint, both in interactive and
  4933 batch mode.
  4934 
  4935 * Isar: simplified interfaces for outer syntax.  Renamed
  4936 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4937 OuterSyntax.add_parsers -- this functionality is now included in
  4938 OuterSyntax.command etc.  INCOMPATIBILITY.
  4939 
  4940 * Simplifier: the simpset of a running simplification process now
  4941 contains a proof context (cf. Simplifier.the_context), which is the
  4942 very context that the initial simpset has been retrieved from (by
  4943 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4944 (solver, looper etc.) may depend on arbitrary proof data.
  4945 
  4946 * Simplifier.inherit_context inherits the proof context (plus the
  4947 local bounds) of the current simplification process; any simproc
  4948 etc. that calls the Simplifier recursively should do this!  Removed
  4949 former Simplifier.inherit_bounds, which is already included here --
  4950 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4951 specify an explicit context using Simplifier.context/theory_context.
  4952 
  4953 * Simplifier/Classical Reasoner: more abstract interfaces
  4954 change_simpset/claset for modifying the simpset/claset reference of a
  4955 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4956 INCOMPATIBILITY.
  4957 
  4958 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4959 "Trueprop" etc.
  4960 
  4961 
  4962 *** System ***
  4963 
  4964 * settings: the default heap location within ISABELLE_HOME_USER now
  4965 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4966 Isabelle installations.
  4967 
  4968 * isabelle-process: option -S (secure mode) disables some critical
  4969 operations, notably runtime compilation and evaluation of ML source
  4970 code.
  4971 
  4972 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4973 
  4974 * Support for parallel execution, using native multicore support of
  4975 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4976 independent theories, according to the given theory header
  4977 specifications. The maximum number of worker threads is specified via
  4978 usedir option -M or the "max-threads" setting in Proof General. A
  4979 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4980 to 6 on a 8-core machine.  User-code needs to observe certain
  4981 guidelines for thread-safe programming, see appendix A in the Isar
  4982 Implementation manual.
  4983 
  4984 
  4985 
  4986 New in Isabelle2005 (October 2005)
  4987 ----------------------------------
  4988 
  4989 *** General ***
  4990 
  4991 * Theory headers: the new header syntax for Isar theories is
  4992 
  4993   theory <name>
  4994   imports <theory1> ... <theoryN>
  4995   uses <file1> ... <fileM>
  4996   begin
  4997 
  4998 where the 'uses' part is optional.  The previous syntax
  4999 
  5000   theory <name> = <theory1> + ... + <theoryN>:
  5001 
  5002 will disappear in the next release.  Use isatool fixheaders to convert
  5003 existing theory files.  Note that there is no change in ancient
  5004 non-Isar theories now, but these will disappear soon.
  5005 
  5006 * Theory loader: parent theories can now also be referred to via
  5007 relative and absolute paths.
  5008 
  5009 * Command 'find_theorems' searches for a list of criteria instead of a
  5010 list of constants. Known criteria are: intro, elim, dest, name:string,
  5011 simp:term, and any term. Criteria can be preceded by '-' to select
  5012 theorems that do not match. Intro, elim, dest select theorems that
  5013 match the current goal, name:s selects theorems whose fully qualified
  5014 name contain s, and simp:term selects all simplification rules whose
  5015 lhs match term.  Any other term is interpreted as pattern and selects
  5016 all theorems matching the pattern. Available in ProofGeneral under
  5017 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5018 
  5019   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5020 
  5021 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5022 matching the current goal as introduction rule and not having "HOL."
  5023 in their name (i.e. not being defined in theory HOL).
  5024 
  5025 * Command 'thms_containing' has been discontinued in favour of
  5026 'find_theorems'; INCOMPATIBILITY.
  5027 
  5028 * Communication with Proof General is now 8bit clean, which means that
  5029 Unicode text in UTF-8 encoding may be used within theory texts (both
  5030 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5031 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5032 
  5033   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5034   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5035 
  5036 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5037 Classical Reasoner.  Typical big applications run around 2 times
  5038 faster.
  5039 
  5040 
  5041 *** Document preparation ***
  5042 
  5043 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5044 of raw sources.  Only those symbols that do not require additional
  5045 LaTeX packages (depending on comments in isabellesym.sty) are
  5046 displayed properly, everything else is left verbatim.  isatool display
  5047 and isatool print are used as front ends (these are subject to the
  5048 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5049 
  5050 * Command tags control specific markup of certain regions of text,
  5051 notably folding and hiding.  Predefined tags include "theory" (for
  5052 theory begin and end), "proof" for proof commands, and "ML" for
  5053 commands involving ML code; the additional tags "visible" and
  5054 "invisible" are unused by default.  Users may give explicit tag
  5055 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5056 interpretation of tags is determined by the LaTeX job during document
  5057 preparation: see option -V of isatool usedir, or options -n and -t of
  5058 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5059 \isadroptag.
  5060 
  5061 Several document versions may be produced at the same time via isatool
  5062 usedir (the generated index.html will link all of them).  Typical
  5063 specifications include ''-V document=theory,proof,ML'' to present
  5064 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5065 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5066 these parts without any formal replacement text.  The Isabelle site
  5067 default settings produce ''document'' and ''outline'' versions as
  5068 specified above.
  5069 
  5070 * Several new antiquotations:
  5071 
  5072   @{term_type term} prints a term with its type annotated;
  5073 
  5074   @{typeof term} prints the type of a term;
  5075 
  5076   @{const const} is the same as @{term const}, but checks that the
  5077   argument is a known logical constant;
  5078 
  5079   @{term_style style term} and @{thm_style style thm} print a term or
  5080   theorem applying a "style" to it
  5081 
  5082   @{ML text}
  5083 
  5084 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5085 definitions, equations, inequations etc., 'concl' printing only the
  5086 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5087 to print the specified premise.  TermStyle.add_style provides an ML
  5088 interface for introducing further styles.  See also the "LaTeX Sugar"
  5089 document practical applications.  The ML antiquotation prints
  5090 type-checked ML expressions verbatim.
  5091 
  5092 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5093 and 'text' support optional locale specification '(in loc)', which
  5094 specifies the default context for interpreting antiquotations.  For
  5095 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5096 
  5097 * Option 'locale=NAME' of antiquotations specifies an alternative
  5098 context interpreting the subsequent argument.  For example: @{thm
  5099 [locale=lattice] inf_assoc}.
  5100 
  5101 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5102 a proof context.
  5103 
  5104 * Proper output of antiquotations for theory commands involving a
  5105 proof context (such as 'locale' or 'theorem (in loc) ...').
  5106 
  5107 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5108 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5109 
  5110 * isatool usedir: new option -C (default true) controls whether option
  5111 -D should include a copy of the original document directory; -C false
  5112 prevents unwanted effects such as copying of administrative CVS data.
  5113 
  5114 
  5115 *** Pure ***
  5116 
  5117 * Considerably improved version of 'constdefs' command.  Now performs
  5118 automatic type-inference of declared constants; additional support for
  5119 local structure declarations (cf. locales and HOL records), see also
  5120 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5121 sequential dependencies of definitions within a single 'constdefs'
  5122 section; moreover, the declared name needs to be an identifier.  If
  5123 all fails, consider to fall back on 'consts' and 'defs' separately.
  5124 
  5125 * Improved indexed syntax and implicit structures.  First of all,
  5126 indexed syntax provides a notational device for subscripted
  5127 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5128 expressions.  Secondly, in a local context with structure
  5129 declarations, number indexes \<^sub>n or the empty index (default
  5130 number 1) refer to a certain fixed variable implicitly; option
  5131 show_structs controls printing of implicit structures.  Typical
  5132 applications of these concepts involve record types and locales.
  5133 
  5134 * New command 'no_syntax' removes grammar declarations (and
  5135 translations) resulting from the given syntax specification, which is
  5136 interpreted in the same manner as for the 'syntax' command.
  5137 
  5138 * 'Advanced' translation functions (parse_translation etc.) may depend
  5139 on the signature of the theory context being presently used for
  5140 parsing/printing, see also isar-ref manual.
  5141 
  5142 * Improved 'oracle' command provides a type-safe interface to turn an
  5143 ML expression of type theory -> T -> term into a primitive rule of
  5144 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5145 is already included here); see also FOL/ex/IffExample.thy;
  5146 INCOMPATIBILITY.
  5147 
  5148 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5149 before); "cI" is no longer bound, use "c.intro" instead.
  5150 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5151 axclasses vs. locales.
  5152 
  5153 * Improved internal renaming of symbolic identifiers -- attach primes
  5154 instead of base 26 numbers.
  5155 
  5156 * New flag show_question_marks controls printing of leading question
  5157 marks in schematic variable names.
  5158 
  5159 * In schematic variable names, *any* symbol following \<^isub> or
  5160 \<^isup> is now treated as part of the base name.  For example, the
  5161 following works without printing of awkward ".0" indexes:
  5162 
  5163   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5164     by simp
  5165 
  5166 * Inner syntax includes (*(*nested*) comments*).
  5167 
  5168 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5169 annotations as "(00...)".
  5170 
  5171 * Clear separation of logical types and nonterminals, where the latter
  5172 may only occur in 'syntax' specifications or type abbreviations.
  5173 Before that distinction was only partially implemented via type class
  5174 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5175 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5176 exotic syntax specifications may require further adaption
  5177 (e.g. Cube/Cube.thy).
  5178 
  5179 * Removed obsolete type class "logic", use the top sort {} instead.
  5180 Note that non-logical types should be declared as 'nonterminals'
  5181 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5182 specifications.
  5183 
  5184 * Attributes 'induct' and 'cases': type or set names may now be
  5185 locally fixed variables as well.
  5186 
  5187 * Simplifier: can now control the depth to which conditional rewriting
  5188 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5189 Limit.
  5190 
  5191 * Simplifier: simplification procedures may now take the current
  5192 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5193 interface), which is very useful for calling the Simplifier
  5194 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5195 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5196 low-level mk_simproc no longer applies Logic.varify internally, to
  5197 allow for use in a context of fixed variables.
  5198 
  5199 * thin_tac now works even if the assumption being deleted contains !!
  5200 or ==>.  More generally, erule now works even if the major premise of
  5201 the elimination rule contains !! or ==>.
  5202 
  5203 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5204 
  5205 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5206 from Pure, which contains all common declarations already.  Both
  5207 theories are defined via plain Isabelle/Isar .thy files.
  5208 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5209 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5210 use isatool fixcpure to adapt your theory and ML sources.
  5211 
  5212 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5213 selections of theorems in named facts via index ranges.
  5214 
  5215 * 'print_theorems': in theory mode, really print the difference
  5216 wrt. the last state (works for interactive theory development only),
  5217 in proof mode print all local facts (cf. 'print_facts');
  5218 
  5219 * 'hide': option '(open)' hides only base names.
  5220 
  5221 * More efficient treatment of intermediate checkpoints in interactive
  5222 theory development.
  5223 
  5224 * Code generator is now invoked via code_module (incremental code
  5225 generation) and code_library (modular code generation, ML structures
  5226 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5227 must be quoted when used as identifiers.
  5228 
  5229 * New 'value' command for reading, evaluating and printing terms using
  5230 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5231 quoted when used as identifier.
  5232 
  5233 
  5234 *** Locales ***
  5235 
  5236 * New commands for the interpretation of locale expressions in
  5237 theories (1), locales (2) and proof contexts (3).  These generate
  5238 proof obligations from the expression specification.  After the
  5239 obligations have been discharged, theorems of the expression are added
  5240 to the theory, target locale or proof context.  The synopsis of the
  5241 commands is a follows:
  5242 
  5243   (1) interpretation expr inst
  5244   (2) interpretation target < expr
  5245   (3) interpret expr inst
  5246 
  5247 Interpretation in theories and proof contexts require a parameter
  5248 instantiation of terms from the current context.  This is applied to
  5249 specifications and theorems of the interpreted expression.
  5250 Interpretation in locales only permits parameter renaming through the
  5251 locale expression.  Interpretation is smart in that interpretations
  5252 that are active already do not occur in proof obligations, neither are
  5253 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5254 inspect active interpretations of a particular locale.  For details,
  5255 see the Isar Reference manual.  Examples can be found in
  5256 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5257 
  5258 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5259 'interpret' instead.
  5260 
  5261 * New context element 'constrains' for adding type constraints to
  5262 parameters.
  5263 
  5264 * Context expressions: renaming of parameters with syntax
  5265 redeclaration.
  5266 
  5267 * Locale declaration: 'includes' disallowed.
  5268 
  5269 * Proper static binding of attribute syntax -- i.e. types / terms /
  5270 facts mentioned as arguments are always those of the locale definition
  5271 context, independently of the context of later invocations.  Moreover,
  5272 locale operations (renaming and type / term instantiation) are applied
  5273 to attribute arguments as expected.
  5274 
  5275 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5276 actual attributes; rare situations may require Attrib.attribute to
  5277 embed those attributes into Attrib.src that lack concrete syntax.
  5278 Attribute implementations need to cooperate properly with the static
  5279 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5280 Attrib.XXX_thm etc. already do the right thing without further
  5281 intervention.  Only unusual applications -- such as "where" or "of"
  5282 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5283 on the context and the facts involved -- may have to assign parsed
  5284 values to argument tokens explicitly.
  5285 
  5286 * Changed parameter management in theorem generation for long goal
  5287 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5288 theorem statement in rare situations.
  5289 
  5290 * Locale inspection command 'print_locale' omits notes elements.  Use
  5291 'print_locale!' to have them included in the output.
  5292 
  5293 
  5294 *** Provers ***
  5295 
  5296 * Provers/hypsubst.ML: improved version of the subst method, for
  5297 single-step rewriting: it now works in bound variable contexts. New is
  5298 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5299 rewrite a different subterm than the original subst method, which is
  5300 still available as 'simplesubst'.
  5301 
  5302 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5303 and quasi orders.
  5304 
  5305 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5306 reflexive-transitive closure of relations.
  5307 
  5308 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5309 limit (previously hard-coded with a value of 20) user-definable.
  5310 
  5311 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5312 is peformed already.  Object-logics merely need to finish their
  5313 initial simpset configuration as before.  INCOMPATIBILITY.
  5314 
  5315 
  5316 *** HOL ***
  5317 
  5318 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5319 
  5320   syntax (epsilon)
  5321     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5322 
  5323 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5324 and x-symbol; use option '-m epsilon' to get it actually printed.
  5325 Moreover, the mathematically important symbolic identifier \<epsilon>
  5326 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5327 
  5328 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5329 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5330 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5331 support corresponding Isar calculations.
  5332 
  5333 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5334 instead of ":".
  5335 
  5336 * theory SetInterval: changed the syntax for open intervals:
  5337 
  5338   Old       New
  5339   {..n(}    {..<n}
  5340   {)n..}    {n<..}
  5341   {m..n(}   {m..<n}
  5342   {)m..n}   {m<..n}
  5343   {)m..n(}  {m<..<n}
  5344 
  5345 The old syntax is still supported but will disappear in the next
  5346 release.  For conversion use the following Emacs search and replace
  5347 patterns (these are not perfect but work quite well):
  5348 
  5349   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5350   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5351 
  5352 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5353 equalities in commutative rings; method 'algebra' provides a generic
  5354 interface.
  5355 
  5356 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5357 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5358 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5359 be a tuple pattern.
  5360 
  5361 Some new syntax forms are available:
  5362 
  5363   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5364   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5365   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5366   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5367 
  5368 The latter form "\<Sum>x < k. e" used to be based on a separate
  5369 function "Summation", which has been discontinued.
  5370 
  5371 * theory Finite_Set: in structured induction proofs, the insert case
  5372 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5373 (insert F x)'.
  5374 
  5375 * The 'refute' command has been extended to support a much larger
  5376 fragment of HOL, including axiomatic type classes, constdefs and
  5377 typedefs, inductive datatypes and recursion.
  5378 
  5379 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5380 Requires zChaff with proof generation to be installed.  See
  5381 HOL/ex/SAT_Examples.thy for examples.
  5382 
  5383 * Datatype induction via method 'induct' now preserves the name of the
  5384 induction variable. For example, when proving P(xs::'a list) by
  5385 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5386 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5387 in unstructured proof scripts.
  5388 
  5389 * Reworked implementation of records.  Improved scalability for
  5390 records with many fields, avoiding performance problems for type
  5391 inference. Records are no longer composed of nested field types, but
  5392 of nested extension types. Therefore the record type only grows linear
  5393 in the number of extensions and not in the number of fields.  The
  5394 top-level (users) view on records is preserved.  Potential
  5395 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5396 old record representation. The type generated for a record is called
  5397 <record_name>_ext_type.
  5398 
  5399 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5400 proofs triggered by a record definition or a simproc (if
  5401 quick_and_dirty is enabled).  Definitions of large records can take
  5402 quite long.
  5403 
  5404 New simproc record_upd_simproc for simplification of multiple record
  5405 updates enabled by default.  Moreover, trivial updates are also
  5406 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5407 occasionally, since simplification is more powerful by default.
  5408 
  5409 * typedef: proper support for polymorphic sets, which contain extra
  5410 type-variables in the term.
  5411 
  5412 * Simplifier: automatically reasons about transitivity chains
  5413 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5414 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5415 old proofs break occasionally as simplification may now solve more
  5416 goals than previously.
  5417 
  5418 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5419 present.  Works for all partial orders (class "order"), in particular
  5420 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5421 just like y <= x.
  5422 
  5423 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5424 bound variable or a constant then the let is unfolded.  Otherwise
  5425 first a is simplified to b, and then f b is simplified to g. If
  5426 possible we abstract b from g arriving at "let x = b in h x",
  5427 otherwise we unfold the let and arrive at g.  The simproc can be
  5428 enabled/disabled by the reference use_let_simproc.  Potential
  5429 INCOMPATIBILITY since simplification is more powerful by default.
  5430 
  5431 * Classical reasoning: the meson method now accepts theorems as arguments.
  5432 
  5433 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5434 jobs to provide advice on the provability of subgoals.
  5435 
  5436 * Theory OrderedGroup and Ring_and_Field: various additions and
  5437 improvements to faciliate calculations involving equalities and
  5438 inequalities.
  5439 
  5440 The following theorems have been eliminated or modified
  5441 (INCOMPATIBILITY):
  5442 
  5443   abs_eq             now named abs_of_nonneg
  5444   abs_of_ge_0        now named abs_of_nonneg
  5445   abs_minus_eq       now named abs_of_nonpos
  5446   imp_abs_id         now named abs_of_nonneg
  5447   imp_abs_neg_id     now named abs_of_nonpos
  5448   mult_pos           now named mult_pos_pos
  5449   mult_pos_le        now named mult_nonneg_nonneg
  5450   mult_pos_neg_le    now named mult_nonneg_nonpos
  5451   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5452   mult_neg           now named mult_neg_neg
  5453   mult_neg_le        now named mult_nonpos_nonpos
  5454 
  5455 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5456      
  5457      zero_le_square
  5458      not_square_less_zero 
  5459 
  5460   The following lemmas have been deleted from Real/RealPow:
  5461   
  5462      realpow_zero_zero
  5463      realpow_two
  5464      realpow_less
  5465      zero_le_power
  5466      realpow_two_le
  5467      abs_realpow_two
  5468      realpow_two_abs     
  5469 
  5470 * Theory Parity: added rules for simplifying exponents.
  5471 
  5472 * Theory List:
  5473 
  5474 The following theorems have been eliminated or modified
  5475 (INCOMPATIBILITY):
  5476 
  5477   list_all_Nil       now named list_all.simps(1)
  5478   list_all_Cons      now named list_all.simps(2)
  5479   list_all_conv      now named list_all_iff
  5480   set_mem_eq         now named mem_iff
  5481 
  5482 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5483 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5484 
  5485 
  5486 *** HOL-Complex ***
  5487 
  5488 * Theory RealDef: better support for embedding natural numbers and
  5489 integers in the reals.
  5490 
  5491 The following theorems have been eliminated or modified
  5492 (INCOMPATIBILITY):
  5493 
  5494   exp_ge_add_one_self  now requires no hypotheses
  5495   real_of_int_add      reversed direction of equality (use [symmetric])
  5496   real_of_int_minus    reversed direction of equality (use [symmetric])
  5497   real_of_int_diff     reversed direction of equality (use [symmetric])
  5498   real_of_int_mult     reversed direction of equality (use [symmetric])
  5499 
  5500 * Theory RComplete: expanded support for floor and ceiling functions.
  5501 
  5502 * Theory Ln is new, with properties of the natural logarithm
  5503 
  5504 * Hyperreal: There is a new type constructor "star" for making
  5505 nonstandard types.  The old type names are now type synonyms:
  5506 
  5507   hypreal = real star
  5508   hypnat = nat star
  5509   hcomplex = complex star
  5510 
  5511 * Hyperreal: Many groups of similarly-defined constants have been
  5512 replaced by polymorphic versions (INCOMPATIBILITY):
  5513 
  5514   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5515 
  5516   starset      <-- starsetNat, starsetC
  5517   *s*          <-- *sNat*, *sc*
  5518   starset_n    <-- starsetNat_n, starsetC_n
  5519   *sn*         <-- *sNatn*, *scn*
  5520   InternalSets <-- InternalNatSets, InternalCSets
  5521 
  5522   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5523   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5524   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5525   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5526   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5527 
  5528 * Hyperreal: Many type-specific theorems have been removed in favor of
  5529 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5530 
  5531   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5532   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5533   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5534   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5535   right_minus <-- hypreal_add_minus
  5536   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5537   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5538   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5539   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5540   mult_1_right <-- hcomplex_mult_one_right
  5541   mult_zero_left <-- hcomplex_mult_zero_left
  5542   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5543   right_distrib <-- hypnat_add_mult_distrib2
  5544   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5545   right_inverse <-- hypreal_mult_inverse
  5546   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5547   order_refl <-- {hypreal,hypnat}_le_refl
  5548   order_trans <-- {hypreal,hypnat}_le_trans
  5549   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5550   order_less_le <-- {hypreal,hypnat}_less_le
  5551   linorder_linear <-- {hypreal,hypnat}_le_linear
  5552   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5553   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5554   add_nonneg_nonneg <-- hypreal_le_add_order
  5555 
  5556 * Hyperreal: Separate theorems having to do with type-specific
  5557 versions of constants have been merged into theorems that apply to the
  5558 new polymorphic constants (INCOMPATIBILITY):
  5559 
  5560   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5561   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5562   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5563   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5564   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5565   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5566   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5567   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5568   STAR_diff <-- {STAR,STARC}_diff
  5569   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5570     STARC_hcomplex_of_complex}_image_subset
  5571   starset_n_Un <-- starset{Nat,C}_n_Un
  5572   starset_n_Int <-- starset{Nat,C}_n_Int
  5573   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5574   starset_n_diff <-- starset{Nat,C}_n_diff
  5575   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5576   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5577   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5578   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5579   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5580   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5581   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5582   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5583   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5584   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5585   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5586   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5587   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5588   starfun_diff <-- starfun{C,RC,CR}_diff
  5589   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5590   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5591   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5592   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5593   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5594   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5595   starfun_Id <-- starfunC_Id
  5596   starfun_approx <-- starfun{Nat,CR}_approx
  5597   starfun_capprox <-- starfun{C,RC}_capprox
  5598   starfun_abs <-- starfunNat_rabs
  5599   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5600   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5601   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5602   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5603   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5604   starfun_add_approx <-- starfunCR_add_approx
  5605   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5606   starfun_divide <-- starfun{C,CR,RC}_divide
  5607   starfun_n <-- starfun{Nat,C}_n
  5608   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5609   starfun_n_add <-- starfun{Nat,C}_n_add
  5610   starfun_n_add_minus <-- starfunNat_n_add_minus
  5611   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5612   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5613   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5614 
  5615   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5616   star_n_minus <-- {hypreal,hcomplex}_minus
  5617   star_n_diff <-- {hypreal,hcomplex}_diff
  5618   star_n_mult <-- {hypreal,hcomplex}_mult
  5619   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5620   star_n_le <-- {hypreal,hypnat}_le
  5621   star_n_less <-- {hypreal,hypnat}_less
  5622   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5623   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5624   star_n_abs <-- hypreal_hrabs
  5625   star_n_divide <-- hcomplex_divide
  5626 
  5627   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5628   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5629   star_of_diff <-- hypreal_of_real_diff
  5630   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5631   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5632   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5633   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5634   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5635   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5636   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5637   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5638   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5639   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5640   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5641   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5642   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5643   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5644   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5645   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5646   star_of_power <-- hypreal_of_real_power
  5647   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5648 
  5649 * Hyperreal: new method "transfer" that implements the transfer
  5650 principle of nonstandard analysis. With a subgoal that mentions
  5651 nonstandard types like "'a star", the command "apply transfer"
  5652 replaces it with an equivalent one that mentions only standard types.
  5653 To be successful, all free variables must have standard types; non-
  5654 standard variables must have explicit universal quantifiers.
  5655 
  5656 * Hyperreal: A theory of Taylor series.
  5657 
  5658 
  5659 *** HOLCF ***
  5660 
  5661 * Discontinued special version of 'constdefs' (which used to support
  5662 continuous functions) in favor of the general Pure one with full
  5663 type-inference.
  5664 
  5665 * New simplification procedure for solving continuity conditions; it
  5666 is much faster on terms with many nested lambda abstractions (cubic
  5667 instead of exponential time).
  5668 
  5669 * New syntax for domain package: selector names are now optional.
  5670 Parentheses should be omitted unless argument is lazy, for example:
  5671 
  5672   domain 'a stream = cons "'a" (lazy "'a stream")
  5673 
  5674 * New command 'fixrec' for defining recursive functions with pattern
  5675 matching; defining multiple functions with mutual recursion is also
  5676 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5677 sinr, or any data constructor defined by the domain package. The given
  5678 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5679 syntax and examples.
  5680 
  5681 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5682 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5683 but the proof obligation additionally includes an admissibility
  5684 requirement. The packages generate instances of class cpo or pcpo,
  5685 with continuity and strictness theorems for Rep and Abs.
  5686 
  5687 * HOLCF: Many theorems have been renamed according to a more standard naming
  5688 scheme (INCOMPATIBILITY):
  5689 
  5690   foo_inject:  "foo$x = foo$y ==> x = y"
  5691   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5692   foo_less:    "(foo$x << foo$y) = (x << y)"
  5693   foo_strict:  "foo$UU = UU"
  5694   foo_defined: "... ==> foo$x ~= UU"
  5695   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5696 
  5697 
  5698 *** ZF ***
  5699 
  5700 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5701 including the First Isomorphism Theorem (on quotienting by the kernel
  5702 of a homomorphism).
  5703 
  5704 * ZF/Simplifier: install second copy of type solver that actually
  5705 makes use of TC rules declared to Isar proof contexts (or locales);
  5706 the old version is still required for ML proof scripts.
  5707 
  5708 
  5709 *** Cube ***
  5710 
  5711 * Converted to Isar theory format; use locales instead of axiomatic
  5712 theories.
  5713 
  5714 
  5715 *** ML ***
  5716 
  5717 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5718 for ||>, ||>>, |>>,
  5719 
  5720 * Pure/library.ML no longer defines its own option datatype, but uses
  5721 that of the SML basis, which has constructors NONE and SOME instead of
  5722 None and Some, as well as exception Option.Option instead of OPTION.
  5723 The functions the, if_none, is_some, is_none have been adapted
  5724 accordingly, while Option.map replaces apsome.
  5725 
  5726 * Pure/library.ML: the exception LIST has been given up in favour of
  5727 the standard exceptions Empty and Subscript, as well as
  5728 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5729 superceded by the standard hd and tl functions etc.
  5730 
  5731 A number of basic list functions are no longer exported to the ML
  5732 toplevel, as they are variants of predefined functions.  The following
  5733 suggests how one can translate existing code:
  5734 
  5735     rev_append xs ys = List.revAppend (xs, ys)
  5736     nth_elem (i, xs) = List.nth (xs, i)
  5737     last_elem xs = List.last xs
  5738     flat xss = List.concat xss
  5739     seq fs = List.app fs
  5740     partition P xs = List.partition P xs
  5741     mapfilter f xs = List.mapPartial f xs
  5742 
  5743 * Pure/library.ML: several combinators for linear functional
  5744 transformations, notably reverse application and composition:
  5745 
  5746   x |> f                f #> g
  5747   (x, y) |-> f          f #-> g
  5748 
  5749 * Pure/library.ML: introduced/changed precedence of infix operators:
  5750 
  5751   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5752   infix 2 ?;
  5753   infix 3 o oo ooo oooo;
  5754   infix 4 ~~ upto downto;
  5755 
  5756 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5757 infix operators.
  5758 
  5759 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5760 fold_map support linear functional transformations and nesting.  For
  5761 example:
  5762 
  5763   fold f [x1, ..., xN] y =
  5764     y |> f x1 |> ... |> f xN
  5765 
  5766   (fold o fold) f [xs1, ..., xsN] y =
  5767     y |> fold f xs1 |> ... |> fold f xsN
  5768 
  5769   fold f [x1, ..., xN] =
  5770     f x1 #> ... #> f xN
  5771 
  5772   (fold o fold) f [xs1, ..., xsN] =
  5773     fold f xs1 #> ... #> fold f xsN
  5774 
  5775 * Pure/library.ML: the following selectors on type 'a option are
  5776 available:
  5777 
  5778   the:               'a option -> 'a  (*partial*)
  5779   these:             'a option -> 'a  where 'a = 'b list
  5780   the_default: 'a -> 'a option -> 'a
  5781   the_list:          'a option -> 'a list
  5782 
  5783 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5784 basic operations for association lists, following natural argument
  5785 order; moreover the explicit equality predicate passed here avoids
  5786 potentially expensive polymorphic runtime equality checks.
  5787 The old functions may be expressed as follows:
  5788 
  5789   assoc = uncurry (AList.lookup (op =))
  5790   assocs = these oo AList.lookup (op =)
  5791   overwrite = uncurry (AList.update (op =)) o swap
  5792 
  5793 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5794 
  5795   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5796   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5797 
  5798 replacing make_keylist and keyfilter (occassionally used)
  5799 Naive rewrites:
  5800 
  5801   make_keylist = AList.make
  5802   keyfilter = AList.find (op =)
  5803 
  5804 * eq_fst and eq_snd now take explicit equality parameter, thus
  5805   avoiding eqtypes. Naive rewrites:
  5806 
  5807     eq_fst = eq_fst (op =)
  5808     eq_snd = eq_snd (op =)
  5809 
  5810 * Removed deprecated apl and apr (rarely used).
  5811   Naive rewrites:
  5812 
  5813     apl (n, op) =>>= curry op n
  5814     apr (op, m) =>>= fn n => op (n, m)
  5815 
  5816 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5817 provides a reasonably efficient light-weight implementation of sets as
  5818 lists.
  5819 
  5820 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5821 few new operations; existing lookup and update are now curried to
  5822 follow natural argument order (for use with fold etc.);
  5823 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5824 
  5825 * Pure/General: output via the Isabelle channels of
  5826 writeln/warning/error etc. is now passed through Output.output, with a
  5827 hook for arbitrary transformations depending on the print_mode
  5828 (cf. Output.add_mode -- the first active mode that provides a output
  5829 function wins).  Already formatted output may be embedded into further
  5830 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5831 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5832 accommodate easy composition of diagnostic messages etc.  Programmers
  5833 rarely need to care about Output.output or Output.raw at all, with
  5834 some notable exceptions: Output.output is required when bypassing the
  5835 standard channels (writeln etc.), or in token translations to produce
  5836 properly formatted results; Output.raw is required when capturing
  5837 already output material that will eventually be presented to the user
  5838 a second time.  For the default print mode, both Output.output and
  5839 Output.raw have no effect.
  5840 
  5841 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5842 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5843 cumulative results are displayed at the end of a batch session.
  5844 
  5845 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5846 replaced by File.platform_path and File.shell_path (with appropriate
  5847 hooks).  This provides a clean interface for unusual systems where the
  5848 internal and external process view of file names are different.
  5849 
  5850 * Pure: more efficient orders for basic syntactic entities: added
  5851 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5852 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5853 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5854 orders now -- potential INCOMPATIBILITY for code that depends on a
  5855 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5856 Library.sort_strings on result).
  5857 
  5858 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5859 fold_types traverse types/terms from left to right, observing natural
  5860 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5861 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5862 
  5863 * Pure: name spaces have been refined, with significant changes of the
  5864 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5865 to extern(_table).  The plain name entry path is superceded by a
  5866 general 'naming' context, which also includes the 'policy' to produce
  5867 a fully qualified name and external accesses of a fully qualified
  5868 name; NameSpace.extend is superceded by context dependent
  5869 Sign.declare_name.  Several theory and proof context operations modify
  5870 the naming context.  Especially note Theory.restore_naming and
  5871 ProofContext.restore_naming to get back to a sane state; note that
  5872 Theory.add_path is no longer sufficient to recover from
  5873 Theory.absolute_path in particular.
  5874 
  5875 * Pure: new flags short_names (default false) and unique_names
  5876 (default true) for controlling output of qualified names.  If
  5877 short_names is set, names are printed unqualified.  If unique_names is
  5878 reset, the name prefix is reduced to the minimum required to achieve
  5879 the original result when interning again, even if there is an overlap
  5880 with earlier declarations.
  5881 
  5882 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5883 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5884 (useful for printing error messages).  INCOMPATIBILITY.
  5885 
  5886 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5887 Theory.theory are now identified, referring to the universal
  5888 Context.theory (see Pure/context.ML).  Actual signature and theory
  5889 content is managed as theory data.  The old code and interfaces were
  5890 spread over many files and structures; the new arrangement introduces
  5891 considerable INCOMPATIBILITY to gain more clarity:
  5892 
  5893   Context -- theory management operations (name, identity, inclusion,
  5894     parents, ancestors, merge, etc.), plus generic theory data;
  5895 
  5896   Sign -- logical signature and syntax operations (declaring consts,
  5897     types, etc.), plus certify/read for common entities;
  5898 
  5899   Theory -- logical theory operations (stating axioms, definitions,
  5900     oracles), plus a copy of logical signature operations (consts,
  5901     types, etc.); also a few basic management operations (Theory.copy,
  5902     Theory.merge, etc.)
  5903 
  5904 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5905 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5906 for convenience -- they merely return the theory.
  5907 
  5908 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5909 
  5910 * Pure: the Isar proof context type is already defined early in Pure
  5911 as Context.proof (note that ProofContext.context and Proof.context are
  5912 aliases, where the latter is the preferred name).  This enables other
  5913 Isabelle components to refer to that type even before Isar is present.
  5914 
  5915 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5916 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5917 any of these kinds.  For example, Sign.intern typeK is now
  5918 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5919 Theory.hide_types.  Also note that former
  5920 Theory.hide_classes/types/consts are now
  5921 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5922 internalize their arguments!  INCOMPATIBILITY.
  5923 
  5924 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5925 datatype thmref (with constructors Name and NameSelection) instead of
  5926 plain string -- INCOMPATIBILITY;
  5927 
  5928 * Pure: cases produced by proof methods specify options, where NONE
  5929 means to remove case bindings -- INCOMPATIBILITY in
  5930 (RAW_)METHOD_CASES.
  5931 
  5932 * Pure: the following operations retrieve axioms or theorems from a
  5933 theory node or theory hierarchy, respectively:
  5934 
  5935   Theory.axioms_of: theory -> (string * term) list
  5936   Theory.all_axioms_of: theory -> (string * term) list
  5937   PureThy.thms_of: theory -> (string * thm) list
  5938   PureThy.all_thms_of: theory -> (string * thm) list
  5939 
  5940 * Pure: print_tac now outputs the goal through the trace channel.
  5941 
  5942 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5943 Reference Toplevel.debug (default false) controls detailed printing
  5944 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5945 controls execution profiling -- set to 1 for time and 2 for space
  5946 (both increase the runtime).
  5947 
  5948 * Isar session: The initial use of ROOT.ML is now always timed,
  5949 i.e. the log will show the actual process times, in contrast to the
  5950 elapsed wall-clock time that the outer shell wrapper produces.
  5951 
  5952 * Simplifier: improved handling of bound variables (nameless
  5953 representation, avoid allocating new strings).  Simprocs that invoke
  5954 the Simplifier recursively should use Simplifier.inherit_bounds to
  5955 avoid local name clashes.  Failure to do so produces warnings
  5956 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5957 for further details.
  5958 
  5959 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5960 bindings for all theorems stored within a given theory; this may help
  5961 in porting non-Isar theories to Isar ones, while keeping ML proof
  5962 scripts for the time being.
  5963 
  5964 * ML operator HTML.with_charset specifies the charset begin used for
  5965 generated HTML files.  For example:
  5966 
  5967   HTML.with_charset "utf-8" use_thy "Hebrew";
  5968   HTML.with_charset "utf-8" use_thy "Chinese";
  5969 
  5970 
  5971 *** System ***
  5972 
  5973 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5974 isabelle, isatool etc.).
  5975 
  5976 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5977 isatool doc, isatool mkdir, display_drafts etc.).
  5978 
  5979 * isatool usedir: option -f allows specification of the ML file to be
  5980 used by Isabelle; default is ROOT.ML.
  5981 
  5982 * New isatool version outputs the version identifier of the Isabelle
  5983 distribution being used.
  5984 
  5985 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5986 (containing Boolean satisfiability problems) into Isabelle/HOL
  5987 theories.
  5988 
  5989 
  5990 
  5991 New in Isabelle2004 (April 2004)
  5992 --------------------------------
  5993 
  5994 *** General ***
  5995 
  5996 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5997   Replaces linorder.ML.
  5998 
  5999 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6000   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6001   (\<a>...\<z>), are now considered normal letters, and can therefore
  6002   be used anywhere where an ASCII letter (a...zA...Z) has until
  6003   now. COMPATIBILITY: This obviously changes the parsing of some
  6004   terms, especially where a symbol has been used as a binder, say
  6005   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6006   as an identifier.  Fix it by inserting a space around former
  6007   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6008   existing theory and ML files.
  6009 
  6010 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6011 
  6012 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6013   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6014   a normal (but invisible) letter. For multiple letter subscripts repeat
  6015   \<^isub> like this: x\<^isub>1\<^isub>2.
  6016 
  6017 * Pure: There are now sub-/superscripts that can span more than one
  6018   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6019   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6020   superscript. The new control characters are not identifier parts.
  6021 
  6022 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6023   content of "..." to the latex file instead of \isacntrl... . The "..."
  6024   may consist of any printable characters excluding the end bracket >.
  6025 
  6026 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6027   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6028   declare constants "final", which prevents their being given a definition
  6029   later.  It is useful for constants whose behaviour is fixed axiomatically
  6030   rather than definitionally, such as the meta-logic connectives.
  6031 
  6032 * Pure: 'instance' now handles general arities with general sorts
  6033   (i.e. intersections of classes),
  6034 
  6035 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6036   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6037   It can be changed to alter the colors/layout of generated pages.
  6038 
  6039 
  6040 *** Isar ***
  6041 
  6042 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6043   cut_tac, subgoal_tac and thin_tac:
  6044   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6045     locales are no longer forced to write Isar proof scripts.
  6046     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6047     emulations.
  6048   - INCOMPATIBILITY: names of variables to be instantiated may no
  6049     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6050     This is consistent with the instantiation attribute "where".
  6051 
  6052 * Attributes "where" and "of":
  6053   - Now take type variables of instantiated theorem into account when reading
  6054     the instantiation string.  This fixes a bug that caused instantiated
  6055     theorems to have too special types in some circumstances.
  6056   - "where" permits explicit instantiations of type variables.
  6057 
  6058 * Calculation commands "moreover" and "also" no longer interfere with
  6059   current facts ("this"), admitting arbitrary combinations with "then"
  6060   and derived forms.
  6061 
  6062 * Locales:
  6063   - Goal statements involving the context element "includes" no longer
  6064     generate theorems with internal delta predicates (those ending on
  6065     "_axioms") in the premise.
  6066     Resolve particular premise with <locale>.intro to obtain old form.
  6067   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6068     specification and "includes" elements in goal statement.
  6069   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6070     [intro?] and [elim?] (respectively) by default.
  6071   - Experimental command for instantiation of locales in proof contexts:
  6072         instantiate <label>[<attrs>]: <loc>
  6073     Instantiates locale <loc> and adds all its theorems to the current context
  6074     taking into account their attributes.  Label and attrs are optional
  6075     modifiers, like in theorem declarations.  If present, names of
  6076     instantiated theorems are qualified with <label>, and the attributes
  6077     <attrs> are applied after any attributes these theorems might have already.
  6078       If the locale has assumptions, a chained fact of the form
  6079     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6080     are derived.  The command does not support old-style locales declared
  6081     with "locale (open)".
  6082       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6083 
  6084 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6085   (Isar) contexts.
  6086 
  6087 
  6088 *** HOL ***
  6089 
  6090 * Proof import: new image HOL4 contains the imported library from
  6091   the HOL4 system with about 2500 theorems. It is imported by
  6092   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6093   can be used like any other Isabelle image.  See
  6094   HOL/Import/HOL/README for more information.
  6095 
  6096 * Simplifier:
  6097   - Much improved handling of linear and partial orders.
  6098     Reasoners for linear and partial orders are set up for type classes
  6099     "linorder" and "order" respectively, and are added to the default simpset
  6100     as solvers.  This means that the simplifier can build transitivity chains
  6101     to solve goals from the assumptions.
  6102   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6103     of blast or auto after simplification become unnecessary because the goal
  6104     is solved by simplification already.
  6105 
  6106 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6107     all proved in axiomatic type classes for semirings, rings and fields.
  6108 
  6109 * Numerics:
  6110   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6111     now formalized using the Ring_and_Field theory mentioned above.
  6112   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6113     than before, because now they are set up once in a generic manner.
  6114   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6115     Look for the general versions in Ring_and_Field (and Power if they concern
  6116     exponentiation).
  6117 
  6118 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6119 
  6120 * Records:
  6121   - Record types are now by default printed with their type abbreviation
  6122     instead of the list of all field types. This can be configured via
  6123     the reference "print_record_type_abbr".
  6124   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6125     (not enabled by default).
  6126   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6127     EX x. x = sel r to True (not enabled by default).
  6128   - Tactic "record_split_simp_tac" to split and simplify records added.
  6129 
  6130 * 'specification' command added, allowing for definition by
  6131   specification.  There is also an 'ax_specification' command that
  6132   introduces the new constants axiomatically.
  6133 
  6134 * arith(_tac) is now able to generate counterexamples for reals as well.
  6135 
  6136 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6137 
  6138 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6139   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6140 
  6141 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6142   matrix theory to linear programming.
  6143 
  6144 * Unions and Intersections:
  6145   The latex output syntax of UN and INT has been changed
  6146   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6147   i.e. the index formulae has become a subscript.
  6148   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6149 
  6150 * Unions and Intersections over Intervals:
  6151   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6152   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6153   like in normal math, and corresponding versions for < and for intersection.
  6154 
  6155 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6156   lexicographic dictonary ordering has been added as "lexord".
  6157 
  6158 * ML: the legacy theory structures Int and List have been removed. They had
  6159   conflicted with ML Basis Library structures having the same names.
  6160 
  6161 * 'refute' command added to search for (finite) countermodels.  Only works
  6162   for a fragment of HOL.  The installation of an external SAT solver is
  6163   highly recommended.  See "HOL/Refute.thy" for details.
  6164 
  6165 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6166   formulae under an assignment of free variables to random values.
  6167   In contrast to 'refute', it can deal with inductive datatypes,
  6168   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6169   for examples.
  6170 
  6171 
  6172 *** HOLCF ***
  6173 
  6174 * Streams now come with concatenation and are part of the HOLCF image
  6175 
  6176 
  6177 
  6178 New in Isabelle2003 (May 2003)
  6179 ------------------------------
  6180 
  6181 *** General ***
  6182 
  6183 * Provers/simplifier:
  6184 
  6185   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6186     Assumptions are now subject to complete mutual simplification,
  6187     not just from left to right. The simplifier now preserves
  6188     the order of assumptions.
  6189 
  6190     Potential INCOMPATIBILITY:
  6191 
  6192     -- simp sometimes diverges where the old version did
  6193        not, e.g. invoking simp on the goal
  6194 
  6195         [| P (f x); y = x; f x = f y |] ==> Q
  6196 
  6197        now gives rise to the infinite reduction sequence
  6198 
  6199         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6200 
  6201        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6202        kind of problem.
  6203 
  6204     -- Tactics combining classical reasoner and simplification (such as auto)
  6205        are also affected by this change, because many of them rely on
  6206        simp. They may sometimes diverge as well or yield a different numbers
  6207        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6208        in case of problems. Sometimes subsequent calls to the classical
  6209        reasoner will fail because a preceeding call to the simplifier too
  6210        eagerly simplified the goal, e.g. deleted redundant premises.
  6211 
  6212   - The simplifier trace now shows the names of the applied rewrite rules
  6213 
  6214   - You can limit the number of recursive invocations of the simplifier
  6215     during conditional rewriting (where the simplifie tries to solve the
  6216     conditions before applying the rewrite rule):
  6217     ML "simp_depth_limit := n"
  6218     where n is an integer. Thus you can force termination where previously
  6219     the simplifier would diverge.
  6220 
  6221   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6222 
  6223   - No longer aborts on failed congruence proof.  Instead, the
  6224     congruence is ignored.
  6225 
  6226 * Pure: New generic framework for extracting programs from constructive
  6227   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6228   as HOL/Extraction for some case studies.
  6229 
  6230 * Pure: The main goal of the proof state is no longer shown by default, only
  6231 the subgoals. This behaviour is controlled by a new flag.
  6232    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6233 (ML: Proof.show_main_goal).
  6234 
  6235 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6236 rules whose conclusion matches subgoal 1:
  6237       PG menu: Isabelle/Isar -> Show me -> matching rules
  6238 The rules are ordered by how closely they match the subgoal.
  6239 In particular, rules that solve a subgoal outright are displayed first
  6240 (or rather last, the way they are printed).
  6241 (ML: ProofGeneral.print_intros())
  6242 
  6243 * Pure: New flag trace_unify_fail causes unification to print
  6244 diagnostic information (PG: in trace buffer) when it fails. This is
  6245 useful for figuring out why single step proofs like rule, erule or
  6246 assumption failed.
  6247 
  6248 * Pure: Locale specifications now produce predicate definitions
  6249 according to the body of text (covering assumptions modulo local
  6250 definitions); predicate "loc_axioms" covers newly introduced text,
  6251 while "loc" is cumulative wrt. all included locale expressions; the
  6252 latter view is presented only on export into the global theory
  6253 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6254 on the old view without predicates;
  6255 
  6256 * Pure: predefined locales "var" and "struct" are useful for sharing
  6257 parameters (as in CASL, for example); just specify something like
  6258 ``var x + var y + struct M'' as import;
  6259 
  6260 * Pure: improved thms_containing: proper indexing of facts instead of
  6261 raw theorems; check validity of results wrt. current name space;
  6262 include local facts of proof configuration (also covers active
  6263 locales), cover fixed variables in index; may use "_" in term
  6264 specification; an optional limit for the number of printed facts may
  6265 be given (the default is 40);
  6266 
  6267 * Pure: disallow duplicate fact bindings within new-style theory files
  6268 (batch-mode only);
  6269 
  6270 * Provers: improved induct method: assumptions introduced by case
  6271 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6272 the goal statement); "foo" still refers to all facts collectively;
  6273 
  6274 * Provers: the function blast.overloaded has been removed: all constants
  6275 are regarded as potentially overloaded, which improves robustness in exchange
  6276 for slight decrease in efficiency;
  6277 
  6278 * Provers/linorder: New generic prover for transitivity reasoning over
  6279 linear orders.  Note: this prover is not efficient!
  6280 
  6281 * Isar: preview of problems to finish 'show' now produce an error
  6282 rather than just a warning (in interactive mode);
  6283 
  6284 
  6285 *** HOL ***
  6286 
  6287 * arith(_tac)
  6288 
  6289  - Produces a counter example if it cannot prove a goal.
  6290    Note that the counter example may be spurious if the goal is not a formula
  6291    of quantifier-free linear arithmetic.
  6292    In ProofGeneral the counter example appears in the trace buffer.
  6293 
  6294  - Knows about div k and mod k where k is a numeral of type nat or int.
  6295 
  6296  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6297    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6298    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6299 
  6300 * simp's arithmetic capabilities have been enhanced a bit: it now
  6301 takes ~= in premises into account (by performing a case split);
  6302 
  6303 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6304 are distributed over a sum of terms;
  6305 
  6306 * New tactic "trans_tac" and method "trans" instantiate
  6307 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6308 "<=", "<" and "=").
  6309 
  6310 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6311 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6312 
  6313 * 'typedef' command has new option "open" to suppress the set
  6314 definition;
  6315 
  6316 * functions Min and Max on finite sets have been introduced (theory
  6317 Finite_Set);
  6318 
  6319 * attribute [symmetric] now works for relations as well; it turns
  6320 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6321 
  6322 * induct over a !!-quantified statement (say !!x1..xn):
  6323   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6324 
  6325 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6326 %x. None. Warning: empty_def now refers to the previously hidden definition
  6327 of the empty set.
  6328 
  6329 * Algebra: formalization of classical algebra.  Intended as base for
  6330 any algebraic development in Isabelle.  Currently covers group theory
  6331 (up to Sylow's theorem) and ring theory (Universal Property of
  6332 Univariate Polynomials).  Contributions welcome;
  6333 
  6334 * GroupTheory: deleted, since its material has been moved to Algebra;
  6335 
  6336 * Complex: new directory of the complex numbers with numeric constants,
  6337 nonstandard complex numbers, and some complex analysis, standard and
  6338 nonstandard (Jacques Fleuriot);
  6339 
  6340 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6341 
  6342 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6343 Fleuriot);
  6344 
  6345 * Real/HahnBanach: updated and adapted to locales;
  6346 
  6347 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6348 Gray and Kramer);
  6349 
  6350 * UNITY: added the Meier-Sanders theory of progress sets;
  6351 
  6352 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6353 as abstract algorithms, instantiated to the JVM;
  6354 
  6355 * Bali: Java source language formalization. Type system, operational
  6356 semantics, axiomatic semantics. Supported language features:
  6357 classes, interfaces, objects,virtual methods, static methods,
  6358 static/instance fields, arrays, access modifiers, definite
  6359 assignment, exceptions.
  6360 
  6361 
  6362 *** ZF ***
  6363 
  6364 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6365 universe, etc.);
  6366 
  6367 * Main ZF: virtually all theories converted to new-style format;
  6368 
  6369 
  6370 *** ML ***
  6371 
  6372 * Pure: Tactic.prove provides sane interface for internal proofs;
  6373 omits the infamous "standard" operation, so this is more appropriate
  6374 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6375 
  6376 * Pure: improved error reporting of simprocs;
  6377 
  6378 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6379 up simprocs;
  6380 
  6381 
  6382 *** Document preparation ***
  6383 
  6384 * uses \par instead of \\ for line breaks in theory text. This may
  6385 shift some page breaks in large documents. To get the old behaviour
  6386 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6387 
  6388 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6389 other packages
  6390 
  6391 * \<euro> now needs package babel/greek instead of marvosym (which
  6392 broke \Rightarrow)
  6393 
  6394 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6395 textcomp package)
  6396 
  6397 
  6398 
  6399 New in Isabelle2002 (March 2002)
  6400 --------------------------------
  6401 
  6402 *** Document preparation ***
  6403 
  6404 * greatly simplified document preparation setup, including more
  6405 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6406 instructive isatool mkdir; users should basically be able to get
  6407 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6408 users may run a separate document processing stage manually like this:
  6409 "isatool usedir -D output HOL Test && isatool document Test/output";
  6410 
  6411 * theory dependency graph may now be incorporated into documents;
  6412 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6413 with \includegraphics of LaTeX;
  6414 
  6415 * proper spacing of consecutive markup elements, especially text
  6416 blocks after section headings;
  6417 
  6418 * support bold style (for single symbols only), input syntax is like
  6419 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6420 
  6421 * \<bullet> is now output as bold \cdot by default, which looks much
  6422 better in printed text;
  6423 
  6424 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6425 note that these symbols are currently unavailable in Proof General /
  6426 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6427 
  6428 * isatool latex no longer depends on changed TEXINPUTS, instead
  6429 isatool document copies the Isabelle style files to the target
  6430 location;
  6431 
  6432 
  6433 *** Isar ***
  6434 
  6435 * Pure/Provers: improved proof by cases and induction;
  6436   - 'case' command admits impromptu naming of parameters (such as
  6437     "case (Suc n)");
  6438   - 'induct' method divinates rule instantiation from the inductive
  6439     claim; no longer requires excessive ?P bindings for proper
  6440     instantiation of cases;
  6441   - 'induct' method properly enumerates all possibilities of set/type
  6442     rules; as a consequence facts may be also passed through *type*
  6443     rules without further ado;
  6444   - 'induct' method now derives symbolic cases from the *rulified*
  6445     rule (before it used to rulify cases stemming from the internal
  6446     atomized version); this means that the context of a non-atomic
  6447     statement becomes is included in the hypothesis, avoiding the
  6448     slightly cumbersome show "PROP ?case" form;
  6449   - 'induct' may now use elim-style induction rules without chaining
  6450     facts, using ``missing'' premises from the goal state; this allows
  6451     rules stemming from inductive sets to be applied in unstructured
  6452     scripts, while still benefitting from proper handling of non-atomic
  6453     statements; NB: major inductive premises need to be put first, all
  6454     the rest of the goal is passed through the induction;
  6455   - 'induct' proper support for mutual induction involving non-atomic
  6456     rule statements (uses the new concept of simultaneous goals, see
  6457     below);
  6458   - append all possible rule selections, but only use the first
  6459     success (no backtracking);
  6460   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6461   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6462   - added 'print_induct_rules' (covered by help item in recent Proof
  6463     General versions);
  6464   - moved induct/cases attributes to Pure, methods to Provers;
  6465   - generic method setup instantiated for FOL and HOL;
  6466 
  6467 * Pure: support multiple simultaneous goal statements, for example
  6468 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6469 meta-level mechanism, this acts as if several individual goals had
  6470 been stated separately; in particular common proof methods need to be
  6471 repeated in order to cover all claims; note that a single elimination
  6472 step is *not* sufficient to establish the two conjunctions, so this
  6473 fails:
  6474 
  6475   assume "A & B" then have A and B ..   (*".." fails*)
  6476 
  6477 better use "obtain" in situations as above; alternative refer to
  6478 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6479 
  6480 * Pure: proper integration with ``locales''; unlike the original
  6481 version by Florian Kammller, Isar locales package high-level proof
  6482 contexts rather than raw logical ones (e.g. we admit to include
  6483 attributes everywhere); operations on locales include merge and
  6484 rename; support for implicit arguments (``structures''); simultaneous
  6485 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6486 some examples;
  6487 
  6488 * Pure: the following commands have been ``localized'', supporting a
  6489 target locale specification "(in name)": 'lemma', 'theorem',
  6490 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6491 stored both within the locale and at the theory level (exported and
  6492 qualified by the locale name);
  6493 
  6494 * Pure: theory goals may now be specified in ``long'' form, with
  6495 ad-hoc contexts consisting of arbitrary locale elements. for example
  6496 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6497 definitions may be given, too); the result is a meta-level rule with
  6498 the context elements being discharged in the obvious way;
  6499 
  6500 * Pure: new proof command 'using' allows to augment currently used
  6501 facts after a goal statement ('using' is syntactically analogous to
  6502 'apply', but acts on the goal's facts only); this allows chained facts
  6503 to be separated into parts given before and after a claim, as in
  6504 ``from a and b have C using d and e <proof>'';
  6505 
  6506 * Pure: renamed "antecedent" case to "rule_context";
  6507 
  6508 * Pure: new 'judgment' command records explicit information about the
  6509 object-logic embedding (used by several tools internally); no longer
  6510 use hard-wired "Trueprop";
  6511 
  6512 * Pure: added 'corollary' command;
  6513 
  6514 * Pure: fixed 'token_translation' command;
  6515 
  6516 * Pure: removed obsolete 'exported' attribute;
  6517 
  6518 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6519 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6520 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6521 
  6522 * Pure: method 'atomize' presents local goal premises as object-level
  6523 statements (atomic meta-level propositions); setup controlled via
  6524 rewrite rules declarations of 'atomize' attribute; example
  6525 application: 'induct' method with proper rule statements in improper
  6526 proof *scripts*;
  6527 
  6528 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6529 now consider the syntactic context of assumptions, giving a better
  6530 chance to get type-inference of the arguments right (this is
  6531 especially important for locales);
  6532 
  6533 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6534 mode;
  6535 
  6536 * Pure/obtain: the formal conclusion "thesis", being marked as
  6537 ``internal'', may no longer be reference directly in the text;
  6538 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6539 situations;
  6540 
  6541 * Pure: generic 'sym' attribute which declares a rule both as pure
  6542 'elim?' and for the 'symmetric' operation;
  6543 
  6544 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6545 text; the fixed correlation with particular command syntax has been
  6546 discontinued;
  6547 
  6548 * Pure: new method 'rules' is particularly well-suited for proof
  6549 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6550 but often produces more compact proof terms with less detours;
  6551 
  6552 * Pure/Provers/classical: simplified integration with pure rule
  6553 attributes and methods; the classical "intro?/elim?/dest?"
  6554 declarations coincide with the pure ones; the "rule" method no longer
  6555 includes classically swapped intros; "intro" and "elim" methods no
  6556 longer pick rules from the context; also got rid of ML declarations
  6557 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6558 INCOMPATIBILITY;
  6559 
  6560 * Provers/classical: attribute 'swapped' produces classical inversions
  6561 of introduction rules;
  6562 
  6563 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6564 rules instead of full simplifier context; 'iff' attribute handles
  6565 conditional rules;
  6566 
  6567 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6568 
  6569 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6570 "(permissive)" option to recover old behavior;
  6571 
  6572 * HOL: 'inductive' no longer features separate (collective) attributes
  6573 for 'intros' (was found too confusing);
  6574 
  6575 * HOL: properly declared induction rules less_induct and
  6576 wf_induct_rule;
  6577 
  6578 
  6579 *** HOL ***
  6580 
  6581 * HOL: moved over to sane numeral syntax; the new policy is as
  6582 follows:
  6583 
  6584   - 0 and 1 are polymorphic constants, which are defined on any
  6585   numeric type (nat, int, real etc.);
  6586 
  6587   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6588   binary representation internally;
  6589 
  6590   - type nat has special constructor Suc, and generally prefers Suc 0
  6591   over 1::nat and Suc (Suc 0) over 2::nat;
  6592 
  6593 This change may cause significant problems of INCOMPATIBILITY; here
  6594 are some hints on converting existing sources:
  6595 
  6596   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6597   entities, so expressions involving "-" (unary or binary minus) need
  6598   to be spaced properly;
  6599 
  6600   - existing occurrences of "1" may need to be constraint "1::nat" or
  6601   even replaced by Suc 0; similar for old "2";
  6602 
  6603   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6604 
  6605   - remove all special provisions on numerals in proofs;
  6606 
  6607 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6608 representation (depends on bin_arith_simps in the default context);
  6609 
  6610 * HOL: symbolic syntax for x^2 (numeral 2);
  6611 
  6612 * HOL: the class of all HOL types is now called "type" rather than
  6613 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6614 in axclass/classes, instance/arities, and (usually rare) occurrences
  6615 in typings (of consts etc.); internally the class is called
  6616 "HOL.type", ML programs should refer to HOLogic.typeS;
  6617 
  6618 * HOL/record package improvements:
  6619   - new derived operations "fields" to build a partial record section,
  6620     "extend" to promote a fixed record to a record scheme, and
  6621     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6622     declared as simp by default;
  6623   - shared operations ("more", "fields", etc.) now need to be always
  6624     qualified) --- potential INCOMPATIBILITY;
  6625   - removed "make_scheme" operations (use "make" with "extend") --
  6626     INCOMPATIBILITY;
  6627   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6628   - provides cases/induct rules for use with corresponding Isar
  6629     methods (for concrete records, record schemes, concrete more
  6630     parts, and schematic more parts -- in that order);
  6631   - internal definitions directly based on a light-weight abstract
  6632     theory of product types over typedef rather than datatype;
  6633 
  6634 * HOL: generic code generator for generating executable ML code from
  6635 specifications; specific support for HOL constructs such as inductive
  6636 datatypes and sets, as well as recursive functions; can be invoked
  6637 via 'generate_code' theory section;
  6638 
  6639 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6640 
  6641 * HOL: consolidated and renamed several theories.  In particular:
  6642         Ord.thy has been absorbed into HOL.thy
  6643         String.thy has been absorbed into List.thy
  6644 
  6645 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6646 (beware of argument permutation!);
  6647 
  6648 * HOL: linorder_less_split superseded by linorder_cases;
  6649 
  6650 * HOL/List: "nodups" renamed to "distinct";
  6651 
  6652 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6653 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6654   - Ex_def has changed, now need to use some_eq_ex
  6655 
  6656 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6657 in this (rare) case use:
  6658 
  6659   delSWrapper "split_all_tac"
  6660   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6661 
  6662 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6663 MAY FAIL;
  6664 
  6665 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6666 Isabelle's type classes, ^ on functions and relations has too general
  6667 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6668 necessary to attach explicit type constraints;
  6669 
  6670 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6671 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6672 renamed accordingly (eg "compI" -> "rel_compI").
  6673 
  6674 * HOL: syntax translations now work properly with numerals and records
  6675 expressions;
  6676 
  6677 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6678 of "lam" -- INCOMPATIBILITY;
  6679 
  6680 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6681 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6682 renamed "Product_Type.unit";
  6683 
  6684 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6685 
  6686 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6687 the "cases" method);
  6688 
  6689 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6690 Florian Kammller);
  6691 
  6692 * HOL/IMP: updated and converted to new-style theory format; several
  6693 parts turned into readable document, with proper Isar proof texts and
  6694 some explanations (by Gerwin Klein);
  6695 
  6696 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6697 
  6698 * HOL-Hyperreal is now a logic image;
  6699 
  6700 
  6701 *** HOLCF ***
  6702 
  6703 * Isar: consts/constdefs supports mixfix syntax for continuous
  6704 operations;
  6705 
  6706 * Isar: domain package adapted to new-style theory format, e.g. see
  6707 HOLCF/ex/Dnat.thy;
  6708 
  6709 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6710 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6711 lift.induct_tac, always use UU instead of Undef;
  6712 
  6713 * HOLCF/IMP: updated and converted to new-style theory;
  6714 
  6715 
  6716 *** ZF ***
  6717 
  6718 * Isar: proper integration of logic-specific tools and packages,
  6719 including theory commands '(co)inductive', '(co)datatype',
  6720 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6721 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6722 
  6723 * theory Main no longer includes AC; for the Axiom of Choice, base
  6724 your theory on Main_ZFC;
  6725 
  6726 * the integer library now covers quotients and remainders, with many
  6727 laws relating division to addition, multiplication, etc.;
  6728 
  6729 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6730 typeless version of the formalism;
  6731 
  6732 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6733 format;
  6734 
  6735 * ZF/Induct: new directory for examples of inductive definitions,
  6736 including theory Multiset for multiset orderings; converted to
  6737 new-style theory format;
  6738 
  6739 * ZF: many new theorems about lists, ordinals, etc.;
  6740 
  6741 
  6742 *** General ***
  6743 
  6744 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6745 variable proof controls level of detail: 0 = no proofs (only oracle
  6746 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6747 also ref manual for further ML interfaces;
  6748 
  6749 * Pure/axclass: removed obsolete ML interface
  6750 goal_subclass/goal_arity;
  6751 
  6752 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6753 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6754 separate tokens, so expressions involving minus need to be spaced
  6755 properly;
  6756 
  6757 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6758 rather than "infixl" or "infixr";
  6759 
  6760 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6761 sort constraint specifications in type inference; e.g. "x::_::foo"
  6762 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6763 type variable);
  6764 
  6765 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6766 control output of nested => (types); the default behavior is
  6767 "type_brackets";
  6768 
  6769 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6770 tokens into AST constants;
  6771 
  6772 * Pure/syntax: prefer later declarations of translations and print
  6773 translation functions; potential INCOMPATIBILITY: need to reverse
  6774 multiple declarations for same syntax element constant;
  6775 
  6776 * Pure/show_hyps reset by default (in accordance to existing Isar
  6777 practice);
  6778 
  6779 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6780 addSafter;
  6781 
  6782 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6783 as well;
  6784 
  6785 * system: tested support for MacOS X; should be able to get Isabelle +
  6786 Proof General to work in a plain Terminal after installing Poly/ML
  6787 (e.g. from the Isabelle distribution area) and GNU bash alone
  6788 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6789 support requires further installations, e.g. from
  6790 http://fink.sourceforge.net/);
  6791 
  6792 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6793 
  6794 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6795 of 40 MB), cf. ML_OPTIONS;
  6796 
  6797 * system: Proof General keywords specification is now part of the
  6798 Isabelle distribution (see etc/isar-keywords.el);
  6799 
  6800 * system: support for persistent Proof General sessions (refrain from
  6801 outdating all loaded theories on startup); user may create writable
  6802 logic images like this: ``isabelle -q HOL Test'';
  6803 
  6804 * system: smart selection of Isabelle process versus Isabelle
  6805 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6806 run both "isabelle" and "Isabelle" even if file names are badly
  6807 damaged (executable inspects the case of the first letter of its own
  6808 name); added separate "isabelle-process" and "isabelle-interface";
  6809 
  6810 * system: refrain from any attempt at filtering input streams; no
  6811 longer support ``8bit'' encoding of old isabelle font, instead proper
  6812 iso-latin characters may now be used; the related isatools
  6813 "symbolinput" and "nonascii" have disappeared as well;
  6814 
  6815 * system: removed old "xterm" interface (the print modes "xterm" and
  6816 "xterm_color" are still available for direct use in a suitable
  6817 terminal);
  6818 
  6819 
  6820 
  6821 New in Isabelle99-2 (February 2001)
  6822 -----------------------------------
  6823 
  6824 *** Overview of INCOMPATIBILITIES ***
  6825 
  6826 * HOL: please note that theories in the Library and elsewhere often use the
  6827 new-style (Isar) format; to refer to their theorems in an ML script you must
  6828 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6829 
  6830 * HOL: inductive package no longer splits induction rule aggressively,
  6831 but only as far as specified by the introductions given; the old
  6832 format may be recovered via ML function complete_split_rule or attribute
  6833 'split_rule (complete)';
  6834 
  6835 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6836 gfp_Tarski to gfp_unfold;
  6837 
  6838 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6839 
  6840 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6841 relation); infix "^^" has been renamed "``"; infix "``" has been
  6842 renamed "`"; "univalent" has been renamed "single_valued";
  6843 
  6844 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6845 operation;
  6846 
  6847 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6848 
  6849 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6850 
  6851 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6852 consequence, it is no longer monotonic wrt. the local goal context
  6853 (which is now passed through the inductive cases);
  6854 
  6855 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6856 \<gg> to \<ggreater>;
  6857 
  6858 
  6859 *** Document preparation ***
  6860 
  6861 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6862 available: are "it" for near math-mode best-style output, "sl" for
  6863 slanted text style, and "tt" for plain type-writer; if no
  6864 \isabellestyle command is given, output is according to slanted
  6865 type-writer);
  6866 
  6867 * support sub/super scripts (for single symbols only), input syntax is
  6868 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6869 
  6870 * some more standard symbols; see Appendix A of the system manual for
  6871 the complete list of symbols defined in isabellesym.sty;
  6872 
  6873 * improved isabelle style files; more abstract symbol implementation
  6874 (should now use \isamath{...} and \isatext{...} in custom symbol
  6875 definitions);
  6876 
  6877 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6878 state; Note that presentation of goal states does not conform to
  6879 actual human-readable proof documents.  Please do not include goal
  6880 states into document output unless you really know what you are doing!
  6881 
  6882 * proper indentation of antiquoted output with proportional LaTeX
  6883 fonts;
  6884 
  6885 * no_document ML operator temporarily disables LaTeX document
  6886 generation;
  6887 
  6888 * isatool unsymbolize tunes sources for plain ASCII communication;
  6889 
  6890 
  6891 *** Isar ***
  6892 
  6893 * Pure: Isar now suffers initial goal statements to contain unbound
  6894 schematic variables (this does not conform to actual readable proof
  6895 documents, due to unpredictable outcome and non-compositional proof
  6896 checking); users who know what they are doing may use schematic goals
  6897 for Prolog-style synthesis of proven results;
  6898 
  6899 * Pure: assumption method (an implicit finishing) now handles actual
  6900 rules as well;
  6901 
  6902 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6903 initial goal, declare "that" only as Pure intro (only for single
  6904 steps); the "that" rule assumption may now be involved in implicit
  6905 finishing, thus ".." becomes a feasible for trivial obtains;
  6906 
  6907 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6908 instance proofs may be performed by "..";
  6909 
  6910 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6911 statements as well;
  6912 
  6913 * Pure: more robust selection of calculational rules;
  6914 
  6915 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6916 rule (as well as the assumption rule);
  6917 
  6918 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6919 lemmas, using the graph browser tool;
  6920 
  6921 * Pure: predict failure of "show" in interactive mode;
  6922 
  6923 * Pure: 'thms_containing' now takes actual terms as arguments;
  6924 
  6925 * HOL: improved method 'induct' --- now handles non-atomic goals
  6926 (potential INCOMPATIBILITY); tuned error handling;
  6927 
  6928 * HOL: cases and induct rules now provide explicit hints about the
  6929 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6930 any remaining facts are inserted into the goal verbatim;
  6931 
  6932 * HOL: local contexts (aka cases) may now contain term bindings as
  6933 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6934 the result to be shown in each case;
  6935 
  6936 * HOL: added 'recdef_tc' command;
  6937 
  6938 * isatool convert assists in eliminating legacy ML scripts;
  6939 
  6940 
  6941 *** HOL ***
  6942 
  6943 * HOL/Library: a collection of generic theories to be used together
  6944 with main HOL; the theory loader path already includes this directory
  6945 by default; the following existing theories have been moved here:
  6946 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6947 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6948 
  6949 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6950 modelling and verification task performed in Isabelle/HOL +
  6951 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6952 
  6953 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6954 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6955 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6956 'domain', this makes the theory consistent with mathematical
  6957 literature;
  6958 
  6959 * HOL basics: added overloaded operations "inverse" and "divide"
  6960 (infix "/"), syntax for generic "abs" operation, generic summation
  6961 operator \<Sum>;
  6962 
  6963 * HOL/typedef: simplified package, provide more useful rules (see also
  6964 HOL/subset.thy);
  6965 
  6966 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6967 now expressed as a proper nested rule (old-style tactic scripts may
  6968 require atomize_strip_tac to cope with non-atomic premises);
  6969 
  6970 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6971 to "split_conv" (old name still available for compatibility);
  6972 
  6973 * HOL: improved concrete syntax for strings (e.g. allows translation
  6974 rules with string literals);
  6975 
  6976 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6977  and Fleuriot's mechanization of analysis, including the transcendental
  6978  functions for the reals;
  6979 
  6980 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6981 
  6982 
  6983 *** CTT ***
  6984 
  6985 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6986 "lam" is displayed as TWO lambda-symbols
  6987 
  6988 * CTT: theory Main now available, containing everything (that is, Bool
  6989 and Arith);
  6990 
  6991 
  6992 *** General ***
  6993 
  6994 * Pure: the Simplifier has been implemented properly as a derived rule
  6995 outside of the actual kernel (at last!); the overall performance
  6996 penalty in practical applications is about 50%, while reliability of
  6997 the Isabelle inference kernel has been greatly improved;
  6998 
  6999 * print modes "brackets" and "no_brackets" control output of nested =>
  7000 (types) and ==> (props); the default behaviour is "brackets";
  7001 
  7002 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7003 as assumptions as well;
  7004 
  7005 * system: support Poly/ML 4.0;
  7006 
  7007 * system: isatool install handles KDE version 1 or 2;
  7008 
  7009 
  7010 
  7011 New in Isabelle99-1 (October 2000)
  7012 ----------------------------------
  7013 
  7014 *** Overview of INCOMPATIBILITIES ***
  7015 
  7016 * HOL: simplification of natural numbers is much changed; to partly
  7017 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7018 issue the following ML commands:
  7019 
  7020   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7021   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7022 
  7023 * HOL: simplification no longer dives into case-expressions; this is
  7024 controlled by "t.weak_case_cong" for each datatype t;
  7025 
  7026 * HOL: nat_less_induct renamed to less_induct;
  7027 
  7028 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7029 fixsome to patch .thy and .ML sources automatically;
  7030 
  7031   select_equality  -> some_equality
  7032   select_eq_Ex     -> some_eq_ex
  7033   selectI2EX       -> someI2_ex
  7034   selectI2         -> someI2
  7035   selectI          -> someI
  7036   select1_equality -> some1_equality
  7037   Eps_sym_eq       -> some_sym_eq_trivial
  7038   Eps_eq           -> some_eq_trivial
  7039 
  7040 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7041 
  7042 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7043 instead);
  7044 
  7045 * HOL: the recursion equations generated by 'recdef' are now called
  7046 f.simps instead of f.rules;
  7047 
  7048 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7049 
  7050 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7051 sometimes be needed;
  7052 
  7053 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7054 
  7055 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7056 
  7057 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7058 product is now "<*>" instead of "Times"; the lexicographic product is
  7059 now "<*lex*>" instead of "**";
  7060 
  7061 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7062 of main HOL, but was unused); better use HOL's datatype package;
  7063 
  7064 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7065 the old syntax may be recovered as follows:
  7066 
  7067   syntax (symbols)
  7068     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7069       (infixl "\\<oplus>" 100)
  7070 
  7071 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7072 
  7073 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7074 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7075 internally;
  7076 
  7077 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7078 changed from A/r to A//r;
  7079 
  7080 * ZF: new treatment of arithmetic (nat & int) may break some old
  7081 proofs;
  7082 
  7083 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7084 rulify -> rule_format, elimify -> elim_format, ...);
  7085 
  7086 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7087 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7088 should have to change intro!! to intro? only); replaced "delrule" by
  7089 "rule del";
  7090 
  7091 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7092 
  7093 * Provers: strengthened force_tac by using new first_best_tac;
  7094 
  7095 * LaTeX document preparation: several changes of isabelle.sty (see
  7096 lib/texinputs);
  7097 
  7098 
  7099 *** Document preparation ***
  7100 
  7101 * formal comments (text blocks etc.) in new-style theories may now
  7102 contain antiquotations of thm/prop/term/typ/text to be presented
  7103 according to latex print mode; concrete syntax is like this:
  7104 @{term[show_types] "f(x) = a + x"};
  7105 
  7106 * isatool mkdir provides easy setup of Isabelle session directories,
  7107 including proper document sources;
  7108 
  7109 * generated LaTeX sources are now deleted after successful run
  7110 (isatool document -c); may retain a copy somewhere else via -D option
  7111 of isatool usedir;
  7112 
  7113 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7114 style files, achieving self-contained LaTeX sources and simplifying
  7115 LaTeX debugging;
  7116 
  7117 * old-style theories now produce (crude) LaTeX output as well;
  7118 
  7119 * browser info session directories are now self-contained (may be put
  7120 on WWW server seperately); improved graphs of nested sessions; removed
  7121 graph for 'all sessions';
  7122 
  7123 * several improvements in isabelle style files; \isabellestyle{it}
  7124 produces fake math mode output; \isamarkupheader is now \section by
  7125 default; see lib/texinputs/isabelle.sty etc.;
  7126 
  7127 
  7128 *** Isar ***
  7129 
  7130 * Isar/Pure: local results and corresponding term bindings are now
  7131 subject to Hindley-Milner polymorphism (similar to ML); this
  7132 accommodates incremental type-inference very nicely;
  7133 
  7134 * Isar/Pure: new derived language element 'obtain' supports
  7135 generalized existence reasoning;
  7136 
  7137 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7138 support accumulation of results, without applying any rules yet;
  7139 useful to collect intermediate results without explicit name
  7140 references, and for use with transitivity rules with more than 2
  7141 premises;
  7142 
  7143 * Isar/Pure: scalable support for case-analysis type proofs: new
  7144 'case' language element refers to local contexts symbolically, as
  7145 produced by certain proof methods; internally, case names are attached
  7146 to theorems as "tags";
  7147 
  7148 * Isar/Pure: theory command 'hide' removes declarations from
  7149 class/type/const name spaces;
  7150 
  7151 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7152 indicate potential overloading;
  7153 
  7154 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7155 
  7156 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7157 "{a,b,c}" instead of {a,b,c};
  7158 
  7159 * Isar/Pure now provides its own version of intro/elim/dest
  7160 attributes; useful for building new logics, but beware of confusion
  7161 with the version in Provers/classical;
  7162 
  7163 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7164 case name 'antecedent';
  7165 
  7166 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7167 to the current context is now done automatically);
  7168 
  7169 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7170 for definining proof methods in ML;
  7171 
  7172 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7173 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7174 most cases, one should have to change intro!! to intro? only);
  7175 replaced "delrule" by "rule del";
  7176 
  7177 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7178 'symmetric' attribute (the latter supercedes [RS sym]);
  7179 
  7180 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7181 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7182 well (including splits);
  7183 
  7184 * Isar/Provers: Simplifier and Classical methods now support all kind
  7185 of modifiers used in the past, including 'cong', 'iff', etc.
  7186 
  7187 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7188 of Simplifier and Classical reasoner);
  7189 
  7190 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7191 now support named cases; major packages (inductive, datatype, primrec,
  7192 recdef) support case names and properly name parameters;
  7193 
  7194 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7195 monotonicity conditions are extracted to be proven at end of
  7196 calculations;
  7197 
  7198 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7199 method anyway;
  7200 
  7201 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7202 split_if split_if_asm; datatype package provides theorems foo.splits =
  7203 foo.split foo.split_asm for each datatype;
  7204 
  7205 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7206 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7207 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7208 use "(cases (simplified))" method in proper proof texts);
  7209 
  7210 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7211 
  7212 * Isar: names of theorems etc. may be natural numbers as well;
  7213 
  7214 * Isar: 'pr' command: optional arguments for goals_limit and
  7215 ProofContext.prems_limit; no longer prints theory contexts, but only
  7216 proof states;
  7217 
  7218 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7219 additional print modes to be specified; e.g. "pr(latex)" will print
  7220 proof state according to the Isabelle LaTeX style;
  7221 
  7222 * Isar: improved support for emulating tactic scripts, including proof
  7223 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7224 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7225 (for HOL datatypes);
  7226 
  7227 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7228 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7229 'proof method scripts' have to be in depth-first order;
  7230 
  7231 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7232 
  7233 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7234 should instead use individual commands for printing items
  7235 (print_commands, print_methods etc.);
  7236 
  7237 * Isar: added 'nothing' --- the empty list of theorems;
  7238 
  7239 
  7240 *** HOL ***
  7241 
  7242 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7243 corresponding virtual machine and a specification of its bytecode
  7244 verifier and a lightweight bytecode verifier, including proofs of
  7245 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7246 Cornelia Pusch (see also the homepage of project Bali at
  7247 http://isabelle.in.tum.de/Bali/);
  7248 
  7249 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7250 Clemens Ballarin;
  7251 
  7252 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7253 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7254 Rasmussen;
  7255 
  7256 * HOL/Lattice: fundamental concepts of lattice theory and order
  7257 structures, including duals, properties of bounds versus algebraic
  7258 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7259 Theorem for complete lattices etc.; may also serve as a demonstration
  7260 for abstract algebraic reasoning using axiomatic type classes, and
  7261 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7262 
  7263 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7264 von Oheimb;
  7265 
  7266 * HOL/IMPP: extension of IMP with local variables and mutually
  7267 recursive procedures, by David von Oheimb;
  7268 
  7269 * HOL/Lambda: converted into new-style theory and document;
  7270 
  7271 * HOL/ex/Multiquote: example of multiple nested quotations and
  7272 anti-quotations -- basically a generalized version of de-Bruijn
  7273 representation; very useful in avoiding lifting of operations;
  7274 
  7275 * HOL/record: added general record equality rule to simpset; fixed
  7276 select-update simplification procedure to handle extended records as
  7277 well; admit "r" as field name;
  7278 
  7279 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7280 other numeric types and also as the identity of groups, rings, etc.;
  7281 
  7282 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7283 Types nat and int belong to this axclass;
  7284 
  7285 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7286    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7287    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7288   two terms #m*u and #n*u are replaced by #(m+n)*u
  7289     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7290   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7291     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7292 
  7293 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7294 powerful prover for predicate logic but knows nothing of clasets; see
  7295 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7296 
  7297 * HOL: new version of "case_tac" subsumes both boolean case split and
  7298 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7299 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7300 
  7301 * HOL: simplification no longer dives into case-expressions: only the
  7302 selector expression is simplified, but not the remaining arms; to
  7303 enable full simplification of case-expressions for datatype t, you may
  7304 remove t.weak_case_cong from the simpset, either globally (Delcongs
  7305 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  7306 
  7307 * HOL/recdef: the recursion equations generated by 'recdef' for
  7308 function 'f' are now called f.simps instead of f.rules; if all
  7309 termination conditions are proved automatically, these simplification
  7310 rules are added to the simpset, as in primrec; rules may be named
  7311 individually as well, resulting in a separate list of theorems for
  7312 each equation;
  7313 
  7314 * HOL/While is a new theory that provides a while-combinator. It
  7315 permits the definition of tail-recursive functions without the
  7316 provision of a termination measure. The latter is necessary once the
  7317 invariant proof rule for while is applied.
  7318 
  7319 * HOL: new (overloaded) notation for the set of elements below/above
  7320 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  7321 
  7322 * HOL: theorems impI, allI, ballI bound as "strip";
  7323 
  7324 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  7325 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  7326 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  7327 
  7328 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7329 
  7330 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  7331 main HOL, but was unused);
  7332 
  7333 * HOL: fewer consts declared as global (e.g. have to refer to
  7334 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  7335 
  7336 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  7337 in case of overlap with user translations (e.g. judgements over
  7338 tuples); (note that the underlying logical represenation is still
  7339 bogus);
  7340 
  7341 
  7342 *** ZF ***
  7343 
  7344 * ZF: simplification automatically cancels common terms in arithmetic
  7345 expressions over nat and int;
  7346 
  7347 * ZF: new treatment of nat to minimize type-checking: all operators
  7348 coerce their operands to a natural number using the function natify,
  7349 making the algebraic laws unconditional;
  7350 
  7351 * ZF: as above, for int: operators coerce their operands to an integer
  7352 using the function intify;
  7353 
  7354 * ZF: the integer library now contains many of the usual laws for the
  7355 orderings, including $<=, and monotonicity laws for $+ and $*;
  7356 
  7357 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  7358 simplification;
  7359 
  7360 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  7361 to the simplifier and classical reasoner simultaneously;
  7362 
  7363 
  7364 *** General ***
  7365 
  7366 * Provers: blast_tac now handles actual object-logic rules as
  7367 assumptions; note that auto_tac uses blast_tac internally as well;
  7368 
  7369 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  7370 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  7371 
  7372 * Provers: delrules now handles destruct rules as well (no longer need
  7373 explicit make_elim);
  7374 
  7375 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  7376   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7377 use instead the strong form,
  7378   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7379 in HOL, FOL and ZF the function cla_make_elim will create such rules
  7380 from destruct-rules;
  7381 
  7382 * Provers: Simplifier.easy_setup provides a fast path to basic
  7383 Simplifier setup for new object-logics;
  7384 
  7385 * Pure: AST translation rules no longer require constant head on LHS;
  7386 
  7387 * Pure: improved name spaces: ambiguous output is qualified; support
  7388 for hiding of names;
  7389 
  7390 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7391 XSYMBOL_HOME; no longer need to do manual configuration in most
  7392 situations;
  7393 
  7394 * system: compression of ML heaps images may now be controlled via -c
  7395 option of isabelle and isatool usedir (currently only observed by
  7396 Poly/ML);
  7397 
  7398 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7399 useful for remote X11);
  7400 
  7401 * system: provide TAGS file for Isabelle sources;
  7402 
  7403 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7404 order;
  7405 
  7406 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7407 timing flag supersedes proof_timing and Toplevel.trace;
  7408 
  7409 * ML: new combinators |>> and |>>> for incremental transformations
  7410 with secondary results (e.g. certain theory extensions):
  7411 
  7412 * ML: PureThy.add_defs gets additional argument to indicate potential
  7413 overloading (usually false);
  7414 
  7415 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7416 results;
  7417 
  7418 
  7419 
  7420 New in Isabelle99 (October 1999)
  7421 --------------------------------
  7422 
  7423 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7424 
  7425 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7426 are no longer simplified.  (This allows the simplifier to unfold recursive
  7427 functional programs.)  To restore the old behaviour, declare
  7428 
  7429     Delcongs [if_weak_cong];
  7430 
  7431 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  7432 complement;
  7433 
  7434 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  7435 
  7436 * HOL/datatype: mutual_induct_tac no longer exists --
  7437   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  7438 
  7439 * HOL/typedef: fixed type inference for representing set; type
  7440 arguments now have to occur explicitly on the rhs as type constraints;
  7441 
  7442 * ZF: The con_defs part of an inductive definition may no longer refer
  7443 to constants declared in the same theory;
  7444 
  7445 * HOL, ZF: the function mk_cases, generated by the inductive
  7446 definition package, has lost an argument.  To simplify its result, it
  7447 uses the default simpset instead of a supplied list of theorems.
  7448 
  7449 * HOL/List: the constructors of type list are now Nil and Cons;
  7450 
  7451 * Simplifier: the type of the infix ML functions
  7452         setSSolver addSSolver setSolver addSolver
  7453 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  7454 for packaging solvers. A solver is created via
  7455         mk_solver: string -> (thm list -> int -> tactic) -> solver
  7456 where the string argument is only a comment.
  7457 
  7458 
  7459 *** Proof tools ***
  7460 
  7461 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  7462 decision procedure for linear arithmetic. Currently it is used for
  7463 types `nat', `int', and `real' in HOL (see below); it can, should and
  7464 will be instantiated for other types and logics as well.
  7465 
  7466 * The simplifier now accepts rewrite rules with flexible heads, eg
  7467      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  7468   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  7469   matching.
  7470 
  7471 
  7472 *** General ***
  7473 
  7474 * New Isabelle/Isar subsystem provides an alternative to traditional
  7475 tactical theorem proving; together with the ProofGeneral/isar user
  7476 interface it offers an interactive environment for developing human
  7477 readable proof documents (Isar == Intelligible semi-automated
  7478 reasoning); for further information see isatool doc isar-ref,
  7479 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  7480 
  7481 * improved and simplified presentation of theories: better HTML markup
  7482 (including colors), graph views in several sizes; isatool usedir now
  7483 provides a proper interface for user theories (via -P option); actual
  7484 document preparation based on (PDF)LaTeX is available as well (for
  7485 new-style theories only); see isatool doc system for more information;
  7486 
  7487 * native support for Proof General, both for classic Isabelle and
  7488 Isabelle/Isar;
  7489 
  7490 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7491 using the graph browser tool;
  7492 
  7493 * Isabelle manuals now also available as PDF;
  7494 
  7495 * theory loader rewritten from scratch (may not be fully
  7496 bug-compatible); old loadpath variable has been replaced by show_path,
  7497 add_path, del_path, reset_path functions; new operations such as
  7498 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7499 isatool doc ref);
  7500 
  7501 * improved isatool install: option -k creates KDE application icon,
  7502 option -p DIR installs standalone binaries;
  7503 
  7504 * added ML_PLATFORM setting (useful for cross-platform installations);
  7505 more robust handling of platform specific ML images for SML/NJ;
  7506 
  7507 * the settings environment is now statically scoped, i.e. it is never
  7508 created again in sub-processes invoked from isabelle, isatool, or
  7509 Isabelle;
  7510 
  7511 * path element specification '~~' refers to '$ISABELLE_HOME';
  7512 
  7513 * in locales, the "assumes" and "defines" parts may be omitted if
  7514 empty;
  7515 
  7516 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7517 long arrows);
  7518 
  7519 * new print_mode "HTML";
  7520 
  7521 * new flag show_tags controls display of tags of theorems (which are
  7522 basically just comments that may be attached by some tools);
  7523 
  7524 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7525 mode and goal output format:
  7526 
  7527 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7528 244c244
  7529 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7530 ---
  7531 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7532 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7533 181c181
  7534 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7535 ---
  7536 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7537 
  7538 * function bind_thms stores lists of theorems (cf. bind_thm);
  7539 
  7540 * new shorthand tactics ftac, eatac, datac, fatac;
  7541 
  7542 * qed (and friends) now accept "" as result name; in that case the
  7543 theorem is not stored, but proper checks and presentation of the
  7544 result still apply;
  7545 
  7546 * theorem database now also indexes constants "Trueprop", "all",
  7547 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7548 
  7549 
  7550 *** HOL ***
  7551 
  7552 ** HOL arithmetic **
  7553 
  7554 * There are now decision procedures for linear arithmetic over nat and
  7555 int:
  7556 
  7557 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7558 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7559 are treated as atomic; subformulae not involving type `nat' or `int'
  7560 are ignored; quantified subformulae are ignored unless they are
  7561 positive universal or negative existential. The tactic has to be
  7562 invoked by hand and can be a little bit slow. In particular, the
  7563 running time is exponential in the number of occurrences of `min' and
  7564 `max', and `-' on `nat'.
  7565 
  7566 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7567 (negated) (in)equalities among the premises and the conclusion into
  7568 account (i.e. no compound formulae) and does not know about `min' and
  7569 `max', and `-' on `nat'. It is fast and is used automatically by the
  7570 simplifier.
  7571 
  7572 NB: At the moment, these decision procedures do not cope with mixed
  7573 nat/int formulae where the two parts interact, such as `m < n ==>
  7574 int(m) < int(n)'.
  7575 
  7576 * HOL/Numeral provides a generic theory of numerals (encoded
  7577 efficiently as bit strings); setup for types nat/int/real is in place;
  7578 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7579 int, existing theories and proof scripts may require a few additional
  7580 type constraints;
  7581 
  7582 * integer division and remainder can now be performed on constant
  7583 arguments;
  7584 
  7585 * many properties of integer multiplication, division and remainder
  7586 are now available;
  7587 
  7588 * An interface to the Stanford Validity Checker (SVC) is available through the
  7589 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7590 are proved automatically.  SVC must be installed separately, and its results
  7591 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7592 invocation of the underlying oracle).  For SVC see
  7593   http://verify.stanford.edu/SVC
  7594 
  7595 * IsaMakefile: the HOL-Real target now builds an actual image;
  7596 
  7597 
  7598 ** HOL misc **
  7599 
  7600 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7601 (in Isabelle/Isar) -- by Gertrud Bauer;
  7602 
  7603 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7604 analysis for assembly languages with subtypes;
  7605 
  7606 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7607 -- avoids syntactic ambiguities and treats state, transition, and
  7608 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7609 changed syntax and (many) tactics;
  7610 
  7611 * HOL/inductive: Now also handles more general introduction rules such
  7612   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7613   theorems are now maintained within the theory (maintained via the
  7614   "mono" attribute);
  7615 
  7616 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7617   (using function types) such as
  7618 
  7619   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7620 
  7621 * HOL/record: record_simproc (part of the default simpset) takes care
  7622 of selectors applied to updated records; record_split_tac is no longer
  7623 part of the default claset; update_defs may now be removed from the
  7624 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7625 
  7626   claset_ref () := claset() addSWrapper record_split_wrapper;
  7627   Delsimprocs [record_simproc]
  7628 
  7629 * HOL/typedef: fixed type inference for representing set; type
  7630 arguments now have to occur explicitly on the rhs as type constraints;
  7631 
  7632 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7633 names rather than an ML expression;
  7634 
  7635 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7636 supplied later.  Program schemes can be defined, such as
  7637     "While B C s = (if B s then While B C (C s) else s)"
  7638 where the well-founded relation can be chosen after B and C have been given.
  7639 
  7640 * HOL/List: the constructors of type list are now Nil and Cons;
  7641 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7642 course, ML tools referring to List.list.op # etc. have to be adapted;
  7643 
  7644 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7645 disabled by default; run isabelle with option -m HOL to get back to
  7646 the original Gordon/HOL-style output;
  7647 
  7648 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7649 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7650 
  7651 * HOL basic syntax simplified (more orthogonal): all variants of
  7652 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7653 Eps operator is provided as well: "SOME x. P[x]";
  7654 
  7655 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7656 
  7657 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7658 thus available for user theories;
  7659 
  7660 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7661 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7662 time;
  7663 
  7664 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7665 several times and then mp;
  7666 
  7667 
  7668 *** LK ***
  7669 
  7670 * the notation <<...>> is now available as a notation for sequences of
  7671 formulas;
  7672 
  7673 * the simplifier is now installed
  7674 
  7675 * the axiom system has been generalized (thanks to Soren Heilmann)
  7676 
  7677 * the classical reasoner now has a default rule database
  7678 
  7679 
  7680 *** ZF ***
  7681 
  7682 * new primrec section allows primitive recursive functions to be given
  7683 directly (as in HOL) over datatypes and the natural numbers;
  7684 
  7685 * new tactics induct_tac and exhaust_tac for induction (or case
  7686 analysis) over datatypes and the natural numbers;
  7687 
  7688 * the datatype declaration of type T now defines the recursor T_rec;
  7689 
  7690 * simplification automatically does freeness reasoning for datatype
  7691 constructors;
  7692 
  7693 * automatic type-inference, with AddTCs command to insert new
  7694 type-checking rules;
  7695 
  7696 * datatype introduction rules are now added as Safe Introduction rules
  7697 to the claset;
  7698 
  7699 * the syntax "if P then x else y" is now available in addition to
  7700 if(P,x,y);
  7701 
  7702 
  7703 *** Internal programming interfaces ***
  7704 
  7705 * tuned simplifier trace output; new flag debug_simp;
  7706 
  7707 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7708 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7709 
  7710 * AxClass.axclass_tac lost the theory argument;
  7711 
  7712 * tuned current_goals_markers semantics: begin / end goal avoids
  7713 printing empty lines;
  7714 
  7715 * removed prs and prs_fn hook, which was broken because it did not
  7716 include \n in its semantics, forcing writeln to add one
  7717 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7718 string -> unit if you really want to output text without newline;
  7719 
  7720 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7721 plain output, interface builders may have to enable 'isabelle_font'
  7722 mode to get Isabelle font glyphs as before;
  7723 
  7724 * refined token_translation interface; INCOMPATIBILITY: output length
  7725 now of type real instead of int;
  7726 
  7727 * theory loader actions may be traced via new ThyInfo.add_hook
  7728 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7729 your own database of information attached to *whole* theories -- as
  7730 opposed to intra-theory data slots offered via TheoryDataFun;
  7731 
  7732 * proper handling of dangling sort hypotheses (at last!);
  7733 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7734 extra sort hypotheses that can be witnessed from the type signature;
  7735 the force_strip_shyps flag is gone, any remaining shyps are simply
  7736 left in the theorem (with a warning issued by strip_shyps_warning);
  7737 
  7738 
  7739 
  7740 New in Isabelle98-1 (October 1998)
  7741 ----------------------------------
  7742 
  7743 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7744 
  7745 * several changes of automated proof tools;
  7746 
  7747 * HOL: major changes to the inductive and datatype packages, including
  7748 some minor incompatibilities of theory syntax;
  7749 
  7750 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7751 called `inj_on';
  7752 
  7753 * HOL: removed duplicate thms in Arith:
  7754   less_imp_add_less  should be replaced by  trans_less_add1
  7755   le_imp_add_le      should be replaced by  trans_le_add1
  7756 
  7757 * HOL: unary minus is now overloaded (new type constraints may be
  7758 required);
  7759 
  7760 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7761 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7762 now taken as an integer constant.
  7763 
  7764 * Pure: ML function 'theory_of' renamed to 'theory';
  7765 
  7766 
  7767 *** Proof tools ***
  7768 
  7769 * Simplifier:
  7770   1. Asm_full_simp_tac is now more aggressive.
  7771      1. It will sometimes reorient premises if that increases their power to
  7772         simplify.
  7773      2. It does no longer proceed strictly from left to right but may also
  7774         rotate premises to achieve further simplification.
  7775      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7776      old Asm_full_simp_tac in that it does not rotate premises.
  7777   2. The simplifier now knows a little bit about nat-arithmetic.
  7778 
  7779 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7780 allows for selected deletion of wrappers, by introduction of names for
  7781 wrapper functionals.  This implies that addbefore, addSbefore,
  7782 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7783 and that adding two tactics with the same name overwrites the first
  7784 one (emitting a warning).
  7785   type wrapper = (int -> tactic) -> (int -> tactic)
  7786   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7787   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7788   delWrapper, delSWrapper: claset *  string            -> claset
  7789   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7790 
  7791 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7792 semantics; addbefore now affects only the unsafe part of step_tac
  7793 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7794 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7795 by Force_tac;
  7796 
  7797 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7798 compWrapper; added safe wrapper (and access functions for it);
  7799 
  7800 * HOL/split_all_tac is now much faster and fails if there is nothing
  7801 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7802 and the names of the automatically generated variables have changed.
  7803 split_all_tac has moved within claset() from unsafe wrappers to safe
  7804 wrappers, which means that !!-bound variables are split much more
  7805 aggressively, and safe_tac and clarify_tac now split such variables.
  7806 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7807 Note: the same holds for record_split_tac, which does the job of
  7808 split_all_tac for record fields.
  7809 
  7810 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7811 permanently to the default simpset using Addsplits just like
  7812 Addsimps. They can be removed via Delsplits just like
  7813 Delsimps. Lower-case versions are also available.
  7814 
  7815 * HOL/Simplifier: The rule split_if is now part of the default
  7816 simpset. This means that the simplifier will eliminate all occurrences
  7817 of if-then-else in the conclusion of a goal. To prevent this, you can
  7818 either remove split_if completely from the default simpset by
  7819 `Delsplits [split_if]' or remove it in a specific call of the
  7820 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7821 other case splitting rules to/from the default simpset: every datatype
  7822 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7823 t is the name of the datatype).
  7824 
  7825 * Classical reasoner / Simplifier combination: new force_tac (and
  7826 derivatives Force_tac, force) combines rewriting and classical
  7827 reasoning (and whatever other tools) similarly to auto_tac, but is
  7828 aimed to solve the given subgoal completely.
  7829 
  7830 
  7831 *** General ***
  7832 
  7833 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7834 and `goalw': the theory is no longer needed as an explicit argument -
  7835 the current theory context is used; assumptions are no longer returned
  7836 at the ML-level unless one of them starts with ==> or !!; it is
  7837 recommended to convert to these new commands using isatool fixgoal
  7838 (backup your sources first!);
  7839 
  7840 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7841 the current theory context, and 'theory' to lookup stored theories;
  7842 
  7843 * new theory section 'locale' for declaring constants, assumptions and
  7844 definitions that have local scope;
  7845 
  7846 * new theory section 'nonterminals' for purely syntactic types;
  7847 
  7848 * new theory section 'setup' for generic ML setup functions
  7849 (e.g. package initialization);
  7850 
  7851 * the distribution now includes Isabelle icons: see
  7852 lib/logo/isabelle-{small,tiny}.xpm;
  7853 
  7854 * isatool install - install binaries with absolute references to
  7855 ISABELLE_HOME/bin;
  7856 
  7857 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7858 
  7859 * print mode 'emacs' reserved for Isamode;
  7860 
  7861 * support multiple print (ast) translations per constant name;
  7862 
  7863 * theorems involving oracles are now printed with a suffixed [!];
  7864 
  7865 
  7866 *** HOL ***
  7867 
  7868 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7869 
  7870 * HOL/inductive package reorganized and improved: now supports mutual
  7871 definitions such as
  7872 
  7873   inductive EVEN ODD
  7874     intrs
  7875       null "0 : EVEN"
  7876       oddI "n : EVEN ==> Suc n : ODD"
  7877       evenI "n : ODD ==> Suc n : EVEN"
  7878 
  7879 new theorem list "elims" contains an elimination rule for each of the
  7880 recursive sets; inductive definitions now handle disjunctive premises
  7881 correctly (also ZF);
  7882 
  7883 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7884 "mutual_induct" no longer exists - the induction rule is always
  7885 contained in "induct";
  7886 
  7887 
  7888 * HOL/datatype package re-implemented and greatly improved: now
  7889 supports mutually recursive datatypes such as
  7890 
  7891   datatype
  7892     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7893             | SUM ('a aexp) ('a aexp)
  7894             | DIFF ('a aexp) ('a aexp)
  7895             | NUM 'a
  7896   and
  7897     'a bexp = LESS ('a aexp) ('a aexp)
  7898             | AND ('a bexp) ('a bexp)
  7899             | OR ('a bexp) ('a bexp)
  7900 
  7901 as well as indirectly recursive datatypes such as
  7902 
  7903   datatype
  7904     ('a, 'b) term = Var 'a
  7905                   | App 'b ((('a, 'b) term) list)
  7906 
  7907 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7908 induction on mutually / indirectly recursive datatypes.
  7909 
  7910 Primrec equations are now stored in theory and can be accessed via
  7911 <function_name>.simps.
  7912 
  7913 INCOMPATIBILITIES:
  7914 
  7915   - Theories using datatypes must now have theory Datatype as an
  7916     ancestor.
  7917   - The specific <typename>.induct_tac no longer exists - use the
  7918     generic induct_tac instead.
  7919   - natE has been renamed to nat.exhaust - use exhaust_tac
  7920     instead of res_inst_tac ... natE. Note that the variable
  7921     names in nat.exhaust differ from the names in natE, this
  7922     may cause some "fragile" proofs to fail.
  7923   - The theorems split_<typename>_case and split_<typename>_case_asm
  7924     have been renamed to <typename>.split and <typename>.split_asm.
  7925   - Since default sorts of type variables are now handled correctly,
  7926     some datatype definitions may have to be annotated with explicit
  7927     sort constraints.
  7928   - Primrec definitions no longer require function name and type
  7929     of recursive argument.
  7930 
  7931 Consider using isatool fixdatatype to adapt your theories and proof
  7932 scripts to the new package (backup your sources first!).
  7933 
  7934 
  7935 * HOL/record package: considerably improved implementation; now
  7936 includes concrete syntax for record types, terms, updates; theorems
  7937 for surjective pairing and splitting !!-bound record variables; proof
  7938 support is as follows:
  7939 
  7940   1) standard conversions (selectors or updates applied to record
  7941 constructor terms) are part of the standard simpset;
  7942 
  7943   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7944 made part of standard simpset and claset via addIffs;
  7945 
  7946   3) a tactic for record field splitting (record_split_tac) is part of
  7947 the standard claset (addSWrapper);
  7948 
  7949 To get a better idea about these rules you may retrieve them via
  7950 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7951 the name of your record type.
  7952 
  7953 The split tactic 3) conceptually simplifies by the following rule:
  7954 
  7955   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7956 
  7957 Thus any record variable that is bound by meta-all will automatically
  7958 blow up into some record constructor term, consequently the
  7959 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7960 solve record problems automatically.
  7961 
  7962 
  7963 * reorganized the main HOL image: HOL/Integ and String loaded by
  7964 default; theory Main includes everything;
  7965 
  7966 * automatic simplification of integer sums and comparisons, using cancellation;
  7967 
  7968 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7969 
  7970 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7971 
  7972 * many new identities for unions, intersections, set difference, etc.;
  7973 
  7974 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7975 called split_if, split_split, split_sum_case and split_nat_case (to go
  7976 with add/delsplits);
  7977 
  7978 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7979 (?x::unit) = (); this is made part of the default simpset, which COULD
  7980 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7981 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7982 unit_abs_eta_conv is added in order to counter the effect of
  7983 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7984 %u.f();
  7985 
  7986 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7987 makes more sense);
  7988 
  7989 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7990   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7991   disjointness reasoning but breaking a few old proofs.
  7992 
  7993 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7994 to 'converse' from 'inverse' (for compatibility with ZF and some
  7995 literature);
  7996 
  7997 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7998 the well-founded relation;
  7999 
  8000 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8001     Compl A.  The "Compl" syntax remains available as input syntax for this
  8002     release ONLY.
  8003 
  8004 * HOL/Update: new theory of function updates:
  8005     f(a:=b) == %x. if x=a then b else f x
  8006 may also be iterated as in f(a:=b,c:=d,...);
  8007 
  8008 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8009 
  8010 * HOL/List:
  8011   - new function list_update written xs[i:=v] that updates the i-th
  8012     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8013   - new function `upt' written [i..j(] which generates the list
  8014     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8015     bound write [i..j], which is a shorthand for [i..j+1(].
  8016   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8017 
  8018 * HOL/Arith:
  8019   - removed 'pred' (predecessor) function;
  8020   - generalized some theorems about n-1;
  8021   - many new laws about "div" and "mod";
  8022   - new laws about greatest common divisors (see theory ex/Primes);
  8023 
  8024 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8025 instead of "inverse";
  8026 
  8027 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8028   of the multiset ordering;
  8029 
  8030 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8031   (not included by default);
  8032 
  8033 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8034 
  8035 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8036   programs, i.e. different program variables may have different types.
  8037 
  8038 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8039   [previously, this check worked only if the rewrite rule was unconditional]
  8040   Now rew can involve either definitions or equalities (either == or =).
  8041 
  8042 
  8043 *** ZF ***
  8044 
  8045 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8046   only the theorems proved on ZF.ML;
  8047 
  8048 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8049   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8050   disjointness reasoning but breaking a few old proofs.
  8051 
  8052 * ZF/Update: new theory of function updates
  8053     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8054   may also be iterated as in f(a:=b,c:=d,...);
  8055 
  8056 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8057 
  8058 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8059   [previously, this check worked only if the rewrite rule was unconditional]
  8060   Now rew can involve either definitions or equalities (either == or =).
  8061 
  8062 * case_tac provided for compatibility with HOL
  8063     (like the old excluded_middle_tac, but with subgoals swapped)
  8064 
  8065 
  8066 *** Internal programming interfaces ***
  8067 
  8068 * Pure: several new basic modules made available for general use, see
  8069 also src/Pure/README;
  8070 
  8071 * improved the theory data mechanism to support encapsulation (data
  8072 kind name replaced by private Object.kind, acting as authorization
  8073 key); new type-safe user interface via functor TheoryDataFun; generic
  8074 print_data function becomes basically useless;
  8075 
  8076 * removed global_names compatibility flag -- all theory declarations
  8077 are qualified by default;
  8078 
  8079 * module Pure/Syntax now offers quote / antiquote translation
  8080 functions (useful for Hoare logic etc. with implicit dependencies);
  8081 see HOL/ex/Antiquote for an example use;
  8082 
  8083 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8084 cterm -> thm;
  8085 
  8086 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8087 subgoal;
  8088 
  8089 * Display.print_goals function moved to Locale.print_goals;
  8090 
  8091 * standard print function for goals supports current_goals_markers
  8092 variable for marking begin of proof, end of proof, start of goal; the
  8093 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8094 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8095 for example;
  8096 
  8097 
  8098 
  8099 New in Isabelle98 (January 1998)
  8100 --------------------------------
  8101 
  8102 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8103 
  8104 * changed lexical syntax of terms / types: dots made part of long
  8105 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8106 
  8107 * simpset (and claset) reference variable replaced by functions
  8108 simpset / simpset_ref;
  8109 
  8110 * no longer supports theory aliases (via merge) and non-trivial
  8111 implicit merge of thms' signatures;
  8112 
  8113 * most internal names of constants changed due to qualified names;
  8114 
  8115 * changed Pure/Sequence interface (see Pure/seq.ML);
  8116 
  8117 
  8118 *** General Changes ***
  8119 
  8120 * hierachically structured name spaces (for consts, types, axms, thms
  8121 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8122 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8123 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8124 long_names for fully qualified output names; NOTE: ML programs
  8125 (special tactics, packages etc.) referring to internal names may have
  8126 to be adapted to cope with fully qualified names; in case of severe
  8127 backward campatibility problems try setting 'global_names' at compile
  8128 time to have enrything declared within a flat name space; one may also
  8129 fine tune name declarations in theories via the 'global' and 'local'
  8130 section;
  8131 
  8132 * reimplemented the implicit simpset and claset using the new anytype
  8133 data filed in signatures; references simpset:simpset ref etc. are
  8134 replaced by functions simpset:unit->simpset and
  8135 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8136 to patch your ML files accordingly;
  8137 
  8138 * HTML output now includes theory graph data for display with Java
  8139 applet or isatool browser; data generated automatically via isatool
  8140 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8141 
  8142 * defs may now be conditional; improved rewrite_goals_tac to handle
  8143 conditional equations;
  8144 
  8145 * defs now admits additional type arguments, using TYPE('a) syntax;
  8146 
  8147 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8148 creates a new theory node; implicit merge of thms' signatures is
  8149 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8150 transfer:theory->thm->thm in (rare) cases;
  8151 
  8152 * improved handling of draft signatures / theories; draft thms (and
  8153 ctyps, cterms) are automatically promoted to real ones;
  8154 
  8155 * slightly changed interfaces for oracles: admit many per theory, named
  8156 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8157 
  8158 * print_goals: optional output of const types (set show_consts and
  8159 show_types);
  8160 
  8161 * improved output of warnings (###) and errors (***);
  8162 
  8163 * subgoal_tac displays a warning if the new subgoal has type variables;
  8164 
  8165 * removed old README and Makefiles;
  8166 
  8167 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8168 
  8169 * removed obsolete init_pps and init_database;
  8170 
  8171 * deleted the obsolete tactical STATE, which was declared by
  8172     fun STATE tacfun st = tacfun st st;
  8173 
  8174 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8175 (which abbreviates $HOME);
  8176 
  8177 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8178 use isatool fixseq to adapt your ML programs (this works for fully
  8179 qualified references to the Sequence structure only!);
  8180 
  8181 * use_thy no longer requires writable current directory; it always
  8182 reloads .ML *and* .thy file, if either one is out of date;
  8183 
  8184 
  8185 *** Classical Reasoner ***
  8186 
  8187 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8188 tactics that use classical reasoning to simplify a subgoal without
  8189 splitting it into several subgoals;
  8190 
  8191 * Safe_tac: like safe_tac but uses the default claset;
  8192 
  8193 
  8194 *** Simplifier ***
  8195 
  8196 * added simplification meta rules:
  8197     (asm_)(full_)simplify: simpset -> thm -> thm;
  8198 
  8199 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8200 logics (again);
  8201 
  8202 * added prems argument to simplification procedures;
  8203 
  8204 * HOL, FOL, ZF: added infix function `addsplits':
  8205   instead of `<simpset> setloop (split_tac <thms>)'
  8206   you can simply write `<simpset> addsplits <thms>'
  8207 
  8208 
  8209 *** Syntax ***
  8210 
  8211 * TYPE('a) syntax for type reflection terms;
  8212 
  8213 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8214 
  8215 * pretty printer: changed order of mixfix annotation preference (again!);
  8216 
  8217 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8218 
  8219 
  8220 *** HOL ***
  8221 
  8222 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8223   with `addloop' of the simplifier to faciliate case splitting in premises.
  8224 
  8225 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8226 
  8227 * HOL/Auth: new protocol proofs including some for the Internet
  8228   protocol TLS;
  8229 
  8230 * HOL/Map: new theory of `maps' a la VDM;
  8231 
  8232 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8233 cancelling out common nat summands from =, <, <= (in)equalities, or
  8234 differences; simplification procedures nat_cancel_factor for
  8235 cancelling common factor from =, <, <= (in)equalities over natural
  8236 sums; nat_cancel contains both kinds of procedures, it is installed by
  8237 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8238 
  8239 * HOL/simplifier: terms of the form
  8240   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8241   are rewritten to
  8242   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8243   and those of the form
  8244   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8245   are rewritten to
  8246   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8247 
  8248 * HOL/datatype
  8249   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8250 
  8251   P(t_case f1 ... fn x) =
  8252      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8253         ...
  8254        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8255      )
  8256 
  8257   and a theorem `split_t_case_asm' of the form
  8258 
  8259   P(t_case f1 ... fn x) =
  8260     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8261         ...
  8262        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8263      )
  8264   which can be added to a simpset via `addsplits'. The existing theorems
  8265   expand_list_case and expand_option_case have been renamed to
  8266   split_list_case and split_option_case.
  8267 
  8268 * HOL/Arithmetic:
  8269   - `pred n' is automatically converted to `n-1'.
  8270     Users are strongly encouraged not to use `pred' any longer,
  8271     because it will disappear altogether at some point.
  8272   - Users are strongly encouraged to write "0 < n" rather than
  8273     "n ~= 0". Theorems and proof tools have been modified towards this
  8274     `standard'.
  8275 
  8276 * HOL/Lists:
  8277   the function "set_of_list" has been renamed "set" (and its theorems too);
  8278   the function "nth" now takes its arguments in the reverse order and
  8279   has acquired the infix notation "!" as in "xs!n".
  8280 
  8281 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8282 
  8283 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8284   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8285 
  8286 * HOL/record: extensible records with schematic structural subtyping
  8287 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8288 still lacks various theorems and concrete record syntax;
  8289 
  8290 
  8291 *** HOLCF ***
  8292 
  8293 * removed "axioms" and "generated by" sections;
  8294 
  8295 * replaced "ops" section by extended "consts" section, which is capable of
  8296   handling the continuous function space "->" directly;
  8297 
  8298 * domain package:
  8299   . proves theorems immediately and stores them in the theory,
  8300   . creates hierachical name space,
  8301   . now uses normal mixfix annotations (instead of cinfix...),
  8302   . minor changes to some names and values (for consistency),
  8303   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  8304   . separator between mutual domain defs: changed "," to "and",
  8305   . improved handling of sort constraints;  now they have to
  8306     appear on the left-hand side of the equations only;
  8307 
  8308 * fixed LAM <x,y,zs>.b syntax;
  8309 
  8310 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  8311 adm (%x. P (t x)), where P is chainfinite and t continuous;
  8312 
  8313 
  8314 *** FOL and ZF ***
  8315 
  8316 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8317   with `addloop' of the simplifier to faciliate case splitting in premises.
  8318 
  8319 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  8320 in HOL, they strip ALL and --> from proved theorems;
  8321 
  8322 
  8323 
  8324 New in Isabelle94-8 (May 1997)
  8325 ------------------------------
  8326 
  8327 *** General Changes ***
  8328 
  8329 * new utilities to build / run / maintain Isabelle etc. (in parts
  8330 still somewhat experimental); old Makefiles etc. still functional;
  8331 
  8332 * new 'Isabelle System Manual';
  8333 
  8334 * INSTALL text, together with ./configure and ./build scripts;
  8335 
  8336 * reimplemented type inference for greater efficiency, better error
  8337 messages and clean internal interface;
  8338 
  8339 * prlim command for dealing with lots of subgoals (an easier way of
  8340 setting goals_limit);
  8341 
  8342 
  8343 *** Syntax ***
  8344 
  8345 * supports alternative (named) syntax tables (parser and pretty
  8346 printer); internal interface is provided by add_modesyntax(_i);
  8347 
  8348 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  8349 be used in conjunction with the Isabelle symbol font; uses the
  8350 "symbols" syntax table;
  8351 
  8352 * added token_translation interface (may translate name tokens in
  8353 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  8354 the current print_mode); IMPORTANT: user print translation functions
  8355 are responsible for marking newly introduced bounds
  8356 (Syntax.mark_boundT);
  8357 
  8358 * token translations for modes "xterm" and "xterm_color" that display
  8359 names in bold, underline etc. or colors (which requires a color
  8360 version of xterm);
  8361 
  8362 * infixes may now be declared with names independent of their syntax;
  8363 
  8364 * added typed_print_translation (like print_translation, but may
  8365 access type of constant);
  8366 
  8367 
  8368 *** Classical Reasoner ***
  8369 
  8370 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  8371 some limitations.  Blast_tac...
  8372   + ignores addss, addbefore, addafter; this restriction is intrinsic
  8373   + ignores elimination rules that don't have the correct format
  8374         (the conclusion MUST be a formula variable)
  8375   + ignores types, which can make HOL proofs fail
  8376   + rules must not require higher-order unification, e.g. apply_type in ZF
  8377     [message "Function Var's argument not a bound variable" relates to this]
  8378   + its proof strategy is more general but can actually be slower
  8379 
  8380 * substitution with equality assumptions no longer permutes other
  8381 assumptions;
  8382 
  8383 * minor changes in semantics of addafter (now called addaltern); renamed
  8384 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8385 (and access functions for it);
  8386 
  8387 * improved combination of classical reasoner and simplifier:
  8388   + functions for handling clasimpsets
  8389   + improvement of addss: now the simplifier is called _after_ the
  8390     safe steps.
  8391   + safe variant of addss called addSss: uses safe simplifications
  8392     _during_ the safe steps. It is more complete as it allows multiple
  8393     instantiations of unknowns (e.g. with slow_tac).
  8394 
  8395 *** Simplifier ***
  8396 
  8397 * added interface for simplification procedures (functions that
  8398 produce *proven* rewrite rules on the fly, depending on current
  8399 redex);
  8400 
  8401 * ordering on terms as parameter (used for ordered rewriting);
  8402 
  8403 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8404 
  8405 * the solver is now split into a safe and an unsafe part.
  8406 This should be invisible for the normal user, except that the
  8407 functions setsolver and addsolver have been renamed to setSolver and
  8408 addSolver; added safe_asm_full_simp_tac;
  8409 
  8410 
  8411 *** HOL ***
  8412 
  8413 * a generic induction tactic `induct_tac' which works for all datatypes and
  8414 also for type `nat';
  8415 
  8416 * a generic case distinction tactic `exhaust_tac' which works for all
  8417 datatypes and also for type `nat';
  8418 
  8419 * each datatype comes with a function `size';
  8420 
  8421 * patterns in case expressions allow tuple patterns as arguments to
  8422 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8423 
  8424 * primrec now also works with type nat;
  8425 
  8426 * recdef: a new declaration form, allows general recursive functions to be
  8427 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  8428 
  8429 * the constant for negation has been renamed from "not" to "Not" to
  8430 harmonize with FOL, ZF, LK, etc.;
  8431 
  8432 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  8433 infinite lists;
  8434 
  8435 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  8436 
  8437 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  8438 problems in commutative rings, using axiomatic type classes for + and *;
  8439 
  8440 * more examples in HOL/MiniML and HOL/Auth;
  8441 
  8442 * more default rewrite rules for quantifiers, union/intersection;
  8443 
  8444 * a new constant `arbitrary == @x.False';
  8445 
  8446 * HOLCF/IOA replaces old HOL/IOA;
  8447 
  8448 * HOLCF changes: derived all rules and arities
  8449   + axiomatic type classes instead of classes
  8450   + typedef instead of faking type definitions
  8451   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8452   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8453   + eliminated the types void, one, tr
  8454   + use unit lift and bool lift (with translations) instead of one and tr
  8455   + eliminated blift from Lift3.thy (use Def instead of blift)
  8456   all eliminated rules are derived as theorems --> no visible changes ;
  8457 
  8458 
  8459 *** ZF ***
  8460 
  8461 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  8462 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  8463 as ZF_cs addSIs [equalityI];
  8464 
  8465 
  8466 
  8467 New in Isabelle94-7 (November 96)
  8468 ---------------------------------
  8469 
  8470 * allowing negative levels (as offsets) in prlev and choplev;
  8471 
  8472 * super-linear speedup for large simplifications;
  8473 
  8474 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  8475 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  8476 FAIL); can suppress it using the command Delsimps (ex_simps @
  8477 all_simps); De Morgan laws are also now included, by default;
  8478 
  8479 * improved printing of ==>  :  ~:
  8480 
  8481 * new object-logic "Sequents" adds linear logic, while replacing LK
  8482 and Modal (thanks to Sara Kalvala);
  8483 
  8484 * HOL/Auth: correctness proofs for authentication protocols;
  8485 
  8486 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8487 examples on HOL/Auth);
  8488 
  8489 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8490 the rewriter and classical reasoner simultaneously;
  8491 
  8492 * function uresult no longer returns theorems in "standard" format;
  8493 regain previous version by: val uresult = standard o uresult;
  8494 
  8495 
  8496 
  8497 New in Isabelle94-6
  8498 -------------------
  8499 
  8500 * oracles -- these establish an interface between Isabelle and trusted
  8501 external reasoners, which may deliver results as theorems;
  8502 
  8503 * proof objects (in particular record all uses of oracles);
  8504 
  8505 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8506 
  8507 * "constdefs" section in theory files;
  8508 
  8509 * "primrec" section (HOL) no longer requires names;
  8510 
  8511 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8512 
  8513 
  8514 
  8515 New in Isabelle94-5
  8516 -------------------
  8517 
  8518 * reduced space requirements;
  8519 
  8520 * automatic HTML generation from theories;
  8521 
  8522 * theory files no longer require "..." (quotes) around most types;
  8523 
  8524 * new examples, including two proofs of the Church-Rosser theorem;
  8525 
  8526 * non-curried (1994) version of HOL is no longer distributed;
  8527 
  8528 
  8529 
  8530 New in Isabelle94-4
  8531 -------------------
  8532 
  8533 * greatly reduced space requirements;
  8534 
  8535 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8536 
  8537 * searchable theorem database (see the section "Retrieving theorems" on
  8538 page 8 of the Reference Manual);
  8539 
  8540 * new examples, including Grabczewski's monumental case study of the
  8541 Axiom of Choice;
  8542 
  8543 * The previous version of HOL renamed to Old_HOL;
  8544 
  8545 * The new version of HOL (previously called CHOL) uses a curried syntax
  8546 for functions.  Application looks like f a b instead of f(a,b);
  8547 
  8548 * Mutually recursive inductive definitions finally work in HOL;
  8549 
  8550 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8551 translates to the operator "split";
  8552 
  8553 
  8554 
  8555 New in Isabelle94-3
  8556 -------------------
  8557 
  8558 * new infix operator, addss, allowing the classical reasoner to
  8559 perform simplification at each step of its search.  Example:
  8560         fast_tac (cs addss ss)
  8561 
  8562 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8563 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8564 look like (a,b) instead of <a,b>;
  8565 
  8566 * PLEASE NOTE: CHOL will eventually replace HOL!
  8567 
  8568 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8569 It translates to the operator "split".  A new theory of integers is available;
  8570 
  8571 * In ZF, integer numerals now denote two's-complement binary integers.
  8572 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8573 
  8574 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8575 of the Axiom of Choice;
  8576 
  8577 
  8578 
  8579 New in Isabelle94-2
  8580 -------------------
  8581 
  8582 * Significantly faster resolution;
  8583 
  8584 * the different sections in a .thy file can now be mixed and repeated
  8585 freely;
  8586 
  8587 * Database of theorems for FOL, HOL and ZF.  New
  8588 commands including qed, qed_goal and bind_thm store theorems in the database.
  8589 
  8590 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8591 a given theory (thms_of), or find out what theory a theorem was proved in
  8592 (theory_of_thm);
  8593 
  8594 * Bugs fixed in the inductive definition and datatype packages;
  8595 
  8596 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8597 and HOL_dup_cs obsolete;
  8598 
  8599 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8600 have been removed;
  8601 
  8602 * Simpler definition of function space in ZF;
  8603 
  8604 * new results about cardinal and ordinal arithmetic in ZF;
  8605 
  8606 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8607 types;
  8608 
  8609 :mode=text:wrap=hard:maxLineLen=72: