NEWS
author blanchet
Wed Sep 07 13:50:17 2011 +0200 (2011-09-07)
changeset 44784 c9a081ef441d
parent 44777 1afb48f872ae
child 44800 0472f2367efb
child 44822 2690b6de5021
permissions -rw-r--r--
tuning
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
    10 "isabelle jedit" 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 identified by content via SHA1
    38 digests.  Discontinued former path/modtime identification and optional
    39 ISABELLE_FILE_IDENT plugin scripts.
    40 
    41 * Parallelization of nested Isar proofs is subject to
    42 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    43 usedir option -Q.
    44 
    45 * Discontinued support for Poly/ML 5.2, which was the last version
    46 without proper multithreading and TimeLimit implementation.
    47 
    48 * Discontinued old lib/scripts/polyml-platform, which has been
    49 obsolete since Isabelle2009-2.
    50 
    51 * Theory loader: source files are exclusively located via the master
    52 directory of each theory node (where the .thy file itself resides).
    53 The global load path (such as src/HOL/Library) has been discontinued.
    54 Note that the path element ~~ may be used to reference theories in the
    55 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    56 INCOMPATIBILITY.
    57 
    58 * Various optional external tools are referenced more robustly and
    59 uniformly by explicit Isabelle settings as follows:
    60 
    61   ISABELLE_CSDP   (formerly CSDP_EXE)
    62   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    63   ISABELLE_OCAML  (formerly EXEC_OCAML)
    64   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    65   ISABELLE_YAP    (formerly EXEC_YAP)
    66 
    67 Note that automated detection from the file-system or search path has
    68 been discontinued.  INCOMPATIBILITY.
    69 
    70 * Name space: former unsynchronized references are now proper
    71 configuration options, with more conventional names:
    72 
    73   long_names   ~> names_long
    74   short_names  ~> names_short
    75   unique_names ~> names_unique
    76 
    77 Minor INCOMPATIBILITY, need to declare options in context like this:
    78 
    79   declare [[names_unique = false]]
    80 
    81 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    82 that the result needs to be unique, which means fact specifications
    83 may have to be refined after enriching a proof context.
    84 
    85 * Isabelle/Isar reference manual provides more formal references in
    86 syntax diagrams.
    87 
    88 * Attribute case_names has been refined: the assumptions in each case can
    89 be named now by following the case name with [name1 name2 ...].
    90 
    91 
    92 *** HOL ***
    93 
    94 * Classes bot and top require underlying partial order rather than preorder:
    95 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    96 
    97 * Class complete_lattice: generalized a couple of lemmas from sets;
    98 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    99 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
   100 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
   101 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def, Sup_fun_def,
   102 Inf_apply, Sup_apply.
   103 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
   104 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
   105 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union, UNION_eq_Union_image,
   106 Union_def, UN_singleton, UN_eq have been discarded.
   107 More consistent and less misunderstandable names:
   108   INFI_def ~> INF_def
   109   SUPR_def ~> SUP_def
   110   INF_leI ~> INF_lower
   111   INF_leI2 ~> INF_lower2
   112   le_INFI ~> INF_greatest
   113   le_SUPI ~> SUP_upper
   114   le_SUPI2 ~> SUP_upper2
   115   SUP_leI ~> SUP_least
   116   INFI_bool_eq ~> INF_bool_eq
   117   SUPR_bool_eq ~> SUP_bool_eq
   118   INFI_apply ~> INF_apply
   119   SUPR_apply ~> SUP_apply
   120   INTER_def ~> INTER_eq
   121   UNION_def ~> UNION_eq
   122 
   123 INCOMPATIBILITY.
   124 
   125 * Theorem collections ball_simps and bex_simps do not contain theorems referring
   126 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
   127 INCOMPATIBILITY.
   128 
   129 * Archimedean_Field.thy:
   130     floor now is defined as parameter of a separate type class floor_ceiling.
   131  
   132 * Finite_Set.thy: more coherent development of fold_set locales:
   133 
   134     locale fun_left_comm ~> locale comp_fun_commute
   135     locale fun_left_comm_idem ~> locale comp_fun_idem
   136     
   137 Both use point-free characterisation; interpretation proofs may need adjustment.
   138 INCOMPATIBILITY.
   139 
   140 * Code generation:
   141   - theory Library/Code_Char_ord provides native ordering of characters
   142     in the target language.
   143   - commands code_module and code_library are legacy, use export_code instead. 
   144   - method evaluation is legacy, use method eval instead.
   145   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   146     line in your theory:
   147       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   148  
   149 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   150 
   151 * Nitpick:
   152   - Added "need" and "total_consts" options.
   153   - Reintroduced "show_skolems" option by popular demand.
   154   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   155     INCOMPATIBILITY.
   156 
   157 * Sledgehammer:
   158   - sledgehammer available_provers ~> sledgehammer supported_provers.
   159     INCOMPATIBILITY.
   160   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   161     TPTP problems (TFF).
   162   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   163     and "max_new_mono_instances" options.
   164   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   165     Proof General menu item. INCOMPATIBILITY.
   166 
   167 * Metis:
   168   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   169   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   170 
   171 * "try":
   172   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   173     options. INCOMPATIBILITY.
   174   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   175     "sledgehammer", "quickcheck", and "nitpick".
   176 
   177 * Quickcheck:
   178   - Added "eval" option to evaluate terms for the found counterexample
   179     (currently only supported by the default (exhaustive) tester)
   180   - Added post-processing of terms to obtain readable counterexamples
   181     (currently only supported by the default (exhaustive) tester)
   182   - New counterexample generator quickcheck[narrowing] enables
   183     narrowing-based testing.
   184     It requires that the Glasgow Haskell compiler is installed and
   185     its location is known to Isabelle with the environment variable
   186     ISABELLE_GHC.
   187   - Removed quickcheck tester "SML" based on the SML code generator
   188     from HOL-Library
   189 
   190 * Function package: discontinued option "tailrec".
   191 INCOMPATIBILITY. Use partial_function instead.
   192 
   193 * HOL-Probability:
   194   - Caratheodory's extension lemma is now proved for ring_of_sets.
   195   - Infinite products of probability measures are now available.
   196   - Use extended reals instead of positive extended reals.
   197     INCOMPATIBILITY.
   198 
   199 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   200 must be loaded explicitly.  INCOMPATIBILITY.
   201 
   202 * Well-founded recursion combinator "wfrec" has been moved to
   203 Library/Wfrec.thy. INCOMPATIBILITY.
   204 
   205 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   206 The names of the following types and constants have changed:
   207   inat (type) ~> enat
   208   Fin         ~> enat
   209   Infty       ~> infinity (overloaded)
   210   iSuc        ~> eSuc
   211   the_Fin     ~> the_enat
   212 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   213 been renamed accordingly.
   214 
   215 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   216 accordance with standard mathematical terminology. INCOMPATIBILITY.
   217 
   218 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   219 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   220 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   221 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   222 changed to match. Definition theorems for overloaded constants now use
   223 the standard "foo_vec_def" naming scheme. A few other theorems have
   224 been renamed as follows (INCOMPATIBILITY):
   225 
   226   Cart_eq          ~> vec_eq_iff
   227   dist_nth_le_cart ~> dist_vec_nth_le
   228   tendsto_vector   ~> vec_tendstoI
   229   Cauchy_vector    ~> vec_CauchyI
   230 
   231 * Session Multivariate_Analysis: Several duplicate theorems have been
   232 removed, and other theorems have been renamed or replaced with more
   233 general versions. INCOMPATIBILITY.
   234 
   235   finite_choice ~> finite_set_choice
   236   eventually_conjI ~> eventually_conj
   237   eventually_and ~> eventually_conj_iff
   238   eventually_false ~> eventually_False
   239   setsum_norm ~> norm_setsum
   240   Lim_ident_at ~> LIM_ident
   241   Lim_const ~> tendsto_const
   242   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   243   Lim_neg ~> tendsto_minus
   244   Lim_add ~> tendsto_add
   245   Lim_sub ~> tendsto_diff
   246   Lim_mul ~> tendsto_scaleR
   247   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   248   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   249   Lim_linear ~> bounded_linear.tendsto
   250   Lim_component ~> tendsto_euclidean_component
   251   Lim_component_cart ~> tendsto_vec_nth
   252   Lim_inner ~> tendsto_inner [OF tendsto_const]
   253   dot_lsum ~> inner_setsum_left
   254   dot_rsum ~> inner_setsum_right
   255   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   256   continuous_neg ~> continuous_minus
   257   continuous_sub ~> continuous_diff
   258   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   259   continuous_mul ~> continuous_scaleR
   260   continuous_inv ~> continuous_inverse
   261   continuous_at_within_inv ~> continuous_at_within_inverse
   262   continuous_at_inv ~> continuous_at_inverse
   263   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   264   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   265   continuous_at_component ~> continuous_component [OF continuous_at_id]
   266   continuous_on_neg ~> continuous_on_minus
   267   continuous_on_sub ~> continuous_on_diff
   268   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   269   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   270   continuous_on_mul ~> continuous_on_scaleR
   271   continuous_on_mul_real ~> continuous_on_mult
   272   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   273   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   274   continuous_on_inverse ~> continuous_on_inv
   275   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   276   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   277   subset_interior ~> interior_mono
   278   subset_closure ~> closure_mono
   279   closure_univ ~> closure_UNIV
   280   real_arch_lt ~> reals_Archimedean2
   281   real_arch ~> reals_Archimedean3
   282   real_abs_norm ~> abs_norm_cancel
   283   real_abs_sub_norm ~> norm_triangle_ineq3
   284   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   285 
   286 * Complex_Main: The locale interpretations for the bounded_linear and
   287 bounded_bilinear locales have been removed, in order to reduce the
   288 number of duplicate lemmas. Users must use the original names for
   289 distributivity theorems, potential INCOMPATIBILITY.
   290 
   291   divide.add ~> add_divide_distrib
   292   divide.diff ~> diff_divide_distrib
   293   divide.setsum ~> setsum_divide_distrib
   294   mult.add_right ~> right_distrib
   295   mult.diff_right ~> right_diff_distrib
   296   mult_right.setsum ~> setsum_right_distrib
   297   mult_left.diff ~> left_diff_distrib
   298 
   299 * Complex_Main: Several redundant theorems have been removed or
   300 replaced by more general versions. INCOMPATIBILITY.
   301 
   302   real_0_le_divide_iff ~> zero_le_divide_iff
   303   realpow_two_disj ~> power2_eq_iff
   304   real_squared_diff_one_factored ~> square_diff_one_factored
   305   realpow_two_diff ~> square_diff_square_factored
   306   reals_complete2 ~> complete_real
   307   real_sum_squared_expand ~> power2_sum
   308   exp_ln_eq ~> ln_unique
   309   expi_add ~> exp_add
   310   expi_zero ~> exp_zero
   311   lemma_DERIV_subst ~> DERIV_cong
   312   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   313   LIMSEQ_const ~> tendsto_const
   314   LIMSEQ_norm ~> tendsto_norm
   315   LIMSEQ_add ~> tendsto_add
   316   LIMSEQ_minus ~> tendsto_minus
   317   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   318   LIMSEQ_diff ~> tendsto_diff
   319   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   320   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   321   LIMSEQ_mult ~> tendsto_mult
   322   LIMSEQ_inverse ~> tendsto_inverse
   323   LIMSEQ_divide ~> tendsto_divide
   324   LIMSEQ_pow ~> tendsto_power
   325   LIMSEQ_setsum ~> tendsto_setsum
   326   LIMSEQ_setprod ~> tendsto_setprod
   327   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   328   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   329   LIMSEQ_imp_rabs ~> tendsto_rabs
   330   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   331   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   332   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   333   LIMSEQ_Complex ~> tendsto_Complex
   334   LIM_ident ~> tendsto_ident_at
   335   LIM_const ~> tendsto_const
   336   LIM_add ~> tendsto_add
   337   LIM_add_zero ~> tendsto_add_zero
   338   LIM_minus ~> tendsto_minus
   339   LIM_diff ~> tendsto_diff
   340   LIM_norm ~> tendsto_norm
   341   LIM_norm_zero ~> tendsto_norm_zero
   342   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   343   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   344   LIM_rabs ~> tendsto_rabs
   345   LIM_rabs_zero ~> tendsto_rabs_zero
   346   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   347   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   348   LIM_compose ~> tendsto_compose
   349   LIM_mult ~> tendsto_mult
   350   LIM_scaleR ~> tendsto_scaleR
   351   LIM_of_real ~> tendsto_of_real
   352   LIM_power ~> tendsto_power
   353   LIM_inverse ~> tendsto_inverse
   354   LIM_sgn ~> tendsto_sgn
   355   isCont_LIM_compose ~> isCont_tendsto_compose
   356   bounded_linear.LIM ~> bounded_linear.tendsto
   357   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   358   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   359   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   360   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   361   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   362   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   363 
   364 
   365 *** Document preparation ***
   366 
   367 * Discontinued special treatment of hard tabulators, which are better
   368 avoided in the first place.  Implicit tab-width is 1.
   369 
   370 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   371 isar-ref manual.
   372 
   373 * Antiquotation @{value} evaluates the given term and presents its result.
   374 
   375 * Localized \isabellestyle switch can be used within blocks or groups
   376 like this:
   377 
   378   \isabellestyle{it}  %preferred default
   379   {\isabellestylett @{text "typewriter stuff"}}
   380 
   381 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   382 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   383 
   384 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   385 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   386 
   387 
   388 *** ML ***
   389 
   390 * The inner syntax of sort/type/term/prop supports inlined YXML
   391 representations within quoted string tokens.  By encoding logical
   392 entities via Term_XML (in ML or Scala) concrete syntax can be
   393 bypassed, which is particularly useful for producing bits of text
   394 under external program control.
   395 
   396 * Antiquotations for ML and document preparation are managed as theory
   397 data, which requires explicit setup.
   398 
   399 * Isabelle_Process.is_active allows tools to check if the official
   400 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   401 (better known as Proof General).
   402 
   403 * Structure Proof_Context follows standard naming scheme.  Old
   404 ProofContext is still available for some time as legacy alias.
   405 
   406 * Structure Timing provides various operations for timing; supersedes
   407 former start_timing/end_timing etc.
   408 
   409 * Path.print is the official way to show file-system paths to users
   410 (including quotes etc.).
   411 
   412 * Inner syntax: identifiers in parse trees of generic categories
   413 "logic", "aprop", "idt" etc. carry position information (disguised as
   414 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   415 translations that choke on unexpected type constraints.  Positions can
   416 be stripped in ML translations via Syntax.strip_positions /
   417 Syntax.strip_positions_ast, or via the syntax constant
   418 "_strip_positions" within parse trees.  As last resort, positions can
   419 be disabled via the configuration option Syntax.positions, which is
   420 called "syntax_positions" in Isar attribute syntax.
   421 
   422 * Discontinued special status of various ML structures that contribute
   423 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   424 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   425 refer directly to Ast.Constant, Lexicon.is_identifier,
   426 Syntax_Trans.mk_binder_tr etc.
   427 
   428 * Typed print translation: discontinued show_sorts argument, which is
   429 already available via context of "advanced" translation.
   430 
   431 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   432 goal states; body tactic needs to address all subgoals uniformly.
   433 
   434 * Slightly more special eq_list/eq_set, with shortcut involving
   435 pointer equality (assumes that eq relation is reflexive).
   436 
   437 * Classical tactics use proper Proof.context instead of historic types
   438 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   439 operate directly on Proof.context.  Raw type claset retains its use as
   440 snapshot of the classical context, which can be recovered via
   441 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   442 INCOMPATIBILITY, classical tactics and derived proof methods require
   443 proper Proof.context.
   444 
   445 * Scala layer provides JVM method invocation service for static
   446 methods of type (String)String, see Invoke_Scala.method in ML.
   447 For example:
   448 
   449   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   450 
   451 
   452 
   453 New in Isabelle2011 (January 2011)
   454 ----------------------------------
   455 
   456 *** General ***
   457 
   458 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   459 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   460 useful tooltips and hyperlinks produced from its static analysis.  The
   461 bundled component provides an executable Isabelle tool that can be run
   462 like this:
   463 
   464   Isabelle2011/bin/isabelle jedit
   465 
   466 * Significantly improved Isabelle/Isar implementation manual.
   467 
   468 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   469 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   470 while the default heap location within that directory lacks that extra
   471 suffix.  This isolates multiple Isabelle installations from each
   472 other, avoiding problems with old settings in new versions.
   473 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   474 
   475 * Source files are always encoded as UTF-8, instead of old-fashioned
   476 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   477 the following package declarations:
   478 
   479   \usepackage[utf8]{inputenc}
   480   \usepackage{textcomp}
   481 
   482 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   483 a Unicode character is treated as a single symbol, not a sequence of
   484 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   485 contain symbols without further backslash escapes, Unicode can now be
   486 used here as well.  Recall that Symbol.explode in ML provides a
   487 consistent view on symbols, while raw explode (or String.explode)
   488 merely give a byte-oriented representation.
   489 
   490 * Theory loader: source files are primarily located via the master
   491 directory of each theory node (where the .thy file itself resides).
   492 The global load path is still partially available as legacy feature.
   493 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   494 explicit paths, relatively to the theory.
   495 
   496 * Special treatment of ML file names has been discontinued.
   497 Historically, optional extensions .ML or .sml were added on demand --
   498 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   499 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   500 
   501 * Various options that affect pretty printing etc. are now properly
   502 handled within the context via configuration options, instead of
   503 unsynchronized references or print modes.  There are both ML Config.T
   504 entities and Isar declaration attributes to access these.
   505 
   506   ML (Config.T)                 Isar (attribute)
   507 
   508   eta_contract                  eta_contract
   509   show_brackets                 show_brackets
   510   show_sorts                    show_sorts
   511   show_types                    show_types
   512   show_question_marks           show_question_marks
   513   show_consts                   show_consts
   514   show_abbrevs                  show_abbrevs
   515 
   516   Syntax.ast_trace              syntax_ast_trace
   517   Syntax.ast_stat               syntax_ast_stat
   518   Syntax.ambiguity_level        syntax_ambiguity_level
   519 
   520   Goal_Display.goals_limit      goals_limit
   521   Goal_Display.show_main_goal   show_main_goal
   522 
   523   Method.rule_trace             rule_trace
   524 
   525   Thy_Output.display            thy_output_display
   526   Thy_Output.quotes             thy_output_quotes
   527   Thy_Output.indent             thy_output_indent
   528   Thy_Output.source             thy_output_source
   529   Thy_Output.break              thy_output_break
   530 
   531 Note that corresponding "..._default" references in ML may only be
   532 changed globally at the ROOT session setup, but *not* within a theory.
   533 The option "show_abbrevs" supersedes the former print mode
   534 "no_abbrevs" with inverted meaning.
   535 
   536 * More systematic naming of some configuration options.
   537 INCOMPATIBILITY.
   538 
   539   trace_simp  ~>  simp_trace
   540   debug_simp  ~>  simp_debug
   541 
   542 * Support for real valued configuration options, using simplistic
   543 floating-point notation that coincides with the inner syntax for
   544 float_token.
   545 
   546 * Support for real valued preferences (with approximative PGIP type):
   547 front-ends need to accept "pgint" values in float notation.
   548 INCOMPATIBILITY.
   549 
   550 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   551 DejaVu Sans.
   552 
   553 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   554 
   555 
   556 *** Pure ***
   557 
   558 * Command 'type_synonym' (with single argument) replaces somewhat
   559 outdated 'types', which is still available as legacy feature for some
   560 time.
   561 
   562 * Command 'nonterminal' (with 'and' separated list of arguments)
   563 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   564 
   565 * Command 'notepad' replaces former 'example_proof' for
   566 experimentation in Isar without any result.  INCOMPATIBILITY.
   567 
   568 * Locale interpretation commands 'interpret' and 'sublocale' accept
   569 lists of equations to map definitions in a locale to appropriate
   570 entities in the context of the interpretation.  The 'interpretation'
   571 command already provided this functionality.
   572 
   573 * Diagnostic command 'print_dependencies' prints the locale instances
   574 that would be activated if the specified expression was interpreted in
   575 the current context.  Variant "print_dependencies!" assumes a context
   576 without interpretations.
   577 
   578 * Diagnostic command 'print_interps' prints interpretations in proofs
   579 in addition to interpretations in theories.
   580 
   581 * Discontinued obsolete 'global' and 'local' commands to manipulate
   582 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   583 Sign.root_path and Sign.local_path may be applied directly where this
   584 feature is still required for historical reasons.
   585 
   586 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   587 'definition' instead.
   588 
   589 * The "prems" fact, which refers to the accidental collection of
   590 foundational premises in the context, is now explicitly marked as
   591 legacy feature and will be discontinued soon.  Consider using "assms"
   592 of the head statement or reference facts by explicit names.
   593 
   594 * Document antiquotations @{class} and @{type} print classes and type
   595 constructors.
   596 
   597 * Document antiquotation @{file} checks file/directory entries within
   598 the local file system.
   599 
   600 
   601 *** HOL ***
   602 
   603 * Coercive subtyping: functions can be declared as coercions and type
   604 inference will add them as necessary upon input of a term.  Theory
   605 Complex_Main declares real :: nat => real and real :: int => real as
   606 coercions. A coercion function f is declared like this:
   607 
   608   declare [[coercion f]]
   609 
   610 To lift coercions through type constructors (e.g. from nat => real to
   611 nat list => real list), map functions can be declared, e.g.
   612 
   613   declare [[coercion_map map]]
   614 
   615 Currently coercion inference is activated only in theories including
   616 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   617 the configuration option "coercion_enabled", e.g. it can be enabled in
   618 other theories like this:
   619 
   620   declare [[coercion_enabled]]
   621 
   622 * Command 'partial_function' provides basic support for recursive
   623 function definitions over complete partial orders.  Concrete instances
   624 are provided for i) the option type, ii) tail recursion on arbitrary
   625 types, and iii) the heap monad of Imperative_HOL.  See
   626 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   627 for examples.
   628 
   629 * Function package: f.psimps rules are no longer implicitly declared
   630 as [simp].  INCOMPATIBILITY.
   631 
   632 * Datatype package: theorems generated for executable equality (class
   633 "eq") carry proper names and are treated as default code equations.
   634 
   635 * Inductive package: now offers command 'inductive_simps' to
   636 automatically derive instantiated and simplified equations for
   637 inductive predicates, similar to 'inductive_cases'.
   638 
   639 * Command 'enriched_type' allows to register properties of the
   640 functorial structure of types.
   641 
   642 * Improved infrastructure for term evaluation using code generator
   643 techniques, in particular static evaluation conversions.
   644 
   645 * Code generator: Scala (2.8 or higher) has been added to the target
   646 languages.
   647 
   648 * Code generator: globbing constant expressions "*" and "Theory.*"
   649 have been replaced by the more idiomatic "_" and "Theory._".
   650 INCOMPATIBILITY.
   651 
   652 * Code generator: export_code without explicit file declaration prints
   653 to standard output.  INCOMPATIBILITY.
   654 
   655 * Code generator: do not print function definitions for case
   656 combinators any longer.
   657 
   658 * Code generator: simplification with rules determined with
   659 src/Tools/Code/code_simp.ML and method "code_simp".
   660 
   661 * Code generator for records: more idiomatic representation of record
   662 types.  Warning: records are not covered by ancient SML code
   663 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   664 rep_datatype declaration helps to succeed then:
   665 
   666   record 'a foo = ...
   667   ...
   668   rep_datatype foo_ext ...
   669 
   670 * Records: logical foundation type for records does not carry a
   671 '_type' suffix any longer (obsolete due to authentic syntax).
   672 INCOMPATIBILITY.
   673 
   674 * Quickcheck now by default uses exhaustive testing instead of random
   675 testing.  Random testing can be invoked by "quickcheck [random]",
   676 exhaustive testing by "quickcheck [exhaustive]".
   677 
   678 * Quickcheck instantiates polymorphic types with small finite
   679 datatypes by default. This enables a simple execution mechanism to
   680 handle quantifiers and function equality over the finite datatypes.
   681 
   682 * Quickcheck random generator has been renamed from "code" to
   683 "random".  INCOMPATIBILITY.
   684 
   685 * Quickcheck now has a configurable time limit which is set to 30
   686 seconds by default. This can be changed by adding [timeout = n] to the
   687 quickcheck command. The time limit for Auto Quickcheck is still set
   688 independently.
   689 
   690 * Quickcheck in locales considers interpretations of that locale for
   691 counter example search.
   692 
   693 * Sledgehammer:
   694   - Added "smt" and "remote_smt" provers based on the "smt" proof
   695     method. See the Sledgehammer manual for details ("isabelle doc
   696     sledgehammer").
   697   - Renamed commands:
   698     sledgehammer atp_info ~> sledgehammer running_provers
   699     sledgehammer atp_kill ~> sledgehammer kill_provers
   700     sledgehammer available_atps ~> sledgehammer available_provers
   701     INCOMPATIBILITY.
   702   - Renamed options:
   703     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   704     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   705     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   706     (and "ms" and "min" are no longer supported)
   707     INCOMPATIBILITY.
   708 
   709 * Nitpick:
   710   - Renamed options:
   711     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   712     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   713     INCOMPATIBILITY.
   714   - Added support for partial quotient types.
   715   - Added local versions of the "Nitpick.register_xxx" functions.
   716   - Added "whack" option.
   717   - Allow registration of quotient types as codatatypes.
   718   - Improved "merge_type_vars" option to merge more types.
   719   - Removed unsound "fast_descrs" option.
   720   - Added custom symmetry breaking for datatypes, making it possible to reach
   721     higher cardinalities.
   722   - Prevent the expansion of too large definitions.
   723 
   724 * Proof methods "metis" and "meson" now have configuration options
   725 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   726 to diagnose these tools. E.g.
   727 
   728     using [[metis_trace = true]]
   729 
   730 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   731 manually as command 'solve_direct'.
   732 
   733 * The default SMT solver Z3 must be enabled explicitly (due to
   734 licensing issues) by setting the environment variable
   735 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   736 commercial applications, the SMT solver CVC3 is provided as fall-back;
   737 changing the SMT solver is done via the configuration option
   738 "smt_solver".
   739 
   740 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   741 i.e. "remote_cvc3" and "remote_z3".
   742 
   743 * Added basic SMT support for datatypes, records, and typedefs using
   744 the oracle mode (no proofs).  Direct support of pairs has been dropped
   745 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   746 support for a similar behavior).  Minor INCOMPATIBILITY.
   747 
   748 * Changed SMT configuration options:
   749   - Renamed:
   750     z3_proofs ~> smt_oracle (with inverted meaning)
   751     z3_trace_assms ~> smt_trace_used_facts
   752     INCOMPATIBILITY.
   753   - Added:
   754     smt_verbose
   755     smt_random_seed
   756     smt_datatypes
   757     smt_infer_triggers
   758     smt_monomorph_limit
   759     cvc3_options
   760     remote_cvc3_options
   761     remote_z3_options
   762     yices_options
   763 
   764 * Boogie output files (.b2i files) need to be declared in the theory
   765 header.
   766 
   767 * Simplification procedure "list_to_set_comprehension" rewrites list
   768 comprehensions applied to List.set to set comprehensions.  Occasional
   769 INCOMPATIBILITY, may be deactivated like this:
   770 
   771   declare [[simproc del: list_to_set_comprehension]]
   772 
   773 * Removed old version of primrec package.  INCOMPATIBILITY.
   774 
   775 * Removed simplifier congruence rule of "prod_case", as has for long
   776 been the case with "split".  INCOMPATIBILITY.
   777 
   778 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   779 
   780 * Removed [split_format ... and ... and ...] version of
   781 [split_format].  Potential INCOMPATIBILITY.
   782 
   783 * Predicate "sorted" now defined inductively, with nice induction
   784 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   785 
   786 * Constant "contents" renamed to "the_elem", to free the generic name
   787 contents for other uses.  INCOMPATIBILITY.
   788 
   789 * Renamed class eq and constant eq (for code generation) to class
   790 equal and constant equal, plus renaming of related facts and various
   791 tuning.  INCOMPATIBILITY.
   792 
   793 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   794 
   795 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   796 INCOMPATIBILITY.
   797 
   798 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   799 avoid confusion with finite sets.  INCOMPATIBILITY.
   800 
   801 * Abandoned locales equiv, congruent and congruent2 for equivalence
   802 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   803 for congruent(2)).
   804 
   805 * Some previously unqualified names have been qualified:
   806 
   807   types
   808     bool ~> HOL.bool
   809     nat ~> Nat.nat
   810 
   811   constants
   812     Trueprop ~> HOL.Trueprop
   813     True ~> HOL.True
   814     False ~> HOL.False
   815     op & ~> HOL.conj
   816     op | ~> HOL.disj
   817     op --> ~> HOL.implies
   818     op = ~> HOL.eq
   819     Not ~> HOL.Not
   820     The ~> HOL.The
   821     All ~> HOL.All
   822     Ex ~> HOL.Ex
   823     Ex1 ~> HOL.Ex1
   824     Let ~> HOL.Let
   825     If ~> HOL.If
   826     Ball ~> Set.Ball
   827     Bex ~> Set.Bex
   828     Suc ~> Nat.Suc
   829     Pair ~> Product_Type.Pair
   830     fst ~> Product_Type.fst
   831     snd ~> Product_Type.snd
   832     curry ~> Product_Type.curry
   833     op : ~> Set.member
   834     Collect ~> Set.Collect
   835 
   836 INCOMPATIBILITY.
   837 
   838 * More canonical naming convention for some fundamental definitions:
   839 
   840     bot_bool_eq ~> bot_bool_def
   841     top_bool_eq ~> top_bool_def
   842     inf_bool_eq ~> inf_bool_def
   843     sup_bool_eq ~> sup_bool_def
   844     bot_fun_eq  ~> bot_fun_def
   845     top_fun_eq  ~> top_fun_def
   846     inf_fun_eq  ~> inf_fun_def
   847     sup_fun_eq  ~> sup_fun_def
   848 
   849 INCOMPATIBILITY.
   850 
   851 * More stylized fact names:
   852 
   853   expand_fun_eq ~> fun_eq_iff
   854   expand_set_eq ~> set_eq_iff
   855   set_ext       ~> set_eqI
   856   nat_number    ~> eval_nat_numeral
   857 
   858 INCOMPATIBILITY.
   859 
   860 * Refactoring of code-generation specific operations in theory List:
   861 
   862   constants
   863     null ~> List.null
   864 
   865   facts
   866     mem_iff ~> member_def
   867     null_empty ~> null_def
   868 
   869 INCOMPATIBILITY.  Note that these were not supposed to be used
   870 regularly unless for striking reasons; their main purpose was code
   871 generation.
   872 
   873 Various operations from the Haskell prelude are used for generating
   874 Haskell code.
   875 
   876 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   877 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   878 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   879 
   880 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   881 "*" and "+" respectively.  INCOMPATIBILITY.
   882 
   883 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   884 "Sum_Type.Plus" instead.
   885 
   886 * Constant "split" has been merged with constant "prod_case"; names of
   887 ML functions, facts etc. involving split have been retained so far,
   888 though.  INCOMPATIBILITY.
   889 
   890 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   891 instead.  INCOMPATIBILITY.
   892 
   893 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   894 INCOMPATIBILITY.
   895 
   896 * Former theory Library/Enum is now part of the HOL-Main image.
   897 INCOMPATIBILITY: all constants of the Enum theory now have to be
   898 referred to by its qualified name.
   899 
   900   enum    ~>  Enum.enum
   901   nlists  ~>  Enum.nlists
   902   product ~>  Enum.product
   903 
   904 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   905 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   906 INCOMPATIBILITY.
   907 
   908 * Theory Library/SetsAndFunctions has been split into
   909 Library/Function_Algebras and Library/Set_Algebras; canonical names
   910 for instance definitions for functions; various improvements.
   911 INCOMPATIBILITY.
   912 
   913 * Theory Library/Multiset provides stable quicksort implementation of
   914 sort_key.
   915 
   916 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   917 INCOMPATIBILITY.
   918 
   919 * Session Multivariate_Analysis: introduced a type class for euclidean
   920 space.  Most theorems are now stated in terms of euclidean spaces
   921 instead of finite cartesian products.
   922 
   923   types
   924     real ^ 'n ~>  'a::real_vector
   925               ~>  'a::euclidean_space
   926               ~>  'a::ordered_euclidean_space
   927         (depends on your needs)
   928 
   929   constants
   930      _ $ _        ~> _ $$ _
   931      \<chi> x. _  ~> \<chi>\<chi> x. _
   932      CARD('n)     ~> DIM('a)
   933 
   934 Also note that the indices are now natural numbers and not from some
   935 finite type. Finite cartesian products of euclidean spaces, products
   936 of euclidean spaces the real and complex numbers are instantiated to
   937 be euclidean_spaces.  INCOMPATIBILITY.
   938 
   939 * Session Probability: introduced pextreal as positive extended real
   940 numbers.  Use pextreal as value for measures.  Introduce the
   941 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   942 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   943 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   944 
   945 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   946 INCOMPATIBILITY.
   947 
   948 * Session SPARK (with image HOL-SPARK) provides commands to load and
   949 prove verification conditions generated by the SPARK Ada program
   950 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   951 
   952 
   953 *** HOL-Algebra ***
   954 
   955 * Theorems for additive ring operations (locale abelian_monoid and
   956 descendants) are generated by interpretation from their multiplicative
   957 counterparts.  Names (in particular theorem names) have the mandatory
   958 qualifier 'add'.  Previous theorem names are redeclared for
   959 compatibility.
   960 
   961 * Structure "int_ring" is now an abbreviation (previously a
   962 definition).  This fits more natural with advanced interpretations.
   963 
   964 
   965 *** HOLCF ***
   966 
   967 * The domain package now runs in definitional mode by default: The
   968 former command 'new_domain' is now called 'domain'.  To use the domain
   969 package in its original axiomatic mode, use 'domain (unsafe)'.
   970 INCOMPATIBILITY.
   971 
   972 * The new class "domain" is now the default sort.  Class "predomain"
   973 is an unpointed version of "domain". Theories can be updated by
   974 replacing sort annotations as shown below.  INCOMPATIBILITY.
   975 
   976   'a::type ~> 'a::countable
   977   'a::cpo  ~> 'a::predomain
   978   'a::pcpo ~> 'a::domain
   979 
   980 * The old type class "rep" has been superseded by class "domain".
   981 Accordingly, users of the definitional package must remove any
   982 "default_sort rep" declarations.  INCOMPATIBILITY.
   983 
   984 * The domain package (definitional mode) now supports unpointed
   985 predomain argument types, as long as they are marked 'lazy'. (Strict
   986 arguments must be in class "domain".) For example, the following
   987 domain definition now works:
   988 
   989   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   990 
   991 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   992 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   993 'a option, and 'a list.  Additionally, it configures fixrec and the
   994 domain package to work with these types.  For example:
   995 
   996   fixrec isInl :: "('a + 'b) u -> tr"
   997     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   998 
   999   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1000 
  1001 * The "(permissive)" option of fixrec has been replaced with a
  1002 per-equation "(unchecked)" option. See
  1003 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1004 
  1005 * The "bifinite" class no longer fixes a constant "approx"; the class
  1006 now just asserts that such a function exists.  INCOMPATIBILITY.
  1007 
  1008 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1009 defines an embedding of type 'a defl into udom by default; instances
  1010 of "bifinite" and "domain" classes are available in
  1011 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1012 
  1013 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1014 
  1015 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1016 
  1017 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1018 
  1019 * The function "cprod_map" has been renamed to "prod_map".
  1020 INCOMPATIBILITY.
  1021 
  1022 * The monadic bind operator on each powerdomain has new binder syntax
  1023 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1024 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1025 
  1026 * The infix syntax for binary union on each powerdomain has changed
  1027 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1028 syntax.  INCOMPATIBILITY.
  1029 
  1030 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1031 still supported as an input translation.
  1032 
  1033 * Renamed some theorems (the original names are also still available).
  1034 
  1035   expand_fun_below   ~> fun_below_iff
  1036   below_fun_ext      ~> fun_belowI
  1037   expand_cfun_eq     ~> cfun_eq_iff
  1038   ext_cfun           ~> cfun_eqI
  1039   expand_cfun_below  ~> cfun_below_iff
  1040   below_cfun_ext     ~> cfun_belowI
  1041   cont2cont_Rep_CFun ~> cont2cont_APP
  1042 
  1043 * The Abs and Rep functions for various types have changed names.
  1044 Related theorem names have also changed to match. INCOMPATIBILITY.
  1045 
  1046   Rep_CFun  ~> Rep_cfun
  1047   Abs_CFun  ~> Abs_cfun
  1048   Rep_Sprod ~> Rep_sprod
  1049   Abs_Sprod ~> Abs_sprod
  1050   Rep_Ssum  ~> Rep_ssum
  1051   Abs_Ssum  ~> Abs_ssum
  1052 
  1053 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1054 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1055 
  1056 * Various changes to bisimulation/coinduction with domain package:
  1057 
  1058   - Definitions of "bisim" constants no longer mention definedness.
  1059   - With mutual recursion, "bisim" predicate is now curried.
  1060   - With mutual recursion, each type gets a separate coind theorem.
  1061   - Variable names in bisim_def and coinduct rules have changed.
  1062 
  1063 INCOMPATIBILITY.
  1064 
  1065 * Case combinators generated by the domain package for type "foo" are
  1066 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1067 
  1068 * Several theorems have been renamed to more accurately reflect the
  1069 names of constants and types involved.  INCOMPATIBILITY.
  1070 
  1071   thelub_const    ~> lub_const
  1072   lub_const       ~> is_lub_const
  1073   thelubI         ~> lub_eqI
  1074   is_lub_lub      ~> is_lubD2
  1075   lubI            ~> is_lub_lub
  1076   unique_lub      ~> is_lub_unique
  1077   is_ub_lub       ~> is_lub_rangeD1
  1078   lub_bin_chain   ~> is_lub_bin_chain
  1079   lub_fun         ~> is_lub_fun
  1080   thelub_fun      ~> lub_fun
  1081   thelub_cfun     ~> lub_cfun
  1082   thelub_Pair     ~> lub_Pair
  1083   lub_cprod       ~> is_lub_prod
  1084   thelub_cprod    ~> lub_prod
  1085   minimal_cprod   ~> minimal_prod
  1086   inst_cprod_pcpo ~> inst_prod_pcpo
  1087   UU_I            ~> bottomI
  1088   compact_UU      ~> compact_bottom
  1089   deflation_UU    ~> deflation_bottom
  1090   finite_deflation_UU ~> finite_deflation_bottom
  1091 
  1092 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1093 
  1094   sq_ord_less_eq_trans ~> below_eq_trans
  1095   sq_ord_eq_less_trans ~> eq_below_trans
  1096   refl_less            ~> below_refl
  1097   trans_less           ~> below_trans
  1098   antisym_less         ~> below_antisym
  1099   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1100   box_less             ~> box_below
  1101   rev_trans_less       ~> rev_below_trans
  1102   not_less2not_eq      ~> not_below2not_eq
  1103   less_UU_iff          ~> below_UU_iff
  1104   flat_less_iff        ~> flat_below_iff
  1105   adm_less             ~> adm_below
  1106   adm_not_less         ~> adm_not_below
  1107   adm_compact_not_less ~> adm_compact_not_below
  1108   less_fun_def         ~> below_fun_def
  1109   expand_fun_less      ~> fun_below_iff
  1110   less_fun_ext         ~> fun_belowI
  1111   less_discr_def       ~> below_discr_def
  1112   discr_less_eq        ~> discr_below_eq
  1113   less_unit_def        ~> below_unit_def
  1114   less_cprod_def       ~> below_prod_def
  1115   prod_lessI           ~> prod_belowI
  1116   Pair_less_iff        ~> Pair_below_iff
  1117   fst_less_iff         ~> fst_below_iff
  1118   snd_less_iff         ~> snd_below_iff
  1119   expand_cfun_less     ~> cfun_below_iff
  1120   less_cfun_ext        ~> cfun_belowI
  1121   injection_less       ~> injection_below
  1122   less_up_def          ~> below_up_def
  1123   not_Iup_less         ~> not_Iup_below
  1124   Iup_less             ~> Iup_below
  1125   up_less              ~> up_below
  1126   Def_inject_less_eq   ~> Def_below_Def
  1127   Def_less_is_eq       ~> Def_below_iff
  1128   spair_less_iff       ~> spair_below_iff
  1129   less_sprod           ~> below_sprod
  1130   spair_less           ~> spair_below
  1131   sfst_less_iff        ~> sfst_below_iff
  1132   ssnd_less_iff        ~> ssnd_below_iff
  1133   fix_least_less       ~> fix_least_below
  1134   dist_less_one        ~> dist_below_one
  1135   less_ONE             ~> below_ONE
  1136   ONE_less_iff         ~> ONE_below_iff
  1137   less_sinlD           ~> below_sinlD
  1138   less_sinrD           ~> below_sinrD
  1139 
  1140 
  1141 *** FOL and ZF ***
  1142 
  1143 * All constant names are now qualified internally and use proper
  1144 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1145 
  1146 
  1147 *** ML ***
  1148 
  1149 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1150 Fail if the argument is false.  Due to inlining the source position of
  1151 failed assertions is included in the error output.
  1152 
  1153 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1154 text is in practice always evaluated with a stable theory checkpoint.
  1155 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1156 
  1157 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1158 the current context, not any accidental theory loader state as before.
  1159 Potential INCOMPATIBILITY, subtle change in semantics.
  1160 
  1161 * Syntax.pretty_priority (default 0) configures the required priority
  1162 of pretty-printed output and thus affects insertion of parentheses.
  1163 
  1164 * Syntax.default_root (default "any") configures the inner syntax
  1165 category (nonterminal symbol) for parsing of terms.
  1166 
  1167 * Former exception Library.UnequalLengths now coincides with
  1168 ListPair.UnequalLengths.
  1169 
  1170 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1171 main functionality is provided by structure Simplifier.
  1172 
  1173 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1174 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1175 almost all situations.
  1176 
  1177 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1178 See implementation manual for further details on exceptions in
  1179 Isabelle/ML.
  1180 
  1181 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1182 meaning.
  1183 
  1184 * Renamed structure PureThy to Pure_Thy and moved most of its
  1185 operations to structure Global_Theory, to emphasize that this is
  1186 rarely-used global-only stuff.
  1187 
  1188 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1189 instead (or tracing for high-volume output).
  1190 
  1191 * Configuration option show_question_marks only affects regular pretty
  1192 printing of types and terms, not raw Term.string_of_vname.
  1193 
  1194 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1195 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1196 @{thms} for most purposes.
  1197 
  1198 * ML structure Unsynchronized is never opened, not even in Isar
  1199 interaction mode as before.  Old Unsynchronized.set etc. have been
  1200 discontinued -- use plain := instead.  This should be *rare* anyway,
  1201 since modern tools always work via official context data, notably
  1202 configuration options.
  1203 
  1204 * Parallel and asynchronous execution requires special care concerning
  1205 interrupts.  Structure Exn provides some convenience functions that
  1206 avoid working directly with raw Interrupt.  User code must not absorb
  1207 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1208 followed by re-raising of the original exception.  Another common
  1209 source of mistakes are "handle _" patterns, which make the meaning of
  1210 the program subject to physical effects of the environment.
  1211 
  1212 
  1213 
  1214 New in Isabelle2009-2 (June 2010)
  1215 ---------------------------------
  1216 
  1217 *** General ***
  1218 
  1219 * Authentic syntax for *all* logical entities (type classes, type
  1220 constructors, term constants): provides simple and robust
  1221 correspondence between formal entities and concrete syntax.  Within
  1222 the parse tree / AST representations, "constants" are decorated by
  1223 their category (class, type, const) and spelled out explicitly with
  1224 their full internal name.
  1225 
  1226 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1227 and translations (translation rules and translation functions in ML).
  1228 Some hints on upgrading:
  1229 
  1230   - Many existing uses of 'syntax' and 'translations' can be replaced
  1231     by more modern 'type_notation', 'notation' and 'abbreviation',
  1232     which are independent of this issue.
  1233 
  1234   - 'translations' require markup within the AST; the term syntax
  1235     provides the following special forms:
  1236 
  1237       CONST c   -- produces syntax version of constant c from context
  1238       XCONST c  -- literally c, checked as constant from context
  1239       c         -- literally c, if declared by 'syntax'
  1240 
  1241     Plain identifiers are treated as AST variables -- occasionally the
  1242     system indicates accidental variables via the error "rhs contains
  1243     extra variables".
  1244 
  1245     Type classes and type constructors are marked according to their
  1246     concrete syntax.  Some old translations rules need to be written
  1247     for the "type" category, using type constructor application
  1248     instead of pseudo-term application of the default category
  1249     "logic".
  1250 
  1251   - 'parse_translation' etc. in ML may use the following
  1252     antiquotations:
  1253 
  1254       @{class_syntax c}   -- type class c within parse tree / AST
  1255       @{term_syntax c}    -- type constructor c within parse tree / AST
  1256       @{const_syntax c}   -- ML version of "CONST c" above
  1257       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1258 
  1259   - Literal types within 'typed_print_translations', i.e. those *not*
  1260     represented as pseudo-terms are represented verbatim.  Use @{class
  1261     c} or @{type_name c} here instead of the above syntax
  1262     antiquotations.
  1263 
  1264 Note that old non-authentic syntax was based on unqualified base
  1265 names, so all of the above "constant" names would coincide.  Recall
  1266 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1267 diagnose syntax problems.
  1268 
  1269 * Type constructors admit general mixfix syntax, not just infix.
  1270 
  1271 * Concrete syntax may be attached to local entities without a proof
  1272 body, too.  This works via regular mixfix annotations for 'fix',
  1273 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1274 similar to the 'notation' command in theory specifications.
  1275 
  1276 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1277 need to specify constant name and syntax separately.  Internal ML
  1278 datatype constructors have been renamed from InfixName to Infix etc.
  1279 Minor INCOMPATIBILITY.
  1280 
  1281 * Schematic theorem statements need to be explicitly markup as such,
  1282 via commands 'schematic_lemma', 'schematic_theorem',
  1283 'schematic_corollary'.  Thus the relevance of the proof is made
  1284 syntactically clear, which impacts performance in a parallel or
  1285 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1286 
  1287 * Use of cumulative prems via "!" in some proof methods has been
  1288 discontinued (old legacy feature).
  1289 
  1290 * References 'trace_simp' and 'debug_simp' have been replaced by
  1291 configuration options stored in the context. Enabling tracing (the
  1292 case of debugging is similar) in proofs works via
  1293 
  1294   using [[trace_simp = true]]
  1295 
  1296 Tracing is then active for all invocations of the simplifier in
  1297 subsequent goal refinement steps. Tracing may also still be enabled or
  1298 disabled via the ProofGeneral settings menu.
  1299 
  1300 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1301 'hide_fact' replace the former 'hide' KIND command.  Minor
  1302 INCOMPATIBILITY.
  1303 
  1304 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1305 more efficient than combinations with -q1 or -q2.
  1306 
  1307 
  1308 *** Pure ***
  1309 
  1310 * Proofterms record type-class reasoning explicitly, using the
  1311 "unconstrain" operation internally.  This eliminates all sort
  1312 constraints from a theorem and proof, introducing explicit
  1313 OFCLASS-premises.  On the proof term level, this operation is
  1314 automatically applied at theorem boundaries, such that closed proofs
  1315 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1316 inspect proof terms.
  1317 
  1318 * Local theory specifications may depend on extra type variables that
  1319 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1320 are added internally.  For example:
  1321 
  1322   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1323 
  1324 * Predicates of locales introduced by classes carry a mandatory
  1325 "class" prefix.  INCOMPATIBILITY.
  1326 
  1327 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1328 
  1329 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1330 'class' instead.
  1331 
  1332 * Command 'code_reflect' allows to incorporate generated ML code into
  1333 runtime environment; replaces immature code_datatype antiquotation.
  1334 INCOMPATIBILITY.
  1335 
  1336 * Code generator: simple concept for abstract datatypes obeying
  1337 invariants.
  1338 
  1339 * Code generator: details of internal data cache have no impact on the
  1340 user space functionality any longer.
  1341 
  1342 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1343 subgoals.  This is more appropriate for interpretations with 'where'.
  1344 INCOMPATIBILITY.
  1345 
  1346 * Command 'example_proof' opens an empty proof body.  This allows to
  1347 experiment with Isar, without producing any persistent result.
  1348 
  1349 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1350 within a local theory context, with explicit checking of the
  1351 constructors involved (in contrast to the raw 'syntax' versions).
  1352 
  1353 * Commands 'types' and 'typedecl' now work within a local theory
  1354 context -- without introducing dependencies on parameters or
  1355 assumptions, which is not possible in Isabelle/Pure.
  1356 
  1357 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1358 within a local theory context.  Minor INCOMPATIBILITY.
  1359 
  1360 
  1361 *** HOL ***
  1362 
  1363 * Command 'typedef' now works within a local theory context -- without
  1364 introducing dependencies on parameters or assumptions, which is not
  1365 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1366 contain multiple interpretations of local typedefs (with different
  1367 non-emptiness proofs), even in a global theory context.
  1368 
  1369 * New package for quotient types.  Commands 'quotient_type' and
  1370 'quotient_definition' may be used for defining types and constants by
  1371 quotient constructions.  An example is the type of integers created by
  1372 quotienting pairs of natural numbers:
  1373 
  1374   fun
  1375     intrel :: "(nat * nat) => (nat * nat) => bool"
  1376   where
  1377     "intrel (x, y) (u, v) = (x + v = u + y)"
  1378 
  1379   quotient_type int = "nat * nat" / intrel
  1380     by (auto simp add: equivp_def expand_fun_eq)
  1381 
  1382   quotient_definition
  1383     "0::int" is "(0::nat, 0::nat)"
  1384 
  1385 The method "lifting" can be used to lift of theorems from the
  1386 underlying "raw" type to the quotient type.  The example
  1387 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1388 construction and provides a reasoning infrastructure for finite sets.
  1389 
  1390 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1391 clash with new theory Quotient in Main HOL.
  1392 
  1393 * Moved the SMT binding into the main HOL session, eliminating
  1394 separate HOL-SMT session.
  1395 
  1396 * List membership infix mem operation is only an input abbreviation.
  1397 INCOMPATIBILITY.
  1398 
  1399 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1400 for future developements; former Library/Word.thy is still present in
  1401 the AFP entry RSAPPS.
  1402 
  1403 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1404 longer shadowed.  INCOMPATIBILITY.
  1405 
  1406 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1407 INCOMPATIBILITY.
  1408 
  1409 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1410 INCOMPATIBILITY.
  1411 
  1412 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1413 instead.  INCOMPATIBILITY.
  1414 
  1415 * Dropped several real-specific versions of lemmas about floor and
  1416 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1417 instead.  INCOMPATIBILITY.
  1418 
  1419   floor_number_of_eq         ~> floor_number_of
  1420   le_floor_eq_number_of      ~> number_of_le_floor
  1421   le_floor_eq_zero           ~> zero_le_floor
  1422   le_floor_eq_one            ~> one_le_floor
  1423   floor_less_eq_number_of    ~> floor_less_number_of
  1424   floor_less_eq_zero         ~> floor_less_zero
  1425   floor_less_eq_one          ~> floor_less_one
  1426   less_floor_eq_number_of    ~> number_of_less_floor
  1427   less_floor_eq_zero         ~> zero_less_floor
  1428   less_floor_eq_one          ~> one_less_floor
  1429   floor_le_eq_number_of      ~> floor_le_number_of
  1430   floor_le_eq_zero           ~> floor_le_zero
  1431   floor_le_eq_one            ~> floor_le_one
  1432   floor_subtract_number_of   ~> floor_diff_number_of
  1433   floor_subtract_one         ~> floor_diff_one
  1434   ceiling_number_of_eq       ~> ceiling_number_of
  1435   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1436   ceiling_le_zero_eq         ~> ceiling_le_zero
  1437   ceiling_le_eq_one          ~> ceiling_le_one
  1438   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1439   less_ceiling_eq_zero       ~> zero_less_ceiling
  1440   less_ceiling_eq_one        ~> one_less_ceiling
  1441   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1442   ceiling_less_eq_zero       ~> ceiling_less_zero
  1443   ceiling_less_eq_one        ~> ceiling_less_one
  1444   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1445   le_ceiling_eq_zero         ~> zero_le_ceiling
  1446   le_ceiling_eq_one          ~> one_le_ceiling
  1447   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1448   ceiling_subtract_one       ~> ceiling_diff_one
  1449 
  1450 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1451 application of the various fold combinators on finite sets.
  1452 
  1453 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1454 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1455 implementation.  INCOMPATIBILTY.
  1456 
  1457 * Theory Library/Coinductive_List has been removed -- superseded by
  1458 AFP/thys/Coinductive.
  1459 
  1460 * Theory PReal, including the type "preal" and related operations, has
  1461 been removed.  INCOMPATIBILITY.
  1462 
  1463 * Real: new development using Cauchy Sequences.
  1464 
  1465 * Split off theory "Big_Operators" containing setsum, setprod,
  1466 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1467 
  1468 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1469 "Int" etc.  INCOMPATIBILITY.
  1470 
  1471 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1472 
  1473 * New set of rules "ac_simps" provides combined assoc / commute
  1474 rewrites for all interpretations of the appropriate generic locales.
  1475 
  1476 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1477 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1478 appropriate and more consistent names suitable for name prefixes
  1479 within the HOL theories.  INCOMPATIBILITY.
  1480 
  1481 * Some generic constants have been put to appropriate theories:
  1482   - less_eq, less: Orderings
  1483   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1484   - inverse, divide: Rings
  1485 INCOMPATIBILITY.
  1486 
  1487 * More consistent naming of type classes involving orderings (and
  1488 lattices):
  1489 
  1490     lower_semilattice                   ~> semilattice_inf
  1491     upper_semilattice                   ~> semilattice_sup
  1492 
  1493     dense_linear_order                  ~> dense_linorder
  1494 
  1495     pordered_ab_group_add               ~> ordered_ab_group_add
  1496     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1497     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1498     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1499     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1500     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1501     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1502     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1503     pordered_comm_ring                  ~> ordered_comm_ring
  1504     pordered_comm_semiring              ~> ordered_comm_semiring
  1505     pordered_ring                       ~> ordered_ring
  1506     pordered_ring_abs                   ~> ordered_ring_abs
  1507     pordered_semiring                   ~> ordered_semiring
  1508 
  1509     ordered_ab_group_add                ~> linordered_ab_group_add
  1510     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1511     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1512     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1513     ordered_field                       ~> linordered_field
  1514     ordered_field_no_lb                 ~> linordered_field_no_lb
  1515     ordered_field_no_ub                 ~> linordered_field_no_ub
  1516     ordered_field_dense_linear_order    ~> dense_linordered_field
  1517     ordered_idom                        ~> linordered_idom
  1518     ordered_ring                        ~> linordered_ring
  1519     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1520     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1521     ordered_ring_strict                 ~> linordered_ring_strict
  1522     ordered_semidom                     ~> linordered_semidom
  1523     ordered_semiring                    ~> linordered_semiring
  1524     ordered_semiring_1                  ~> linordered_semiring_1
  1525     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1526     ordered_semiring_strict             ~> linordered_semiring_strict
  1527 
  1528   The following slightly odd type classes have been moved to a
  1529   separate theory Library/Lattice_Algebras:
  1530 
  1531     lordered_ab_group_add               ~> lattice_ab_group_add
  1532     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1533     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1534     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1535     lordered_ring                       ~> lattice_ring
  1536 
  1537 INCOMPATIBILITY.
  1538 
  1539 * Refined field classes:
  1540   - classes division_ring_inverse_zero, field_inverse_zero,
  1541     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1542     subsumes former division_by_zero class;
  1543   - numerous lemmas have been ported from field to division_ring.
  1544 INCOMPATIBILITY.
  1545 
  1546 * Refined algebra theorem collections:
  1547   - dropped theorem group group_simps, use algebra_simps instead;
  1548   - dropped theorem group ring_simps, use field_simps instead;
  1549   - proper theorem collection field_simps subsumes former theorem
  1550     groups field_eq_simps and field_simps;
  1551   - dropped lemma eq_minus_self_iff which is a duplicate for
  1552     equal_neg_zero.
  1553 INCOMPATIBILITY.
  1554 
  1555 * Theory Finite_Set and List: some lemmas have been generalized from
  1556 sets to lattices:
  1557 
  1558   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1559   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1560   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1561   union_Union_fold_union        ~> sup_Sup_fold_sup
  1562   Inter_fold_inter              ~> Inf_fold_inf
  1563   Union_fold_union              ~> Sup_fold_sup
  1564   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1565   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1566   INTER_fold_inter              ~> INFI_fold_inf
  1567   UNION_fold_union              ~> SUPR_fold_sup
  1568 
  1569 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1570 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1571 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1572 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1573 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1574 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1575 
  1576 * Reorganized theory Multiset: swapped notation of pointwise and
  1577 multiset order:
  1578 
  1579   - pointwise ordering is instance of class order with standard syntax
  1580     <= and <;
  1581   - multiset ordering has syntax <=# and <#; partial order properties
  1582     are provided by means of interpretation with prefix
  1583     multiset_order;
  1584   - less duplication, less historical organization of sections,
  1585     conversion from associations lists to multisets, rudimentary code
  1586     generation;
  1587   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1588     if needed.
  1589 
  1590 Renamed:
  1591 
  1592   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1593   multi_count_ext  ~>  multiset_ext
  1594   diff_union_inverse2  ~>  diff_union_cancelR
  1595 
  1596 INCOMPATIBILITY.
  1597 
  1598 * Theory Permutation: replaced local "remove" by List.remove1.
  1599 
  1600 * Code generation: ML and OCaml code is decorated with signatures.
  1601 
  1602 * Theory List: added transpose.
  1603 
  1604 * Library/Nat_Bijection.thy is a collection of bijective functions
  1605 between nat and other types, which supersedes the older libraries
  1606 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1607 
  1608   Constants:
  1609   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1610   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1611   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1612   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1613   Countable.pair_encode           ~> prod_encode
  1614   NatIso.prod2nat                 ~> prod_encode
  1615   NatIso.nat2prod                 ~> prod_decode
  1616   NatIso.sum2nat                  ~> sum_encode
  1617   NatIso.nat2sum                  ~> sum_decode
  1618   NatIso.list2nat                 ~> list_encode
  1619   NatIso.nat2list                 ~> list_decode
  1620   NatIso.set2nat                  ~> set_encode
  1621   NatIso.nat2set                  ~> set_decode
  1622 
  1623   Lemmas:
  1624   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1625   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1626   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1627   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1628   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1629   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1630   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1631   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1632   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1633   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1634   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1635   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1636   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1637 
  1638 * Sledgehammer:
  1639   - Renamed ATP commands:
  1640     atp_info     ~> sledgehammer running_atps
  1641     atp_kill     ~> sledgehammer kill_atps
  1642     atp_messages ~> sledgehammer messages
  1643     atp_minimize ~> sledgehammer minimize
  1644     print_atps   ~> sledgehammer available_atps
  1645     INCOMPATIBILITY.
  1646   - Added user's manual ("isabelle doc sledgehammer").
  1647   - Added option syntax and "sledgehammer_params" to customize
  1648     Sledgehammer's behavior.  See the manual for details.
  1649   - Modified the Isar proof reconstruction code so that it produces
  1650     direct proofs rather than proofs by contradiction.  (This feature
  1651     is still experimental.)
  1652   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1653     full-typed mode.
  1654   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1655 
  1656 * Nitpick:
  1657   - Added and implemented "binary_ints" and "bits" options.
  1658   - Added "std" option and implemented support for nonstandard models.
  1659   - Added and implemented "finitize" option to improve the precision
  1660     of infinite datatypes based on a monotonicity analysis.
  1661   - Added support for quotient types.
  1662   - Added support for "specification" and "ax_specification"
  1663     constructs.
  1664   - Added support for local definitions (for "function" and
  1665     "termination" proofs).
  1666   - Added support for term postprocessors.
  1667   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1668   - Improved efficiency of "destroy_constrs" optimization.
  1669   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1670     record getters.
  1671   - Fixed soundness bug related to higher-order constructors.
  1672   - Fixed soundness bug when "full_descrs" is enabled.
  1673   - Improved precision of set constructs.
  1674   - Added "atoms" option.
  1675   - Added cache to speed up repeated Kodkod invocations on the same
  1676     problems.
  1677   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1678     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1679     "SAT4J_Light".  INCOMPATIBILITY.
  1680   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1681     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1682   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1683 
  1684 * Method "induct" now takes instantiations of the form t, where t is not
  1685   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1686   If this is not intended, t has to be enclosed in parentheses.
  1687   By default, the equalities generated by definitional instantiations
  1688   are pre-simplified, which may cause parameters of inductive cases
  1689   to disappear, or may even delete some of the inductive cases.
  1690   Use "induct (no_simp)" instead of "induct" to restore the old
  1691   behaviour. The (no_simp) option is also understood by the "cases"
  1692   and "nominal_induct" methods, which now perform pre-simplification, too.
  1693   INCOMPATIBILITY.
  1694 
  1695 
  1696 *** HOLCF ***
  1697 
  1698 * Variable names in lemmas generated by the domain package have
  1699 changed; the naming scheme is now consistent with the HOL datatype
  1700 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1701 
  1702 * The domain package no longer defines the function "foo_copy" for
  1703 recursive domain "foo".  The reach lemma is now stated directly in
  1704 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1705 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1706 
  1707 * Most definedness lemmas generated by the domain package (previously
  1708 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1709 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1710 Proofs that used definedness lemmas as intro rules may break,
  1711 potential INCOMPATIBILITY.
  1712 
  1713 * Induction and casedist rules generated by the domain package now
  1714 declare proper case_names (one called "bottom", and one named for each
  1715 constructor).  INCOMPATIBILITY.
  1716 
  1717 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1718 rules are generated for each domain, INCOMPATIBILITY.
  1719 
  1720   foo_bar.reach       ~> foo.reach  bar.reach
  1721   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1722 
  1723 * Some lemmas generated by the domain package have been renamed for
  1724 consistency with the datatype package, INCOMPATIBILITY.
  1725 
  1726   foo.ind        ~> foo.induct
  1727   foo.finite_ind ~> foo.finite_induct
  1728   foo.coind      ~> foo.coinduct
  1729   foo.casedist   ~> foo.exhaust
  1730   foo.exhaust    ~> foo.nchotomy
  1731 
  1732 * For consistency with other definition packages, the fixrec package
  1733 now generates qualified theorem names, INCOMPATIBILITY.
  1734 
  1735   foo_simps  ~> foo.simps
  1736   foo_unfold ~> foo.unfold
  1737   foo_induct ~> foo.induct
  1738 
  1739 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1740 method and internal fixrec proofs now use the default simpset instead.
  1741 INCOMPATIBILITY.
  1742 
  1743 * The "contlub" predicate has been removed.  Proof scripts should use
  1744 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1745 
  1746 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1747 
  1748 * The constants cpair, cfst, and csnd have been removed in favor of
  1749 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1750 
  1751 
  1752 *** ML ***
  1753 
  1754 * Antiquotations for basic formal entities:
  1755 
  1756     @{class NAME}         -- type class
  1757     @{class_syntax NAME}  -- syntax representation of the above
  1758 
  1759     @{type_name NAME}     -- logical type
  1760     @{type_abbrev NAME}   -- type abbreviation
  1761     @{nonterminal NAME}   -- type of concrete syntactic category
  1762     @{type_syntax NAME}   -- syntax representation of any of the above
  1763 
  1764     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1765     @{const_abbrev NAME}  -- abbreviated constant
  1766     @{const_syntax NAME}  -- syntax representation of any of the above
  1767 
  1768 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1769 syntax constant (cf. 'syntax' command).
  1770 
  1771 * Antiquotation @{make_string} inlines a function to print arbitrary
  1772 values similar to the ML toplevel.  The result is compiler dependent
  1773 and may fall back on "?" in certain situations.
  1774 
  1775 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1776 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1777 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1778 not work with the asynchronous Isar document model.
  1779 
  1780 * Configuration options now admit dynamic default values, depending on
  1781 the context or even global references.
  1782 
  1783 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1784 uses an efficient external library if available (for Poly/ML).
  1785 
  1786 * Renamed some important ML structures, while keeping the old names
  1787 for some time as aliases within the structure Legacy:
  1788 
  1789   OuterKeyword  ~>  Keyword
  1790   OuterLex      ~>  Token
  1791   OuterParse    ~>  Parse
  1792   OuterSyntax   ~>  Outer_Syntax
  1793   PrintMode     ~>  Print_Mode
  1794   SpecParse     ~>  Parse_Spec
  1795   ThyInfo       ~>  Thy_Info
  1796   ThyLoad       ~>  Thy_Load
  1797   ThyOutput     ~>  Thy_Output
  1798   TypeInfer     ~>  Type_Infer
  1799 
  1800 Note that "open Legacy" simplifies porting of sources, but forgetting
  1801 to remove it again will complicate porting again in the future.
  1802 
  1803 * Most operations that refer to a global context are named
  1804 accordingly, e.g. Simplifier.global_context or
  1805 ProofContext.init_global.  There are some situations where a global
  1806 context actually works, but under normal circumstances one needs to
  1807 pass the proper local context through the code!
  1808 
  1809 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1810 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1811 Pretty.pp argument to merge, which is absent in the standard
  1812 Theory_Data version.
  1813 
  1814 * Sorts.certify_sort and derived "cert" operations for types and terms
  1815 no longer minimize sorts.  Thus certification at the boundary of the
  1816 inference kernel becomes invariant under addition of class relations,
  1817 which is an important monotonicity principle.  Sorts are now minimized
  1818 in the syntax layer only, at the boundary between the end-user and the
  1819 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1820 explicitly in rare situations.
  1821 
  1822 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1823 emphasize that this is in no way a standard operation.
  1824 INCOMPATIBILITY.
  1825 
  1826 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1827 usual for resolution.  Rare INCOMPATIBILITY.
  1828 
  1829 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1830 to emphasize that these only work in a global situation (which is
  1831 quite rare).
  1832 
  1833 * Curried take and drop in library.ML; negative length is interpreted
  1834 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1835 
  1836 * Proof terms: type substitutions on proof constants now use canonical
  1837 order of type variables.  INCOMPATIBILITY for tools working with proof
  1838 terms.
  1839 
  1840 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1841 may no longer carry premises.  User-level specifications are
  1842 transformed accordingly by Thm.add_axiom/add_def.
  1843 
  1844 
  1845 *** System ***
  1846 
  1847 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1848 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1849 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1850 
  1851 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1852 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1853 respectively.
  1854 
  1855 * Old lib/scripts/polyml-platform is superseded by the
  1856 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1857 variant, even on a 64 bit machine.  The following example setting
  1858 prefers 64 bit if available:
  1859 
  1860   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1861 
  1862 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1863 Isabelle/Scala layer for advanced prover interaction and integration.
  1864 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1865 component.
  1866 
  1867 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1868 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1869 similar to the default assignment of the document preparation system
  1870 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1871 provides some operations for direct access to the font without asking
  1872 the user for manual installation.
  1873 
  1874 
  1875 
  1876 New in Isabelle2009-1 (December 2009)
  1877 -------------------------------------
  1878 
  1879 *** General ***
  1880 
  1881 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1882 one backslash should be used, even in ML sources.
  1883 
  1884 
  1885 *** Pure ***
  1886 
  1887 * Locale interpretation propagates mixins along the locale hierarchy.
  1888 The currently only available mixins are the equations used to map
  1889 local definitions to terms of the target domain of an interpretation.
  1890 
  1891 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1892 loc" to print all interpretations of locale "loc" in the theory.
  1893 Interpretations in proofs are not shown.
  1894 
  1895 * Thoroughly revised locales tutorial.  New section on conditional
  1896 interpretation.
  1897 
  1898 * On instantiation of classes, remaining undefined class parameters
  1899 are formally declared.  INCOMPATIBILITY.
  1900 
  1901 
  1902 *** Document preparation ***
  1903 
  1904 * New generalized style concept for printing terms: @{foo (style) ...}
  1905 instead of @{foo_style style ...}  (old form is still retained for
  1906 backward compatibility).  Styles can be also applied for
  1907 antiquotations prop, term_type and typeof.
  1908 
  1909 
  1910 *** HOL ***
  1911 
  1912 * New proof method "smt" for a combination of first-order logic with
  1913 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1914 fixed-size bitvectors; there is also basic support for higher-order
  1915 features (esp. lambda abstractions).  It is an incomplete decision
  1916 procedure based on external SMT solvers using the oracle mechanism;
  1917 for the SMT solver Z3, this method is proof-producing.  Certificates
  1918 are provided to avoid calling the external solvers solely for
  1919 re-checking proofs.  Due to a remote SMT service there is no need for
  1920 installing SMT solvers locally.  See src/HOL/SMT.
  1921 
  1922 * New commands to load and prove verification conditions generated by
  1923 the Boogie program verifier or derived systems (e.g. the Verifying C
  1924 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1925 
  1926 * New counterexample generator tool 'nitpick' based on the Kodkod
  1927 relational model finder.  See src/HOL/Tools/Nitpick and
  1928 src/HOL/Nitpick_Examples.
  1929 
  1930 * New commands 'code_pred' and 'values' to invoke the predicate
  1931 compiler and to enumerate values of inductive predicates.
  1932 
  1933 * A tabled implementation of the reflexive transitive closure.
  1934 
  1935 * New implementation of quickcheck uses generic code generator;
  1936 default generators are provided for all suitable HOL types, records
  1937 and datatypes.  Old quickcheck can be re-activated importing theory
  1938 Library/SML_Quickcheck.
  1939 
  1940 * New testing tool Mirabelle for automated proof tools.  Applies
  1941 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1942 every proof step in a theory.  To be used in batch mode via the
  1943 "mirabelle" utility.
  1944 
  1945 * New proof method "sos" (sum of squares) for nonlinear real
  1946 arithmetic (originally due to John Harison). It requires theory
  1947 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1948 works well in practice on quantifier-free real arithmetic with +, -,
  1949 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1950 inequalities between polynomials.  It makes use of external
  1951 semidefinite programming solvers.  Method "sos" generates a
  1952 certificate that can be pasted into the proof thus avoiding the need
  1953 to call an external tool every time the proof is checked.  See
  1954 src/HOL/Library/Sum_Of_Squares.
  1955 
  1956 * New method "linarith" invokes existing linear arithmetic decision
  1957 procedure only.
  1958 
  1959 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1960 
  1961 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1962 Causes full type information to be output to the ATPs.  This slows
  1963 ATPs down considerably but eliminates a source of unsound "proofs"
  1964 that fail later.
  1965 
  1966 * New method "metisFT": A version of metis that uses full type
  1967 information in order to avoid failures of proof reconstruction.
  1968 
  1969 * New evaluator "approximate" approximates an real valued term using
  1970 the same method as the approximation method.
  1971 
  1972 * Method "approximate" now supports arithmetic expressions as
  1973 boundaries of intervals and implements interval splitting and Taylor
  1974 series expansion.
  1975 
  1976 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1977 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1978 
  1979 * New theory SupInf of the supremum and infimum operators for sets of
  1980 reals.
  1981 
  1982 * New theory Probability, which contains a development of measure
  1983 theory, eventually leading to Lebesgue integration and probability.
  1984 
  1985 * Extended Multivariate Analysis to include derivation and Brouwer's
  1986 fixpoint theorem.
  1987 
  1988 * Reorganization of number theory, INCOMPATIBILITY:
  1989   - new number theory development for nat and int, in theories Divides
  1990     and GCD as well as in new session Number_Theory
  1991   - some constants and facts now suffixed with _nat and _int
  1992     accordingly
  1993   - former session NumberTheory now named Old_Number_Theory, including
  1994     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1995   - moved theory Pocklington from src/HOL/Library to
  1996     src/HOL/Old_Number_Theory
  1997 
  1998 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1999 lcm of finite and infinite sets. It is shown that they form a complete
  2000 lattice.
  2001 
  2002 * Class semiring_div requires superclass no_zero_divisors and proof of
  2003 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2004 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2005 generalized to class semiring_div, subsuming former theorems
  2006 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2007 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2008 INCOMPATIBILITY.
  2009 
  2010 * Refinements to lattice classes and sets:
  2011   - less default intro/elim rules in locale variant, more default
  2012     intro/elim rules in class variant: more uniformity
  2013   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2014     le_inf_iff
  2015   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2016     sup_aci)
  2017   - renamed ACI to inf_sup_aci
  2018   - new class "boolean_algebra"
  2019   - class "complete_lattice" moved to separate theory
  2020     "Complete_Lattice"; corresponding constants (and abbreviations)
  2021     renamed and with authentic syntax:
  2022     Set.Inf ~>    Complete_Lattice.Inf
  2023     Set.Sup ~>    Complete_Lattice.Sup
  2024     Set.INFI ~>   Complete_Lattice.INFI
  2025     Set.SUPR ~>   Complete_Lattice.SUPR
  2026     Set.Inter ~>  Complete_Lattice.Inter
  2027     Set.Union ~>  Complete_Lattice.Union
  2028     Set.INTER ~>  Complete_Lattice.INTER
  2029     Set.UNION ~>  Complete_Lattice.UNION
  2030   - authentic syntax for
  2031     Set.Pow
  2032     Set.image
  2033   - mere abbreviations:
  2034     Set.empty               (for bot)
  2035     Set.UNIV                (for top)
  2036     Set.inter               (for inf, formerly Set.Int)
  2037     Set.union               (for sup, formerly Set.Un)
  2038     Complete_Lattice.Inter  (for Inf)
  2039     Complete_Lattice.Union  (for Sup)
  2040     Complete_Lattice.INTER  (for INFI)
  2041     Complete_Lattice.UNION  (for SUPR)
  2042   - object-logic definitions as far as appropriate
  2043 
  2044 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2045 Un_subset_iff are explicitly deleted as default simp rules; then also
  2046 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2047 deleted to achieve the desired effect.
  2048 
  2049 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2050 rules by default any longer; the same applies to min_max.inf_absorb1
  2051 etc.  INCOMPATIBILITY.
  2052 
  2053 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2054 pred_set_conv by default.  INCOMPATIBILITY.
  2055 
  2056 * Power operations on relations and functions are now one dedicated
  2057 constant "compow" with infix syntax "^^".  Power operation on
  2058 multiplicative monoids retains syntax "^" and is now defined generic
  2059 in class power.  INCOMPATIBILITY.
  2060 
  2061 * Relation composition "R O S" now has a more standard argument order:
  2062 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2063 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2064 break, since the O_assoc rule was not rewritten like this.  Fix using
  2065 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2066 
  2067 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2068 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2069 INCOMPATIBILITY.
  2070 
  2071 * Most rules produced by inductive and datatype package have mandatory
  2072 prefixes.  INCOMPATIBILITY.
  2073 
  2074 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2075 the attribute of the same name.  Each of the theorems in the list
  2076 DERIV_intros assumes composition with an additional function and
  2077 matches a variable to the derivative, which has to be solved by the
  2078 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2079 of most elementary terms.  Former Maclauren.DERIV_tac and
  2080 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2081 INCOMPATIBILITY.
  2082 
  2083 * Code generator attributes follow the usual underscore convention:
  2084     code_unfold     replaces    code unfold
  2085     code_post       replaces    code post
  2086     etc.
  2087   INCOMPATIBILITY.
  2088 
  2089 * Renamed methods:
  2090     sizechange -> size_change
  2091     induct_scheme -> induction_schema
  2092   INCOMPATIBILITY.
  2093 
  2094 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2095 INCOMPATIBILITY, use "undefined" directly.
  2096 
  2097 * Renamed theorems:
  2098     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2099     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2100     Suc_plus1 -> Suc_eq_plus1
  2101     *anti_sym -> *antisym*
  2102     vector_less_eq_def -> vector_le_def
  2103   INCOMPATIBILITY.
  2104 
  2105 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2106 INCOMPATIBILITY.
  2107 
  2108 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2109 INCOMPATIBILITY.
  2110 
  2111 
  2112 *** HOLCF ***
  2113 
  2114 * Theory Representable defines a class "rep" of domains that are
  2115 representable (via an ep-pair) in the universal domain type "udom".
  2116 Instances are provided for all type constructors defined in HOLCF.
  2117 
  2118 * The 'new_domain' command is a purely definitional version of the
  2119 domain package, for representable domains.  Syntax is identical to the
  2120 old domain package.  The 'new_domain' package also supports indirect
  2121 recursion using previously-defined type constructors.  See
  2122 src/HOLCF/ex/New_Domain.thy for examples.
  2123 
  2124 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2125 on the left-hand side of an equation, and then performs
  2126 simplification.  Rewriting is done using rules declared with the
  2127 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2128 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2129 
  2130 * The pattern-match compiler in 'fixrec' can now handle constructors
  2131 with HOL function types.  Pattern-match combinators for the Pair
  2132 constructor are pre-configured.
  2133 
  2134 * The 'fixrec' package now produces better fixed-point induction rules
  2135 for mutually-recursive definitions:  Induction rules have conclusions
  2136 of the form "P foo bar" instead of "P <foo, bar>".
  2137 
  2138 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2139 been renamed to "below".  The name "below" now replaces "less" in many
  2140 theorem names.  (Legacy theorem names using "less" are still supported
  2141 as well.)
  2142 
  2143 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2144 patterns can be used to generate strictness rules, or to make
  2145 functions more strict (much like the bang-patterns supported by the
  2146 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2147 examples.
  2148 
  2149 
  2150 *** ML ***
  2151 
  2152 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2153 errors and run-time exceptions, including detailed source positions.
  2154 
  2155 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2156 identified entries, with some additional information such as source
  2157 position, logical grouping etc.
  2158 
  2159 * Theory and context data is now introduced by the simplified and
  2160 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2161 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2162 copy operation) is still available for some time.
  2163 
  2164 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2165 provides a high-level programming interface to synchronized state
  2166 variables with atomic update.  This works via pure function
  2167 application within a critical section -- its runtime should be as
  2168 short as possible; beware of deadlocks if critical code is nested,
  2169 either directly or indirectly via other synchronized variables!
  2170 
  2171 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2172 wraps raw ML references, explicitly indicating their non-thread-safe
  2173 behaviour.  The Isar toplevel keeps this structure open, to
  2174 accommodate Proof General as well as quick and dirty interactive
  2175 experiments with references.
  2176 
  2177 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2178 parallel tactical reasoning.
  2179 
  2180 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2181 are similar to SUBPROOF, but are slightly more flexible: only the
  2182 specified parts of the subgoal are imported into the context, and the
  2183 body tactic may introduce new subgoals and schematic variables.
  2184 
  2185 * Old tactical METAHYPS, which does not observe the proof context, has
  2186 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2187 or Subgoal.FOCUS etc.
  2188 
  2189 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2190 functors have their own ML name space there is no point to mark them
  2191 separately.)  Minor INCOMPATIBILITY.
  2192 
  2193 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2194 
  2195 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2196 INCOMPATIBILITY.
  2197 
  2198 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2199 mode, which avoids critical setmp.
  2200 
  2201 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2202 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2203 Attrib/Method.setup introduced in Isabelle2009.
  2204 
  2205 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2206 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2207 last resort.  INCOMPATIBILITY.
  2208 
  2209 * Display.pretty_thm now requires a proper context (cf. former
  2210 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2211 or even Display.pretty_thm_without_context as last resort.
  2212 INCOMPATIBILITY.
  2213 
  2214 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2215 Syntax.pretty_typ/term directly, preferably with proper context
  2216 instead of global theory.
  2217 
  2218 
  2219 *** System ***
  2220 
  2221 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2222 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2223 usedir option -q.
  2224 
  2225 * Support for additional "Isabelle components" via etc/components, see
  2226 also the system manual.
  2227 
  2228 * The isabelle makeall tool now operates on all components with
  2229 IsaMakefile, not just hardwired "logics".
  2230 
  2231 * Removed "compress" option from isabelle-process and isabelle usedir;
  2232 this is always enabled.
  2233 
  2234 * Discontinued support for Poly/ML 4.x versions.
  2235 
  2236 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2237 on a given logic image.  This requires the lighttpd webserver and is
  2238 currently supported on Linux only.
  2239 
  2240 
  2241 
  2242 New in Isabelle2009 (April 2009)
  2243 --------------------------------
  2244 
  2245 *** General ***
  2246 
  2247 * Simplified main Isabelle executables, with less surprises on
  2248 case-insensitive file-systems (such as Mac OS).
  2249 
  2250   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2251     "isatool."
  2252 
  2253   - The former "isabelle" alias for "isabelle-process" has been
  2254     removed (should rarely occur to regular users).
  2255 
  2256   - The former "isabelle-interface" and its alias "Isabelle" have been
  2257     removed (interfaces are now regular Isabelle tools).
  2258 
  2259 Within scripts and make files, the Isabelle environment variables
  2260 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2261 respectively.  (The latter are still available as legacy feature.)
  2262 
  2263 The old isabelle-interface wrapper could react in confusing ways if
  2264 the interface was uninstalled or changed otherwise.  Individual
  2265 interface tool configuration is now more explicit, see also the
  2266 Isabelle system manual.  In particular, Proof General is now available
  2267 via "isabelle emacs".
  2268 
  2269 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2270 purge installed copies of Isabelle executables and re-run "isabelle
  2271 install -p ...", or use symlinks.
  2272 
  2273 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2274 old ~/isabelle, which was slightly non-standard and apt to cause
  2275 surprises on case-insensitive file-systems (such as Mac OS).
  2276 
  2277 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2278 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2279 care is required when using older releases of Isabelle.  Note that
  2280 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2281 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2282 
  2283 * Proofs of fully specified statements are run in parallel on
  2284 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2285 a regular 4-core machine, if the initial heap space is made reasonably
  2286 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2287 
  2288 * The main reference manuals ("isar-ref", "implementation", and
  2289 "system") have been updated and extended.  Formally checked references
  2290 as hyperlinks are now available uniformly.
  2291 
  2292 
  2293 *** Pure ***
  2294 
  2295 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2296 respects.  The most important changes are listed below.  See the
  2297 Tutorial on Locales ("locales" manual) for details.
  2298 
  2299 - In locale expressions, instantiation replaces renaming.  Parameters
  2300 must be declared in a for clause.  To aid compatibility with previous
  2301 parameter inheritance, in locale declarations, parameters that are not
  2302 'touched' (instantiation position "_" or omitted) are implicitly added
  2303 with their syntax at the beginning of the for clause.
  2304 
  2305 - Syntax from abbreviations and definitions in locales is available in
  2306 locale expressions and context elements.  The latter is particularly
  2307 useful in locale declarations.
  2308 
  2309 - More flexible mechanisms to qualify names generated by locale
  2310 expressions.  Qualifiers (prefixes) may be specified in locale
  2311 expressions, and can be marked as mandatory (syntax: "name!:") or
  2312 optional (syntax "name?:").  The default depends for plain "name:"
  2313 depends on the situation where a locale expression is used: in
  2314 commands 'locale' and 'sublocale' prefixes are optional, in
  2315 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2316 implicit qualifiers derived from the parameter names of a locale are
  2317 no longer generated.
  2318 
  2319 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2320 instantiation clause in "interpretation" and "interpret" (square
  2321 brackets) is no longer available.  Use locale expressions.
  2322 
  2323 - When converting proof scripts, mandatory qualifiers in
  2324 'interpretation' and 'interpret' should be retained by default, even
  2325 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2326 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2327 in locale expressions range over a single locale instance only.
  2328 
  2329 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2330 In existing theorem specifications replace the includes element by the
  2331 respective context elements of the included locale, omitting those
  2332 that are already present in the theorem specification.  Multiple
  2333 assume elements of a locale should be replaced by a single one
  2334 involving the locale predicate.  In the proof body, declarations (most
  2335 notably theorems) may be regained by interpreting the respective
  2336 locales in the proof context as required (command "interpret").
  2337 
  2338 If using "includes" in replacement of a target solely because the
  2339 parameter types in the theorem are not as general as in the target,
  2340 consider declaring a new locale with additional type constraints on
  2341 the parameters (context element "constrains").
  2342 
  2343 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2344 
  2345 - Locale interpretation commands no longer attempt to simplify goal.
  2346 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2347 methods intro_locales and unfold_locales to clarify.
  2348 
  2349 - Locale interpretation commands no longer accept interpretation
  2350 attributes.  INCOMPATIBILITY.
  2351 
  2352 * Class declaration: so-called "base sort" must not be given in import
  2353 list any longer, but is inferred from the specification.  Particularly
  2354 in HOL, write
  2355 
  2356     class foo = ...
  2357 
  2358 instead of
  2359 
  2360     class foo = type + ...
  2361 
  2362 * Class target: global versions of theorems stemming do not carry a
  2363 parameter prefix any longer.  INCOMPATIBILITY.
  2364 
  2365 * Class 'instance' command no longer accepts attached definitions.
  2366 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2367 
  2368 * Recovered hiding of consts, which was accidentally broken in
  2369 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2370 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2371 
  2372 * Slightly more coherent Pure syntax, with updated documentation in
  2373 isar-ref manual.  Removed locales meta_term_syntax and
  2374 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2375 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2376 directly in regular applications.
  2377 
  2378 * There is a new syntactic category "float_const" for signed decimal
  2379 fractions (e.g. 123.45 or -123.45).
  2380 
  2381 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2382 interface with 'setup' command instead.
  2383 
  2384 * Command 'local_setup' is similar to 'setup', but operates on a local
  2385 theory context.
  2386 
  2387 * The 'axiomatization' command now only works within a global theory
  2388 context.  INCOMPATIBILITY.
  2389 
  2390 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2391 hypotheses.  Sorts required in the course of reasoning need to be
  2392 covered by the constraints in the initial statement, completed by the
  2393 type instance information of the background theory.  Non-trivial sort
  2394 hypotheses, which rarely occur in practice, may be specified via
  2395 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2396 
  2397   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2398 
  2399 The result contains an implicit sort hypotheses as before --
  2400 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2401 normalization.
  2402 
  2403 * Generalized Isar history, with support for linear undo, direct state
  2404 addressing etc.
  2405 
  2406 * Changed defaults for unify configuration options:
  2407 
  2408   unify_trace_bound = 50 (formerly 25)
  2409   unify_search_bound = 60 (formerly 30)
  2410 
  2411 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2412 
  2413   a) On theory merge, the last set of code equations for a particular
  2414      constant is taken (in accordance with the policy applied by other
  2415      parts of the code generator framework).
  2416 
  2417   b) Code equations stemming from explicit declarations (e.g. code
  2418      attribute) gain priority over default code equations stemming
  2419      from definition, primrec, fun etc.
  2420 
  2421 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2422 
  2423 * Unified theorem tables for both code generators.  Thus [code
  2424 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2425 
  2426 * Command 'find_consts' searches for constants based on type and name
  2427 patterns, e.g.
  2428 
  2429     find_consts "_ => bool"
  2430 
  2431 By default, matching is against subtypes, but it may be restricted to
  2432 the whole type.  Searching by name is possible.  Multiple queries are
  2433 conjunctive and queries may be negated by prefixing them with a
  2434 hyphen:
  2435 
  2436     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2437 
  2438 * New 'find_theorems' criterion "solves" matches theorems that
  2439 directly solve the current goal (modulo higher-order unification).
  2440 
  2441 * Auto solve feature for main theorem statements: whenever a new goal
  2442 is stated, "find_theorems solves" is called; any theorems that could
  2443 solve the lemma directly are listed as part of the goal state.
  2444 Cf. associated options in Proof General Isabelle settings menu,
  2445 enabled by default, with reasonable timeout for pathological cases of
  2446 higher-order unification.
  2447 
  2448 
  2449 *** Document preparation ***
  2450 
  2451 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2452 demanding keyword 'by' and supporting the full method expression
  2453 syntax just like the Isar command 'by'.
  2454 
  2455 
  2456 *** HOL ***
  2457 
  2458 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2459 points Main and Complex_Main remain as before.
  2460 
  2461 * Logic image HOL-Plain provides a minimal HOL with the most important
  2462 tools available (inductive, datatype, primrec, ...).  This facilitates
  2463 experimentation and tool development.  Note that user applications
  2464 (and library theories) should never refer to anything below theory
  2465 Main, as before.
  2466 
  2467 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2468 experimentation due to shorter build times.
  2469 
  2470 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2471 were previously part of former HOL-Complex.  Entry point Hyperreal
  2472 remains valid, but theories formerly using Complex_Main should now use
  2473 new entry point Hypercomplex.
  2474 
  2475 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2476 Posix processes.  Avoids potentially expensive forking of the ML
  2477 process.  New thread-based implementation also works on non-Unix
  2478 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2479 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2480 commands are covered in the isar-ref manual.
  2481 
  2482 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2483 sledgehammer without local ATP installation (Vampire etc.). Other
  2484 provers may be included via suitable ML wrappers, see also
  2485 src/HOL/ATP_Linkup.thy.
  2486 
  2487 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2488 menu.
  2489 
  2490 * The metis method no longer fails because the theorem is too trivial
  2491 (contains the empty clause).
  2492 
  2493 * The metis method now fails in the usual manner, rather than raising
  2494 an exception, if it determines that it cannot prove the theorem.
  2495 
  2496 * Method "coherent" implements a prover for coherent logic (see also
  2497 src/Tools/coherent.ML).
  2498 
  2499 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2500 "undefined" is the right choice to replace "arbitrary", though
  2501 logically there is no difference.  INCOMPATIBILITY.
  2502 
  2503 * Command "value" now integrates different evaluation mechanisms.  The
  2504 result of the first successful evaluation mechanism is printed.  In
  2505 square brackets a particular named evaluation mechanisms may be
  2506 specified (currently, [SML], [code] or [nbe]).  See further
  2507 src/HOL/ex/Eval_Examples.thy.
  2508 
  2509 * Normalization by evaluation now allows non-leftlinear equations.
  2510 Declare with attribute [code nbe].
  2511 
  2512 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2513 as the structured Isar versions "cases" and "induct", cf. the
  2514 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2515 are now presented as a list of individual projections
  2516 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2517 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2518 rare situations a different rule is selected --- notably nested tuple
  2519 elimination instead of former prod.exhaust: use explicit (case_tac t
  2520 rule: prod.exhaust) here.
  2521 
  2522 * Attributes "cases", "induct", "coinduct" support "del" option.
  2523 
  2524 * Removed fact "case_split_thm", which duplicates "case_split".
  2525 
  2526 * The option datatype has been moved to a new theory Option.  Renamed
  2527 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2528 
  2529 * New predicate "strict_mono" classifies strict functions on partial
  2530 orders.  With strict functions on linear orders, reasoning about
  2531 (in)equalities is facilitated by theorems "strict_mono_eq",
  2532 "strict_mono_less_eq" and "strict_mono_less".
  2533 
  2534 * Some set operations are now proper qualified constants with
  2535 authentic syntax.  INCOMPATIBILITY:
  2536 
  2537     op Int ~>   Set.Int
  2538     op Un ~>    Set.Un
  2539     INTER ~>    Set.INTER
  2540     UNION ~>    Set.UNION
  2541     Inter ~>    Set.Inter
  2542     Union ~>    Set.Union
  2543     {} ~>       Set.empty
  2544     UNIV ~>     Set.UNIV
  2545 
  2546 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2547 theory Set.
  2548 
  2549 * Auxiliary class "itself" has disappeared -- classes without any
  2550 parameter are treated as expected by the 'class' command.
  2551 
  2552 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2553 
  2554 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2555 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2556 
  2557 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2558 method "approximation".  It proves formulas on real values by using
  2559 interval arithmetic.  In the formulas are also the transcendental
  2560 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2561 allowed. For examples see
  2562 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2563 
  2564 * Theory "Reflection" now resides in HOL/Library.
  2565 
  2566 * Entry point to Word library now simply named "Word".
  2567 INCOMPATIBILITY.
  2568 
  2569 * Made source layout more coherent with logical distribution
  2570 structure:
  2571 
  2572     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2573     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2574     src/HOL/Library/GCD.thy ~> src/HOL/
  2575     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2576     src/HOL/Library/Parity.thy ~> src/HOL/
  2577     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2578     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2579     src/HOL/Real/Lubs.thy ~> src/HOL/
  2580     src/HOL/Real/PReal.thy ~> src/HOL/
  2581     src/HOL/Real/Rational.thy ~> src/HOL/
  2582     src/HOL/Real/RComplete.thy ~> src/HOL/
  2583     src/HOL/Real/RealDef.thy ~> src/HOL/
  2584     src/HOL/Real/RealPow.thy ~> src/HOL/
  2585     src/HOL/Real/Real.thy ~> src/HOL/
  2586     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2587     src/HOL/Complex/Complex.thy ~> src/HOL/
  2588     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2589     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2590     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2591     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2592     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2593     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2594     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2595     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2596     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2597     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2598     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2599     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2600     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2601     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2602     src/HOL/Real/Float ~> src/HOL/Library/
  2603     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2604     src/HOL/Real/RealVector.thy ~> src/HOL/
  2605 
  2606     src/HOL/arith_data.ML ~> src/HOL/Tools
  2607     src/HOL/hologic.ML ~> src/HOL/Tools
  2608     src/HOL/simpdata.ML ~> src/HOL/Tools
  2609     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2610     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2611     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2612     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2613     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2614     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2615     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2616 
  2617     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2618     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2619     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2620     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2621     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2622     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2623 
  2624 * If methods "eval" and "evaluation" encounter a structured proof
  2625 state with !!/==>, only the conclusion is evaluated to True (if
  2626 possible), avoiding strange error messages.
  2627 
  2628 * Method "sizechange" automates termination proofs using (a
  2629 modification of) the size-change principle.  Requires SAT solver.  See
  2630 src/HOL/ex/Termination.thy for examples.
  2631 
  2632 * Simplifier: simproc for let expressions now unfolds if bound
  2633 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2634 
  2635 * Method "arith": Linear arithmetic now ignores all inequalities when
  2636 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2637 
  2638 * New attribute "arith" for facts that should always be used
  2639 automatically by arithmetic. It is intended to be used locally in
  2640 proofs, e.g.
  2641 
  2642   assumes [arith]: "x > 0"
  2643 
  2644 Global usage is discouraged because of possible performance impact.
  2645 
  2646 * New classes "top" and "bot" with corresponding operations "top" and
  2647 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2648 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2649 
  2650 * Changed definition lemma "less_fun_def" in order to provide an
  2651 instance for preorders on functions; use lemma "less_le" instead.
  2652 INCOMPATIBILITY.
  2653 
  2654 * Theory Orderings: class "wellorder" moved here, with explicit
  2655 induction rule "less_induct" as assumption.  For instantiation of
  2656 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2657 INCOMPATIBILITY.
  2658 
  2659 * Theory Orderings: added class "preorder" as superclass of "order".
  2660 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2661 etc. slightly changed.  Some theorems named order_class.* now named
  2662 preorder_class.*.
  2663 
  2664 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2665 "diag" to "Id_on".
  2666 
  2667 * Theory Finite_Set: added a new fold combinator of type
  2668 
  2669   ('a => 'b => 'b) => 'b => 'a set => 'b
  2670 
  2671 Occasionally this is more convenient than the old fold combinator
  2672 which is now defined in terms of the new one and renamed to
  2673 fold_image.
  2674 
  2675 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2676 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2677 extended with further lemmas!).  At the moment both still exist but
  2678 the former will disappear at some point.
  2679 
  2680 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2681 class recpower.  Type-specific simp rules for various recpower types
  2682 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2683 
  2684 rat_power_0    -> power_0
  2685 rat_power_Suc  -> power_Suc
  2686 realpow_0      -> power_0
  2687 realpow_Suc    -> power_Suc
  2688 complexpow_0   -> power_0
  2689 complexpow_Suc -> power_Suc
  2690 power_poly_0   -> power_0
  2691 power_poly_Suc -> power_Suc
  2692 
  2693 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2694 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2695 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2696 of lemmas from Divides has been generalized from nat to class
  2697 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2698 renames resulting from duplicate elimination:
  2699 
  2700     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2701     zero_dvd_iff ~>         dvd_0_left_iff
  2702     dvd_0 ~>                dvd_0_right
  2703     DIVISION_BY_ZERO_DIV ~> div_by_0
  2704     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2705     mult_div ~>             div_mult_self2_is_id
  2706     mult_mod ~>             mod_mult_self2_is_0
  2707 
  2708 * Theory IntDiv: removed many lemmas that are instances of class-based
  2709 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2710 rename old lemmas as follows:
  2711 
  2712 dvd_diff               -> nat_dvd_diff
  2713 dvd_zminus_iff         -> dvd_minus_iff
  2714 mod_add1_eq            -> mod_add_eq
  2715 mod_mult1_eq           -> mod_mult_right_eq
  2716 mod_mult1_eq'          -> mod_mult_left_eq
  2717 mod_mult_distrib_mod   -> mod_mult_eq
  2718 nat_mod_add_left_eq    -> mod_add_left_eq
  2719 nat_mod_add_right_eq   -> mod_add_right_eq
  2720 nat_mod_div_trivial    -> mod_div_trivial
  2721 nat_mod_mod_trivial    -> mod_mod_trivial
  2722 zdiv_zadd_self1        -> div_add_self1
  2723 zdiv_zadd_self2        -> div_add_self2
  2724 zdiv_zmult_self1       -> div_mult_self2_is_id
  2725 zdiv_zmult_self2       -> div_mult_self1_is_id
  2726 zdvd_triv_left         -> dvd_triv_left
  2727 zdvd_triv_right        -> dvd_triv_right
  2728 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2729 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2730 zmod_zadd_left_eq      -> mod_add_left_eq
  2731 zmod_zadd_right_eq     -> mod_add_right_eq
  2732 zmod_zadd_self1        -> mod_add_self1
  2733 zmod_zadd_self2        -> mod_add_self2
  2734 zmod_zadd1_eq          -> mod_add_eq
  2735 zmod_zdiff1_eq         -> mod_diff_eq
  2736 zmod_zdvd_zmod         -> mod_mod_cancel
  2737 zmod_zmod_cancel       -> mod_mod_cancel
  2738 zmod_zmult_self1       -> mod_mult_self2_is_0
  2739 zmod_zmult_self2       -> mod_mult_self1_is_0
  2740 zmod_1                 -> mod_by_1
  2741 zdiv_1                 -> div_by_1
  2742 zdvd_abs1              -> abs_dvd_iff
  2743 zdvd_abs2              -> dvd_abs_iff
  2744 zdvd_refl              -> dvd_refl
  2745 zdvd_trans             -> dvd_trans
  2746 zdvd_zadd              -> dvd_add
  2747 zdvd_zdiff             -> dvd_diff
  2748 zdvd_zminus_iff        -> dvd_minus_iff
  2749 zdvd_zminus2_iff       -> minus_dvd_iff
  2750 zdvd_zmultD            -> dvd_mult_right
  2751 zdvd_zmultD2           -> dvd_mult_left
  2752 zdvd_zmult_mono        -> mult_dvd_mono
  2753 zdvd_0_right           -> dvd_0_right
  2754 zdvd_0_left            -> dvd_0_left_iff
  2755 zdvd_1_left            -> one_dvd
  2756 zminus_dvd_iff         -> minus_dvd_iff
  2757 
  2758 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2759 
  2760 * The real numbers offer decimal input syntax: 12.34 is translated
  2761 into 1234/10^2. This translation is not reversed upon output.
  2762 
  2763 * Theory Library/Polynomial defines an abstract type 'a poly of
  2764 univariate polynomials with coefficients of type 'a.  In addition to
  2765 the standard ring operations, it also supports div and mod.  Code
  2766 generation is also supported, using list-style constructors.
  2767 
  2768 * Theory Library/Inner_Product defines a class of real_inner for real
  2769 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2770 => real.  Class real_inner is a subclass of real_normed_vector from
  2771 theory RealVector.
  2772 
  2773 * Theory Library/Product_Vector provides instances for the product
  2774 type 'a * 'b of several classes from RealVector and Inner_Product.
  2775 Definitions of addition, subtraction, scalar multiplication, norms,
  2776 and inner products are included.
  2777 
  2778 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2779 addition to the field operations, numerals and case syntax are also
  2780 supported.
  2781 
  2782 * Theory Library/Diagonalize provides constructive version of Cantor's
  2783 first diagonalization argument.
  2784 
  2785 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2786 zlcm (for int); carried together from various gcd/lcm developements in
  2787 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2788 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2789 may recover tupled syntax as follows:
  2790 
  2791     hide (open) const gcd
  2792     abbreviation gcd where
  2793       "gcd == (%(a, b). GCD.gcd a b)"
  2794     notation (output)
  2795       GCD.gcd ("gcd '(_, _')")
  2796 
  2797 The same works for lcm, zgcd, zlcm.
  2798 
  2799 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2800 instantiations for algebraic structures.  Removed some duplicate
  2801 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2802 
  2803 * ML antiquotation @{code} takes a constant as argument and generates
  2804 corresponding code in background and inserts name of the corresponding
  2805 resulting ML value/function/datatype constructor binding in place.
  2806 All occurrences of @{code} with a single ML block are generated
  2807 simultaneously.  Provides a generic and safe interface for
  2808 instrumentalizing code generation.  See
  2809 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2810 In future you ought to refrain from ad-hoc compiling generated SML
  2811 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2812 cannot refer to constants for which user-defined serializations are
  2813 set.  Refer to the corresponding ML counterpart directly in that
  2814 cases.
  2815 
  2816 * Command 'rep_datatype': instead of theorem names the command now
  2817 takes a list of terms denoting the constructors of the type to be
  2818 represented as datatype.  The characteristic theorems have to be
  2819 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2820 have disappeared in favour of existing ones:
  2821 
  2822     unit_induct                 ~> unit.induct
  2823     prod_induct                 ~> prod.induct
  2824     sum_induct                  ~> sum.induct
  2825     Suc_Suc_eq                  ~> nat.inject
  2826     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2827 
  2828 
  2829 *** HOL-Algebra ***
  2830 
  2831 * New locales for orders and lattices where the equivalence relation
  2832 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2833 locales use a record structure with field eq for the equivalence.
  2834 
  2835 * New theory of factorial domains.
  2836 
  2837 * Units_l_inv and Units_r_inv are now simp rules by default.
  2838 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2839 and/or r_inv will now also require deletion of these lemmas.
  2840 
  2841 * Renamed the following theorems, INCOMPATIBILITY:
  2842 
  2843 UpperD ~> Upper_memD
  2844 LowerD ~> Lower_memD
  2845 least_carrier ~> least_closed
  2846 greatest_carrier ~> greatest_closed
  2847 greatest_Lower_above ~> greatest_Lower_below
  2848 one_zero ~> carrier_one_zero
  2849 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2850 
  2851 
  2852 *** HOL-Nominal ***
  2853 
  2854 * Nominal datatypes can now contain type-variables.
  2855 
  2856 * Commands 'nominal_inductive' and 'equivariance' work with local
  2857 theory targets.
  2858 
  2859 * Nominal primrec can now works with local theory targets and its
  2860 specification syntax now conforms to the general format as seen in
  2861 'inductive' etc.
  2862 
  2863 * Method "perm_simp" honours the standard simplifier attributes
  2864 (no_asm), (no_asm_use) etc.
  2865 
  2866 * The new predicate #* is defined like freshness, except that on the
  2867 left hand side can be a set or list of atoms.
  2868 
  2869 * Experimental command 'nominal_inductive2' derives strong induction
  2870 principles for inductive definitions.  In contrast to
  2871 'nominal_inductive', which can only deal with a fixed number of
  2872 binders, it can deal with arbitrary expressions standing for sets of
  2873 atoms to be avoided.  The only inductive definition we have at the
  2874 moment that needs this generalisation is the typing rule for Lets in
  2875 the algorithm W:
  2876 
  2877  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2878  -----------------------------------------------------------------
  2879          Gamma |- Let x be t1 in t2 : T2
  2880 
  2881 In this rule one wants to avoid all the binders that are introduced by
  2882 "close Gamma T1".  We are looking for other examples where this
  2883 feature might be useful.  Please let us know.
  2884 
  2885 
  2886 *** HOLCF ***
  2887 
  2888 * Reimplemented the simplification procedure for proving continuity
  2889 subgoals.  The new simproc is extensible; users can declare additional
  2890 continuity introduction rules with the attribute [cont2cont].
  2891 
  2892 * The continuity simproc now uses a different introduction rule for
  2893 solving continuity subgoals on terms with lambda abstractions.  In
  2894 some rare cases the new simproc may fail to solve subgoals that the
  2895 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2896 Potential INCOMPATIBILITY.
  2897 
  2898 * Command 'fixrec': specification syntax now conforms to the general
  2899 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2900 examples.  INCOMPATIBILITY.
  2901 
  2902 
  2903 *** ZF ***
  2904 
  2905 * Proof of Zorn's Lemma for partial orders.
  2906 
  2907 
  2908 *** ML ***
  2909 
  2910 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2911 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2912 depends on multithreading, so timouts will not work before Poly/ML
  2913 5.2.1!
  2914 
  2915 * High-level support for concurrent ML programming, see
  2916 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2917 particularly convenient to organize independent functional
  2918 computations.  The concept of "synchronized variables" provides a
  2919 higher-order interface for components with shared state, avoiding the
  2920 delicate details of mutexes and condition variables.  (Requires
  2921 Poly/ML 5.2.1 or later.)
  2922 
  2923 * ML bindings produced via Isar commands are stored within the Isar
  2924 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2925 become thread-safe and work with undo as expected (concerning
  2926 top-level bindings, not side-effects on global references).
  2927 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2928 compiler at runtime; really global bindings need to be given outside a
  2929 theory.  (Requires Poly/ML 5.2 or later.)
  2930 
  2931 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2932 context.  Top-level ML bindings are stored within the proof context in
  2933 a purely sequential fashion, disregarding the nested proof structure.
  2934 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2935 proof.  (Requires Poly/ML 5.2 or later.)
  2936 
  2937 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2938 and Method.setup, as well as Isar commands 'attribute_setup' and
  2939 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2940 existing code accordingly, or use plain 'setup' together with old
  2941 Method.add_method.
  2942 
  2943 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2944 to 'a -> thm, while results are always tagged with an authentic oracle
  2945 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2946 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2947 accordingly.  Note that extra performance may be gained by producing
  2948 the cterm carefully, avoiding slow Thm.cterm_of.
  2949 
  2950 * Simplified interface for defining document antiquotations via
  2951 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2952 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2953 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2954 examples.
  2955 
  2956 * More systematic treatment of long names, abstract name bindings, and
  2957 name space operations.  Basic operations on qualified names have been
  2958 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2959 Long_Name.append.  Old type bstring has been mostly replaced by
  2960 abstract type binding (see structure Binding), which supports precise
  2961 qualification by packages and local theory targets, as well as proper
  2962 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2963 bstring values into Binding.name, or better pass through abstract
  2964 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2965 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2966 
  2967 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2968 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2969 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2970 
  2971 * Disposed old type and term read functions (Sign.read_def_typ,
  2972 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2973 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2974 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2975 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2976 resort for legacy applications.
  2977 
  2978 * Disposed old declarations, tactics, tactic combinators that refer to
  2979 the simpset or claset of an implicit theory (such as Addsimps,
  2980 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2981 embedded ML text, or local_simpset_of with a proper context passed as
  2982 explicit runtime argument.
  2983 
  2984 * Rules and tactics that read instantiations (read_instantiate,
  2985 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2986 context, which is required for parsing and type-checking.  Moreover,
  2987 the variables are specified as plain indexnames, not string encodings
  2988 thereof.  INCOMPATIBILITY.
  2989 
  2990 * Generic Toplevel.add_hook interface allows to analyze the result of
  2991 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2992 for theorem dependency output of transactions resulting in a new
  2993 theory state.
  2994 
  2995 * ML antiquotations: block-structured compilation context indicated by
  2996 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2997 
  2998   @{binding name}                         - basic name binding
  2999   @{let ?pat = term}                      - term abbreviation (HO matching)
  3000   @{note name = fact}                     - fact abbreviation
  3001   @{thm fact}                             - singleton fact (with attributes)
  3002   @{thms fact}                            - general fact (with attributes)
  3003   @{lemma prop by method}                 - singleton goal
  3004   @{lemma prop by meth1 meth2}            - singleton goal
  3005   @{lemma prop1 ... propN by method}      - general goal
  3006   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3007   @{lemma (open) ...}                     - open derivation
  3008 
  3009 
  3010 *** System ***
  3011 
  3012 * The Isabelle "emacs" tool provides a specific interface to invoke
  3013 Proof General / Emacs, with more explicit failure if that is not
  3014 installed (the old isabelle-interface script silently falls back on
  3015 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3016 installation location of the Proof General distribution.
  3017 
  3018 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3019 the Isabelle process into a JVM/Scala application.  See
  3020 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3021 process wrapper has been discontinued.)
  3022 
  3023 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3024 
  3025 * Various status messages (with exact source position information) are
  3026 emitted, if proper markup print mode is enabled.  This allows
  3027 user-interface components to provide detailed feedback on internal
  3028 prover operations.
  3029 
  3030 
  3031 
  3032 New in Isabelle2008 (June 2008)
  3033 -------------------------------
  3034 
  3035 *** General ***
  3036 
  3037 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3038 and updated, with formally checked references as hyperlinks.
  3039 
  3040 * Theory loader: use_thy (and similar operations) no longer set the
  3041 implicit ML context, which was occasionally hard to predict and in
  3042 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3043 provides a proper context already.
  3044 
  3045 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3046 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3047 'use' within a theory file will do the job.
  3048 
  3049 * Name space merge now observes canonical order, i.e. the second space
  3050 is inserted into the first one, while existing entries in the first
  3051 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3052 swap theory imports.
  3053 
  3054 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3055 INCOMPATIBILITY in identifier syntax etc.
  3056 
  3057 * Outer syntax: string tokens no longer admit escaped white space,
  3058 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3059 white space without escapes.
  3060 
  3061 * Outer syntax: string tokens may contain arbitrary character codes
  3062 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3063 "foo_bar".
  3064 
  3065 
  3066 *** Pure ***
  3067 
  3068 * Context-dependent token translations.  Default setup reverts locally
  3069 fixed variables, and adds hilite markup for undeclared frees.
  3070 
  3071 * Unused theorems can be found using the new command 'unused_thms'.
  3072 There are three ways of invoking it:
  3073 
  3074 (1) unused_thms
  3075      Only finds unused theorems in the current theory.
  3076 
  3077 (2) unused_thms thy_1 ... thy_n -
  3078      Finds unused theorems in the current theory and all of its ancestors,
  3079      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3080 
  3081 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3082      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3083      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3084      their ancestors.
  3085 
  3086 In order to increase the readability of the list produced by
  3087 unused_thms, theorems that have been created by a particular instance
  3088 of a theory command such as 'inductive' or 'function' are considered
  3089 to belong to the same "group", meaning that if at least one theorem in
  3090 this group is used, the other theorems in the same group are no longer
  3091 reported as unused.  Moreover, if all theorems in the group are
  3092 unused, only one theorem in the group is displayed.
  3093 
  3094 Note that proof objects have to be switched on in order for
  3095 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3096 usually the case when using Proof General with the default settings).
  3097 
  3098 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3099 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3100 duplicate fact bindings, or even accidental fact duplications.  Note
  3101 that tools may maintain dynamically scoped facts systematically, using
  3102 PureThy.add_thms_dynamic.
  3103 
  3104 * Command 'hide' now allows to hide from "fact" name space as well.
  3105 
  3106 * Eliminated destructive theorem database, simpset, claset, and
  3107 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3108 update of theories within ML code.
  3109 
  3110 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3111 INCOMPATIBILITY, object-logics depending on former Pure require
  3112 additional setup PureThy.old_appl_syntax_setup; object-logics
  3113 depending on former CPure need to refer to Pure.
  3114 
  3115 * Commands 'use' and 'ML' are now purely functional, operating on
  3116 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3117 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3118 INCOMPATIBILITY.
  3119 
  3120 * Command 'setup': discontinued implicit version with ML reference.
  3121 
  3122 * Instantiation target allows for simultaneous specification of class
  3123 instance operations together with an instantiation proof.
  3124 Type-checking phase allows to refer to class operations uniformly.
  3125 See src/HOL/Complex/Complex.thy for an Isar example and
  3126 src/HOL/Library/Eval.thy for an ML example.
  3127 
  3128 * Indexing of literal facts: be more serious about including only
  3129 facts from the visible specification/proof context, but not the
  3130 background context (locale etc.).  Affects `prop` notation and method
  3131 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3132 situations.
  3133 
  3134 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3135 "(open)" option, which used to expose internal bound variables to the
  3136 proof text.
  3137 
  3138 * Isar statements: removed obsolete case "rule_context".
  3139 INCOMPATIBILITY, better use explicit fixes/assumes.
  3140 
  3141 * Locale proofs: default proof step now includes 'unfold_locales';
  3142 hence 'proof' without argument may be used to unfold locale
  3143 predicates.
  3144 
  3145 
  3146 *** Document preparation ***
  3147 
  3148 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3149 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3150 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3151 spot); renamed link color from "darkblue" to "linkcolor" (default
  3152 value unchanged, can be redefined via \definecolor); no longer sets
  3153 "a4paper" option (unnecessary or even intrusive).
  3154 
  3155 * Antiquotation @{lemma A method} proves proposition A by the given
  3156 method (either a method name or a method name plus (optional) method
  3157 arguments in parentheses) and prints A just like @{prop A}.
  3158 
  3159 
  3160 *** HOL ***
  3161 
  3162 * New primrec package.  Specification syntax conforms in style to
  3163 definition/function/....  No separate induction rule is provided.  The
  3164 "primrec" command distinguishes old-style and new-style specifications
  3165 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3166 When adjusting theories, beware: constants stemming from new-style
  3167 primrec specifications have authentic syntax.
  3168 
  3169 * Metis prover is now an order of magnitude faster, and also works
  3170 with multithreading.
  3171 
  3172 * Metis: the maximum number of clauses that can be produced from a
  3173 theorem is now given by the attribute max_clauses.  Theorems that
  3174 exceed this number are ignored, with a warning printed.
  3175 
  3176 * Sledgehammer no longer produces structured proofs by default. To
  3177 enable, declare [[sledgehammer_full = true]].  Attributes
  3178 reconstruction_modulus, reconstruction_sorts renamed
  3179 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3180 
  3181 * Method "induct_scheme" derives user-specified induction rules
  3182 from well-founded induction and completeness of patterns. This factors
  3183 out some operations that are done internally by the function package
  3184 and makes them available separately.  See
  3185 src/HOL/ex/Induction_Scheme.thy for examples.
  3186 
  3187 * More flexible generation of measure functions for termination
  3188 proofs: Measure functions can be declared by proving a rule of the
  3189 form "is_measure f" and giving it the [measure_function] attribute.
  3190 The "is_measure" predicate is logically meaningless (always true), and
  3191 just guides the heuristic.  To find suitable measure functions, the
  3192 termination prover sets up the goal "is_measure ?f" of the appropriate
  3193 type and generates all solutions by prolog-style backwards proof using
  3194 the declared rules.
  3195 
  3196 This setup also deals with rules like 
  3197 
  3198   "is_measure f ==> is_measure (list_size f)"
  3199 
  3200 which accommodates nested datatypes that recurse through lists.
  3201 Similar rules are predeclared for products and option types.
  3202 
  3203 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3204 
  3205   INCOMPATIBILITIES:
  3206 
  3207   - Definitions of overloaded constants on sets have to be replaced by
  3208     definitions on => and bool.
  3209 
  3210   - Some definitions of overloaded operators on sets can now be proved
  3211     using the definitions of the operators on => and bool.  Therefore,
  3212     the following theorems have been renamed:
  3213 
  3214       subset_def   -> subset_eq
  3215       psubset_def  -> psubset_eq
  3216       set_diff_def -> set_diff_eq
  3217       Compl_def    -> Compl_eq
  3218       Sup_set_def  -> Sup_set_eq
  3219       Inf_set_def  -> Inf_set_eq
  3220       sup_set_def  -> sup_set_eq
  3221       inf_set_def  -> inf_set_eq
  3222 
  3223   - Due to the incompleteness of the HO unification algorithm, some
  3224     rules such as subst may require manual instantiation, if some of
  3225     the unknowns in the rule is a set.
  3226 
  3227   - Higher order unification and forward proofs:
  3228     The proof pattern
  3229 
  3230       have "P (S::'a set)" <...>
  3231       then have "EX S. P S" ..
  3232 
  3233     no longer works (due to the incompleteness of the HO unification
  3234     algorithm) and must be replaced by the pattern
  3235 
  3236       have "EX S. P S"
  3237       proof
  3238         show "P S" <...>
  3239       qed
  3240 
  3241   - Calculational reasoning with subst (or similar rules):
  3242     The proof pattern
  3243 
  3244       have "P (S::'a set)" <...>
  3245       also have "S = T" <...>
  3246       finally have "P T" .
  3247 
  3248     no longer works (for similar reasons as the previous example) and
  3249     must be replaced by something like
  3250 
  3251       have "P (S::'a set)" <...>
  3252       moreover have "S = T" <...>
  3253       ultimately have "P T" by simp
  3254 
  3255   - Tactics or packages written in ML code:
  3256     Code performing pattern matching on types via
  3257 
  3258       Type ("set", [T]) => ...
  3259 
  3260     must be rewritten. Moreover, functions like strip_type or
  3261     binder_types no longer return the right value when applied to a
  3262     type of the form
  3263 
  3264       T1 => ... => Tn => U => bool
  3265 
  3266     rather than
  3267 
  3268       T1 => ... => Tn => U set
  3269 
  3270 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3271 Wellfounded_Relations to theory Wellfounded.
  3272 
  3273 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3274 
  3275 * Class finite no longer treats UNIV as class parameter.  Use class
  3276 enum from theory Library/Enum instead to achieve a similar effect.
  3277 INCOMPATIBILITY.
  3278 
  3279 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3280 and "Cons".  INCOMPATIBILITY.
  3281 
  3282 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3283 Potential INCOMPATIBILITY.
  3284 
  3285 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3286 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3287 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3288 
  3289 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3290 the same name in theory Orderings:
  3291 
  3292   less_trans
  3293   less_linear
  3294   le_imp_less_or_eq
  3295   le_less_trans
  3296   less_le_trans
  3297   less_not_sym
  3298   less_asym
  3299 
  3300 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3301 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3302 and different variable names.
  3303 
  3304 * Library/Option_ord.thy: Canonical order on option type.
  3305 
  3306 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3307 finite maps.
  3308 
  3309 * Library/Countable.thy: Type class for countable types.
  3310 
  3311 * Theory Int: The representation of numerals has changed.  The infix
  3312 operator BIT and the bit datatype with constructors B0 and B1 have
  3313 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3314 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3315 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3316 accordingly.
  3317 
  3318 * Theory Nat: definition of <= and < on natural numbers no longer
  3319 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3320 le_def and less_def have disappeared.  Consider lemmas not_less
  3321 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3322 
  3323 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3324 (whose purpose mainly is for various fold_set functionals) have been
  3325 abandoned in favor of the existing algebraic classes
  3326 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3327 lower_semilattice (resp. upper_semilattice) and linorder.
  3328 INCOMPATIBILITY.
  3329 
  3330 * Theory Transitive_Closure: induct and cases rules now declare proper
  3331 case_names ("base" and "step").  INCOMPATIBILITY.
  3332 
  3333 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3334 lattices.  The form set-specific version is available as
  3335 Inductive.lfp_ordinal_induct_set.
  3336 
  3337 * Renamed theorems "power.simps" to "power_int.simps".
  3338 INCOMPATIBILITY.
  3339 
  3340 * Class semiring_div provides basic abstract properties of semirings
  3341 with division and modulo operations.  Subsumes former class dvd_mod.
  3342 
  3343 * Merged theories IntDef, Numeral and IntArith into unified theory
  3344 Int.  INCOMPATIBILITY.
  3345 
  3346 * Theory Library/Code_Index: type "index" now represents natural
  3347 numbers rather than integers.  INCOMPATIBILITY.
  3348 
  3349 * New class "uminus" with operation "uminus" (split of from class
  3350 "minus" which now only has operation "minus", binary).
  3351 INCOMPATIBILITY.
  3352 
  3353 * Constants "card", "internal_split", "option_map" now with authentic
  3354 syntax.  INCOMPATIBILITY.
  3355 
  3356 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3357 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3358 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3359 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3360 Sup_set_def, le_def, less_def, option_map_def now with object
  3361 equality.  INCOMPATIBILITY.
  3362 
  3363 * Records. Removed K_record, and replaced it by pure lambda term
  3364 %x. c. The simplifier setup is now more robust against eta expansion.
  3365 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3366 
  3367 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3368 
  3369 * Library/ListVector: new theory of arithmetic vector operations.
  3370 
  3371 * Library/Order_Relation: new theory of various orderings as sets of
  3372 pairs.  Defines preorders, partial orders, linear orders and
  3373 well-orders on sets and on types.
  3374 
  3375 
  3376 *** ZF ***
  3377 
  3378 * Renamed some theories to allow to loading both ZF and HOL in the
  3379 same session:
  3380 
  3381   Datatype  -> Datatype_ZF
  3382   Inductive -> Inductive_ZF
  3383   Int       -> Int_ZF
  3384   IntDiv    -> IntDiv_ZF
  3385   Nat       -> Nat_ZF
  3386   List      -> List_ZF
  3387   Main      -> Main_ZF
  3388 
  3389 INCOMPATIBILITY: ZF theories that import individual theories below
  3390 Main might need to be adapted.  Regular theory Main is still
  3391 available, as trivial extension of Main_ZF.
  3392 
  3393 
  3394 *** ML ***
  3395 
  3396 * ML within Isar: antiquotation @{const name} or @{const
  3397 name(typargs)} produces statically-checked Const term.
  3398 
  3399 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3400 (of the same name).  Removed obsolete print command.
  3401 
  3402 * Removed obsolete "use_legacy_bindings" function.
  3403 
  3404 * The ``print mode'' is now a thread-local value derived from a global
  3405 template (the former print_mode reference), thus access becomes
  3406 non-critical.  The global print_mode reference is for session
  3407 management only; user-code should use print_mode_value,
  3408 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3409 
  3410 * Functions system/system_out provide a robust way to invoke external
  3411 shell commands, with propagation of interrupts (requires Poly/ML
  3412 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3413 
  3414 
  3415 *** System ***
  3416 
  3417 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3418 in accordance with Proof General 3.7, which prefers GNU emacs.
  3419 
  3420 * isatool tty runs Isabelle process with plain tty interaction;
  3421 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3422 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3423 
  3424 * isatool browser now works with Cygwin as well, using general
  3425 "javapath" function defined in Isabelle process environment.
  3426 
  3427 * YXML notation provides a simple and efficient alternative to
  3428 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3429 isatool yxml as described in the Isabelle system manual.
  3430 
  3431 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3432 provides general wrapper for managing an Isabelle process in a robust
  3433 fashion, with ``cooked'' output from stdin/stderr.
  3434 
  3435 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3436 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3437 
  3438 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3439 way of changing the user's settings is via
  3440 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3441 script.
  3442 
  3443 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3444 cores of the underlying machine, which is a good starting point for
  3445 optimal performance tuning.  The corresponding usedir option -M allows
  3446 "max" as an alias for "0".  WARNING: does not work on certain versions
  3447 of Mac OS (with Poly/ML 5.1).
  3448 
  3449 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3450 adverse effect of Isabelle flooding interactive front-ends (notably
  3451 ProofGeneral / XEmacs).
  3452 
  3453 
  3454 
  3455 New in Isabelle2007 (November 2007)
  3456 -----------------------------------
  3457 
  3458 *** General ***
  3459 
  3460 * More uniform information about legacy features, notably a
  3461 warning/error of "Legacy feature: ...", depending on the state of the
  3462 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3463 legacy features will disappear eventually.
  3464 
  3465 * Theory syntax: the header format ``theory A = B + C:'' has been
  3466 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3467 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3468 
  3469 * Theory syntax: the old non-Isar theory file format has been
  3470 discontinued altogether.  Note that ML proof scripts may still be used
  3471 with Isar theories; migration is usually quite simple with the ML
  3472 function use_legacy_bindings.  INCOMPATIBILITY.
  3473 
  3474 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3475 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3476 quotes.
  3477 
  3478 * Theory loader: be more serious about observing the static theory
  3479 header specifications (including optional directories), but not the
  3480 accidental file locations of previously successful loads.  The strict
  3481 update policy of former update_thy is now already performed by
  3482 use_thy, so the former has been removed; use_thys updates several
  3483 theories simultaneously, just as 'imports' within a theory header
  3484 specification, but without merging the results.  Potential
  3485 INCOMPATIBILITY: may need to refine theory headers and commands
  3486 ROOT.ML which depend on load order.
  3487 
  3488 * Theory loader: optional support for content-based file
  3489 identification, instead of the traditional scheme of full physical
  3490 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3491 (cf. the system manual).  The new scheme allows to work with
  3492 non-finished theories in persistent session images, such that source
  3493 files may be moved later on without requiring reloads.
  3494 
  3495 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3496 file (with the same base name as the theory) are considered a legacy
  3497 feature, which will disappear eventually. Even now, the theory loader
  3498 no longer maintains dependencies on such files.
  3499 
  3500 * Syntax: the scope for resolving ambiguities via type-inference is
  3501 now limited to individual terms, instead of whole simultaneous
  3502 specifications as before. This greatly reduces the complexity of the
  3503 syntax module and improves flexibility by separating parsing and
  3504 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3505 'fixes' etc.) are required in rare situations.
  3506 
  3507 * Syntax: constants introduced by new-style packages ('definition',
  3508 'abbreviation' etc.) are passed through the syntax module in
  3509 ``authentic mode''. This means that associated mixfix annotations
  3510 really stick to such constants, independently of potential name space
  3511 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3512 trees are represented slightly differently, may need to adapt syntax
  3513 translations accordingly. Use CONST marker in 'translations' and
  3514 @{const_syntax} antiquotation in 'parse_translation' etc.
  3515 
  3516 * Legacy goal package: reduced interface to the bare minimum required
  3517 to keep existing proof scripts running.  Most other user-level
  3518 functions are now part of the OldGoals structure, which is *not* open
  3519 by default (consider isatool expandshort before open OldGoals).
  3520 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3521 these tend to cause confusion about the actual goal (!) context being
  3522 used here, which is not necessarily the same as the_context().
  3523 
  3524 * Command 'find_theorems': supports "*" wild-card in "name:"
  3525 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3526 support a specific search form (see ProofGeneral/CHANGES).
  3527 
  3528 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3529 by default, which means that "prems" (and also "fixed variables") are
  3530 suppressed from proof state output.  Note that the ProofGeneral
  3531 settings mechanism allows to change and save options persistently, but
  3532 older versions of Isabelle will fail to start up if a negative prems
  3533 limit is imposed.
  3534 
  3535 * Local theory targets may be specified by non-nested blocks of
  3536 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3537 contain definitions, theorems etc., including any derived mechanism
  3538 that has been implemented on top of these primitives.  This concept
  3539 generalizes the existing ``theorem (in ...)'' towards more versatility
  3540 and scalability.
  3541 
  3542 * Proof General interface: proper undo of final 'end' command;
  3543 discontinued Isabelle/classic mode (ML proof scripts).
  3544 
  3545 
  3546 *** Document preparation ***
  3547 
  3548 * Added antiquotation @{theory name} which prints the given name,
  3549 after checking that it refers to a valid ancestor theory in the
  3550 current context.
  3551 
  3552 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3553 check the given source text as ML type/structure, printing verbatim.
  3554 
  3555 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3556 "c args == rhs" given in the current context.  (Any number of
  3557 arguments may be given on the LHS.)
  3558 
  3559 
  3560 *** Pure ***
  3561 
  3562 * The 'class' package offers a combination of axclass and locale to
  3563 achieve Haskell-like type classes in Isabelle.  Definitions and
  3564 theorems within a class context produce both relative results (with
  3565 implicit parameters according to the locale context), and polymorphic
  3566 constants with qualified polymorphism (according to the class
  3567 context).  Within the body context of a 'class' target, a separate
  3568 syntax layer ("user space type system") takes care of converting
  3569 between global polymorphic consts and internal locale representation.
  3570 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3571 "isatool doc classes" provides a tutorial.
  3572 
  3573 * Generic code generator framework allows to generate executable
  3574 code for ML and Haskell (including Isabelle classes).  A short usage
  3575 sketch:
  3576 
  3577     internal compilation:
  3578         export_code <list of constants (term syntax)> in SML
  3579     writing SML code to a file:
  3580         export_code <list of constants (term syntax)> in SML <filename>
  3581     writing OCaml code to a file:
  3582         export_code <list of constants (term syntax)> in OCaml <filename>
  3583     writing Haskell code to a bunch of files:
  3584         export_code <list of constants (term syntax)> in Haskell <filename>
  3585 
  3586     evaluating closed propositions to True/False using code generation:
  3587         method ``eval''
  3588 
  3589 Reasonable default setup of framework in HOL.
  3590 
  3591 Theorem attributs for selecting and transforming function equations theorems:
  3592 
  3593     [code fun]:        select a theorem as function equation for a specific constant
  3594     [code fun del]:    deselect a theorem as function equation for a specific constant
  3595     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3596     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3597 
  3598 User-defined serializations (target in {SML, OCaml, Haskell}):
  3599 
  3600     code_const <and-list of constants (term syntax)>
  3601       {(target) <and-list of const target syntax>}+
  3602 
  3603     code_type <and-list of type constructors>
  3604       {(target) <and-list of type target syntax>}+
  3605 
  3606     code_instance <and-list of instances>
  3607       {(target)}+
  3608         where instance ::= <type constructor> :: <class>
  3609 
  3610     code_class <and_list of classes>
  3611       {(target) <and-list of class target syntax>}+
  3612         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3613 
  3614 code_instance and code_class only are effective to target Haskell.
  3615 
  3616 For example usage see src/HOL/ex/Codegenerator.thy and
  3617 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3618 generation from Isabelle/HOL theories is available via "isatool doc
  3619 codegen".
  3620 
  3621 * Code generator: consts in 'consts_code' Isar commands are now
  3622 referred to by usual term syntax (including optional type
  3623 annotations).
  3624 
  3625 * Command 'no_translations' removes translation rules from theory
  3626 syntax.
  3627 
  3628 * Overloaded definitions are now actually checked for acyclic
  3629 dependencies.  The overloading scheme is slightly more general than
  3630 that of Haskell98, although Isabelle does not demand an exact
  3631 correspondence to type class and instance declarations.
  3632 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3633 exotic versions of overloading -- at the discretion of the user!
  3634 
  3635 Polymorphic constants are represented via type arguments, i.e. the
  3636 instantiation that matches an instance against the most general
  3637 declaration given in the signature.  For example, with the declaration
  3638 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3639 as c(nat).  Overloading is essentially simultaneous structural
  3640 recursion over such type arguments.  Incomplete specification patterns
  3641 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3642 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3643 Command 'print_theory' outputs the normalized system of recursive
  3644 equations, see section "definitions".
  3645 
  3646 * Configuration options are maintained within the theory or proof
  3647 context (with name and type bool/int/string), providing a very simple
  3648 interface to a poor-man's version of general context data.  Tools may
  3649 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3650 these values using Config.get etc.  Users may change options via an
  3651 associated attribute of the same name.  This form of context
  3652 declaration works particularly well with commands 'declare' or
  3653 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3654 very easy to avoid global references, which would not observe Isar
  3655 toplevel undo/redo and fail to work with multithreading.
  3656 
  3657 Various global ML references of Pure and HOL have been turned into
  3658 configuration options:
  3659 
  3660   Unify.search_bound		unify_search_bound
  3661   Unify.trace_bound		unify_trace_bound
  3662   Unify.trace_simp		unify_trace_simp
  3663   Unify.trace_types		unify_trace_types
  3664   Simplifier.simp_depth_limit	simp_depth_limit
  3665   Blast.depth_limit		blast_depth_limit
  3666   DatatypeProp.dtK		datatype_distinctness_limit
  3667   fast_arith_neq_limit  	fast_arith_neq_limit
  3668   fast_arith_split_limit	fast_arith_split_limit
  3669 
  3670 * Named collections of theorems may be easily installed as context
  3671 data using the functor NamedThmsFun (see also
  3672 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3673 attributes; there is also a toplevel print command.  This facility is
  3674 just a common case of general context data, which is the preferred way
  3675 for anything more complex than just a list of facts in canonical
  3676 order.
  3677 
  3678 * Isar: command 'declaration' augments a local theory by generic
  3679 declaration functions written in ML.  This enables arbitrary content
  3680 being added to the context, depending on a morphism that tells the
  3681 difference of the original declaration context wrt. the application
  3682 context encountered later on.
  3683 
  3684 * Isar: proper interfaces for simplification procedures.  Command
  3685 'simproc_setup' declares named simprocs (with match patterns, and body
  3686 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3687 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3688 
  3689 * Isar: an extra pair of brackets around attribute declarations
  3690 abbreviates a theorem reference involving an internal dummy fact,
  3691 which will be ignored later --- only the effect of the attribute on
  3692 the background context will persist.  This form of in-place
  3693 declarations is particularly useful with commands like 'declare' and
  3694 'using', for example ``have A using [[simproc a]] by simp''.
  3695 
  3696 * Isar: method "assumption" (and implicit closing of subproofs) now
  3697 takes simple non-atomic goal assumptions into account: after applying
  3698 an assumption as a rule the resulting subgoals are solved by atomic
  3699 assumption steps.  This is particularly useful to finish 'obtain'
  3700 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3701 without referring to the original premise "!!x. P x ==> thesis" in the
  3702 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3703 more permissive.
  3704 
  3705 * Isar: implicit use of prems from the Isar proof context is
  3706 considered a legacy feature.  Common applications like ``have A .''
  3707 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3708 referencing facts explicitly here improves readability and
  3709 maintainability of proof texts.
  3710 
  3711 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3712 the obtained context from the course of reasoning!  For example:
  3713 
  3714   assume "EX x y. A x & B y"   -- "any previous fact"
  3715   then guess x and y by clarify
  3716 
  3717 This technique is potentially adventurous, depending on the facts and
  3718 proof tools being involved here.
  3719 
  3720 * Isar: known facts from the proof context may be specified as literal
  3721 propositions, using ASCII back-quote syntax.  This works wherever
  3722 named facts used to be allowed so far, in proof commands, proof
  3723 methods, attributes etc.  Literal facts are retrieved from the context
  3724 according to unification of type and term parameters.  For example,
  3725 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3726 theorems in the current context, then these are valid literal facts:
  3727 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3728 
  3729 There is also a proof method "fact" which does the same composition
  3730 for explicit goal states, e.g. the following proof texts coincide with
  3731 certain special cases of literal facts:
  3732 
  3733   have "A" by fact                 ==  note `A`
  3734   have "A ==> B" by fact           ==  note `A ==> B`
  3735   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3736   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3737 
  3738 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3739 outer syntax.  Thus symbolic identifiers may be used without
  3740 additional white space in declarations like this: ``assume *: A''.
  3741 
  3742 * Isar: 'print_facts' prints all local facts of the current context,
  3743 both named and unnamed ones.
  3744 
  3745 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3746 
  3747   def x == "t" and y == "u"
  3748 
  3749 * Isar: added command 'unfolding', which is structurally similar to
  3750 'using', but affects both the goal state and facts by unfolding given
  3751 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3752 'unfolded' attribute may be replaced by first-class proof text.
  3753 
  3754 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3755 and command 'unfolding' now all support object-level equalities
  3756 (potentially conditional).  The underlying notion of rewrite rule is
  3757 analogous to the 'rule_format' attribute, but *not* that of the
  3758 Simplifier (which is usually more generous).
  3759 
  3760 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3761 premises of a theorem by n. Useful in conjunction with drule.
  3762 
  3763 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3764 method expression within a sandbox consisting of the first N
  3765 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3766 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3767 simplifies all new goals that emerge from applying rule foo to the
  3768 originally first one.
  3769 
  3770 * Isar: schematic goals are no longer restricted to higher-order
  3771 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3772 expected.
  3773 
  3774 * Isar: the conclusion of a long theorem statement is now either
  3775 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3776 (essentially a disjunction of cases with local parameters and
  3777 assumptions).  The latter allows to express general elimination rules
  3778 adequately; in this notation common elimination rules look like this:
  3779 
  3780   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3781     assumes "EX x. P x"
  3782     obtains x where "P x"
  3783 
  3784   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3785     assumes "A & B"
  3786     obtains A and B
  3787 
  3788   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3789     assumes "A | B"
  3790     obtains
  3791       A
  3792     | B
  3793 
  3794 The subsequent classical rules even refer to the formal "thesis"
  3795 explicitly:
  3796 
  3797   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3798     obtains "~ thesis"
  3799 
  3800   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3801     obtains "thesis ==> something"
  3802 
  3803 The actual proof of an 'obtains' statement is analogous to that of the
  3804 Isar proof element 'obtain', only that there may be several cases.
  3805 Optional case names may be specified in parentheses; these will be
  3806 available both in the present proof and as annotations in the
  3807 resulting rule, for later use with the 'cases' method (cf. attribute
  3808 case_names).
  3809 
  3810 * Isar: the assumptions of a long theorem statement are available as
  3811 "assms" fact in the proof context.  This is more appropriate than the
  3812 (historical) "prems", which refers to all assumptions of the current
  3813 context, including those from the target locale, proof body etc.
  3814 
  3815 * Isar: 'print_statement' prints theorems from the current theory or
  3816 proof context in long statement form, according to the syntax of a
  3817 top-level lemma.
  3818 
  3819 * Isar: 'obtain' takes an optional case name for the local context
  3820 introduction rule (default "that").
  3821 
  3822 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3823 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3824 to occur.
  3825 
  3826 * Pure: syntax "CONST name" produces a fully internalized constant
  3827 according to the current context.  This is particularly useful for
  3828 syntax translations that should refer to internal constant
  3829 representations independently of name spaces.
  3830 
  3831 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3832 instead of "FOO ". This allows multiple binder declarations to coexist
  3833 in the same context.  INCOMPATIBILITY.
  3834 
  3835 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3836 primitive that also works in a locale context (both for constants and
  3837 fixed variables). Type declaration and internal syntactic representation
  3838 of given constants retrieved from the context. Likewise, the
  3839 'no_notation' command allows to remove given syntax annotations from the
  3840 current context.
  3841 
  3842 * Isar/locales: new derived specification elements 'axiomatization',
  3843 'definition', 'abbreviation', which support type-inference, admit
  3844 object-level specifications (equality, equivalence).  See also the
  3845 isar-ref manual.  Examples:
  3846 
  3847   axiomatization
  3848     eq  (infix "===" 50) where
  3849     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3850 
  3851   definition "f x y = x + y + 1"
  3852   definition g where "g x = f x x"
  3853 
  3854   abbreviation
  3855     neq  (infix "=!=" 50) where
  3856     "x =!= y == ~ (x === y)"
  3857 
  3858 These specifications may be also used in a locale context.  Then the
  3859 constants being introduced depend on certain fixed parameters, and the
  3860 constant name is qualified by the locale base name.  An internal
  3861 abbreviation takes care for convenient input and output, making the
  3862 parameters implicit and using the original short name.  See also
  3863 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3864 entities from a monomorphic theory.
  3865 
  3866 Presently, abbreviations are only available 'in' a target locale, but
  3867 not inherited by general import expressions.  Also note that
  3868 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3869 'translations' in common applications.  The "no_abbrevs" print mode
  3870 prevents folding of abbreviations in term output.
  3871 
  3872 Concrete syntax is attached to specified constants in internal form,
  3873 independently of name spaces.  The parse tree representation is
  3874 slightly different -- use 'notation' instead of raw 'syntax', and
  3875 'translations' with explicit "CONST" markup to accommodate this.
  3876 
  3877 * Pure/Isar: unified syntax for new-style specification mechanisms
  3878 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3879 full type inference and dummy patterns ("_").  For example:
  3880 
  3881   definition "K x _ = x"
  3882 
  3883   inductive conj for A B
  3884   where "A ==> B ==> conj A B"
  3885 
  3886 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3887 the current context.  Print mode "no_abbrevs" prevents inversion of
  3888 abbreviations on output.
  3889 
  3890 * Isar/locales: improved parameter handling: use of locales "var" and
  3891 "struct" no longer necessary; - parameter renamings are no longer
  3892 required to be injective.  For example, this allows to define
  3893 endomorphisms as locale endom = homom mult mult h.
  3894 
  3895 * Isar/locales: changed the way locales with predicates are defined.
  3896 Instead of accumulating the specification, the imported expression is
  3897 now an interpretation.  INCOMPATIBILITY: different normal form of
  3898 locale expressions.  In particular, in interpretations of locales with
  3899 predicates, goals repesenting already interpreted fragments are not
  3900 removed automatically.  Use methods `intro_locales' and
  3901 `unfold_locales'; see below.
  3902 
  3903 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3904 provide backward reasoning on locales predicates.  The methods are
  3905 aware of interpretations and discharge corresponding goals.
  3906 `intro_locales' is less aggressive then `unfold_locales' and does not
  3907 unfold predicates to assumptions.
  3908 
  3909 * Isar/locales: the order in which locale fragments are accumulated
  3910 has changed.  This enables to override declarations from fragments due
  3911 to interpretations -- for example, unwanted simp rules.
  3912 
  3913 * Isar/locales: interpretation in theories and proof contexts has been
  3914 extended.  One may now specify (and prove) equations, which are
  3915 unfolded in interpreted theorems.  This is useful for replacing
  3916 defined concepts (constants depending on locale parameters) by
  3917 concepts already existing in the target context.  Example:
  3918 
  3919   interpretation partial_order ["op <= :: [int, int] => bool"]
  3920     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3921 
  3922 Typically, the constant `partial_order.less' is created by a
  3923 definition specification element in the context of locale
  3924 partial_order.
  3925 
  3926 * Method "induct": improved internal context management to support
  3927 local fixes and defines on-the-fly. Thus explicit meta-level
  3928 connectives !!  and ==> are rarely required anymore in inductive goals
  3929 (using object-logic connectives for this purpose has been long
  3930 obsolete anyway). Common proof patterns are explained in
  3931 src/HOL/Induct/Common_Patterns.thy, see also
  3932 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3933 examples.
  3934 
  3935 * Method "induct": improved handling of simultaneous goals. Instead of
  3936 introducing object-level conjunction, the statement is now split into
  3937 several conclusions, while the corresponding symbolic cases are nested
  3938 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3939 see src/HOL/Induct/Common_Patterns.thy, for example.
  3940 
  3941 * Method "induct": mutual induction rules are now specified as a list
  3942 of rule sharing the same induction cases. HOL packages usually provide
  3943 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3944 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3945 mutual induction rules differently, i.e. like this:
  3946 
  3947   (induct rule: foo_bar.inducts)
  3948   (induct set: foo bar)
  3949   (induct pred: foo bar)
  3950   (induct type: foo bar)
  3951 
  3952 The ML function ProjectRule.projections turns old-style rules into the
  3953 new format.
  3954 
  3955 * Method "coinduct": dual of induction, see
  3956 src/HOL/Library/Coinductive_List.thy for various examples.
  3957 
  3958 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3959 considered a legacy feature.
  3960 
  3961 * Attribute "symmetric" produces result with standardized schematic
  3962 variables (index 0).  Potential INCOMPATIBILITY.
  3963 
  3964 * Simplifier: by default the simplifier trace only shows top level
  3965 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3966 default. Thus there is less danger of being flooded by the trace. The
  3967 trace indicates where parts have been suppressed.
  3968   
  3969 * Provers/classical: removed obsolete classical version of elim_format
  3970 attribute; classical elim/dest rules are now treated uniformly when
  3971 manipulating the claset.
  3972 
  3973 * Provers/classical: stricter checks to ensure that supplied intro,
  3974 dest and elim rules are well-formed; dest and elim rules must have at
  3975 least one premise.
  3976 
  3977 * Provers/classical: attributes dest/elim/intro take an optional
  3978 weight argument for the rule (just as the Pure versions).  Weights are
  3979 ignored by automated tools, but determine the search order of single
  3980 rule steps.
  3981 
  3982 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3983 where the body does not mention the bound variable.  Note that dummy
  3984 patterns implicitly depend on their context of bounds, which makes
  3985 "{_. _}" match any set comprehension as expected.  Potential
  3986 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3987 constant "_idtdummy" in the binding position.
  3988 
  3989 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3990 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3991 for example "A -> B" => "Pi A (%_. B)".
  3992 
  3993 * Pure: 'class_deps' command visualizes the subclass relation, using
  3994 the graph browser tool.
  3995 
  3996 * Pure: 'print_theory' now suppresses certain internal declarations by
  3997 default; use '!' option for full details.
  3998 
  3999 
  4000 *** HOL ***
  4001 
  4002 * Method "metis" proves goals by applying the Metis general-purpose
  4003 resolution prover (see also http://gilith.com/software/metis/).
  4004 Examples are in the directory MetisExamples.  WARNING: the
  4005 Isabelle/HOL-Metis integration does not yet work properly with
  4006 multi-threading.
  4007   
  4008 * Command 'sledgehammer' invokes external automatic theorem provers as
  4009 background processes.  It generates calls to the "metis" method if
  4010 successful. These can be pasted into the proof.  Users do not have to
  4011 wait for the automatic provers to return.  WARNING: does not really
  4012 work with multi-threading.
  4013 
  4014 * New "auto_quickcheck" feature tests outermost goal statements for
  4015 potential counter-examples.  Controlled by ML references
  4016 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4017 5000 milliseconds).  Fails silently if statements is outside of
  4018 executable fragment, or any other codgenerator problem occurs.
  4019 
  4020 * New constant "undefined" with axiom "undefined x = undefined".
  4021 
  4022 * Added class "HOL.eq", allowing for code generation with polymorphic
  4023 equality.
  4024 
  4025 * Some renaming of class constants due to canonical name prefixing in
  4026 the new 'class' package:
  4027 
  4028     HOL.abs ~> HOL.abs_class.abs
  4029     HOL.divide ~> HOL.divide_class.divide
  4030     0 ~> HOL.zero_class.zero
  4031     1 ~> HOL.one_class.one
  4032     op + ~> HOL.plus_class.plus
  4033     op - ~> HOL.minus_class.minus
  4034     uminus ~> HOL.minus_class.uminus
  4035     op * ~> HOL.times_class.times
  4036     op < ~> HOL.ord_class.less
  4037     op <= > HOL.ord_class.less_eq
  4038     Nat.power ~> Power.power_class.power
  4039     Nat.size ~> Nat.size_class.size
  4040     Numeral.number_of ~> Numeral.number_class.number_of
  4041     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4042     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4043     Orderings.min ~> Orderings.ord_class.min
  4044     Orderings.max ~> Orderings.ord_class.max
  4045     Divides.op div ~> Divides.div_class.div
  4046     Divides.op mod ~> Divides.div_class.mod
  4047     Divides.op dvd ~> Divides.div_class.dvd
  4048 
  4049 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4050 
  4051 a) User-defined constants using any of the names "plus", "minus",
  4052 "times", "less" or "less_eq". The standard syntax translations for
  4053 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4054 names.
  4055 
  4056 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4057 INCOMPATIBILITY: use more specific names.
  4058 
  4059 c) Permutative equations (e.g. "a + b = b + a")
  4060 Since the change of names also changes the order of terms, permutative
  4061 rewrite rules may get applied in a different order. Experience shows
  4062 that this is rarely the case (only two adaptions in the whole Isabelle
  4063 distribution).  INCOMPATIBILITY: rewrite proofs
  4064 
  4065 d) ML code directly refering to constant names
  4066 This in general only affects hand-written proof tactics, simprocs and
  4067 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4068 Consider using @{const_name} antiquotation.
  4069 
  4070 * New class "default" with associated constant "default".
  4071 
  4072 * Function "sgn" is now overloaded and available on int, real, complex
  4073 (and other numeric types), using class "sgn".  Two possible defs of
  4074 sgn are given as equational assumptions in the classes sgn_if and
  4075 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4076 INCOMPATIBILITY.
  4077 
  4078 * Locale "partial_order" now unified with class "order" (cf. theory
  4079 Orderings), added parameter "less".  INCOMPATIBILITY.
  4080 
  4081 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4082 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4083 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4084 
  4085 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4086 changed order of proof goals in instance proofs.
  4087 
  4088 * The transitivity reasoner for partial and linear orders is set up
  4089 for classes "order" and "linorder".  Instances of the reasoner are available
  4090 in all contexts importing or interpreting the corresponding locales.
  4091 Method "order" invokes the reasoner separately; the reasoner
  4092 is also integrated with the Simplifier as a solver.  Diagnostic
  4093 command 'print_orders' shows the available instances of the reasoner
  4094 in the current context.
  4095 
  4096 * Localized monotonicity predicate in theory "Orderings"; integrated
  4097 lemmas max_of_mono and min_of_mono with this predicate.
  4098 INCOMPATIBILITY.
  4099 
  4100 * Formulation of theorem "dense" changed slightly due to integration
  4101 with new class dense_linear_order.
  4102 
  4103 * Uniform lattice theory development in HOL.
  4104 
  4105     constants "meet" and "join" now named "inf" and "sup"
  4106     constant "Meet" now named "Inf"
  4107 
  4108     classes "meet_semilorder" and "join_semilorder" now named
  4109       "lower_semilattice" and "upper_semilattice"
  4110     class "lorder" now named "lattice"
  4111     class "comp_lat" now named "complete_lattice"
  4112 
  4113     Instantiation of lattice classes allows explicit definitions
  4114     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4115 
  4116   INCOMPATIBILITY.  Theorem renames:
  4117 
  4118     meet_left_le            ~> inf_le1
  4119     meet_right_le           ~> inf_le2
  4120     join_left_le            ~> sup_ge1
  4121     join_right_le           ~> sup_ge2
  4122     meet_join_le            ~> inf_sup_ord
  4123     le_meetI                ~> le_infI
  4124     join_leI                ~> le_supI
  4125     le_meet                 ~> le_inf_iff
  4126     le_join                 ~> ge_sup_conv
  4127     meet_idempotent         ~> inf_idem
  4128     join_idempotent         ~> sup_idem
  4129     meet_comm               ~> inf_commute
  4130     join_comm               ~> sup_commute
  4131     meet_leI1               ~> le_infI1
  4132     meet_leI2               ~> le_infI2
  4133     le_joinI1               ~> le_supI1
  4134     le_joinI2               ~> le_supI2
  4135     meet_assoc              ~> inf_assoc
  4136     join_assoc              ~> sup_assoc
  4137     meet_left_comm          ~> inf_left_commute
  4138     meet_left_idempotent    ~> inf_left_idem
  4139     join_left_comm          ~> sup_left_commute
  4140     join_left_idempotent    ~> sup_left_idem
  4141     meet_aci                ~> inf_aci
  4142     join_aci                ~> sup_aci
  4143     le_def_meet             ~> le_iff_inf
  4144     le_def_join             ~> le_iff_sup
  4145     join_absorp2            ~> sup_absorb2
  4146     join_absorp1            ~> sup_absorb1
  4147     meet_absorp1            ~> inf_absorb1
  4148     meet_absorp2            ~> inf_absorb2
  4149     meet_join_absorp        ~> inf_sup_absorb
  4150     join_meet_absorp        ~> sup_inf_absorb
  4151     distrib_join_le         ~> distrib_sup_le
  4152     distrib_meet_le         ~> distrib_inf_le
  4153 
  4154     add_meet_distrib_left   ~> add_inf_distrib_left
  4155     add_join_distrib_left   ~> add_sup_distrib_left
  4156     is_join_neg_meet        ~> is_join_neg_inf
  4157     is_meet_neg_join        ~> is_meet_neg_sup
  4158     add_meet_distrib_right  ~> add_inf_distrib_right
  4159     add_join_distrib_right  ~> add_sup_distrib_right
  4160     add_meet_join_distribs  ~> add_sup_inf_distribs
  4161     join_eq_neg_meet        ~> sup_eq_neg_inf
  4162     meet_eq_neg_join        ~> inf_eq_neg_sup
  4163     add_eq_meet_join        ~> add_eq_inf_sup
  4164     meet_0_imp_0            ~> inf_0_imp_0
  4165     join_0_imp_0            ~> sup_0_imp_0
  4166     meet_0_eq_0             ~> inf_0_eq_0
  4167     join_0_eq_0             ~> sup_0_eq_0
  4168     neg_meet_eq_join        ~> neg_inf_eq_sup
  4169     neg_join_eq_meet        ~> neg_sup_eq_inf
  4170     join_eq_if              ~> sup_eq_if
  4171 
  4172     mono_meet               ~> mono_inf
  4173     mono_join               ~> mono_sup
  4174     meet_bool_eq            ~> inf_bool_eq
  4175     join_bool_eq            ~> sup_bool_eq
  4176     meet_fun_eq             ~> inf_fun_eq
  4177     join_fun_eq             ~> sup_fun_eq
  4178     meet_set_eq             ~> inf_set_eq
  4179     join_set_eq             ~> sup_set_eq
  4180     meet1_iff               ~> inf1_iff
  4181     meet2_iff               ~> inf2_iff
  4182     meet1I                  ~> inf1I
  4183     meet2I                  ~> inf2I
  4184     meet1D1                 ~> inf1D1
  4185     meet2D1                 ~> inf2D1
  4186     meet1D2                 ~> inf1D2
  4187     meet2D2                 ~> inf2D2
  4188     meet1E                  ~> inf1E
  4189     meet2E                  ~> inf2E
  4190     join1_iff               ~> sup1_iff
  4191     join2_iff               ~> sup2_iff
  4192     join1I1                 ~> sup1I1
  4193     join2I1                 ~> sup2I1
  4194     join1I1                 ~> sup1I1
  4195     join2I2                 ~> sup1I2
  4196     join1CI                 ~> sup1CI
  4197     join2CI                 ~> sup2CI
  4198     join1E                  ~> sup1E
  4199     join2E                  ~> sup2E
  4200 
  4201     is_meet_Meet            ~> is_meet_Inf
  4202     Meet_bool_def           ~> Inf_bool_def
  4203     Meet_fun_def            ~> Inf_fun_def
  4204     Meet_greatest           ~> Inf_greatest
  4205     Meet_lower              ~> Inf_lower
  4206     Meet_set_def            ~> Inf_set_def
  4207 
  4208     Sup_def                 ~> Sup_Inf
  4209     Sup_bool_eq             ~> Sup_bool_def
  4210     Sup_fun_eq              ~> Sup_fun_def
  4211     Sup_set_eq              ~> Sup_set_def
  4212 
  4213     listsp_meetI            ~> listsp_infI
  4214     listsp_meet_eq          ~> listsp_inf_eq
  4215 
  4216     meet_min                ~> inf_min
  4217     join_max                ~> sup_max
  4218 
  4219 * Added syntactic class "size"; overloaded constant "size" now has
  4220 type "'a::size ==> bool"
  4221 
  4222 * Internal reorganisation of `size' of datatypes: size theorems
  4223 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4224 simplification rules by default!); theorems "prod.size" now named
  4225 "*.size".
  4226 
  4227 * Class "div" now inherits from class "times" rather than "type".
  4228 INCOMPATIBILITY.
  4229 
  4230 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4231 Linorder etc.  have disappeared; operations defined in terms of
  4232 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4233 
  4234 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4235 
  4236 * HOL-Word: New extensive library and type for generic, fixed size
  4237 machine words, with arithemtic, bit-wise, shifting and rotating
  4238 operations, reflection into int, nat, and bool lists, automation for
  4239 linear arithmetic (by automatic reflection into nat or int), including
  4240 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4241 arithmetic type classes, supporting automatic simplification of
  4242 numerals on all operations.
  4243 
  4244 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4245 
  4246 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4247 
  4248 * Code generator library theories:
  4249   - Code_Integer represents HOL integers by big integer literals in target
  4250     languages.
  4251   - Code_Char represents HOL characters by character literals in target
  4252     languages.
  4253   - Code_Char_chr like Code_Char, but also offers treatment of character
  4254     codes; includes Code_Integer.
  4255   - Executable_Set allows to generate code for finite sets using lists.
  4256   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4257     denominator).
  4258   - Executable_Real implements a subset of real numbers, namly those
  4259     representable by rational numbers.
  4260   - Efficient_Nat implements natural numbers by integers, which in general will
  4261     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4262     includes Code_Integer.
  4263   - Code_Index provides an additional datatype index which is mapped to
  4264     target-language built-in integers.
  4265   - Code_Message provides an additional datatype message_string which is isomorphic to
  4266     strings; messages are mapped to target-language strings.
  4267 
  4268 * New package for inductive predicates
  4269 
  4270   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4271 
  4272     inductive
  4273       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4274       for z_1 :: U_1 and ... and z_n :: U_m
  4275     where
  4276       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4277     | ...
  4278 
  4279   with full support for type-inference, rather than
  4280 
  4281     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4282 
  4283     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4284     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4285 
  4286     inductive "s z_1 ... z_m"
  4287     intros
  4288       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4289       ...
  4290 
  4291   For backward compatibility, there is a wrapper allowing inductive
  4292   sets to be defined with the new package via
  4293 
  4294     inductive_set
  4295       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4296       for z_1 :: U_1 and ... and z_n :: U_m
  4297     where
  4298       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4299     | ...
  4300 
  4301   or
  4302 
  4303     inductive_set
  4304       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4305       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4306       for z_1 :: U_1 and ... and z_n :: U_m
  4307     where
  4308       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4309     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4310     | ...
  4311 
  4312   if the additional syntax "p ..." is required.
  4313 
  4314   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4315   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4316 
  4317   INCOMPATIBILITIES:
  4318 
  4319   - Since declaration and definition of inductive sets or predicates
  4320     is no longer separated, abbreviations involving the newly
  4321     introduced sets or predicates must be specified together with the
  4322     introduction rules after the 'where' keyword (see above), rather
  4323     than before the actual inductive definition.
  4324 
  4325   - The variables in induction and elimination rules are now
  4326     quantified in the order of their occurrence in the introduction
  4327     rules, rather than in alphabetical order. Since this may break
  4328     some proofs, these proofs either have to be repaired, e.g. by
  4329     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4330     statements of the form
  4331 
  4332       case (rule_i a_i_1 ... a_i_{k_i})
  4333 
  4334     or the old order of quantification has to be restored by explicitly adding
  4335     meta-level quantifiers in the introduction rules, i.e.
  4336 
  4337       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4338 
  4339   - The format of the elimination rules is now
  4340 
  4341       p z_1 ... z_m x_1 ... x_n ==>
  4342         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4343         ==> ... ==> P
  4344 
  4345     for predicates and
  4346 
  4347       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4348         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4349         ==> ... ==> P
  4350 
  4351     for sets rather than
  4352 
  4353       x : s z_1 ... z_m ==>
  4354         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4355         ==> ... ==> P
  4356 
  4357     This may require terms in goals to be expanded to n-tuples
  4358     (e.g. using case_tac or simplification with the split_paired_all
  4359     rule) before the above elimination rule is applicable.
  4360 
  4361   - The elimination or case analysis rules for (mutually) inductive
  4362     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4363     list of rules "p_1_..._p_k.elims" is no longer available.
  4364 
  4365 * New package "function"/"fun" for general recursive functions,
  4366 supporting mutual and nested recursion, definitions in local contexts,
  4367 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4368 for small examples, and the separate tutorial on the function
  4369 package. The old recdef "package" is still available as before, but
  4370 users are encouraged to use the new package.
  4371 
  4372 * Method "lexicographic_order" automatically synthesizes termination
  4373 relations as lexicographic combinations of size measures. 
  4374 
  4375 * Case-expressions allow arbitrary constructor-patterns (including
  4376 "_") and take their order into account, like in functional
  4377 programming.  Internally, this is translated into nested
  4378 case-expressions; missing cases are added and mapped to the predefined
  4379 constant "undefined". In complicated cases printing may no longer show
  4380 the original input but the internal form. Lambda-abstractions allow
  4381 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4382 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4383 variable.
  4384 
  4385 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4386 is an abbreviation for "of_nat :: nat => int". The simplification
  4387 rules for "of_nat" have been changed to work like "int" did
  4388 previously.  Potential INCOMPATIBILITY:
  4389   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4390   - of_nat_diff and of_nat_mult are no longer default simp rules
  4391 
  4392 * Method "algebra" solves polynomial equations over (semi)rings using
  4393 Groebner bases. The (semi)ring structure is defined by locales and the
  4394 tool setup depends on that generic context. Installing the method for
  4395 a specific type involves instantiating the locale and possibly adding
  4396 declarations for computation on the coefficients.  The method is
  4397 already instantiated for natural numbers and for the axiomatic class
  4398 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4399 CALCULEMUS 2007 for the general principles underlying this
  4400 architecture of context-aware proof-tools.
  4401 
  4402 * Method "ferrack" implements quantifier elimination over
  4403 special-purpose dense linear orders using locales (analogous to
  4404 "algebra"). The method is already installed for class
  4405 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4406 rat, etc.
  4407 
  4408 * Former constant "List.op @" now named "List.append".  Use ML
  4409 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4410 circumvent possible incompatibilities when working on ML level.
  4411 
  4412 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4413 
  4414 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4415 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4416 
  4417 * New syntax for Haskell-like list comprehension (input only), eg.
  4418 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4419 
  4420 * The special syntax for function "filter" has changed from [x :
  4421 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4422 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4423 
  4424 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4425 defined on nat only, as an abbreviation for [a..<Suc b]
  4426 INCOMPATIBILITY.
  4427 
  4428 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4429 
  4430 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4431 
  4432 * New lemma collection field_simps (an extension of ring_simps) for
  4433 manipulating (in)equations involving division. Multiplies with all
  4434 denominators that can be proved to be non-zero (in equations) or
  4435 positive/negative (in inequations).
  4436 
  4437 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4438 have been improved and renamed to ring_simps, group_simps and
  4439 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4440 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4441 
  4442 * Theory Library/Commutative_Ring: switched from recdef to function
  4443 package; constants add, mul, pow now curried.  Infix syntax for
  4444 algebraic operations.
  4445 
  4446 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4447 INCOMPATIBILITY.
  4448 
  4449 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4450 INCOMPATIBILITY.
  4451 
  4452 * HOL/records: generalised field-update to take a function on the
  4453 field rather than the new value: r(|A := x|) is translated to A_update
  4454 (K x) r The K-combinator that is internally used is called K_record.
  4455 INCOMPATIBILITY: Usage of the plain update functions has to be
  4456 adapted.
  4457  
  4458 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4459 * x = 0, which are required for a semiring.  Richer structures do not
  4460 inherit from semiring_0 anymore, because this property is a theorem
  4461 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4462 there is more to prove, but this is mostly trivial.
  4463 
  4464 * Class "recpower" is generalized to arbitrary monoids, not just
  4465 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4466 commutativity or semiring properties additionally.
  4467 
  4468 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4469 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4470 better use 'abbreviation'.
  4471 
  4472 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4473 
  4474 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4475 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4476 significant changes for setting up numeral syntax for types:
  4477   - New constants Numeral.pred and Numeral.succ instead
  4478       of former Numeral.bin_pred and Numeral.bin_succ.
  4479   - Use integer operations instead of bin_add, bin_mult and so on.
  4480   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4481   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4482 
  4483 See src/HOL/Integ/IntArith.thy for an example setup.
  4484 
  4485 * Command 'normal_form' computes the normal form of a term that may
  4486 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4487 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4488 heavy-duty computations because the functions are compiled to ML
  4489 first.  Correspondingly, a method "normalization" is provided.  See
  4490 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4491 
  4492 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4493 25 like -->); output depends on the "iff" print_mode, the default is
  4494 "A = B" (with priority 50).
  4495 
  4496 * Relations less (<) and less_eq (<=) are also available on type bool.
  4497 Modified syntax to disallow nesting without explicit parentheses,
  4498 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4499 INCOMPATIBILITY.
  4500 
  4501 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4502 
  4503 * Relation composition operator "op O" now has precedence 75 and binds
  4504 stronger than union and intersection. INCOMPATIBILITY.
  4505 
  4506 * The old set interval syntax "{m..n(}" (and relatives) has been
  4507 removed.  Use "{m..<n}" (and relatives) instead.
  4508 
  4509 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4510 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4511 ``declare [[simproc del: neq]]''.
  4512 
  4513 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4514 True/False.
  4515 
  4516 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4517 
  4518 * Theorem setsum_mult renamed to setsum_right_distrib.
  4519 
  4520 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4521 ``rule'' method.
  4522 
  4523 * Reimplemented methods "sat" and "satx", with several improvements:
  4524 goals no longer need to be stated as "<prems> ==> False", equivalences
  4525 (i.e. "=" on type bool) are handled, variable names of the form
  4526 "lit_<n>" are no longer reserved, significant speedup.
  4527 
  4528 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4529 zChaff is still supported as well.
  4530 
  4531 * 'inductive' and 'datatype': provide projections of mutual rules,
  4532 bundled as foo_bar.inducts;
  4533 
  4534 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4535 Library.
  4536 
  4537 * Library: moved theory Accessible_Part to main HOL.
  4538 
  4539 * Library: added theory Coinductive_List of potentially infinite lists
  4540 as greatest fixed-point.
  4541 
  4542 * Library: added theory AssocList which implements (finite) maps as
  4543 association lists.
  4544 
  4545 * Method "evaluation" solves goals (i.e. a boolean expression)
  4546 efficiently by compiling it to ML.  The goal is "proved" (via an
  4547 oracle) if it evaluates to True.
  4548 
  4549 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4550 also when invoked by the simplifier.  This results in the Simplifier
  4551 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4552 Configuration option fast_arith_split_limit=0 recovers the old
  4553 behavior.
  4554 
  4555 * Support for hex (0x20) and binary (0b1001) numerals.
  4556 
  4557 * New method: reify eqs (t), where eqs are equations for an
  4558 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4559 parameter, computes a term s::'b and a list xs::'a list and proves the
  4560 theorem I xs s = t. This is also known as reification or quoting. The
  4561 resulting theorem is applied to the subgoal to substitute t with I xs
  4562 s.  If t is omitted, the subgoal itself is reified.
  4563 
  4564 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4565 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4566 where f is supposed to be a computable function (in the sense of code
  4567 generattion). The method uses reify to compute s and xs as above then
  4568 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4569 r and finally gets the theorem t = r, which is again applied to the
  4570 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4571 
  4572 * Reflection: Automatic reification now handels binding, an example is
  4573 available in src/HOL/ex/ReflectionEx.thy
  4574 
  4575 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4576 command 'statespace' that is similar to 'record', but introduces an
  4577 abstract specification based on the locale infrastructure instead of
  4578 HOL types.  This leads to extra flexibility in composing state spaces,
  4579 in particular multiple inheritance and renaming of components.
  4580 
  4581 
  4582 *** HOL-Complex ***
  4583 
  4584 * Hyperreal: Functions root and sqrt are now defined on negative real
  4585 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4586 Nonnegativity side conditions have been removed from many lemmas, so
  4587 that more subgoals may now be solved by simplification; potential
  4588 INCOMPATIBILITY.
  4589 
  4590 * Real: new type classes formalize real normed vector spaces and
  4591 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4592 and norm :: 'a => real.
  4593 
  4594 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4595 reals into other types. The overloaded constant Reals :: 'a set is now
  4596 defined as range of_real; potential INCOMPATIBILITY.
  4597 
  4598 * Real: proper support for ML code generation, including 'quickcheck'.
  4599 Reals are implemented as arbitrary precision rationals.
  4600 
  4601 * Hyperreal: Several constants that previously worked only for the
  4602 reals have been generalized, so they now work over arbitrary vector
  4603 spaces. Type annotations may need to be added in some cases; potential
  4604 INCOMPATIBILITY.
  4605 
  4606   Infinitesimal  :: ('a::real_normed_vector) star set
  4607   HFinite        :: ('a::real_normed_vector) star set
  4608   HInfinite      :: ('a::real_normed_vector) star set
  4609   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4610   monad          :: ('a::real_normed_vector) star => 'a star set
  4611   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4612   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4613   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4614   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4615   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4616   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4617   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4618   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4619   sgn            :: 'a::real_normed_vector => 'a
  4620   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4621 
  4622 * Complex: Some complex-specific constants are now abbreviations for
  4623 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4624 hnorm.  Other constants have been entirely removed in favor of the
  4625 polymorphic versions (INCOMPATIBILITY):
  4626 
  4627   approx        <-- capprox
  4628   HFinite       <-- CFinite
  4629   HInfinite     <-- CInfinite
  4630   Infinitesimal <-- CInfinitesimal
  4631   monad         <-- cmonad
  4632   galaxy        <-- cgalaxy
  4633   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4634   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4635   (ns)deriv     <-- (ns)cderiv
  4636 
  4637 
  4638 *** HOL-Algebra ***
  4639 
  4640 * Formalisation of ideals and the quotient construction over rings.
  4641 
  4642 * Order and lattice theory no longer based on records.
  4643 INCOMPATIBILITY.
  4644 
  4645 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4646 greatest_closed.  INCOMPATIBILITY.
  4647 
  4648 * Method algebra is now set up via an attribute.  For examples see
  4649 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4650 of algebraic structures.
  4651 
  4652 * Renamed theory CRing to Ring.
  4653 
  4654 
  4655 *** HOL-Nominal ***
  4656 
  4657 * Substantial, yet incomplete support for nominal datatypes (binding
  4658 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4659 src/HOL/Nominal/Examples.  Prospective users should consult
  4660 http://isabelle.in.tum.de/nominal/
  4661 
  4662 
  4663 *** ML ***
  4664 
  4665 * ML basics: just one true type int, which coincides with IntInf.int
  4666 (even on SML/NJ).
  4667 
  4668 * ML within Isar: antiquotations allow to embed statically-checked
  4669 formal entities in the source, referring to the context available at
  4670 compile-time.  For example:
  4671 
  4672 ML {* @{sort "{zero,one}"} *}
  4673 ML {* @{typ "'a => 'b"} *}
  4674 ML {* @{term "%x. x"} *}
  4675 ML {* @{prop "x == y"} *}
  4676 ML {* @{ctyp "'a => 'b"} *}
  4677 ML {* @{cterm "%x. x"} *}
  4678 ML {* @{cprop "x == y"} *}
  4679 ML {* @{thm asm_rl} *}
  4680 ML {* @{thms asm_rl} *}
  4681 ML {* @{type_name c} *}
  4682 ML {* @{type_syntax c} *}
  4683 ML {* @{const_name c} *}
  4684 ML {* @{const_syntax c} *}
  4685 ML {* @{context} *}
  4686 ML {* @{theory} *}
  4687 ML {* @{theory Pure} *}
  4688 ML {* @{theory_ref} *}
  4689 ML {* @{theory_ref Pure} *}
  4690 ML {* @{simpset} *}
  4691 ML {* @{claset} *}
  4692 ML {* @{clasimpset} *}
  4693 
  4694 The same works for sources being ``used'' within an Isar context.
  4695 
  4696 * ML in Isar: improved error reporting; extra verbosity with
  4697 ML_Context.trace enabled.
  4698 
  4699 * Pure/General/table.ML: the join operations now works via exceptions
  4700 DUP/SAME instead of type option. This is simpler in simple cases, and
  4701 admits slightly more efficient complex applications.
  4702 
  4703 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4704 use Context.generic instead of just theory.
  4705 
  4706 * Pure: datatype Context.generic joins theory/Proof.context and
  4707 provides some facilities for code that works in either kind of
  4708 context, notably GenericDataFun for uniform theory and proof data.
  4709 
  4710 * Pure: simplified internal attribute type, which is now always
  4711 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4712 local (Proof.context) attributes have been discontinued, while
  4713 minimizing code duplication. Thm.rule_attribute and
  4714 Thm.declaration_attribute build canonical attributes; see also structure
  4715 Context for further operations on Context.generic, notably
  4716 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4717 declarations and definitions.
  4718 
  4719 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4720 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4721 init only required for impure data. INCOMPATIBILITY: empty really need
  4722 to be empty (no dependencies on theory content!)
  4723 
  4724 * Pure/kernel: consts certification ignores sort constraints given in
  4725 signature declarations. (This information is not relevant to the
  4726 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4727 potential INCOMPATIBILITY.
  4728 
  4729 * Pure: axiomatic type classes are now purely definitional, with
  4730 explicit proofs of class axioms and super class relations performed
  4731 internally. See Pure/axclass.ML for the main internal interfaces --
  4732 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4733 AxClass.axiomatize_class/classrel/arity supersede
  4734 Sign.add_classes/classrel/arities.
  4735 
  4736 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4737 global/local versions on theory vs. Proof.context have been
  4738 discontinued; Attrib.syntax and Method.syntax have been adapted
  4739 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4740 attributes, methods, etc.
  4741 
  4742 * Pure: several functions of signature "... -> theory -> theory * ..."
  4743 have been reoriented to "... -> theory -> ... * theory" in order to
  4744 allow natural usage in combination with the ||>, ||>>, |-> and
  4745 fold_map combinators.
  4746 
  4747 * Pure: official theorem names (closed derivations) and additional
  4748 comments (tags) are now strictly separate.  Name hints -- which are
  4749 maintained as tags -- may be attached any time without affecting the
  4750 derivation.
  4751 
  4752 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4753 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4754 achieve the old behaviour.
  4755 
  4756 * Pure: the "Goal" constant is now called "prop", supporting a
  4757 slightly more general idea of ``protecting'' meta-level rule
  4758 statements.
  4759 
  4760 * Pure: Logic.(un)varify only works in a global context, which is now
  4761 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4762 Logic.legacy_(un)varify as temporary workaround.
  4763 
  4764 * Pure: structure Name provides scalable operations for generating
  4765 internal variable names, notably Name.variants etc.  This replaces
  4766 some popular functions from term.ML:
  4767 
  4768   Term.variant		->  Name.variant
  4769   Term.variantlist	->  Name.variant_list
  4770   Term.invent_names	->  Name.invent_list
  4771 
  4772 Note that low-level renaming rarely occurs in new code -- operations
  4773 from structure Variable are used instead (see below).
  4774 
  4775 * Pure: structure Variable provides fundamental operations for proper
  4776 treatment of fixed/schematic variables in a context.  For example,
  4777 Variable.import introduces fixes for schematics of given facts and
  4778 Variable.export reverses the effect (up to renaming) -- this replaces
  4779 various freeze_thaw operations.
  4780 
  4781 * Pure: structure Goal provides simple interfaces for
  4782 init/conclude/finish and tactical prove operations (replacing former
  4783 Tactic.prove).  Goal.prove is the canonical way to prove results
  4784 within a given context; Goal.prove_global is a degraded version for
  4785 theory level goals, including a global Drule.standard.  Note that
  4786 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4787 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4788 in a locale context).
  4789 
  4790 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4791 and type checking (Syntax.check_term etc.), with common combinations
  4792 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4793 which are considered legacy and await removal.
  4794 
  4795 * Pure/Syntax: generic interfaces for type unchecking
  4796 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4797 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4798 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4799 available for convenience, but refer to the very same operations using
  4800 a mere theory instead of a full context.
  4801 
  4802 * Isar: simplified treatment of user-level errors, using exception
  4803 ERROR of string uniformly.  Function error now merely raises ERROR,
  4804 without any side effect on output channels.  The Isar toplevel takes
  4805 care of proper display of ERROR exceptions.  ML code may use plain
  4806 handle/can/try; cat_error may be used to concatenate errors like this:
  4807 
  4808   ... handle ERROR msg => cat_error msg "..."
  4809 
  4810 Toplevel ML code (run directly or through the Isar toplevel) may be
  4811 embedded into the Isar toplevel with exception display/debug like
  4812 this:
  4813 
  4814   Isar.toplevel (fn () => ...)
  4815 
  4816 INCOMPATIBILITY, removed special transform_error facilities, removed
  4817 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4818 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4819 -- use plain ERROR instead.
  4820 
  4821 * Isar: theory setup now has type (theory -> theory), instead of a
  4822 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4823 
  4824 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4825 ProofContext.debug/verbose flags.
  4826 
  4827 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4828 theory before entering a proof state.  Transactions now always see a
  4829 quasi-functional intermediate checkpoint, both in interactive and
  4830 batch mode.
  4831 
  4832 * Isar: simplified interfaces for outer syntax.  Renamed
  4833 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4834 OuterSyntax.add_parsers -- this functionality is now included in
  4835 OuterSyntax.command etc.  INCOMPATIBILITY.
  4836 
  4837 * Simplifier: the simpset of a running simplification process now
  4838 contains a proof context (cf. Simplifier.the_context), which is the
  4839 very context that the initial simpset has been retrieved from (by
  4840 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4841 (solver, looper etc.) may depend on arbitrary proof data.
  4842 
  4843 * Simplifier.inherit_context inherits the proof context (plus the
  4844 local bounds) of the current simplification process; any simproc
  4845 etc. that calls the Simplifier recursively should do this!  Removed
  4846 former Simplifier.inherit_bounds, which is already included here --
  4847 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4848 specify an explicit context using Simplifier.context/theory_context.
  4849 
  4850 * Simplifier/Classical Reasoner: more abstract interfaces
  4851 change_simpset/claset for modifying the simpset/claset reference of a
  4852 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4853 INCOMPATIBILITY.
  4854 
  4855 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4856 "Trueprop" etc.
  4857 
  4858 
  4859 *** System ***
  4860 
  4861 * settings: the default heap location within ISABELLE_HOME_USER now
  4862 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4863 Isabelle installations.
  4864 
  4865 * isabelle-process: option -S (secure mode) disables some critical
  4866 operations, notably runtime compilation and evaluation of ML source
  4867 code.
  4868 
  4869 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4870 
  4871 * Support for parallel execution, using native multicore support of
  4872 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4873 independent theories, according to the given theory header
  4874 specifications. The maximum number of worker threads is specified via
  4875 usedir option -M or the "max-threads" setting in Proof General. A
  4876 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4877 to 6 on a 8-core machine.  User-code needs to observe certain
  4878 guidelines for thread-safe programming, see appendix A in the Isar
  4879 Implementation manual.
  4880 
  4881 
  4882 
  4883 New in Isabelle2005 (October 2005)
  4884 ----------------------------------
  4885 
  4886 *** General ***
  4887 
  4888 * Theory headers: the new header syntax for Isar theories is
  4889 
  4890   theory <name>
  4891   imports <theory1> ... <theoryN>
  4892   uses <file1> ... <fileM>
  4893   begin
  4894 
  4895 where the 'uses' part is optional.  The previous syntax
  4896 
  4897   theory <name> = <theory1> + ... + <theoryN>:
  4898 
  4899 will disappear in the next release.  Use isatool fixheaders to convert
  4900 existing theory files.  Note that there is no change in ancient
  4901 non-Isar theories now, but these will disappear soon.
  4902 
  4903 * Theory loader: parent theories can now also be referred to via
  4904 relative and absolute paths.
  4905 
  4906 * Command 'find_theorems' searches for a list of criteria instead of a
  4907 list of constants. Known criteria are: intro, elim, dest, name:string,
  4908 simp:term, and any term. Criteria can be preceded by '-' to select
  4909 theorems that do not match. Intro, elim, dest select theorems that
  4910 match the current goal, name:s selects theorems whose fully qualified
  4911 name contain s, and simp:term selects all simplification rules whose
  4912 lhs match term.  Any other term is interpreted as pattern and selects
  4913 all theorems matching the pattern. Available in ProofGeneral under
  4914 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4915 
  4916   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4917 
  4918 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4919 matching the current goal as introduction rule and not having "HOL."
  4920 in their name (i.e. not being defined in theory HOL).
  4921 
  4922 * Command 'thms_containing' has been discontinued in favour of
  4923 'find_theorems'; INCOMPATIBILITY.
  4924 
  4925 * Communication with Proof General is now 8bit clean, which means that
  4926 Unicode text in UTF-8 encoding may be used within theory texts (both
  4927 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4928 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4929 
  4930   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4931   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4932 
  4933 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4934 Classical Reasoner.  Typical big applications run around 2 times
  4935 faster.
  4936 
  4937 
  4938 *** Document preparation ***
  4939 
  4940 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4941 of raw sources.  Only those symbols that do not require additional
  4942 LaTeX packages (depending on comments in isabellesym.sty) are
  4943 displayed properly, everything else is left verbatim.  isatool display
  4944 and isatool print are used as front ends (these are subject to the
  4945 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4946 
  4947 * Command tags control specific markup of certain regions of text,
  4948 notably folding and hiding.  Predefined tags include "theory" (for
  4949 theory begin and end), "proof" for proof commands, and "ML" for
  4950 commands involving ML code; the additional tags "visible" and
  4951 "invisible" are unused by default.  Users may give explicit tag
  4952 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4953 interpretation of tags is determined by the LaTeX job during document
  4954 preparation: see option -V of isatool usedir, or options -n and -t of
  4955 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4956 \isadroptag.
  4957 
  4958 Several document versions may be produced at the same time via isatool
  4959 usedir (the generated index.html will link all of them).  Typical
  4960 specifications include ''-V document=theory,proof,ML'' to present
  4961 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4962 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4963 these parts without any formal replacement text.  The Isabelle site
  4964 default settings produce ''document'' and ''outline'' versions as
  4965 specified above.
  4966 
  4967 * Several new antiquotations:
  4968 
  4969   @{term_type term} prints a term with its type annotated;
  4970 
  4971   @{typeof term} prints the type of a term;
  4972 
  4973   @{const const} is the same as @{term const}, but checks that the
  4974   argument is a known logical constant;
  4975 
  4976   @{term_style style term} and @{thm_style style thm} print a term or
  4977   theorem applying a "style" to it
  4978 
  4979   @{ML text}
  4980 
  4981 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4982 definitions, equations, inequations etc., 'concl' printing only the
  4983 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4984 to print the specified premise.  TermStyle.add_style provides an ML
  4985 interface for introducing further styles.  See also the "LaTeX Sugar"
  4986 document practical applications.  The ML antiquotation prints
  4987 type-checked ML expressions verbatim.
  4988 
  4989 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4990 and 'text' support optional locale specification '(in loc)', which
  4991 specifies the default context for interpreting antiquotations.  For
  4992 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4993 
  4994 * Option 'locale=NAME' of antiquotations specifies an alternative
  4995 context interpreting the subsequent argument.  For example: @{thm
  4996 [locale=lattice] inf_assoc}.
  4997 
  4998 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4999 a proof context.
  5000 
  5001 * Proper output of antiquotations for theory commands involving a
  5002 proof context (such as 'locale' or 'theorem (in loc) ...').
  5003 
  5004 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5005 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5006 
  5007 * isatool usedir: new option -C (default true) controls whether option
  5008 -D should include a copy of the original document directory; -C false
  5009 prevents unwanted effects such as copying of administrative CVS data.
  5010 
  5011 
  5012 *** Pure ***
  5013 
  5014 * Considerably improved version of 'constdefs' command.  Now performs
  5015 automatic type-inference of declared constants; additional support for
  5016 local structure declarations (cf. locales and HOL records), see also
  5017 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5018 sequential dependencies of definitions within a single 'constdefs'
  5019 section; moreover, the declared name needs to be an identifier.  If
  5020 all fails, consider to fall back on 'consts' and 'defs' separately.
  5021 
  5022 * Improved indexed syntax and implicit structures.  First of all,
  5023 indexed syntax provides a notational device for subscripted
  5024 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5025 expressions.  Secondly, in a local context with structure
  5026 declarations, number indexes \<^sub>n or the empty index (default
  5027 number 1) refer to a certain fixed variable implicitly; option
  5028 show_structs controls printing of implicit structures.  Typical
  5029 applications of these concepts involve record types and locales.
  5030 
  5031 * New command 'no_syntax' removes grammar declarations (and
  5032 translations) resulting from the given syntax specification, which is
  5033 interpreted in the same manner as for the 'syntax' command.
  5034 
  5035 * 'Advanced' translation functions (parse_translation etc.) may depend
  5036 on the signature of the theory context being presently used for
  5037 parsing/printing, see also isar-ref manual.
  5038 
  5039 * Improved 'oracle' command provides a type-safe interface to turn an
  5040 ML expression of type theory -> T -> term into a primitive rule of
  5041 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5042 is already included here); see also FOL/ex/IffExample.thy;
  5043 INCOMPATIBILITY.
  5044 
  5045 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5046 before); "cI" is no longer bound, use "c.intro" instead.
  5047 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5048 axclasses vs. locales.
  5049 
  5050 * Improved internal renaming of symbolic identifiers -- attach primes
  5051 instead of base 26 numbers.
  5052 
  5053 * New flag show_question_marks controls printing of leading question
  5054 marks in schematic variable names.
  5055 
  5056 * In schematic variable names, *any* symbol following \<^isub> or
  5057 \<^isup> is now treated as part of the base name.  For example, the
  5058 following works without printing of awkward ".0" indexes:
  5059 
  5060   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5061     by simp
  5062 
  5063 * Inner syntax includes (*(*nested*) comments*).
  5064 
  5065 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5066 annotations as "(00...)".
  5067 
  5068 * Clear separation of logical types and nonterminals, where the latter
  5069 may only occur in 'syntax' specifications or type abbreviations.
  5070 Before that distinction was only partially implemented via type class
  5071 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5072 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5073 exotic syntax specifications may require further adaption
  5074 (e.g. Cube/Cube.thy).
  5075 
  5076 * Removed obsolete type class "logic", use the top sort {} instead.
  5077 Note that non-logical types should be declared as 'nonterminals'
  5078 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5079 specifications.
  5080 
  5081 * Attributes 'induct' and 'cases': type or set names may now be
  5082 locally fixed variables as well.
  5083 
  5084 * Simplifier: can now control the depth to which conditional rewriting
  5085 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5086 Limit.
  5087 
  5088 * Simplifier: simplification procedures may now take the current
  5089 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5090 interface), which is very useful for calling the Simplifier
  5091 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5092 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5093 low-level mk_simproc no longer applies Logic.varify internally, to
  5094 allow for use in a context of fixed variables.
  5095 
  5096 * thin_tac now works even if the assumption being deleted contains !!
  5097 or ==>.  More generally, erule now works even if the major premise of
  5098 the elimination rule contains !! or ==>.
  5099 
  5100 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5101 
  5102 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5103 from Pure, which contains all common declarations already.  Both
  5104 theories are defined via plain Isabelle/Isar .thy files.
  5105 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5106 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5107 use isatool fixcpure to adapt your theory and ML sources.
  5108 
  5109 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5110 selections of theorems in named facts via index ranges.
  5111 
  5112 * 'print_theorems': in theory mode, really print the difference
  5113 wrt. the last state (works for interactive theory development only),
  5114 in proof mode print all local facts (cf. 'print_facts');
  5115 
  5116 * 'hide': option '(open)' hides only base names.
  5117 
  5118 * More efficient treatment of intermediate checkpoints in interactive
  5119 theory development.
  5120 
  5121 * Code generator is now invoked via code_module (incremental code
  5122 generation) and code_library (modular code generation, ML structures
  5123 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5124 must be quoted when used as identifiers.
  5125 
  5126 * New 'value' command for reading, evaluating and printing terms using
  5127 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5128 quoted when used as identifier.
  5129 
  5130 
  5131 *** Locales ***
  5132 
  5133 * New commands for the interpretation of locale expressions in
  5134 theories (1), locales (2) and proof contexts (3).  These generate
  5135 proof obligations from the expression specification.  After the
  5136 obligations have been discharged, theorems of the expression are added
  5137 to the theory, target locale or proof context.  The synopsis of the
  5138 commands is a follows:
  5139 
  5140   (1) interpretation expr inst
  5141   (2) interpretation target < expr
  5142   (3) interpret expr inst
  5143 
  5144 Interpretation in theories and proof contexts require a parameter
  5145 instantiation of terms from the current context.  This is applied to
  5146 specifications and theorems of the interpreted expression.
  5147 Interpretation in locales only permits parameter renaming through the
  5148 locale expression.  Interpretation is smart in that interpretations
  5149 that are active already do not occur in proof obligations, neither are
  5150 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5151 inspect active interpretations of a particular locale.  For details,
  5152 see the Isar Reference manual.  Examples can be found in
  5153 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5154 
  5155 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5156 'interpret' instead.
  5157 
  5158 * New context element 'constrains' for adding type constraints to
  5159 parameters.
  5160 
  5161 * Context expressions: renaming of parameters with syntax
  5162 redeclaration.
  5163 
  5164 * Locale declaration: 'includes' disallowed.
  5165 
  5166 * Proper static binding of attribute syntax -- i.e. types / terms /
  5167 facts mentioned as arguments are always those of the locale definition
  5168 context, independently of the context of later invocations.  Moreover,
  5169 locale operations (renaming and type / term instantiation) are applied
  5170 to attribute arguments as expected.
  5171 
  5172 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5173 actual attributes; rare situations may require Attrib.attribute to
  5174 embed those attributes into Attrib.src that lack concrete syntax.
  5175 Attribute implementations need to cooperate properly with the static
  5176 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5177 Attrib.XXX_thm etc. already do the right thing without further
  5178 intervention.  Only unusual applications -- such as "where" or "of"
  5179 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5180 on the context and the facts involved -- may have to assign parsed
  5181 values to argument tokens explicitly.
  5182 
  5183 * Changed parameter management in theorem generation for long goal
  5184 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5185 theorem statement in rare situations.
  5186 
  5187 * Locale inspection command 'print_locale' omits notes elements.  Use
  5188 'print_locale!' to have them included in the output.
  5189 
  5190 
  5191 *** Provers ***
  5192 
  5193 * Provers/hypsubst.ML: improved version of the subst method, for
  5194 single-step rewriting: it now works in bound variable contexts. New is
  5195 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5196 rewrite a different subterm than the original subst method, which is
  5197 still available as 'simplesubst'.
  5198 
  5199 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5200 and quasi orders.
  5201 
  5202 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5203 reflexive-transitive closure of relations.
  5204 
  5205 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5206 limit (previously hard-coded with a value of 20) user-definable.
  5207 
  5208 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5209 is peformed already.  Object-logics merely need to finish their
  5210 initial simpset configuration as before.  INCOMPATIBILITY.
  5211 
  5212 
  5213 *** HOL ***
  5214 
  5215 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5216 
  5217   syntax (epsilon)
  5218     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5219 
  5220 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5221 and x-symbol; use option '-m epsilon' to get it actually printed.
  5222 Moreover, the mathematically important symbolic identifier \<epsilon>
  5223 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5224 
  5225 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5226 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5227 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5228 support corresponding Isar calculations.
  5229 
  5230 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5231 instead of ":".
  5232 
  5233 * theory SetInterval: changed the syntax for open intervals:
  5234 
  5235   Old       New
  5236   {..n(}    {..<n}
  5237   {)n..}    {n<..}
  5238   {m..n(}   {m..<n}
  5239   {)m..n}   {m<..n}
  5240   {)m..n(}  {m<..<n}
  5241 
  5242 The old syntax is still supported but will disappear in the next
  5243 release.  For conversion use the following Emacs search and replace
  5244 patterns (these are not perfect but work quite well):
  5245 
  5246   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5247   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5248 
  5249 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5250 equalities in commutative rings; method 'algebra' provides a generic
  5251 interface.
  5252 
  5253 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5254 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5255 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5256 be a tuple pattern.
  5257 
  5258 Some new syntax forms are available:
  5259 
  5260   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5261   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5262   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5263   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5264 
  5265 The latter form "\<Sum>x < k. e" used to be based on a separate
  5266 function "Summation", which has been discontinued.
  5267 
  5268 * theory Finite_Set: in structured induction proofs, the insert case
  5269 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5270 (insert F x)'.
  5271 
  5272 * The 'refute' command has been extended to support a much larger
  5273 fragment of HOL, including axiomatic type classes, constdefs and
  5274 typedefs, inductive datatypes and recursion.
  5275 
  5276 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5277 Requires zChaff with proof generation to be installed.  See
  5278 HOL/ex/SAT_Examples.thy for examples.
  5279 
  5280 * Datatype induction via method 'induct' now preserves the name of the
  5281 induction variable. For example, when proving P(xs::'a list) by
  5282 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5283 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5284 in unstructured proof scripts.
  5285 
  5286 * Reworked implementation of records.  Improved scalability for
  5287 records with many fields, avoiding performance problems for type
  5288 inference. Records are no longer composed of nested field types, but
  5289 of nested extension types. Therefore the record type only grows linear
  5290 in the number of extensions and not in the number of fields.  The
  5291 top-level (users) view on records is preserved.  Potential
  5292 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5293 old record representation. The type generated for a record is called
  5294 <record_name>_ext_type.
  5295 
  5296 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5297 proofs triggered by a record definition or a simproc (if
  5298 quick_and_dirty is enabled).  Definitions of large records can take
  5299 quite long.
  5300 
  5301 New simproc record_upd_simproc for simplification of multiple record
  5302 updates enabled by default.  Moreover, trivial updates are also
  5303 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5304 occasionally, since simplification is more powerful by default.
  5305 
  5306 * typedef: proper support for polymorphic sets, which contain extra
  5307 type-variables in the term.
  5308 
  5309 * Simplifier: automatically reasons about transitivity chains
  5310 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5311 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5312 old proofs break occasionally as simplification may now solve more
  5313 goals than previously.
  5314 
  5315 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5316 present.  Works for all partial orders (class "order"), in particular
  5317 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5318 just like y <= x.
  5319 
  5320 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5321 bound variable or a constant then the let is unfolded.  Otherwise
  5322 first a is simplified to b, and then f b is simplified to g. If
  5323 possible we abstract b from g arriving at "let x = b in h x",
  5324 otherwise we unfold the let and arrive at g.  The simproc can be
  5325 enabled/disabled by the reference use_let_simproc.  Potential
  5326 INCOMPATIBILITY since simplification is more powerful by default.
  5327 
  5328 * Classical reasoning: the meson method now accepts theorems as arguments.
  5329 
  5330 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5331 jobs to provide advice on the provability of subgoals.
  5332 
  5333 * Theory OrderedGroup and Ring_and_Field: various additions and
  5334 improvements to faciliate calculations involving equalities and
  5335 inequalities.
  5336 
  5337 The following theorems have been eliminated or modified
  5338 (INCOMPATIBILITY):
  5339 
  5340   abs_eq             now named abs_of_nonneg
  5341   abs_of_ge_0        now named abs_of_nonneg
  5342   abs_minus_eq       now named abs_of_nonpos
  5343   imp_abs_id         now named abs_of_nonneg
  5344   imp_abs_neg_id     now named abs_of_nonpos
  5345   mult_pos           now named mult_pos_pos
  5346   mult_pos_le        now named mult_nonneg_nonneg
  5347   mult_pos_neg_le    now named mult_nonneg_nonpos
  5348   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5349   mult_neg           now named mult_neg_neg
  5350   mult_neg_le        now named mult_nonpos_nonpos
  5351 
  5352 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5353      
  5354      zero_le_square
  5355      not_square_less_zero 
  5356 
  5357   The following lemmas have been deleted from Real/RealPow:
  5358   
  5359      realpow_zero_zero
  5360      realpow_two
  5361      realpow_less
  5362      zero_le_power
  5363      realpow_two_le
  5364      abs_realpow_two
  5365      realpow_two_abs     
  5366 
  5367 * Theory Parity: added rules for simplifying exponents.
  5368 
  5369 * Theory List:
  5370 
  5371 The following theorems have been eliminated or modified
  5372 (INCOMPATIBILITY):
  5373 
  5374   list_all_Nil       now named list_all.simps(1)
  5375   list_all_Cons      now named list_all.simps(2)
  5376   list_all_conv      now named list_all_iff
  5377   set_mem_eq         now named mem_iff
  5378 
  5379 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5380 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5381 
  5382 
  5383 *** HOL-Complex ***
  5384 
  5385 * Theory RealDef: better support for embedding natural numbers and
  5386 integers in the reals.
  5387 
  5388 The following theorems have been eliminated or modified
  5389 (INCOMPATIBILITY):
  5390 
  5391   exp_ge_add_one_self  now requires no hypotheses
  5392   real_of_int_add      reversed direction of equality (use [symmetric])
  5393   real_of_int_minus    reversed direction of equality (use [symmetric])
  5394   real_of_int_diff     reversed direction of equality (use [symmetric])
  5395   real_of_int_mult     reversed direction of equality (use [symmetric])
  5396 
  5397 * Theory RComplete: expanded support for floor and ceiling functions.
  5398 
  5399 * Theory Ln is new, with properties of the natural logarithm
  5400 
  5401 * Hyperreal: There is a new type constructor "star" for making
  5402 nonstandard types.  The old type names are now type synonyms:
  5403 
  5404   hypreal = real star
  5405   hypnat = nat star
  5406   hcomplex = complex star
  5407 
  5408 * Hyperreal: Many groups of similarly-defined constants have been
  5409 replaced by polymorphic versions (INCOMPATIBILITY):
  5410 
  5411   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5412 
  5413   starset      <-- starsetNat, starsetC
  5414   *s*          <-- *sNat*, *sc*
  5415   starset_n    <-- starsetNat_n, starsetC_n
  5416   *sn*         <-- *sNatn*, *scn*
  5417   InternalSets <-- InternalNatSets, InternalCSets
  5418 
  5419   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5420   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5421   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5422   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5423   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5424 
  5425 * Hyperreal: Many type-specific theorems have been removed in favor of
  5426 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5427 
  5428   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5429   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5430   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5431   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5432   right_minus <-- hypreal_add_minus
  5433   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5434   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5435   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5436   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5437   mult_1_right <-- hcomplex_mult_one_right
  5438   mult_zero_left <-- hcomplex_mult_zero_left
  5439   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5440   right_distrib <-- hypnat_add_mult_distrib2
  5441   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5442   right_inverse <-- hypreal_mult_inverse
  5443   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5444   order_refl <-- {hypreal,hypnat}_le_refl
  5445   order_trans <-- {hypreal,hypnat}_le_trans
  5446   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5447   order_less_le <-- {hypreal,hypnat}_less_le
  5448   linorder_linear <-- {hypreal,hypnat}_le_linear
  5449   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5450   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5451   add_nonneg_nonneg <-- hypreal_le_add_order
  5452 
  5453 * Hyperreal: Separate theorems having to do with type-specific
  5454 versions of constants have been merged into theorems that apply to the
  5455 new polymorphic constants (INCOMPATIBILITY):
  5456 
  5457   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5458   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5459   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5460   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5461   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5462   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5463   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5464   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5465   STAR_diff <-- {STAR,STARC}_diff
  5466   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5467     STARC_hcomplex_of_complex}_image_subset
  5468   starset_n_Un <-- starset{Nat,C}_n_Un
  5469   starset_n_Int <-- starset{Nat,C}_n_Int
  5470   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5471   starset_n_diff <-- starset{Nat,C}_n_diff
  5472   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5473   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5474   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5475   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5476   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5477   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5478   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5479   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5480   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5481   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5482   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5483   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5484   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5485   starfun_diff <-- starfun{C,RC,CR}_diff
  5486   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5487   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5488   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5489   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5490   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5491   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5492   starfun_Id <-- starfunC_Id
  5493   starfun_approx <-- starfun{Nat,CR}_approx
  5494   starfun_capprox <-- starfun{C,RC}_capprox
  5495   starfun_abs <-- starfunNat_rabs
  5496   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5497   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5498   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5499   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5500   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5501   starfun_add_approx <-- starfunCR_add_approx
  5502   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5503   starfun_divide <-- starfun{C,CR,RC}_divide
  5504   starfun_n <-- starfun{Nat,C}_n
  5505   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5506   starfun_n_add <-- starfun{Nat,C}_n_add
  5507   starfun_n_add_minus <-- starfunNat_n_add_minus
  5508   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5509   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5510   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5511 
  5512   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5513   star_n_minus <-- {hypreal,hcomplex}_minus
  5514   star_n_diff <-- {hypreal,hcomplex}_diff
  5515   star_n_mult <-- {hypreal,hcomplex}_mult
  5516   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5517   star_n_le <-- {hypreal,hypnat}_le
  5518   star_n_less <-- {hypreal,hypnat}_less
  5519   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5520   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5521   star_n_abs <-- hypreal_hrabs
  5522   star_n_divide <-- hcomplex_divide
  5523 
  5524   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5525   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5526   star_of_diff <-- hypreal_of_real_diff
  5527   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5528   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5529   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5530   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5531   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5532   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5533   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5534   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5535   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5536   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5537   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5538   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5539   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5540   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5541   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5542   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5543   star_of_power <-- hypreal_of_real_power
  5544   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5545 
  5546 * Hyperreal: new method "transfer" that implements the transfer
  5547 principle of nonstandard analysis. With a subgoal that mentions
  5548 nonstandard types like "'a star", the command "apply transfer"
  5549 replaces it with an equivalent one that mentions only standard types.
  5550 To be successful, all free variables must have standard types; non-
  5551 standard variables must have explicit universal quantifiers.
  5552 
  5553 * Hyperreal: A theory of Taylor series.
  5554 
  5555 
  5556 *** HOLCF ***
  5557 
  5558 * Discontinued special version of 'constdefs' (which used to support
  5559 continuous functions) in favor of the general Pure one with full
  5560 type-inference.
  5561 
  5562 * New simplification procedure for solving continuity conditions; it
  5563 is much faster on terms with many nested lambda abstractions (cubic
  5564 instead of exponential time).
  5565 
  5566 * New syntax for domain package: selector names are now optional.
  5567 Parentheses should be omitted unless argument is lazy, for example:
  5568 
  5569   domain 'a stream = cons "'a" (lazy "'a stream")
  5570 
  5571 * New command 'fixrec' for defining recursive functions with pattern
  5572 matching; defining multiple functions with mutual recursion is also
  5573 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5574 sinr, or any data constructor defined by the domain package. The given
  5575 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5576 syntax and examples.
  5577 
  5578 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5579 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5580 but the proof obligation additionally includes an admissibility
  5581 requirement. The packages generate instances of class cpo or pcpo,
  5582 with continuity and strictness theorems for Rep and Abs.
  5583 
  5584 * HOLCF: Many theorems have been renamed according to a more standard naming
  5585 scheme (INCOMPATIBILITY):
  5586 
  5587   foo_inject:  "foo$x = foo$y ==> x = y"
  5588   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5589   foo_less:    "(foo$x << foo$y) = (x << y)"
  5590   foo_strict:  "foo$UU = UU"
  5591   foo_defined: "... ==> foo$x ~= UU"
  5592   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5593 
  5594 
  5595 *** ZF ***
  5596 
  5597 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5598 including the First Isomorphism Theorem (on quotienting by the kernel
  5599 of a homomorphism).
  5600 
  5601 * ZF/Simplifier: install second copy of type solver that actually
  5602 makes use of TC rules declared to Isar proof contexts (or locales);
  5603 the old version is still required for ML proof scripts.
  5604 
  5605 
  5606 *** Cube ***
  5607 
  5608 * Converted to Isar theory format; use locales instead of axiomatic
  5609 theories.
  5610 
  5611 
  5612 *** ML ***
  5613 
  5614 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5615 for ||>, ||>>, |>>,
  5616 
  5617 * Pure/library.ML no longer defines its own option datatype, but uses
  5618 that of the SML basis, which has constructors NONE and SOME instead of
  5619 None and Some, as well as exception Option.Option instead of OPTION.
  5620 The functions the, if_none, is_some, is_none have been adapted
  5621 accordingly, while Option.map replaces apsome.
  5622 
  5623 * Pure/library.ML: the exception LIST has been given up in favour of
  5624 the standard exceptions Empty and Subscript, as well as
  5625 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5626 superceded by the standard hd and tl functions etc.
  5627 
  5628 A number of basic list functions are no longer exported to the ML
  5629 toplevel, as they are variants of predefined functions.  The following
  5630 suggests how one can translate existing code:
  5631 
  5632     rev_append xs ys = List.revAppend (xs, ys)
  5633     nth_elem (i, xs) = List.nth (xs, i)
  5634     last_elem xs = List.last xs
  5635     flat xss = List.concat xss
  5636     seq fs = List.app fs
  5637     partition P xs = List.partition P xs
  5638     mapfilter f xs = List.mapPartial f xs
  5639 
  5640 * Pure/library.ML: several combinators for linear functional
  5641 transformations, notably reverse application and composition:
  5642 
  5643   x |> f                f #> g
  5644   (x, y) |-> f          f #-> g
  5645 
  5646 * Pure/library.ML: introduced/changed precedence of infix operators:
  5647 
  5648   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5649   infix 2 ?;
  5650   infix 3 o oo ooo oooo;
  5651   infix 4 ~~ upto downto;
  5652 
  5653 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5654 infix operators.
  5655 
  5656 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5657 fold_map support linear functional transformations and nesting.  For
  5658 example:
  5659 
  5660   fold f [x1, ..., xN] y =
  5661     y |> f x1 |> ... |> f xN
  5662 
  5663   (fold o fold) f [xs1, ..., xsN] y =
  5664     y |> fold f xs1 |> ... |> fold f xsN
  5665 
  5666   fold f [x1, ..., xN] =
  5667     f x1 #> ... #> f xN
  5668 
  5669   (fold o fold) f [xs1, ..., xsN] =
  5670     fold f xs1 #> ... #> fold f xsN
  5671 
  5672 * Pure/library.ML: the following selectors on type 'a option are
  5673 available:
  5674 
  5675   the:               'a option -> 'a  (*partial*)
  5676   these:             'a option -> 'a  where 'a = 'b list
  5677   the_default: 'a -> 'a option -> 'a
  5678   the_list:          'a option -> 'a list
  5679 
  5680 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5681 basic operations for association lists, following natural argument
  5682 order; moreover the explicit equality predicate passed here avoids
  5683 potentially expensive polymorphic runtime equality checks.
  5684 The old functions may be expressed as follows:
  5685 
  5686   assoc = uncurry (AList.lookup (op =))
  5687   assocs = these oo AList.lookup (op =)
  5688   overwrite = uncurry (AList.update (op =)) o swap
  5689 
  5690 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5691 
  5692   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5693   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5694 
  5695 replacing make_keylist and keyfilter (occassionally used)
  5696 Naive rewrites:
  5697 
  5698   make_keylist = AList.make
  5699   keyfilter = AList.find (op =)
  5700 
  5701 * eq_fst and eq_snd now take explicit equality parameter, thus
  5702   avoiding eqtypes. Naive rewrites:
  5703 
  5704     eq_fst = eq_fst (op =)
  5705     eq_snd = eq_snd (op =)
  5706 
  5707 * Removed deprecated apl and apr (rarely used).
  5708   Naive rewrites:
  5709 
  5710     apl (n, op) =>>= curry op n
  5711     apr (op, m) =>>= fn n => op (n, m)
  5712 
  5713 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5714 provides a reasonably efficient light-weight implementation of sets as
  5715 lists.
  5716 
  5717 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5718 few new operations; existing lookup and update are now curried to
  5719 follow natural argument order (for use with fold etc.);
  5720 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5721 
  5722 * Pure/General: output via the Isabelle channels of
  5723 writeln/warning/error etc. is now passed through Output.output, with a
  5724 hook for arbitrary transformations depending on the print_mode
  5725 (cf. Output.add_mode -- the first active mode that provides a output
  5726 function wins).  Already formatted output may be embedded into further
  5727 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5728 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5729 accommodate easy composition of diagnostic messages etc.  Programmers
  5730 rarely need to care about Output.output or Output.raw at all, with
  5731 some notable exceptions: Output.output is required when bypassing the
  5732 standard channels (writeln etc.), or in token translations to produce
  5733 properly formatted results; Output.raw is required when capturing
  5734 already output material that will eventually be presented to the user
  5735 a second time.  For the default print mode, both Output.output and
  5736 Output.raw have no effect.
  5737 
  5738 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5739 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5740 cumulative results are displayed at the end of a batch session.
  5741 
  5742 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5743 replaced by File.platform_path and File.shell_path (with appropriate
  5744 hooks).  This provides a clean interface for unusual systems where the
  5745 internal and external process view of file names are different.
  5746 
  5747 * Pure: more efficient orders for basic syntactic entities: added
  5748 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5749 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5750 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5751 orders now -- potential INCOMPATIBILITY for code that depends on a
  5752 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5753 Library.sort_strings on result).
  5754 
  5755 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5756 fold_types traverse types/terms from left to right, observing natural
  5757 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5758 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5759 
  5760 * Pure: name spaces have been refined, with significant changes of the
  5761 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5762 to extern(_table).  The plain name entry path is superceded by a
  5763 general 'naming' context, which also includes the 'policy' to produce
  5764 a fully qualified name and external accesses of a fully qualified
  5765 name; NameSpace.extend is superceded by context dependent
  5766 Sign.declare_name.  Several theory and proof context operations modify
  5767 the naming context.  Especially note Theory.restore_naming and
  5768 ProofContext.restore_naming to get back to a sane state; note that
  5769 Theory.add_path is no longer sufficient to recover from
  5770 Theory.absolute_path in particular.
  5771 
  5772 * Pure: new flags short_names (default false) and unique_names
  5773 (default true) for controlling output of qualified names.  If
  5774 short_names is set, names are printed unqualified.  If unique_names is
  5775 reset, the name prefix is reduced to the minimum required to achieve
  5776 the original result when interning again, even if there is an overlap
  5777 with earlier declarations.
  5778 
  5779 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5780 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5781 (useful for printing error messages).  INCOMPATIBILITY.
  5782 
  5783 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5784 Theory.theory are now identified, referring to the universal
  5785 Context.theory (see Pure/context.ML).  Actual signature and theory
  5786 content is managed as theory data.  The old code and interfaces were
  5787 spread over many files and structures; the new arrangement introduces
  5788 considerable INCOMPATIBILITY to gain more clarity:
  5789 
  5790   Context -- theory management operations (name, identity, inclusion,
  5791     parents, ancestors, merge, etc.), plus generic theory data;
  5792 
  5793   Sign -- logical signature and syntax operations (declaring consts,
  5794     types, etc.), plus certify/read for common entities;
  5795 
  5796   Theory -- logical theory operations (stating axioms, definitions,
  5797     oracles), plus a copy of logical signature operations (consts,
  5798     types, etc.); also a few basic management operations (Theory.copy,
  5799     Theory.merge, etc.)
  5800 
  5801 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5802 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5803 for convenience -- they merely return the theory.
  5804 
  5805 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5806 
  5807 * Pure: the Isar proof context type is already defined early in Pure
  5808 as Context.proof (note that ProofContext.context and Proof.context are
  5809 aliases, where the latter is the preferred name).  This enables other
  5810 Isabelle components to refer to that type even before Isar is present.
  5811 
  5812 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5813 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5814 any of these kinds.  For example, Sign.intern typeK is now
  5815 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5816 Theory.hide_types.  Also note that former
  5817 Theory.hide_classes/types/consts are now
  5818 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5819 internalize their arguments!  INCOMPATIBILITY.
  5820 
  5821 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5822 datatype thmref (with constructors Name and NameSelection) instead of
  5823 plain string -- INCOMPATIBILITY;
  5824 
  5825 * Pure: cases produced by proof methods specify options, where NONE
  5826 means to remove case bindings -- INCOMPATIBILITY in
  5827 (RAW_)METHOD_CASES.
  5828 
  5829 * Pure: the following operations retrieve axioms or theorems from a
  5830 theory node or theory hierarchy, respectively:
  5831 
  5832   Theory.axioms_of: theory -> (string * term) list
  5833   Theory.all_axioms_of: theory -> (string * term) list
  5834   PureThy.thms_of: theory -> (string * thm) list
  5835   PureThy.all_thms_of: theory -> (string * thm) list
  5836 
  5837 * Pure: print_tac now outputs the goal through the trace channel.
  5838 
  5839 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5840 Reference Toplevel.debug (default false) controls detailed printing
  5841 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5842 controls execution profiling -- set to 1 for time and 2 for space
  5843 (both increase the runtime).
  5844 
  5845 * Isar session: The initial use of ROOT.ML is now always timed,
  5846 i.e. the log will show the actual process times, in contrast to the
  5847 elapsed wall-clock time that the outer shell wrapper produces.
  5848 
  5849 * Simplifier: improved handling of bound variables (nameless
  5850 representation, avoid allocating new strings).  Simprocs that invoke
  5851 the Simplifier recursively should use Simplifier.inherit_bounds to
  5852 avoid local name clashes.  Failure to do so produces warnings
  5853 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5854 for further details.
  5855 
  5856 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5857 bindings for all theorems stored within a given theory; this may help
  5858 in porting non-Isar theories to Isar ones, while keeping ML proof
  5859 scripts for the time being.
  5860 
  5861 * ML operator HTML.with_charset specifies the charset begin used for
  5862 generated HTML files.  For example:
  5863 
  5864   HTML.with_charset "utf-8" use_thy "Hebrew";
  5865   HTML.with_charset "utf-8" use_thy "Chinese";
  5866 
  5867 
  5868 *** System ***
  5869 
  5870 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5871 isabelle, isatool etc.).
  5872 
  5873 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5874 isatool doc, isatool mkdir, display_drafts etc.).
  5875 
  5876 * isatool usedir: option -f allows specification of the ML file to be
  5877 used by Isabelle; default is ROOT.ML.
  5878 
  5879 * New isatool version outputs the version identifier of the Isabelle
  5880 distribution being used.
  5881 
  5882 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5883 (containing Boolean satisfiability problems) into Isabelle/HOL
  5884 theories.
  5885 
  5886 
  5887 
  5888 New in Isabelle2004 (April 2004)
  5889 --------------------------------
  5890 
  5891 *** General ***
  5892 
  5893 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5894   Replaces linorder.ML.
  5895 
  5896 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5897   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5898   (\<a>...\<z>), are now considered normal letters, and can therefore
  5899   be used anywhere where an ASCII letter (a...zA...Z) has until
  5900   now. COMPATIBILITY: This obviously changes the parsing of some
  5901   terms, especially where a symbol has been used as a binder, say
  5902   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5903   as an identifier.  Fix it by inserting a space around former
  5904   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5905   existing theory and ML files.
  5906 
  5907 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5908 
  5909 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5910   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5911   a normal (but invisible) letter. For multiple letter subscripts repeat
  5912   \<^isub> like this: x\<^isub>1\<^isub>2.
  5913 
  5914 * Pure: There are now sub-/superscripts that can span more than one
  5915   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5916   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5917   superscript. The new control characters are not identifier parts.
  5918 
  5919 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5920   content of "..." to the latex file instead of \isacntrl... . The "..."
  5921   may consist of any printable characters excluding the end bracket >.
  5922 
  5923 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5924   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5925   declare constants "final", which prevents their being given a definition
  5926   later.  It is useful for constants whose behaviour is fixed axiomatically
  5927   rather than definitionally, such as the meta-logic connectives.
  5928 
  5929 * Pure: 'instance' now handles general arities with general sorts
  5930   (i.e. intersections of classes),
  5931 
  5932 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5933   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5934   It can be changed to alter the colors/layout of generated pages.
  5935 
  5936 
  5937 *** Isar ***
  5938 
  5939 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5940   cut_tac, subgoal_tac and thin_tac:
  5941   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5942     locales are no longer forced to write Isar proof scripts.
  5943     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5944     emulations.
  5945   - INCOMPATIBILITY: names of variables to be instantiated may no
  5946     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5947     This is consistent with the instantiation attribute "where".
  5948 
  5949 * Attributes "where" and "of":
  5950   - Now take type variables of instantiated theorem into account when reading
  5951     the instantiation string.  This fixes a bug that caused instantiated
  5952     theorems to have too special types in some circumstances.
  5953   - "where" permits explicit instantiations of type variables.
  5954 
  5955 * Calculation commands "moreover" and "also" no longer interfere with
  5956   current facts ("this"), admitting arbitrary combinations with "then"
  5957   and derived forms.
  5958 
  5959 * Locales:
  5960   - Goal statements involving the context element "includes" no longer
  5961     generate theorems with internal delta predicates (those ending on
  5962     "_axioms") in the premise.
  5963     Resolve particular premise with <locale>.intro to obtain old form.
  5964   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5965     specification and "includes" elements in goal statement.
  5966   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5967     [intro?] and [elim?] (respectively) by default.
  5968   - Experimental command for instantiation of locales in proof contexts:
  5969         instantiate <label>[<attrs>]: <loc>
  5970     Instantiates locale <loc> and adds all its theorems to the current context
  5971     taking into account their attributes.  Label and attrs are optional
  5972     modifiers, like in theorem declarations.  If present, names of
  5973     instantiated theorems are qualified with <label>, and the attributes
  5974     <attrs> are applied after any attributes these theorems might have already.
  5975       If the locale has assumptions, a chained fact of the form
  5976     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5977     are derived.  The command does not support old-style locales declared
  5978     with "locale (open)".
  5979       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5980 
  5981 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5982   (Isar) contexts.
  5983 
  5984 
  5985 *** HOL ***
  5986 
  5987 * Proof import: new image HOL4 contains the imported library from
  5988   the HOL4 system with about 2500 theorems. It is imported by
  5989   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5990   can be used like any other Isabelle image.  See
  5991   HOL/Import/HOL/README for more information.
  5992 
  5993 * Simplifier:
  5994   - Much improved handling of linear and partial orders.
  5995     Reasoners for linear and partial orders are set up for type classes
  5996     "linorder" and "order" respectively, and are added to the default simpset
  5997     as solvers.  This means that the simplifier can build transitivity chains
  5998     to solve goals from the assumptions.
  5999   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6000     of blast or auto after simplification become unnecessary because the goal
  6001     is solved by simplification already.
  6002 
  6003 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6004     all proved in axiomatic type classes for semirings, rings and fields.
  6005 
  6006 * Numerics:
  6007   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6008     now formalized using the Ring_and_Field theory mentioned above.
  6009   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6010     than before, because now they are set up once in a generic manner.
  6011   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6012     Look for the general versions in Ring_and_Field (and Power if they concern
  6013     exponentiation).
  6014 
  6015 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6016 
  6017 * Records:
  6018   - Record types are now by default printed with their type abbreviation
  6019     instead of the list of all field types. This can be configured via
  6020     the reference "print_record_type_abbr".
  6021   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6022     (not enabled by default).
  6023   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6024     EX x. x = sel r to True (not enabled by default).
  6025   - Tactic "record_split_simp_tac" to split and simplify records added.
  6026 
  6027 * 'specification' command added, allowing for definition by
  6028   specification.  There is also an 'ax_specification' command that
  6029   introduces the new constants axiomatically.
  6030 
  6031 * arith(_tac) is now able to generate counterexamples for reals as well.
  6032 
  6033 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6034 
  6035 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6036   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6037 
  6038 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6039   matrix theory to linear programming.
  6040 
  6041 * Unions and Intersections:
  6042   The latex output syntax of UN and INT has been changed
  6043   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6044   i.e. the index formulae has become a subscript.
  6045   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6046 
  6047 * Unions and Intersections over Intervals:
  6048   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6049   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6050   like in normal math, and corresponding versions for < and for intersection.
  6051 
  6052 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6053   lexicographic dictonary ordering has been added as "lexord".
  6054 
  6055 * ML: the legacy theory structures Int and List have been removed. They had
  6056   conflicted with ML Basis Library structures having the same names.
  6057 
  6058 * 'refute' command added to search for (finite) countermodels.  Only works
  6059   for a fragment of HOL.  The installation of an external SAT solver is
  6060   highly recommended.  See "HOL/Refute.thy" for details.
  6061 
  6062 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6063   formulae under an assignment of free variables to random values.
  6064   In contrast to 'refute', it can deal with inductive datatypes,
  6065   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6066   for examples.
  6067 
  6068 
  6069 *** HOLCF ***
  6070 
  6071 * Streams now come with concatenation and are part of the HOLCF image
  6072 
  6073 
  6074 
  6075 New in Isabelle2003 (May 2003)
  6076 ------------------------------
  6077 
  6078 *** General ***
  6079 
  6080 * Provers/simplifier:
  6081 
  6082   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6083     Assumptions are now subject to complete mutual simplification,
  6084     not just from left to right. The simplifier now preserves
  6085     the order of assumptions.
  6086 
  6087     Potential INCOMPATIBILITY:
  6088 
  6089     -- simp sometimes diverges where the old version did
  6090        not, e.g. invoking simp on the goal
  6091 
  6092         [| P (f x); y = x; f x = f y |] ==> Q
  6093 
  6094        now gives rise to the infinite reduction sequence
  6095 
  6096         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6097 
  6098        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6099        kind of problem.
  6100 
  6101     -- Tactics combining classical reasoner and simplification (such as auto)
  6102        are also affected by this change, because many of them rely on
  6103        simp. They may sometimes diverge as well or yield a different numbers
  6104        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6105        in case of problems. Sometimes subsequent calls to the classical
  6106        reasoner will fail because a preceeding call to the simplifier too
  6107        eagerly simplified the goal, e.g. deleted redundant premises.
  6108 
  6109   - The simplifier trace now shows the names of the applied rewrite rules
  6110 
  6111   - You can limit the number of recursive invocations of the simplifier
  6112     during conditional rewriting (where the simplifie tries to solve the
  6113     conditions before applying the rewrite rule):
  6114     ML "simp_depth_limit := n"
  6115     where n is an integer. Thus you can force termination where previously
  6116     the simplifier would diverge.
  6117 
  6118   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6119 
  6120   - No longer aborts on failed congruence proof.  Instead, the
  6121     congruence is ignored.
  6122 
  6123 * Pure: New generic framework for extracting programs from constructive
  6124   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6125   as HOL/Extraction for some case studies.
  6126 
  6127 * Pure: The main goal of the proof state is no longer shown by default, only
  6128 the subgoals. This behaviour is controlled by a new flag.
  6129    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6130 (ML: Proof.show_main_goal).
  6131 
  6132 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6133 rules whose conclusion matches subgoal 1:
  6134       PG menu: Isabelle/Isar -> Show me -> matching rules
  6135 The rules are ordered by how closely they match the subgoal.
  6136 In particular, rules that solve a subgoal outright are displayed first
  6137 (or rather last, the way they are printed).
  6138 (ML: ProofGeneral.print_intros())
  6139 
  6140 * Pure: New flag trace_unify_fail causes unification to print
  6141 diagnostic information (PG: in trace buffer) when it fails. This is
  6142 useful for figuring out why single step proofs like rule, erule or
  6143 assumption failed.
  6144 
  6145 * Pure: Locale specifications now produce predicate definitions
  6146 according to the body of text (covering assumptions modulo local
  6147 definitions); predicate "loc_axioms" covers newly introduced text,
  6148 while "loc" is cumulative wrt. all included locale expressions; the
  6149 latter view is presented only on export into the global theory
  6150 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6151 on the old view without predicates;
  6152 
  6153 * Pure: predefined locales "var" and "struct" are useful for sharing
  6154 parameters (as in CASL, for example); just specify something like
  6155 ``var x + var y + struct M'' as import;
  6156 
  6157 * Pure: improved thms_containing: proper indexing of facts instead of
  6158 raw theorems; check validity of results wrt. current name space;
  6159 include local facts of proof configuration (also covers active
  6160 locales), cover fixed variables in index; may use "_" in term
  6161 specification; an optional limit for the number of printed facts may
  6162 be given (the default is 40);
  6163 
  6164 * Pure: disallow duplicate fact bindings within new-style theory files
  6165 (batch-mode only);
  6166 
  6167 * Provers: improved induct method: assumptions introduced by case
  6168 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6169 the goal statement); "foo" still refers to all facts collectively;
  6170 
  6171 * Provers: the function blast.overloaded has been removed: all constants
  6172 are regarded as potentially overloaded, which improves robustness in exchange
  6173 for slight decrease in efficiency;
  6174 
  6175 * Provers/linorder: New generic prover for transitivity reasoning over
  6176 linear orders.  Note: this prover is not efficient!
  6177 
  6178 * Isar: preview of problems to finish 'show' now produce an error
  6179 rather than just a warning (in interactive mode);
  6180 
  6181 
  6182 *** HOL ***
  6183 
  6184 * arith(_tac)
  6185 
  6186  - Produces a counter example if it cannot prove a goal.
  6187    Note that the counter example may be spurious if the goal is not a formula
  6188    of quantifier-free linear arithmetic.
  6189    In ProofGeneral the counter example appears in the trace buffer.
  6190 
  6191  - Knows about div k and mod k where k is a numeral of type nat or int.
  6192 
  6193  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6194    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6195    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6196 
  6197 * simp's arithmetic capabilities have been enhanced a bit: it now
  6198 takes ~= in premises into account (by performing a case split);
  6199 
  6200 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6201 are distributed over a sum of terms;
  6202 
  6203 * New tactic "trans_tac" and method "trans" instantiate
  6204 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6205 "<=", "<" and "=").
  6206 
  6207 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6208 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6209 
  6210 * 'typedef' command has new option "open" to suppress the set
  6211 definition;
  6212 
  6213 * functions Min and Max on finite sets have been introduced (theory
  6214 Finite_Set);
  6215 
  6216 * attribute [symmetric] now works for relations as well; it turns
  6217 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6218 
  6219 * induct over a !!-quantified statement (say !!x1..xn):
  6220   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6221 
  6222 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6223 %x. None. Warning: empty_def now refers to the previously hidden definition
  6224 of the empty set.
  6225 
  6226 * Algebra: formalization of classical algebra.  Intended as base for
  6227 any algebraic development in Isabelle.  Currently covers group theory
  6228 (up to Sylow's theorem) and ring theory (Un