NEWS
author oheimb
Mon Oct 19 13:50:25 1998 +0200 (1998-10-19)
changeset 5671 da670b37857e
parent 5657 1a6c9c6a3f8e
child 5705 56f2030c46c6
permissions -rw-r--r--
layout
wenzelm@5363
     1
wenzelm@5363
     2
Isabelle NEWS -- history user-relevant changes
wenzelm@5363
     3
==============================================
wenzelm@2553
     4
wenzelm@4981
     5
New in this Isabelle version
wenzelm@4981
     6
----------------------------
oheimb@4649
     7
wenzelm@5127
     8
*** Overview of INCOMPATIBILITIES (see below for more details) ***
wenzelm@4842
     9
wenzelm@5217
    10
* several changes of proof tools;
wenzelm@5207
    11
wenzelm@5373
    12
* HOL: new version of inductive and datatype;
wenzelm@5373
    13
wenzelm@5217
    14
* HOL: major changes to the inductive and datatype packages;
berghofe@5214
    15
wenzelm@5217
    16
* HOL: renamed r^-1 to 'converse' from 'inverse'; `inj_onto' is now
wenzelm@5217
    17
called `inj_on';
paulson@5160
    18
nipkow@5275
    19
* HOL: removed duplicate thms in Arith:
nipkow@5275
    20
  less_imp_add_less  should be replaced by  trans_less_add1
nipkow@5275
    21
  le_imp_add_le      should be replaced by  trans_le_add1
paulson@5160
    22
paulson@5490
    23
* HOL: unary - is now overloaded (new type constraints may be required);
paulson@5490
    24
paulson@5541
    25
* HOL and ZF: unary minus for integers is now #- instead of #~.  In ZF, 
paulson@5541
    26
  expressions such as n#-1 must be changed to n#- 1, since #-1 is now taken
paulson@5541
    27
  as an integer constant.
paulson@5541
    28
wenzelm@5397
    29
* Pure: ML function 'theory_of' replaced by 'theory';
wenzelm@5397
    30
wenzelm@5363
    31
wenzelm@5127
    32
*** Proof tools ***
nipkow@4880
    33
nipkow@5657
    34
* Simplifier:
nipkow@5657
    35
  1. Asm_full_simp_tac is now more aggressive.
nipkow@5657
    36
     1. It will sometimes reorient premises if that increases their power to
nipkow@5657
    37
        simplify.
nipkow@5657
    38
     2. It does no longer proceed strictly from left to right but may also
nipkow@5657
    39
        rotate premises to achieve further simplification.
nipkow@5657
    40
     For compatibility reasons there is now Asm_lr_simp_tac which is like the
nipkow@5657
    41
     old Asm_full_simp_tac in that it does not rotate premises.
nipkow@5657
    42
  2. The simplifier now knows a little bit about nat-arithmetic.
nipkow@4880
    43
wenzelm@5127
    44
* Classical reasoner: wrapper mechanism for the classical reasoner now
wenzelm@5127
    45
allows for selected deletion of wrappers, by introduction of names for
wenzelm@5127
    46
wrapper functionals.  This implies that addbefore, addSbefore,
wenzelm@5127
    47
addaltern, and addSaltern now take a pair (name, tactic) as argument,
wenzelm@5127
    48
and that adding two tactics with the same name overwrites the first
wenzelm@5127
    49
one (emitting a warning).
oheimb@4824
    50
  type wrapper = (int -> tactic) -> (int -> tactic)
oheimb@4649
    51
  setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
oheimb@4824
    52
  addWrapper, addSWrapper: claset * (string * wrapper) -> claset
oheimb@4824
    53
  delWrapper, delSWrapper: claset *  string            -> claset
oheimb@4649
    54
  getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
oheimb@4649
    55
oheimb@5671
    56
* Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE semantics;
oheimb@5524
    57
  addbefore now affects only the unsafe part of step_tac etc.;
oheimb@5671
    58
  This affects addss/auto_tac/force_tac,so EXISTING (INSTABLE) PROOFS MAY FAIL,
oheimb@5671
    59
  but proofs should be fixable easily, e.g. by replacing Auto_tac by Force_tac.
oheimb@5524
    60
oheimb@5524
    61
* Classical reasoner: setwrapper to setWrapper and compwrapper to compWrapper; 
oheimb@5524
    62
  added safe wrapper (and access functions for it);
oheimb@5524
    63
wenzelm@5127
    64
* HOL/split_all_tac is now much faster and fails if there is nothing
wenzelm@5127
    65
to split.  Existing (fragile) proofs may require adaption because the
wenzelm@5127
    66
order and the names of the automatically generated variables have
wenzelm@5127
    67
changed.  split_all_tac has moved within claset() from unsafe wrappers
wenzelm@5127
    68
to safe wrappers, which means that !!-bound variables are split much
wenzelm@5127
    69
more aggressively, and safe_tac and clarify_tac now split such
wenzelm@5127
    70
variables.  If this splitting is not appropriate, use delSWrapper
wenzelm@5127
    71
"split_all_tac".
wenzelm@5127
    72
wenzelm@5127
    73
* HOL/Simplifier:
wenzelm@5127
    74
wenzelm@5127
    75
 - Rewrite rules for case distinctions can now be added permanently to
wenzelm@5127
    76
   the default simpset using Addsplits just like Addsimps. They can be
wenzelm@5127
    77
   removed via Delsplits just like Delsimps. Lower-case versions are
wenzelm@5127
    78
   also available.
wenzelm@5127
    79
wenzelm@5127
    80
 - The rule split_if is now part of the default simpset. This means
wenzelm@5127
    81
   that the simplifier will eliminate all occurrences of if-then-else
wenzelm@5127
    82
   in the conclusion of a goal. To prevent this, you can either remove
wenzelm@5127
    83
   split_if completely from the default simpset by `Delsplits
wenzelm@5127
    84
   [split_if]' or remove it in a specific call of the simplifier using
wenzelm@5127
    85
   `... delsplits [split_if]'.  You can also add/delete other case
wenzelm@5127
    86
   splitting rules to/from the default simpset: every datatype
wenzelm@5127
    87
   generates suitable rules `split_t_case' and `split_t_case_asm'
wenzelm@5127
    88
   (where t is the name of the datatype).
wenzelm@5127
    89
wenzelm@5127
    90
* Classical reasoner - Simplifier combination: new force_tac (and
wenzelm@5127
    91
derivatives Force_tac, force) combines rewriting and classical
wenzelm@5127
    92
reasoning (and whatever other tools) similarly to auto_tac, but is
wenzelm@5127
    93
aimed to solve the given subgoal completely;
wenzelm@5127
    94
wenzelm@5127
    95
wenzelm@5127
    96
*** General ***
wenzelm@5127
    97
wenzelm@5217
    98
* new top-level commands `Goal' and `Goalw' that improve upon `goal'
wenzelm@5127
    99
and `goalw': the theory is no longer needed as an explicit argument -
wenzelm@5127
   100
the current theory context is used; assumptions are no longer returned
wenzelm@5127
   101
at the ML-level unless one of them starts with ==> or !!; it is
wenzelm@5217
   102
recommended to convert to these new commands using isatool fixgoal
wenzelm@5217
   103
(backup your sources first!);
wenzelm@4842
   104
wenzelm@5217
   105
* new top-level commands 'thm' and 'thms' for retrieving theorems from
wenzelm@5207
   106
the current theory context, and 'theory' to lookup stored theories;
paulson@4806
   107
wenzelm@5127
   108
* new theory section 'nonterminals' for purely syntactic types;
wenzelm@4858
   109
wenzelm@5127
   110
* new theory section 'setup' for generic ML setup functions
wenzelm@5127
   111
(e.g. package initialization);
wenzelm@4869
   112
wenzelm@5131
   113
* the distribution now includes Isabelle icons: see
wenzelm@5131
   114
lib/logo/isabelle-{small,tiny}.xpm;
wenzelm@5131
   115
wenzelm@5363
   116
* isatool install - install binaries with absolute references to
wenzelm@5363
   117
ISABELLE_HOME/bin;
wenzelm@5363
   118
wenzelm@5572
   119
* isatool logo -- create instances of the Isabelle logo (as EPS);
wenzelm@5572
   120
wenzelm@5407
   121
* print mode 'emacs' reserved for Isamode;
wenzelm@5407
   122
wenzelm@4711
   123
paulson@4661
   124
*** HOL ***
paulson@4661
   125
wenzelm@5217
   126
* HOL/inductive package reorganized and improved: now supports mutual
paulson@5267
   127
definitions such as
wenzelm@5217
   128
wenzelm@5217
   129
  inductive EVEN ODD
wenzelm@5217
   130
    intrs
wenzelm@5217
   131
      null "0 : EVEN"
wenzelm@5217
   132
      oddI "n : EVEN ==> Suc n : ODD"
wenzelm@5217
   133
      evenI "n : ODD ==> Suc n : EVEN"
wenzelm@5217
   134
wenzelm@5217
   135
new theorem list "elims" contains an elimination rule for each of the
wenzelm@5217
   136
recursive sets; inductive definitions now handle disjunctive premises
wenzelm@5217
   137
correctly (also ZF);
berghofe@5214
   138
wenzelm@5217
   139
INCOMPATIBILITIES: requires Inductive as an ancestor; component
wenzelm@5217
   140
"mutual_induct" no longer exists - the induction rule is always
wenzelm@5217
   141
contained in "induct";
wenzelm@5217
   142
wenzelm@5217
   143
wenzelm@5217
   144
* HOL/datatype package re-implemented and greatly improved: now
paulson@5267
   145
supports mutually recursive datatypes such as
wenzelm@5217
   146
wenzelm@5217
   147
  datatype
wenzelm@5217
   148
    'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
wenzelm@5217
   149
            | SUM ('a aexp) ('a aexp)
wenzelm@5217
   150
            | DIFF ('a aexp) ('a aexp)
wenzelm@5217
   151
            | NUM 'a
wenzelm@5217
   152
  and
wenzelm@5217
   153
    'a bexp = LESS ('a aexp) ('a aexp)
wenzelm@5217
   154
            | AND ('a bexp) ('a bexp)
wenzelm@5217
   155
            | OR ('a bexp) ('a bexp)
wenzelm@5217
   156
paulson@5267
   157
as well as indirectly recursive datatypes such as
berghofe@5214
   158
wenzelm@5217
   159
  datatype
wenzelm@5217
   160
    ('a, 'b) term = Var 'a
wenzelm@5217
   161
                  | App 'b ((('a, 'b) term) list)
berghofe@5214
   162
wenzelm@5217
   163
The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
wenzelm@5217
   164
induction on mutually / indirectly recursive datatypes.
wenzelm@5217
   165
wenzelm@5217
   166
Primrec equations are now stored in theory and can be accessed via
wenzelm@5217
   167
<function_name>.simps.
wenzelm@5217
   168
wenzelm@5217
   169
INCOMPATIBILITIES:
berghofe@5214
   170
wenzelm@5217
   171
  - Theories using datatypes must now have theory Datatype as an
wenzelm@5217
   172
    ancestor.
wenzelm@5217
   173
  - The specific <typename>.induct_tac no longer exists - use the
wenzelm@5217
   174
    generic induct_tac instead.
berghofe@5226
   175
  - natE has been renamed to nat.exhaust - use exhaust_tac
wenzelm@5217
   176
    instead of res_inst_tac ... natE. Note that the variable
berghofe@5226
   177
    names in nat.exhaust differ from the names in natE, this
wenzelm@5217
   178
    may cause some "fragile" proofs to fail.
wenzelm@5217
   179
  - The theorems split_<typename>_case and split_<typename>_case_asm
wenzelm@5217
   180
    have been renamed to <typename>.split and <typename>.split_asm.
wenzelm@5217
   181
  - Since default sorts of type variables are now handled correctly,
wenzelm@5217
   182
    some datatype definitions may have to be annotated with explicit
wenzelm@5217
   183
    sort constraints.
wenzelm@5217
   184
  - Primrec definitions no longer require function name and type
wenzelm@5217
   185
    of recursive argument.
berghofe@5214
   186
wenzelm@5217
   187
Consider using isatool fixdatatype to adapt your theories and proof
wenzelm@5217
   188
scripts to the new package (backup your sources first!).
wenzelm@5217
   189
wenzelm@5217
   190
wenzelm@5217
   191
* HOL/record package: now includes concrete syntax for record types,
wenzelm@5217
   192
terms, updates; still lacks important theorems, like surjective
wenzelm@5217
   193
pairing and split;
berghofe@5214
   194
wenzelm@5125
   195
* reorganized the main HOL image: HOL/Integ and String loaded by
wenzelm@5125
   196
default; theory Main includes everything;
wenzelm@5125
   197
paulson@5650
   198
* automatic simplification of integer sums and comparisons, using cancellation;
paulson@5650
   199
oheimb@5526
   200
* added option_map_eq_Some and not_Some_eq to the default simpset and claset;
wenzelm@5127
   201
wenzelm@5127
   202
* added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
wenzelm@5127
   203
wenzelm@5127
   204
* many new identities for unions, intersections, set difference, etc.;
wenzelm@5127
   205
wenzelm@5127
   206
* expand_if, expand_split, expand_sum_case and expand_nat_case are now
wenzelm@5127
   207
called split_if, split_split, split_sum_case and split_nat_case (to go
wenzelm@5127
   208
with add/delsplits);
wenzelm@5125
   209
wenzelm@5127
   210
* HOL/Prod introduces simplification procedure unit_eq_proc rewriting
wenzelm@5127
   211
(?x::unit) = (); this is made part of the default simpset, which COULD
wenzelm@5127
   212
MAKE EXISTING PROOFS FAIL under rare circumstances (consider
wenzelm@5207
   213
'Delsimprocs [unit_eq_proc];' as last resort); also note that
wenzelm@5207
   214
unit_abs_eta_conv is added in order to counter the effect of
wenzelm@5207
   215
unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
wenzelm@5207
   216
%u.f();
wenzelm@5125
   217
wenzelm@5217
   218
* HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
wenzelm@5217
   219
makes more sense);
berghofe@5109
   220
paulson@5475
   221
* HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
paulson@5475
   222
  It and 'sym RS equals0D' are now in the default  claset, giving automatic
paulson@5475
   223
  disjointness reasoning but breaking a few old proofs.
paulson@5267
   224
wenzelm@5217
   225
* HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
wenzelm@5217
   226
to 'converse' from 'inverse' (for compatibility with ZF and some
wenzelm@5217
   227
literature);
wenzelm@5085
   228
wenzelm@5127
   229
* HOL/recdef can now declare non-recursive functions, with {} supplied as
wenzelm@5127
   230
the well-founded relation;
oheimb@4838
   231
paulson@5490
   232
* HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
paulson@5490
   233
    Compl A.  The "Compl" syntax remains available as input syntax for this
paulson@5490
   234
    release ONLY.
paulson@5490
   235
wenzelm@5127
   236
* HOL/Update: new theory of function updates:
wenzelm@5127
   237
    f(a:=b) == %x. if x=a then b else f x
wenzelm@5127
   238
may also be iterated as in f(a:=b,c:=d,...);
nipkow@5077
   239
wenzelm@5127
   240
* HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
paulson@4899
   241
nipkow@5282
   242
* HOL/List:
nipkow@5282
   243
  - new function list_update written xs[i:=v] that updates the i-th
nipkow@5282
   244
    list position. May also be iterated as in xs[i:=a,j:=b,...].
nipkow@5428
   245
  - new function `upt' written [i..j(] which generates the list
nipkow@5428
   246
    [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
nipkow@5428
   247
    bound write [i..j], which is a shorthand for [i..j+1(].
nipkow@5282
   248
  - new lexicographic orderings and corresponding wellfoundedness theorems.
paulson@4779
   249
wenzelm@5127
   250
* HOL/Arith:
wenzelm@5127
   251
  - removed 'pred' (predecessor) function;
wenzelm@5127
   252
  - generalized some theorems about n-1;
wenzelm@5127
   253
  - many new laws about "div" and "mod";
wenzelm@5127
   254
  - new laws about greatest common divisors (see theory ex/Primes);
oheimb@4766
   255
wenzelm@5127
   256
* HOL/Relation: renamed the relational operator r^-1 "converse"
wenzelm@4842
   257
instead of "inverse";
wenzelm@4711
   258
nipkow@5651
   259
* HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
nipkow@5651
   260
  of the multiset ordering;
nipkow@5651
   261
wenzelm@5127
   262
* directory HOL/Real: a construction of the reals using Dedekind cuts
nipkow@5651
   263
  (not included by default);
nipkow@4835
   264
wenzelm@5127
   265
* directory HOL/UNITY: Chandy and Misra's UNITY formalism;
wenzelm@4711
   266
nipkow@5651
   267
* directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
nipkow@5651
   268
  programs, i.e. different program variables may have different types.
nipkow@5651
   269
paulson@5142
   270
* calling (stac rew i) now fails if "rew" has no effect on the goal
paulson@5142
   271
  [previously, this check worked only if the rewrite rule was unconditional]
paulson@5308
   272
  Now rew can involve either definitions or equalities (either == or =).
wenzelm@5002
   273
wenzelm@5363
   274
paulson@4879
   275
*** ZF ***
paulson@4879
   276
paulson@5332
   277
* theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
paulson@5332
   278
  only the theorems proved on ZF.ML;
paulson@5160
   279
paulson@5475
   280
* ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
paulson@5475
   281
  It and 'sym RS equals0D' are now in the default  claset, giving automatic
paulson@5475
   282
  disjointness reasoning but breaking a few old proofs.
paulson@5267
   283
paulson@5160
   284
* ZF/Update: new theory of function updates
paulson@5160
   285
    with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
paulson@5160
   286
  may also be iterated as in f(a:=b,c:=d,...);
paulson@5160
   287
paulson@4879
   288
* in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
oheimb@4649
   289
paulson@5142
   290
* calling (stac rew i) now fails if "rew" has no effect on the goal
paulson@5142
   291
  [previously, this check worked only if the rewrite rule was unconditional]
paulson@5308
   292
  Now rew can involve either definitions or equalities (either == or =).
paulson@5142
   293
paulson@5160
   294
* case_tac provided for compatibility with HOL
paulson@5160
   295
    (like the old excluded_middle_tac, but with subgoals swapped)
paulson@5160
   296
wenzelm@4842
   297
wenzelm@5127
   298
*** Internal programming interfaces ***
wenzelm@5002
   299
wenzelm@5251
   300
* Pure: several new basic modules made available for general use, see
wenzelm@5251
   301
also src/Pure/README;
wenzelm@5207
   302
wenzelm@5008
   303
* improved the theory data mechanism to support encapsulation (data
wenzelm@5008
   304
kind name replaced by private Object.kind, acting as authorization
wenzelm@5373
   305
key); new type-safe user interface via functor TheoryDataFun; generic
wenzelm@5373
   306
print_data function becomes basically useless;
wenzelm@5002
   307
wenzelm@5251
   308
* removed global_names compatibility flag -- all theory declarations
wenzelm@5251
   309
are qualified by default;
wenzelm@5251
   310
wenzelm@5085
   311
* module Pure/Syntax now offers quote / antiquote translation
wenzelm@5085
   312
functions (useful for Hoare logic etc. with implicit dependencies);
wenzelm@5373
   313
see HOL/ex/Antiquote for an example use;
wenzelm@5085
   314
wenzelm@5127
   315
* Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
wenzelm@5127
   316
cterm -> thm;
wenzelm@5127
   317
wenzelm@5207
   318
* new tactical CHANGED_GOAL for checking that a tactic modifies a
wenzelm@5207
   319
subgoal;
paulson@5142
   320
wenzelm@5251
   321
* Display.print_goals function moved to Locale.print_goals;
wenzelm@5251
   322
wenzelm@5002
   323
wenzelm@5002
   324
wenzelm@4410
   325
New in Isabelle98 (January 1998)
wenzelm@4410
   326
--------------------------------
wenzelm@4410
   327
wenzelm@4410
   328
*** Overview of INCOMPATIBILITIES (see below for more details) ***
wenzelm@4410
   329
wenzelm@4410
   330
* changed lexical syntax of terms / types: dots made part of long
wenzelm@4410
   331
identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
wenzelm@4410
   332
wenzelm@4410
   333
* simpset (and claset) reference variable replaced by functions
wenzelm@4410
   334
simpset / simpset_ref;
wenzelm@4410
   335
wenzelm@4410
   336
* no longer supports theory aliases (via merge) and non-trivial
wenzelm@4410
   337
implicit merge of thms' signatures;
wenzelm@4410
   338
wenzelm@4410
   339
* most internal names of constants changed due to qualified names;
wenzelm@4410
   340
wenzelm@4410
   341
* changed Pure/Sequence interface (see Pure/seq.ML);
wenzelm@4410
   342
wenzelm@3454
   343
paulson@3715
   344
*** General Changes ***
paulson@3715
   345
wenzelm@4174
   346
* hierachically structured name spaces (for consts, types, axms, thms
wenzelm@3943
   347
etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
wenzelm@4108
   348
old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
wenzelm@4108
   349
isatool fixdots ensures space after dots (e.g. "%x. x"); set
wenzelm@4174
   350
long_names for fully qualified output names; NOTE: ML programs
wenzelm@4174
   351
(special tactics, packages etc.) referring to internal names may have
wenzelm@4174
   352
to be adapted to cope with fully qualified names; in case of severe
wenzelm@4174
   353
backward campatibility problems try setting 'global_names' at compile
wenzelm@4174
   354
time to have enrything declared within a flat name space; one may also
wenzelm@4174
   355
fine tune name declarations in theories via the 'global' and 'local'
wenzelm@4174
   356
section;
wenzelm@4108
   357
wenzelm@4108
   358
* reimplemented the implicit simpset and claset using the new anytype
wenzelm@4108
   359
data filed in signatures; references simpset:simpset ref etc. are
wenzelm@4108
   360
replaced by functions simpset:unit->simpset and
wenzelm@4108
   361
simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
wenzelm@4108
   362
to patch your ML files accordingly;
paulson@3856
   363
wenzelm@3857
   364
* HTML output now includes theory graph data for display with Java
wenzelm@3857
   365
applet or isatool browser; data generated automatically via isatool
wenzelm@3901
   366
usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
wenzelm@3857
   367
paulson@3856
   368
* defs may now be conditional; improved rewrite_goals_tac to handle
paulson@3856
   369
conditional equations;
paulson@3856
   370
wenzelm@4174
   371
* defs now admits additional type arguments, using TYPE('a) syntax;
wenzelm@4174
   372
wenzelm@3901
   373
* theory aliases via merge (e.g. M=A+B+C) no longer supported, always
wenzelm@3901
   374
creates a new theory node; implicit merge of thms' signatures is
wenzelm@4112
   375
restricted to 'trivial' ones; COMPATIBILITY: one may have to use
wenzelm@3901
   376
transfer:theory->thm->thm in (rare) cases;
wenzelm@3901
   377
wenzelm@3968
   378
* improved handling of draft signatures / theories; draft thms (and
wenzelm@3968
   379
ctyps, cterms) are automatically promoted to real ones;
wenzelm@3968
   380
wenzelm@3901
   381
* slightly changed interfaces for oracles: admit many per theory, named
wenzelm@3901
   382
(e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
wenzelm@3901
   383
wenzelm@3901
   384
* print_goals: optional output of const types (set show_consts and
wenzelm@3901
   385
show_types);
wenzelm@3851
   386
wenzelm@4388
   387
* improved output of warnings (###) and errors (***);
wenzelm@3697
   388
paulson@4178
   389
* subgoal_tac displays a warning if the new subgoal has type variables;
paulson@4178
   390
paulson@3715
   391
* removed old README and Makefiles;
wenzelm@3697
   392
paulson@3856
   393
* replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
wenzelm@3670
   394
paulson@3715
   395
* removed obsolete init_pps and init_database;
paulson@3715
   396
paulson@3715
   397
* deleted the obsolete tactical STATE, which was declared by
paulson@3715
   398
    fun STATE tacfun st = tacfun st st;
paulson@3715
   399
wenzelm@4388
   400
* cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
wenzelm@4388
   401
(which abbreviates $HOME);
wenzelm@4269
   402
wenzelm@4269
   403
* changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
wenzelm@4269
   404
use isatool fixseq to adapt your ML programs (this works for fully
wenzelm@4269
   405
qualified references to the Sequence structure only!);
wenzelm@4269
   406
wenzelm@4381
   407
* use_thy no longer requires writable current directory; it always
wenzelm@4381
   408
reloads .ML *and* .thy file, if either one is out of date;
wenzelm@4269
   409
paulson@3715
   410
paulson@3715
   411
*** Classical Reasoner ***
paulson@3715
   412
wenzelm@3744
   413
* Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
wenzelm@3744
   414
tactics that use classical reasoning to simplify a subgoal without
wenzelm@3744
   415
splitting it into several subgoals;
paulson@3715
   416
paulson@3719
   417
* Safe_tac: like safe_tac but uses the default claset;
paulson@3719
   418
paulson@3715
   419
paulson@3715
   420
*** Simplifier ***
paulson@3715
   421
paulson@3715
   422
* added simplification meta rules:
paulson@3715
   423
    (asm_)(full_)simplify: simpset -> thm -> thm;
paulson@3715
   424
paulson@3715
   425
* simplifier.ML no longer part of Pure -- has to be loaded by object
paulson@3715
   426
logics (again);
paulson@3715
   427
paulson@3715
   428
* added prems argument to simplification procedures;
paulson@3715
   429
paulson@4325
   430
* HOL, FOL, ZF: added infix function `addsplits':
paulson@4325
   431
  instead of `<simpset> setloop (split_tac <thms>)'
paulson@4325
   432
  you can simply write `<simpset> addsplits <thms>'
paulson@4325
   433
paulson@3715
   434
paulson@3715
   435
*** Syntax ***
paulson@3715
   436
wenzelm@4174
   437
* TYPE('a) syntax for type reflection terms;
wenzelm@4174
   438
wenzelm@3985
   439
* no longer handles consts with name "" -- declare as 'syntax' instead;
paulson@3856
   440
paulson@3856
   441
* pretty printer: changed order of mixfix annotation preference (again!);
wenzelm@3846
   442
paulson@3715
   443
* Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
paulson@3715
   444
paulson@3715
   445
paulson@3715
   446
*** HOL ***
paulson@3715
   447
oheimb@4207
   448
* HOL: there is a new splitter `split_asm_tac' that can be used e.g. 
oheimb@4189
   449
  with `addloop' of the simplifier to faciliate case splitting in premises.
oheimb@4189
   450
nipkow@4035
   451
* HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
wenzelm@3985
   452
wenzelm@3985
   453
* HOL/Auth: new protocol proofs including some for the Internet
nipkow@4035
   454
  protocol TLS;
wenzelm@3985
   455
wenzelm@4125
   456
* HOL/Map: new theory of `maps' a la VDM;
nipkow@3982
   457
wenzelm@4335
   458
* HOL/simplifier: simplification procedures nat_cancel_sums for
wenzelm@4335
   459
cancelling out common nat summands from =, <, <= (in)equalities, or
wenzelm@4335
   460
differences; simplification procedures nat_cancel_factor for
wenzelm@4335
   461
cancelling common factor from =, <, <= (in)equalities over natural
wenzelm@4373
   462
sums; nat_cancel contains both kinds of procedures, it is installed by
wenzelm@4373
   463
default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
wenzelm@4335
   464
nipkow@3580
   465
* HOL/simplifier: terms of the form
paulson@4325
   466
  `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
nipkow@3580
   467
  are rewritten to
nipkow@4035
   468
  `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
nipkow@4035
   469
  and those of the form
paulson@4325
   470
  `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
nipkow@4035
   471
  are rewritten to
nipkow@4035
   472
  `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
nipkow@4035
   473
nipkow@4035
   474
* HOL/datatype
nipkow@4035
   475
  Each datatype `t' now comes with a theorem `split_t_case' of the form
nipkow@3580
   476
nipkow@4035
   477
  P(t_case f1 ... fn x) =
nipkow@4035
   478
     ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
nipkow@4035
   479
        ...
oheimb@4189
   480
       (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
nipkow@4035
   481
     )
nipkow@4035
   482
oheimb@4930
   483
  and a theorem `split_t_case_asm' of the form
oheimb@4189
   484
oheimb@4189
   485
  P(t_case f1 ... fn x) =
oheimb@4189
   486
    ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
oheimb@4189
   487
        ...
oheimb@4189
   488
       (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
oheimb@4189
   489
     )
oheimb@4930
   490
  which can be added to a simpset via `addsplits'. The existing theorems
oheimb@4930
   491
  expand_list_case and expand_option_case have been renamed to
oheimb@4930
   492
  split_list_case and split_option_case.
oheimb@4189
   493
nipkow@4361
   494
* HOL/Arithmetic:
nipkow@4361
   495
  - `pred n' is automatically converted to `n-1'.
nipkow@4361
   496
    Users are strongly encouraged not to use `pred' any longer,
nipkow@4361
   497
    because it will disappear altogether at some point.
nipkow@4361
   498
  - Users are strongly encouraged to write "0 < n" rather than
nipkow@4361
   499
    "n ~= 0". Theorems and proof tools have been modified towards this
nipkow@4361
   500
    `standard'.
nipkow@4357
   501
nipkow@4502
   502
* HOL/Lists:
nipkow@4502
   503
  the function "set_of_list" has been renamed "set" (and its theorems too);
nipkow@4502
   504
  the function "nth" now takes its arguments in the reverse order and
nipkow@4502
   505
  has acquired the infix notation "!" as in "xs!n".
paulson@3570
   506
paulson@4154
   507
* HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
paulson@4154
   508
paulson@4154
   509
* HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
paulson@4154
   510
  specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
paulson@4154
   511
wenzelm@4575
   512
* HOL/record: extensible records with schematic structural subtyping
wenzelm@4575
   513
(single inheritance); EXPERIMENTAL version demonstrating the encoding,
wenzelm@4575
   514
still lacks various theorems and concrete record syntax;
wenzelm@4575
   515
wenzelm@4125
   516
paulson@3715
   517
*** HOLCF ***
wenzelm@3535
   518
wenzelm@4125
   519
* removed "axioms" and "generated by" sections;
wenzelm@4125
   520
oheimb@4123
   521
* replaced "ops" section by extended "consts" section, which is capable of
wenzelm@4125
   522
  handling the continuous function space "->" directly;
wenzelm@4125
   523
wenzelm@4125
   524
* domain package:
wenzelm@4125
   525
  . proves theorems immediately and stores them in the theory,
wenzelm@4125
   526
  . creates hierachical name space,
wenzelm@4125
   527
  . now uses normal mixfix annotations (instead of cinfix...),
wenzelm@4125
   528
  . minor changes to some names and values (for consistency),
wenzelm@4125
   529
  . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
wenzelm@4125
   530
  . separator between mutual domain defs: changed "," to "and",
wenzelm@4125
   531
  . improved handling of sort constraints;  now they have to
wenzelm@4125
   532
    appear on the left-hand side of the equations only;
oheimb@4123
   533
oheimb@4123
   534
* fixed LAM <x,y,zs>.b syntax;
wenzelm@3567
   535
wenzelm@3744
   536
* added extended adm_tac to simplifier in HOLCF -- can now discharge
wenzelm@3744
   537
adm (%x. P (t x)), where P is chainfinite and t continuous;
wenzelm@3579
   538
wenzelm@3579
   539
paulson@3719
   540
*** FOL and ZF ***
paulson@3719
   541
oheimb@4207
   542
* FOL: there is a new splitter `split_asm_tac' that can be used e.g. 
oheimb@4189
   543
  with `addloop' of the simplifier to faciliate case splitting in premises.
oheimb@4189
   544
wenzelm@3744
   545
* qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
wenzelm@3744
   546
in HOL, they strip ALL and --> from proved theorems;
wenzelm@3744
   547
paulson@3719
   548
wenzelm@3579
   549
wenzelm@3006
   550
New in Isabelle94-8 (May 1997)
wenzelm@3006
   551
------------------------------
wenzelm@2654
   552
paulson@3002
   553
*** General Changes ***
paulson@3002
   554
paulson@3002
   555
* new utilities to build / run / maintain Isabelle etc. (in parts
paulson@3002
   556
still somewhat experimental); old Makefiles etc. still functional;
wenzelm@2971
   557
wenzelm@3205
   558
* new 'Isabelle System Manual';
wenzelm@3205
   559
wenzelm@2825
   560
* INSTALL text, together with ./configure and ./build scripts;
wenzelm@2773
   561
wenzelm@3006
   562
* reimplemented type inference for greater efficiency, better error
wenzelm@3006
   563
messages and clean internal interface;
paulson@3002
   564
paulson@3002
   565
* prlim command for dealing with lots of subgoals (an easier way of
paulson@3002
   566
setting goals_limit);
paulson@3002
   567
wenzelm@3006
   568
wenzelm@3006
   569
*** Syntax ***
paulson@3002
   570
wenzelm@3116
   571
* supports alternative (named) syntax tables (parser and pretty
wenzelm@3116
   572
printer); internal interface is provided by add_modesyntax(_i);
wenzelm@3116
   573
paulson@3002
   574
* Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
paulson@3002
   575
be used in conjunction with the Isabelle symbol font; uses the
paulson@3002
   576
"symbols" syntax table;
paulson@3002
   577
wenzelm@2705
   578
* added token_translation interface (may translate name tokens in
wenzelm@2756
   579
arbitrary ways, dependent on their type (free, bound, tfree, ...) and
wenzelm@3116
   580
the current print_mode); IMPORTANT: user print translation functions
wenzelm@3116
   581
are responsible for marking newly introduced bounds
wenzelm@3116
   582
(Syntax.mark_boundT);
wenzelm@2705
   583
wenzelm@2730
   584
* token translations for modes "xterm" and "xterm_color" that display
wenzelm@3006
   585
names in bold, underline etc. or colors (which requires a color
wenzelm@3006
   586
version of xterm);
wenzelm@2730
   587
paulson@3002
   588
* infixes may now be declared with names independent of their syntax;
paulson@3002
   589
paulson@3002
   590
* added typed_print_translation (like print_translation, but may
paulson@3002
   591
access type of constant);
paulson@3002
   592
wenzelm@3006
   593
paulson@3002
   594
*** Classical Reasoner ***
paulson@3002
   595
paulson@3002
   596
Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
paulson@3002
   597
some limitations.  Blast_tac...
paulson@3002
   598
  + ignores addss, addbefore, addafter; this restriction is intrinsic
paulson@3002
   599
  + ignores elimination rules that don't have the correct format
paulson@3002
   600
	(the conclusion MUST be a formula variable)
paulson@3002
   601
  + ignores types, which can make HOL proofs fail
paulson@3002
   602
  + rules must not require higher-order unification, e.g. apply_type in ZF
paulson@3002
   603
    [message "Function Var's argument not a bound variable" relates to this]
paulson@3002
   604
  + its proof strategy is more general but can actually be slower
paulson@3002
   605
wenzelm@3107
   606
* substitution with equality assumptions no longer permutes other
wenzelm@3107
   607
assumptions;
paulson@3002
   608
paulson@3002
   609
* minor changes in semantics of addafter (now called addaltern); renamed
paulson@3002
   610
setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
wenzelm@3107
   611
(and access functions for it);
paulson@3002
   612
oheimb@3317
   613
* improved combination of classical reasoner and simplifier: 
oheimb@3317
   614
  + functions for handling clasimpsets
oheimb@3317
   615
  + improvement of addss: now the simplifier is called _after_ the
oheimb@3317
   616
    safe steps.
oheimb@3317
   617
  + safe variant of addss called addSss: uses safe simplifications
oheimb@3317
   618
    _during_ the safe steps. It is more complete as it allows multiple 
oheimb@3317
   619
    instantiations of unknowns (e.g. with slow_tac).
wenzelm@3006
   620
paulson@3002
   621
*** Simplifier ***
paulson@3002
   622
wenzelm@3006
   623
* added interface for simplification procedures (functions that
wenzelm@3006
   624
produce *proven* rewrite rules on the fly, depending on current
wenzelm@3006
   625
redex);
wenzelm@3006
   626
wenzelm@3006
   627
* ordering on terms as parameter (used for ordered rewriting);
wenzelm@3006
   628
wenzelm@3107
   629
* new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
paulson@3002
   630
paulson@3002
   631
* the solver is now split into a safe and an unsafe part.
paulson@3002
   632
This should be invisible for the normal user, except that the
paulson@3002
   633
functions setsolver and addsolver have been renamed to setSolver and
wenzelm@3107
   634
addSolver; added safe_asm_full_simp_tac;
paulson@3002
   635
paulson@3002
   636
paulson@3002
   637
*** HOL ***
paulson@3002
   638
nipkow@3042
   639
* a generic induction tactic `induct_tac' which works for all datatypes and
wenzelm@3107
   640
also for type `nat';
nipkow@3042
   641
nipkow@3316
   642
* a generic case distinction tactic `exhaust_tac' which works for all
nipkow@3316
   643
datatypes and also for type `nat';
nipkow@3316
   644
nipkow@3316
   645
* each datatype comes with a function `size';
nipkow@3316
   646
paulson@3002
   647
* patterns in case expressions allow tuple patterns as arguments to
wenzelm@3107
   648
constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
paulson@3002
   649
paulson@3002
   650
* primrec now also works with type nat;
paulson@3002
   651
paulson@3338
   652
* recdef: a new declaration form, allows general recursive functions to be
paulson@3338
   653
defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
paulson@3338
   654
paulson@3002
   655
* the constant for negation has been renamed from "not" to "Not" to
wenzelm@3107
   656
harmonize with FOL, ZF, LK, etc.;
paulson@3002
   657
wenzelm@3107
   658
* HOL/ex/LFilter theory of a corecursive "filter" functional for
wenzelm@3107
   659
infinite lists;
paulson@3002
   660
wenzelm@3227
   661
* HOL/Modelcheck demonstrates invocation of model checker oracle;
wenzelm@3227
   662
paulson@3002
   663
* HOL/ex/Ring.thy declares cring_simp, which solves equational
paulson@3002
   664
problems in commutative rings, using axiomatic type classes for + and *;
paulson@3002
   665
paulson@3002
   666
* more examples in HOL/MiniML and HOL/Auth;
paulson@3002
   667
paulson@3002
   668
* more default rewrite rules for quantifiers, union/intersection;
paulson@3002
   669
nipkow@3321
   670
* a new constant `arbitrary == @x.False';
nipkow@3321
   671
wenzelm@3107
   672
* HOLCF/IOA replaces old HOL/IOA;
wenzelm@3107
   673
slotosch@2653
   674
* HOLCF changes: derived all rules and arities 
slotosch@2653
   675
  + axiomatic type classes instead of classes 
slotosch@2653
   676
  + typedef instead of faking type definitions
paulson@2747
   677
  + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
wenzelm@2730
   678
  + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
slotosch@2653
   679
  + eliminated the types void, one, tr
slotosch@2653
   680
  + use unit lift and bool lift (with translations) instead of one and tr
slotosch@2653
   681
  + eliminated blift from Lift3.thy (use Def instead of blift)
wenzelm@3107
   682
  all eliminated rules are derived as theorems --> no visible changes ;
oheimb@2649
   683
wenzelm@3006
   684
paulson@3002
   685
*** ZF ***
wenzelm@2553
   686
paulson@2865
   687
* ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
paulson@2865
   688
rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
paulson@2865
   689
as ZF_cs addSIs [equalityI];
wenzelm@2553
   690
wenzelm@2554
   691
wenzelm@2732
   692
wenzelm@2553
   693
New in Isabelle94-7 (November 96)
wenzelm@2553
   694
---------------------------------
wenzelm@2553
   695
wenzelm@2553
   696
* allowing negative levels (as offsets) in prlev and choplev;
wenzelm@2553
   697
wenzelm@2554
   698
* super-linear speedup for large simplifications;
wenzelm@2554
   699
wenzelm@2554
   700
* FOL, ZF and HOL now use miniscoping: rewriting pushes
wenzelm@2554
   701
quantifications in as far as possible (COULD MAKE EXISTING PROOFS
wenzelm@2554
   702
FAIL); can suppress it using the command Delsimps (ex_simps @
wenzelm@2554
   703
all_simps); De Morgan laws are also now included, by default;
wenzelm@2554
   704
wenzelm@2554
   705
* improved printing of ==>  :  ~:
wenzelm@2554
   706
wenzelm@2554
   707
* new object-logic "Sequents" adds linear logic, while replacing LK
wenzelm@2554
   708
and Modal (thanks to Sara Kalvala);
wenzelm@2554
   709
wenzelm@2554
   710
* HOL/Auth: correctness proofs for authentication protocols;
wenzelm@2554
   711
wenzelm@2554
   712
* HOL: new auto_tac combines rewriting and classical reasoning (many
wenzelm@2554
   713
examples on HOL/Auth);
wenzelm@2554
   714
wenzelm@2554
   715
* HOL: new command AddIffs for declaring theorems of the form P=Q to
wenzelm@2554
   716
the rewriter and classical reasoner simultaneously;
wenzelm@2554
   717
wenzelm@2554
   718
* function uresult no longer returns theorems in "standard" format;
wenzelm@2554
   719
regain previous version by: val uresult = standard o uresult;
wenzelm@2554
   720
wenzelm@2554
   721
wenzelm@2554
   722
wenzelm@2554
   723
New in Isabelle94-6
wenzelm@2554
   724
-------------------
wenzelm@2554
   725
wenzelm@2554
   726
* oracles -- these establish an interface between Isabelle and trusted
wenzelm@2554
   727
external reasoners, which may deliver results as theorems;
wenzelm@2554
   728
wenzelm@2554
   729
* proof objects (in particular record all uses of oracles);
wenzelm@2554
   730
wenzelm@2554
   731
* Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
wenzelm@2554
   732
wenzelm@2554
   733
* "constdefs" section in theory files;
wenzelm@2554
   734
wenzelm@2554
   735
* "primrec" section (HOL) no longer requires names;
wenzelm@2554
   736
wenzelm@2554
   737
* internal type "tactic" now simply "thm -> thm Sequence.seq";
wenzelm@2554
   738
wenzelm@2554
   739
wenzelm@2554
   740
wenzelm@2554
   741
New in Isabelle94-5
wenzelm@2554
   742
-------------------
wenzelm@2554
   743
wenzelm@2554
   744
* reduced space requirements;
wenzelm@2554
   745
wenzelm@2554
   746
* automatic HTML generation from theories;
wenzelm@2554
   747
wenzelm@2554
   748
* theory files no longer require "..." (quotes) around most types;
wenzelm@2554
   749
wenzelm@2554
   750
* new examples, including two proofs of the Church-Rosser theorem;
wenzelm@2554
   751
wenzelm@2554
   752
* non-curried (1994) version of HOL is no longer distributed;
wenzelm@2554
   753
wenzelm@2553
   754
paulson@2557
   755
paulson@2557
   756
New in Isabelle94-4
paulson@2557
   757
-------------------
paulson@2557
   758
paulson@2747
   759
* greatly reduced space requirements;
paulson@2557
   760
paulson@2557
   761
* theory files (.thy) no longer require \...\ escapes at line breaks;
paulson@2557
   762
paulson@2557
   763
* searchable theorem database (see the section "Retrieving theorems" on 
paulson@2557
   764
page 8 of the Reference Manual);
paulson@2557
   765
paulson@2557
   766
* new examples, including Grabczewski's monumental case study of the
paulson@2557
   767
Axiom of Choice;
paulson@2557
   768
paulson@2557
   769
* The previous version of HOL renamed to Old_HOL;
paulson@2557
   770
paulson@2557
   771
* The new version of HOL (previously called CHOL) uses a curried syntax 
paulson@2557
   772
for functions.  Application looks like f a b instead of f(a,b);
paulson@2557
   773
paulson@2557
   774
* Mutually recursive inductive definitions finally work in HOL;
paulson@2557
   775
paulson@2557
   776
* In ZF, pattern-matching on tuples is now available in all abstractions and
paulson@2557
   777
translates to the operator "split";
paulson@2557
   778
paulson@2557
   779
paulson@2557
   780
paulson@2557
   781
New in Isabelle94-3
paulson@2557
   782
-------------------
paulson@2557
   783
paulson@2557
   784
* new infix operator, addss, allowing the classical reasoner to 
paulson@2557
   785
perform simplification at each step of its search.  Example:
paulson@2557
   786
	fast_tac (cs addss ss)
paulson@2557
   787
paulson@2557
   788
* a new logic, CHOL, the same as HOL, but with a curried syntax 
paulson@2557
   789
for functions.  Application looks like f a b instead of f(a,b).  Also pairs 
paulson@2557
   790
look like (a,b) instead of <a,b>;
paulson@2557
   791
paulson@2557
   792
* PLEASE NOTE: CHOL will eventually replace HOL!
paulson@2557
   793
paulson@2557
   794
* In CHOL, pattern-matching on tuples is now available in all abstractions.
paulson@2557
   795
It translates to the operator "split".  A new theory of integers is available;
paulson@2557
   796
paulson@2557
   797
* In ZF, integer numerals now denote two's-complement binary integers.
paulson@2557
   798
Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
paulson@2557
   799
paulson@2557
   800
* Many new examples: I/O automata, Church-Rosser theorem, equivalents 
paulson@2557
   801
of the Axiom of Choice;
paulson@2557
   802
paulson@2557
   803
paulson@2557
   804
paulson@2557
   805
New in Isabelle94-2
paulson@2557
   806
-------------------
paulson@2557
   807
paulson@2557
   808
* Significantly faster resolution;  
paulson@2557
   809
paulson@2557
   810
* the different sections in a .thy file can now be mixed and repeated
paulson@2557
   811
freely;
paulson@2557
   812
paulson@2557
   813
* Database of theorems for FOL, HOL and ZF.  New
paulson@2557
   814
commands including qed, qed_goal and bind_thm store theorems in the database.
paulson@2557
   815
paulson@2557
   816
* Simple database queries: return a named theorem (get_thm) or all theorems of
paulson@2557
   817
a given theory (thms_of), or find out what theory a theorem was proved in
paulson@2557
   818
(theory_of_thm);
paulson@2557
   819
paulson@2557
   820
* Bugs fixed in the inductive definition and datatype packages;
paulson@2557
   821
paulson@2557
   822
* The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
paulson@2557
   823
and HOL_dup_cs obsolete;
paulson@2557
   824
paulson@2557
   825
* Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
paulson@2557
   826
have been removed;
paulson@2557
   827
paulson@2557
   828
* Simpler definition of function space in ZF;
paulson@2557
   829
paulson@2557
   830
* new results about cardinal and ordinal arithmetic in ZF;
paulson@2557
   831
paulson@2557
   832
* 'subtype' facility in HOL for introducing new types as subsets of existing
paulson@2557
   833
types;
paulson@2557
   834
paulson@2557
   835
wenzelm@2553
   836
$Id$