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NEWS

author | wenzelm |

Wed Sep 21 14:46:10 2005 +0200 (2005-09-21 ago) | |

changeset 17562 | 623c9e8668aa |

parent 17548 | 4949ab06913c |

child 17564 | 0350ac95c4b6 |

permissions | -rw-r--r-- |

tuned;

1 Isabelle NEWS -- history user-relevant changes

2 ==============================================

4 New in Isabelle2005 (September 2005)

5 ------------------------------------

7 *** General ***

9 * Theory headers: the new header syntax for Isar theories is

11 theory <name>

12 imports <theory1> ... <theoryN>

13 uses <file1> ... <fileM>

14 begin

16 where the 'uses' part is optional. The previous syntax

18 theory <name> = <theory1> + ... + <theoryN>:

20 will disappear in the next release. Use isatool fixheaders to convert

21 existing theory files. Note that there is no change in ancient

22 non-Isar theories now, but these will disappear soon.

24 * Theory loader: parent theories can now also be referred to via

25 relative and absolute paths.

27 * Command 'find_theorems' searches for a list of criteria instead of a

28 list of constants. Known criteria are: intro, elim, dest, name:string,

29 simp:term, and any term. Criteria can be preceded by '-' to select

30 theorems that do not match. Intro, elim, dest select theorems that

31 match the current goal, name:s selects theorems whose fully qualified

32 name contain s, and simp:term selects all simplification rules whose

33 lhs match term. Any other term is interpreted as pattern and selects

34 all theorems matching the pattern. Available in ProofGeneral under

35 'ProofGeneral -> Find Theorems' or C-c C-f. Example:

37 C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."

39 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",

40 matching the current goal as introduction rule and not having "HOL."

41 in their name (i.e. not being defined in theory HOL).

43 * Command 'thms_containing' has been discontinued in favour of

44 'find_theorems'; INCOMPATIBILITY.

46 * Communication with Proof General is now 8bit clean, which means that

47 Unicode text in UTF-8 encoding may be used within theory texts (both

48 formal and informal parts). Cf. option -U of the Isabelle Proof

49 General interface. Here are some simple examples (cf. src/HOL/ex):

51 http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html

52 http://isabelle.in.tum.de/library/HOL/ex/Chinese.html

54 * Improved efficiency of the Simplifier and, to a lesser degree, the

55 Classical Reasoner. Typical big applications run around 2 times

56 faster.

58 * ProofGeneral interface: the default settings no longer prefer xemacs

59 over GNU emacs. Users typically need to experiment with various

60 variations on PROOFGENERAL_OPTIONS="... -p emacs" to find the most

61 stable Emacs version on their platform.

64 *** Document preparation ***

66 * Commands 'display_drafts' and 'print_drafts' perform simple output

67 of raw sources. Only those symbols that do not require additional

68 LaTeX packages (depending on comments in isabellesym.sty) are

69 displayed properly, everything else is left verbatim. isatool display

70 and isatool print are used as front ends (these are subject to the

71 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).

73 * Command tags control specific markup of certain regions of text,

74 notably folding and hiding. Predefined tags include "theory" (for

75 theory begin and end), "proof" for proof commands, and "ML" for

76 commands involving ML code; the additional tags "visible" and

77 "invisible" are unused by default. Users may give explicit tag

78 specifications in the text, e.g. ''by %invisible (auto)''. The

79 interpretation of tags is determined by the LaTeX job during document

80 preparation: see option -V of isatool usedir, or options -n and -t of

81 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,

82 \isadroptag.

84 Several document versions may be produced at the same time via isatool

85 usedir (the generated index.html will link all of them). Typical

86 specifications include ''-V document=theory,proof,ML'' to present

87 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold

88 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit

89 these parts without any formal replacement text. The Isabelle site

90 default settings produce ''document'' and ''outline'' versions as

91 specified above.

93 * Several new antiquotations:

95 @{term_type term} prints a term with its type annotated;

97 @{typeof term} prints the type of a term;

99 @{const const} is the same as @{term const}, but checks that the

100 argument is a known logical constant;

102 @{term_style style term} and @{thm_style style thm} print a term or

103 theorem applying a "style" to it

105 @{ML text}

107 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of

108 definitions, equations, inequations etc., 'concl' printing only the

109 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'

110 to print the specified premise. TermStyle.add_style provides an ML

111 interface for introducing further styles. See also the "LaTeX Sugar"

112 document practical applications. The ML antiquotation prints

113 type-checked ML expressions verbatim.

115 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',

116 and 'text' support optional locale specification '(in loc)', which

117 specifies the default context for interpreting antiquotations. For

118 example: 'text (in lattice) {* @{thm inf_assoc}*}'.

120 * Option 'locale=NAME' of antiquotations specifies an alternative

121 context interpreting the subsequent argument. For example: @{thm

122 [locale=lattice] inf_assoc}.

124 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within

125 a proof context.

127 * Proper output of antiquotations for theory commands involving a

128 proof context (such as 'locale' or 'theorem (in loc) ...').

130 * Delimiters of outer tokens (string etc.) now produce separate LaTeX

131 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).

133 * isatool usedir: new option -C (default true) controls whether option

134 -D should include a copy of the original document directory; -C false

135 prevents unwanted effects such as copying of administrative CVS data.

138 *** Pure ***

140 * Considerably improved version of 'constdefs' command. Now performs

141 automatic type-inference of declared constants; additional support for

142 local structure declarations (cf. locales and HOL records), see also

143 isar-ref manual. Potential INCOMPATIBILITY: need to observe strictly

144 sequential dependencies of definitions within a single 'constdefs'

145 section; moreover, the declared name needs to be an identifier. If

146 all fails, consider to fall back on 'consts' and 'defs' separately.

148 * Improved indexed syntax and implicit structures. First of all,

149 indexed syntax provides a notational device for subscripted

150 application, using the new syntax \<^bsub>term\<^esub> for arbitrary

151 expressions. Secondly, in a local context with structure

152 declarations, number indexes \<^sub>n or the empty index (default

153 number 1) refer to a certain fixed variable implicitly; option

154 show_structs controls printing of implicit structures. Typical

155 applications of these concepts involve record types and locales.

157 * New command 'no_syntax' removes grammar declarations (and

158 translations) resulting from the given syntax specification, which is

159 interpreted in the same manner as for the 'syntax' command.

161 * 'Advanced' translation functions (parse_translation etc.) may depend

162 on the signature of the theory context being presently used for

163 parsing/printing, see also isar-ref manual.

165 * Improved 'oracle' command provides a type-safe interface to turn an

166 ML expression of type theory -> T -> term into a primitive rule of

167 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle

168 is already included here); see also FOL/ex/IffExample.thy;

169 INCOMPATIBILITY.

171 * axclass: name space prefix for class "c" is now "c_class" (was "c"

172 before); "cI" is no longer bound, use "c.intro" instead.

173 INCOMPATIBILITY. This change avoids clashes of fact bindings for

174 axclasses vs. locales.

176 * Improved internal renaming of symbolic identifiers -- attach primes

177 instead of base 26 numbers.

179 * New flag show_question_marks controls printing of leading question

180 marks in schematic variable names.

182 * In schematic variable names, *any* symbol following \<^isub> or

183 \<^isup> is now treated as part of the base name. For example, the

184 following works without printing of awkward ".0" indexes:

186 lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"

187 by simp

189 * Inner syntax includes (*(*nested*) comments*).

191 * Pretty printer now supports unbreakable blocks, specified in mixfix

192 annotations as "(00...)".

194 * Clear separation of logical types and nonterminals, where the latter

195 may only occur in 'syntax' specifications or type abbreviations.

196 Before that distinction was only partially implemented via type class

197 "logic" vs. "{}". Potential INCOMPATIBILITY in rare cases of improper

198 use of 'types'/'consts' instead of 'nonterminals'/'syntax'. Some very

199 exotic syntax specifications may require further adaption

200 (e.g. Cube/Base.thy).

202 * Removed obsolete type class "logic", use the top sort {} instead.

203 Note that non-logical types should be declared as 'nonterminals'

204 rather than 'types'. INCOMPATIBILITY for new object-logic

205 specifications.

207 * 'defs': more well-formedness checks of overloaded definitions.

209 * Attributes 'induct' and 'cases': type or set names may now be

210 locally fixed variables as well.

212 * Simplifier: can now control the depth to which conditional rewriting

213 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth

214 Limit.

216 * Simplifier: simplification procedures may now take the current

217 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc

218 interface), which is very useful for calling the Simplifier

219 recursively. Minor INCOMPATIBILITY: the 'prems' argument of simprocs

220 is gone -- use prems_of_ss on the simpset instead. Moreover, the

221 low-level mk_simproc no longer applies Logic.varify internally, to

222 allow for use in a context of fixed variables.

224 * thin_tac now works even if the assumption being deleted contains !!

225 or ==>. More generally, erule now works even if the major premise of

226 the elimination rule contains !! or ==>.

228 * Reorganized bootstrapping of the Pure theories; CPure is now derived

229 from Pure, which contains all common declarations already. Both

230 theories are defined via plain Isabelle/Isar .thy files.

231 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /

232 CPure.elim / CPure.dest attributes) now appear in the Pure name space;

233 use isatool fixcpure to adapt your theory and ML sources.

235 * New syntax 'name(i-j, i-, i, ...)' for referring to specific

236 selections of theorems in named facts via index ranges.

238 * 'print_theorems': in theory mode, really print the difference

239 wrt. the last state (works for interactive theory development only),

240 in proof mode print all local facts (cf. 'print_facts');

242 * 'hide': option '(open)' hides only base names.

244 * More efficient treatment of intermediate checkpoints in interactive

245 theory development.

248 *** Locales ***

250 * New commands for the interpretation of locale expressions in

251 theories (1), locales (2) and proof contexts (3). These generate

252 proof obligations from the expression specification. After the

253 obligations have been discharged, theorems of the expression are added

254 to the theory, target locale or proof context. The synopsis of the

255 commands is a follows:

257 (1) interpretation expr inst

258 (2) interpretation target < expr

259 (3) interpret expr inst

261 Interpretation in theories and proof contexts require a parameter

262 instantiation of terms from the current context. This is applied to

263 specifications and theorems of the interpreted expression.

264 Interpretation in locales only permits parameter renaming through the

265 locale expression. Interpretation is smart in that interpretations

266 that are active already do not occur in proof obligations, neither are

267 instantiated theorems stored in duplicate. Use 'print_interps' to

268 inspect active interpretations of a particular locale. For details,

269 see the Isar Reference manual. Examples can be found in

270 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.

272 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use

273 'interpret' instead.

275 * New context element 'constrains' for adding type constraints to

276 parameters.

278 * Context expressions: renaming of parameters with syntax

279 redeclaration.

281 * Locale declaration: 'includes' disallowed.

283 * Proper static binding of attribute syntax -- i.e. types / terms /

284 facts mentioned as arguments are always those of the locale definition

285 context, independently of the context of later invocations. Moreover,

286 locale operations (renaming and type / term instantiation) are applied

287 to attribute arguments as expected.

289 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of

290 actual attributes; rare situations may require Attrib.attribute to

291 embed those attributes into Attrib.src that lack concrete syntax.

292 Attribute implementations need to cooperate properly with the static

293 binding mechanism. Basic parsers Args.XXX_typ/term/prop and

294 Attrib.XXX_thm etc. already do the right thing without further

295 intervention. Only unusual applications -- such as "where" or "of"

296 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both

297 on the context and the facts involved -- may have to assign parsed

298 values to argument tokens explicitly.

300 * Changed parameter management in theorem generation for long goal

301 statements with 'includes'. INCOMPATIBILITY: produces a different

302 theorem statement in rare situations.

304 * Locale inspection command 'print_locale' omits notes elements. Use

305 'print_locale!' to have them included in the output.

308 *** Provers ***

310 * Provers/hypsubst.ML: improved version of the subst method, for

311 single-step rewriting: it now works in bound variable contexts. New is

312 'subst (asm)', for rewriting an assumption. INCOMPATIBILITY: may

313 rewrite a different subterm than the original subst method, which is

314 still available as 'simplesubst'.

316 * Provers/quasi.ML: new transitivity reasoners for transitivity only

317 and quasi orders.

319 * Provers/trancl.ML: new transitivity reasoner for transitive and

320 reflexive-transitive closure of relations.

322 * Provers/blast.ML: new reference depth_limit to make blast's depth

323 limit (previously hard-coded with a value of 20) user-definable.

325 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup

326 is peformed already. Object-logics merely need to finish their

327 initial simpset configuration as before. INCOMPATIBILITY.

330 *** HOL ***

332 * Symbolic syntax of Hilbert Choice Operator is now as follows:

334 syntax (epsilon)

335 "_Eps" :: "[pttrn, bool] => 'a" ("(3\<some>_./ _)" [0, 10] 10)

337 The symbol \<some> is displayed as the alternative epsilon of LaTeX

338 and x-symbol; use option '-m epsilon' to get it actually printed.

339 Moreover, the mathematically important symbolic identifier \<epsilon>

340 becomes available as variable, constant etc. INCOMPATIBILITY,

342 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".

343 Similarly for all quantifiers: "ALL x > y" etc. The x-symbol for >=

344 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to

345 support corresponding Isar calculations.

347 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"

348 instead of ":".

350 * theory SetInterval: changed the syntax for open intervals:

352 Old New

353 {..n(} {..<n}

354 {)n..} {n<..}

355 {m..n(} {m..<n}

356 {)m..n} {m<..n}

357 {)m..n(} {m<..<n}

359 The old syntax is still supported but will disappear in the next

360 release. For conversion use the following Emacs search and replace

361 patterns (these are not perfect but work quite well):

363 {)\([^\.]*\)\.\. -> {\1<\.\.}

364 \.\.\([^(}]*\)(} -> \.\.<\1}

366 * Theory Commutative_Ring (in Library): method comm_ring for proving

367 equalities in commutative rings; method 'algebra' provides a generic

368 interface.

370 * Theory Finite_Set: changed the syntax for 'setsum', summation over

371 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is

372 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can

373 be a tuple pattern.

375 Some new syntax forms are available:

377 "\<Sum>x | P. e" for "setsum (%x. e) {x. P}"

378 "\<Sum>x = a..b. e" for "setsum (%x. e) {a..b}"

379 "\<Sum>x = a..<b. e" for "setsum (%x. e) {a..<b}"

380 "\<Sum>x < k. e" for "setsum (%x. e) {..<k}"

382 The latter form "\<Sum>x < k. e" used to be based on a separate

383 function "Summation", which has been discontinued.

385 * theory Finite_Set: in structured induction proofs, the insert case

386 is now 'case (insert x F)' instead of the old counterintuitive 'case

387 (insert F x)'.

389 * The 'refute' command has been extended to support a much larger

390 fragment of HOL, including axiomatic type classes, constdefs and

391 typedefs, inductive datatypes and recursion.

393 * Datatype induction via method 'induct' now preserves the name of the

394 induction variable. For example, when proving P(xs::'a list) by

395 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather

396 than P(list) ==> P(a#list) as previously. Potential INCOMPATIBILITY

397 in unstructured proof scripts.

399 * Reworked implementation of records. Improved scalability for

400 records with many fields, avoiding performance problems for type

401 inference. Records are no longer composed of nested field types, but

402 of nested extension types. Therefore the record type only grows linear

403 in the number of extensions and not in the number of fields. The

404 top-level (users) view on records is preserved. Potential

405 INCOMPATIBILITY only in strange cases, where the theory depends on the

406 old record representation. The type generated for a record is called

407 <record_name>_ext_type.

409 Flag record_quick_and_dirty_sensitive can be enabled to skip the

410 proofs triggered by a record definition or a simproc (if

411 quick_and_dirty is enabled). Definitions of large records can take

412 quite long.

414 New simproc record_upd_simproc for simplification of multiple record

415 updates enabled by default. Moreover, trivial updates are also

416 removed: r(|x := x r|) = r. INCOMPATIBILITY: old proofs break

417 occasionally, since simplification is more powerful by default.

419 * typedef: proper support for polymorphic sets, which contain extra

420 type-variables in the term.

422 * Simplifier: automatically reasons about transitivity chains

423 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics

424 provided by Provers/trancl.ML as additional solvers. INCOMPATIBILITY:

425 old proofs break occasionally as simplification may now solve more

426 goals than previously.

428 * Simplifier: converts x <= y into x = y if assumption y <= x is

429 present. Works for all partial orders (class "order"), in particular

430 numbers and sets. For linear orders (e.g. numbers) it treats ~ x < y

431 just like y <= x.

433 * Simplifier: new simproc for "let x = a in f x". If a is a free or

434 bound variable or a constant then the let is unfolded. Otherwise

435 first a is simplified to b, and then f b is simplified to g. If

436 possible we abstract b from g arriving at "let x = b in h x",

437 otherwise we unfold the let and arrive at g. The simproc can be

438 enabled/disabled by the reference use_let_simproc. Potential

439 INCOMPATIBILITY since simplification is more powerful by default.

441 * Classical reasoning: the meson method now accepts theorems as arguments.

443 * Theory OrderedGroup and Ring_and_Field: various additions and

444 improvements to faciliate calculations involving equalities and

445 inequalities.

447 The following theorems have been eliminated or modified

448 (INCOMPATIBILITY):

450 abs_eq now named abs_of_nonneg

451 abs_of_ge_0 now named abs_of_nonneg

452 abs_minus_eq now named abs_of_nonpos

453 imp_abs_id now named abs_of_nonneg

454 imp_abs_neg_id now named abs_of_nonpos

455 mult_pos now named mult_pos_pos

456 mult_pos_le now named mult_nonneg_nonneg

457 mult_pos_neg_le now named mult_nonneg_nonpos

458 mult_pos_neg2_le now named mult_nonneg_nonpos2

459 mult_neg now named mult_neg_neg

460 mult_neg_le now named mult_nonpos_nonpos

462 * Theory Parity: added rules for simplifying exponents.

464 * Theory List:

466 The following theorems have been eliminated or modified

467 (INCOMPATIBILITY):

469 list_all_Nil now named list_all.simps(1)

470 list_all_Cons now named list_all.simps(2)

471 list_all_conv now named list_all_iff

472 set_mem_eq now named mem_iff

474 * Theories SetsAndFunctions and BigO (see HOL/Library) support

475 asymptotic "big O" calculations. See the notes in BigO.thy.

478 *** HOL-Complex ***

480 * Theory RealDef: better support for embedding natural numbers and

481 integers in the reals.

483 The following theorems have been eliminated or modified

484 (INCOMPATIBILITY):

486 exp_ge_add_one_self now requires no hypotheses

487 real_of_int_add reversed direction of equality (use [symmetric])

488 real_of_int_minus reversed direction of equality (use [symmetric])

489 real_of_int_diff reversed direction of equality (use [symmetric])

490 real_of_int_mult reversed direction of equality (use [symmetric])

492 * Theory RComplete: expanded support for floor and ceiling functions.

494 * Theory Ln is new, with properties of the natural logarithm

496 * Hyperreal: There is a new type constructor "star" for making

497 nonstandard types. The old type names are now type synonyms:

499 hypreal = real star

500 hypnat = nat star

501 hcomplex = complex star

503 * Hyperreal: Many groups of similarly-defined constants have been

504 replaced by polymorphic versions (INCOMPATIBILITY):

506 star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex

508 starset <-- starsetNat, starsetC

509 *s* <-- *sNat*, *sc*

510 starset_n <-- starsetNat_n, starsetC_n

511 *sn* <-- *sNatn*, *scn*

512 InternalSets <-- InternalNatSets, InternalCSets

514 starfun <-- starfun{Nat,Nat2,C,RC,CR}

515 *f* <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*

516 starfun_n <-- starfun{Nat,Nat2,C,RC,CR}_n

517 *fn* <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*

518 InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs

520 * Hyperreal: Many type-specific theorems have been removed in favor of

521 theorems specific to various axiomatic type classes (INCOMPATIBILITY):

523 add_commute <-- {hypreal,hypnat,hcomplex}_add_commute

524 add_assoc <-- {hypreal,hypnat,hcomplex}_add_assocs

525 OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left

526 OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right

527 right_minus <-- hypreal_add_minus

528 left_minus <-- {hypreal,hcomplex}_add_minus_left

529 mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute

530 mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc

531 mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left

532 mult_1_right <-- hcomplex_mult_one_right

533 mult_zero_left <-- hcomplex_mult_zero_left

534 left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib

535 right_distrib <-- hypnat_add_mult_distrib2

536 zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one

537 right_inverse <-- hypreal_mult_inverse

538 left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left

539 order_refl <-- {hypreal,hypnat}_le_refl

540 order_trans <-- {hypreal,hypnat}_le_trans

541 order_antisym <-- {hypreal,hypnat}_le_anti_sym

542 order_less_le <-- {hypreal,hypnat}_less_le

543 linorder_linear <-- {hypreal,hypnat}_le_linear

544 add_left_mono <-- {hypreal,hypnat}_add_left_mono

545 mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2

546 add_nonneg_nonneg <-- hypreal_le_add_order

548 * Hyperreal: Separate theorems having to do with type-specific

549 versions of constants have been merged into theorems that apply to the

550 new polymorphic constants (INCOMPATIBILITY):

552 STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set

553 STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set

554 STAR_Un <-- {STAR,NatStar,STARC}_Un

555 STAR_Int <-- {STAR,NatStar,STARC}_Int

556 STAR_Compl <-- {STAR,NatStar,STARC}_Compl

557 STAR_subset <-- {STAR,NatStar,STARC}_subset

558 STAR_mem <-- {STAR,NatStar,STARC}_mem

559 STAR_mem_Compl <-- {STAR,STARC}_mem_Compl

560 STAR_diff <-- {STAR,STARC}_diff

561 STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,

562 STARC_hcomplex_of_complex}_image_subset

563 starset_n_Un <-- starset{Nat,C}_n_Un

564 starset_n_Int <-- starset{Nat,C}_n_Int

565 starset_n_Compl <-- starset{Nat,C}_n_Compl

566 starset_n_diff <-- starset{Nat,C}_n_diff

567 InternalSets_Un <-- Internal{Nat,C}Sets_Un

568 InternalSets_Int <-- Internal{Nat,C}Sets_Int

569 InternalSets_Compl <-- Internal{Nat,C}Sets_Compl

570 InternalSets_diff <-- Internal{Nat,C}Sets_diff

571 InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff

572 InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n

573 starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq

574 starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}

575 starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}

576 starfun <-- starfun{Nat,Nat2,C,RC,CR}

577 starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult

578 starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add

579 starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus

580 starfun_diff <-- starfun{C,RC,CR}_diff

581 starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o

582 starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2

583 starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun

584 starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse

585 starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq

586 starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff

587 starfun_Id <-- starfunC_Id

588 starfun_approx <-- starfun{Nat,CR}_approx

589 starfun_capprox <-- starfun{C,RC}_capprox

590 starfun_abs <-- starfunNat_rabs

591 starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel

592 starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2

593 starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox

594 starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox

595 starfun_add_capprox <-- starfun{C,RC}_add_capprox

596 starfun_add_approx <-- starfunCR_add_approx

597 starfun_inverse_inverse <-- starfunC_inverse_inverse

598 starfun_divide <-- starfun{C,CR,RC}_divide

599 starfun_n <-- starfun{Nat,C}_n

600 starfun_n_mult <-- starfun{Nat,C}_n_mult

601 starfun_n_add <-- starfun{Nat,C}_n_add

602 starfun_n_add_minus <-- starfunNat_n_add_minus

603 starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun

604 starfun_n_minus <-- starfun{Nat,C}_n_minus

605 starfun_n_eq <-- starfun{Nat,C}_n_eq

607 star_n_add <-- {hypreal,hypnat,hcomplex}_add

608 star_n_minus <-- {hypreal,hcomplex}_minus

609 star_n_diff <-- {hypreal,hcomplex}_diff

610 star_n_mult <-- {hypreal,hcomplex}_mult

611 star_n_inverse <-- {hypreal,hcomplex}_inverse

612 star_n_le <-- {hypreal,hypnat}_le

613 star_n_less <-- {hypreal,hypnat}_less

614 star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num

615 star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num

616 star_n_abs <-- hypreal_hrabs

617 star_n_divide <-- hcomplex_divide

619 star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add

620 star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus

621 star_of_diff <-- hypreal_of_real_diff

622 star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult

623 star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one

624 star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero

625 star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff

626 star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff

627 star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff

628 star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse

629 star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide

630 star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat

631 star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int

632 star_of_number_of <-- {hypreal,hcomplex}_number_of

633 star_of_number_less <-- number_of_less_hypreal_of_real_iff

634 star_of_number_le <-- number_of_le_hypreal_of_real_iff

635 star_of_eq_number <-- hypreal_of_real_eq_number_of_iff

636 star_of_less_number <-- hypreal_of_real_less_number_of_iff

637 star_of_le_number <-- hypreal_of_real_le_number_of_iff

638 star_of_power <-- hypreal_of_real_power

639 star_of_eq_0 <-- hcomplex_of_complex_zero_iff

641 * Hyperreal: new method "transfer" that implements the transfer

642 principle of nonstandard analysis. With a subgoal that mentions

643 nonstandard types like "'a star", the command "apply transfer"

644 replaces it with an equivalent one that mentions only standard types.

645 To be successful, all free variables must have standard types; non-

646 standard variables must have explicit universal quantifiers.

649 *** HOLCF ***

651 * Discontinued special version of 'constdefs' (which used to support

652 continuous functions) in favor of the general Pure one with full

653 type-inference.

655 * New simplification procedure for solving continuity conditions; it

656 is much faster on terms with many nested lambda abstractions (cubic

657 instead of exponential time).

659 * New syntax for domain package: selector names are now optional.

660 Parentheses should be omitted unless argument is lazy, for example:

662 domain 'a stream = cons "'a" (lazy "'a stream")

664 * New command 'fixrec' for defining recursive functions with pattern

665 matching; defining multiple functions with mutual recursion is also

666 supported. Patterns may include the constants cpair, spair, up, sinl,

667 sinr, or any data constructor defined by the domain package. The given

668 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for

669 syntax and examples.

671 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes

672 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,

673 but the proof obligation additionally includes an admissibility

674 requirement. The packages generate instances of class cpo or pcpo,

675 with continuity and strictness theorems for Rep and Abs.

678 *** ZF ***

680 * ZF/ex: theories Group and Ring provide examples in abstract algebra,

681 including the First Isomorphism Theorem (on quotienting by the kernel

682 of a homomorphism).

684 * ZF/Simplifier: install second copy of type solver that actually

685 makes use of TC rules declared to Isar proof contexts (or locales);

686 the old version is still required for ML proof scripts.

689 *** Cube ***

691 * Converted to Isar theory format; use locales instead of axiomatic

692 theories.

695 *** ML ***

697 * Pure/library.ML no longer defines its own option datatype, but uses

698 that of the SML basis, which has constructors NONE and SOME instead of

699 None and Some, as well as exception Option.Option instead of OPTION.

700 The functions the, if_none, is_some, is_none have been adapted

701 accordingly, while Option.map replaces apsome.

703 * Pure/library.ML: the exception LIST has been given up in favour of

704 the standard exceptions Empty and Subscript, as well as

705 Library.UnequalLengths. Function like Library.hd and Library.tl are

706 superceded by the standard hd and tl functions etc.

708 A number of basic list functions are no longer exported to the ML

709 toplevel, as they are variants of predefined functions. The following

710 suggests how one can translate existing code:

712 rev_append xs ys = List.revAppend (xs, ys)

713 nth_elem (i, xs) = List.nth (xs, i)

714 last_elem xs = List.last xs

715 flat xss = List.concat xss

716 seq fs = List.app fs

717 partition P xs = List.partition P xs

718 mapfilter f xs = List.mapPartial f xs

720 * Pure/library.ML: several combinators for linear functional

721 transformations, notably reverse application and composition:

723 x |> f f #> g

724 (x, y) |-> f f #-> g

726 * Pure/library.ML: introduced/changed precedence of infix operators:

728 infix 1 |> |-> ||> ||>> |>> |>>> #> #->;

729 infix 2 ?;

730 infix 3 o oo ooo oooo;

731 infix 4 ~~ upto downto;

733 Maybe INCOMPATIBILITY when any of those is used in conjunction with other

734 infix operators.

736 * Pure/library.ML: natural list combinators fold, fold_rev, and

737 fold_map support linear functional transformations and nesting. For

738 example:

740 fold f [x1, ..., xN] y =

741 y |> f x1 |> ... |> f xN

743 (fold o fold) f [xs1, ..., xsN] y =

744 y |> fold f xs1 |> ... |> fold f xsN

746 fold f [x1, ..., xN] =

747 f x1 #> ... #> f xN

749 (fold o fold) f [xs1, ..., xsN] =

750 fold f xs1 #> ... #> fold f xsN

752 * Pure/library.ML: the following selectors on type 'a option are

753 available:

755 the: 'a option -> 'a (*partial*)

756 these: 'a option -> 'a where 'a = 'b list

757 the_default: 'a -> 'a option -> 'a

758 the_list: 'a option -> 'a list

760 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides

761 basic operations for association lists, following natural argument

762 order; ; moreover the explicit equality predicate passed here avoids

763 potentially expensive polymorphic runtime equality checks.

764 The old functions may be expressed as follows:

766 assoc = uncurry (AList.lookup (op =))

767 assocs = these oo AList.lookup (op =)

768 overwrite = uncurry (AList.update (op =)) o swap

770 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)

771 provides a reasonably efficient light-weight implementation of sets as

772 lists.

774 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a

775 few new operations; existing lookup and update are now curried to

776 follow natural argument order (for use with fold etc.);

777 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.

779 * Pure/General: output via the Isabelle channels of

780 writeln/warning/error etc. is now passed through Output.output, with a

781 hook for arbitrary transformations depending on the print_mode

782 (cf. Output.add_mode -- the first active mode that provides a output

783 function wins). Already formatted output may be embedded into further

784 text via Output.raw; the result of Pretty.string_of/str_of and derived

785 functions (string_of_term/cterm/thm etc.) is already marked raw to

786 accommodate easy composition of diagnostic messages etc. Programmers

787 rarely need to care about Output.output or Output.raw at all, with

788 some notable exceptions: Output.output is required when bypassing the

789 standard channels (writeln etc.), or in token translations to produce

790 properly formatted results; Output.raw is required when capturing

791 already output material that will eventually be presented to the user

792 a second time. For the default print mode, both Output.output and

793 Output.raw have no effect.

795 * Pure/General: Output.time_accumulator NAME creates an operator ('a

796 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the

797 cumulative results are displayed at the end of a batch session.

799 * Pure/General: File.sysify_path and File.quote_sysify path have been

800 replaced by File.platform_path and File.shell_path (with appropriate

801 hooks). This provides a clean interface for unusual systems where the

802 internal and external process view of file names are different.

804 * Pure: more efficient orders for basic syntactic entities: added

805 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord

806 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is

807 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast

808 orders now -- potential INCOMPATIBILITY for code that depends on a

809 particular order for Symtab.keys, Symtab.dest, etc. (consider using

810 Library.sort_strings on result).

812 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,

813 fold_types traverse types/terms from left to right, observing natural

814 argument order. Supercedes previous foldl_XXX versions, add_frees,

815 add_vars etc. have been adapted as well: INCOMPATIBILITY.

817 * Pure: name spaces have been refined, with significant changes of the

818 internal interfaces -- INCOMPATIBILITY. Renamed cond_extern(_table)

819 to extern(_table). The plain name entry path is superceded by a

820 general 'naming' context, which also includes the 'policy' to produce

821 a fully qualified name and external accesses of a fully qualified

822 name; NameSpace.extend is superceded by context dependent

823 Sign.declare_name. Several theory and proof context operations modify

824 the naming context. Especially note Theory.restore_naming and

825 ProofContext.restore_naming to get back to a sane state; note that

826 Theory.add_path is no longer sufficient to recover from

827 Theory.absolute_path in particular.

829 * Pure: new flags short_names (default false) and unique_names

830 (default true) for controlling output of qualified names. If

831 short_names is set, names are printed unqualified. If unique_names is

832 reset, the name prefix is reduced to the minimum required to achieve

833 the original result when interning again, even if there is an overlap

834 with earlier declarations.

836 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is

837 now 'extend', and 'merge' gets an additional Pretty.pp argument

838 (useful for printing error messages). INCOMPATIBILITY.

840 * Pure: major reorganization of the theory context. Type Sign.sg and

841 Theory.theory are now identified, referring to the universal

842 Context.theory (see Pure/context.ML). Actual signature and theory

843 content is managed as theory data. The old code and interfaces were

844 spread over many files and structures; the new arrangement introduces

845 considerable INCOMPATIBILITY to gain more clarity:

847 Context -- theory management operations (name, identity, inclusion,

848 parents, ancestors, merge, etc.), plus generic theory data;

850 Sign -- logical signature and syntax operations (declaring consts,

851 types, etc.), plus certify/read for common entities;

853 Theory -- logical theory operations (stating axioms, definitions,

854 oracles), plus a copy of logical signature operations (consts,

855 types, etc.); also a few basic management operations (Theory.copy,

856 Theory.merge, etc.)

858 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm

859 etc.) as well as the sign field in Thm.rep_thm etc. have been retained

860 for convenience -- they merely return the theory.

862 * Pure: type Type.tsig is superceded by theory in most interfaces.

864 * Pure: the Isar proof context type is already defined early in Pure

865 as Context.proof (note that ProofContext.context and Proof.context are

866 aliases, where the latter is the preferred name). This enables other

867 Isabelle components to refer to that type even before Isar is present.

869 * Pure/sign/theory: discontinued named name spaces (i.e. classK,

870 typeK, constK, axiomK, oracleK), but provide explicit operations for

871 any of these kinds. For example, Sign.intern typeK is now

872 Sign.intern_type, Theory.hide_space Sign.typeK is now

873 Theory.hide_types. Also note that former

874 Theory.hide_classes/types/consts are now

875 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions

876 internalize their arguments! INCOMPATIBILITY.

878 * Pure: get_thm interface (of PureThy and ProofContext) expects

879 datatype thmref (with constructors Name and NameSelection) instead of

880 plain string -- INCOMPATIBILITY;

882 * Pure: cases produced by proof methods specify options, where NONE

883 means to remove case bindings -- INCOMPATIBILITY in

884 (RAW_)METHOD_CASES.

886 * Pure: the following operations retrieve axioms or theorems from a

887 theory node or theory hierarchy, respectively:

889 Theory.axioms_of: theory -> (string * term) list

890 Theory.all_axioms_of: theory -> (string * term) list

891 PureThy.thms_of: theory -> (string * thm) list

892 PureThy.all_thms_of: theory -> (string * thm) list

894 * Pure: print_tac now outputs the goal through the trace channel.

896 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.

897 Reference Toplevel.debug (default false) controls detailed printing

898 and tracing of low-level exceptions; Toplevel.profiling (default 0)

899 controls execution profiling -- set to 1 for time and 2 for space

900 (both increase the runtime).

902 * Isar session: The initial use of ROOT.ML is now always timed,

903 i.e. the log will show the actual process times, in contrast to the

904 elapsed wall-clock time that the outer shell wrapper produces.

906 * Simplifier: improved handling of bound variables (nameless

907 representation, avoid allocating new strings). Simprocs that invoke

908 the Simplifier recursively should use Simplifier.inherit_bounds to

909 avoid local name clashes.

911 * Provers: Simplifier and Classical Reasoner now support proof context

912 dependent plug-ins (simprocs, solvers, wrappers etc.). These extra

913 components are stored in the theory and patched into the

914 simpset/claset when used in an Isar proof context. Context dependent

915 components are maintained by the following theory operations:

917 Simplifier.add_context_simprocs

918 Simplifier.del_context_simprocs

919 Simplifier.set_context_subgoaler

920 Simplifier.reset_context_subgoaler

921 Simplifier.add_context_looper

922 Simplifier.del_context_looper

923 Simplifier.add_context_unsafe_solver

924 Simplifier.add_context_safe_solver

926 Classical.add_context_safe_wrapper

927 Classical.del_context_safe_wrapper

928 Classical.add_context_unsafe_wrapper

929 Classical.del_context_unsafe_wrapper

931 IMPORTANT NOTE: proof tools (methods etc.) need to use

932 local_simpset_of and local_claset_of to instead of the primitive

933 Simplifier.get_local_simpset and Classical.get_local_claset,

934 respectively, in order to see the context dependent fields!

936 * ML functions legacy_bindings and use_legacy_bindings produce ML fact

937 bindings for all theorems stored within a given theory; this may help

938 in porting non-Isar theories to Isar ones, while keeping ML proof

939 scripts for the time being.

941 * ML operator HTML.with_charset specifies the charset begin used for

942 generated HTML files. For example:

944 HTML.with_charset "utf-8" use_thy "Hebrew";

945 HTML.with_charset "utf-8" use_thy "Chinese";

948 *** System ***

950 * Allow symlinks to all proper Isabelle executables (Isabelle,

951 isabelle, isatool etc.).

953 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for

954 isatool doc, isatool mkdir, display_drafts etc.).

956 * isatool usedir: option -f allows specification of the ML file to be

957 used by Isabelle; default is ROOT.ML.

959 * New isatool version outputs the version identifier of the Isabelle

960 distribution being used.

962 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format

963 (containing Boolean satisfiability problems) into Isabelle/HOL

964 theories.

968 New in Isabelle2004 (April 2004)

969 --------------------------------

971 *** General ***

973 * Provers/order.ML: new efficient reasoner for partial and linear orders.

974 Replaces linorder.ML.

976 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic

977 (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler

978 (\<a>...\<z>), are now considered normal letters, and can therefore

979 be used anywhere where an ASCII letter (a...zA...Z) has until

980 now. COMPATIBILITY: This obviously changes the parsing of some

981 terms, especially where a symbol has been used as a binder, say

982 '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed

983 as an identifier. Fix it by inserting a space around former

984 symbols. Call 'isatool fixgreek' to try to fix parsing errors in

985 existing theory and ML files.

987 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.

989 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now

990 allowed in identifiers. Similar to Greek letters \<^isub> is now considered

991 a normal (but invisible) letter. For multiple letter subscripts repeat

992 \<^isub> like this: x\<^isub>1\<^isub>2.

994 * Pure: There are now sub-/superscripts that can span more than one

995 character. Text between \<^bsub> and \<^esub> is set in subscript in

996 ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in

997 superscript. The new control characters are not identifier parts.

999 * Pure: Control-symbols of the form \<^raw:...> will literally print the

1000 content of "..." to the latex file instead of \isacntrl... . The "..."

1001 may consist of any printable characters excluding the end bracket >.

1003 * Pure: Using new Isar command "finalconsts" (or the ML functions

1004 Theory.add_finals or Theory.add_finals_i) it is now possible to

1005 declare constants "final", which prevents their being given a definition

1006 later. It is useful for constants whose behaviour is fixed axiomatically

1007 rather than definitionally, such as the meta-logic connectives.

1009 * Pure: 'instance' now handles general arities with general sorts

1010 (i.e. intersections of classes),

1012 * Presentation: generated HTML now uses a CSS style sheet to make layout

1013 (somewhat) independent of content. It is copied from lib/html/isabelle.css.

1014 It can be changed to alter the colors/layout of generated pages.

1017 *** Isar ***

1019 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,

1020 cut_tac, subgoal_tac and thin_tac:

1021 - Now understand static (Isar) contexts. As a consequence, users of Isar

1022 locales are no longer forced to write Isar proof scripts.

1023 For details see Isar Reference Manual, paragraph 4.3.2: Further tactic

1024 emulations.

1025 - INCOMPATIBILITY: names of variables to be instantiated may no

1026 longer be enclosed in quotes. Instead, precede variable name with `?'.

1027 This is consistent with the instantiation attribute "where".

1029 * Attributes "where" and "of":

1030 - Now take type variables of instantiated theorem into account when reading

1031 the instantiation string. This fixes a bug that caused instantiated

1032 theorems to have too special types in some circumstances.

1033 - "where" permits explicit instantiations of type variables.

1035 * Calculation commands "moreover" and "also" no longer interfere with

1036 current facts ("this"), admitting arbitrary combinations with "then"

1037 and derived forms.

1039 * Locales:

1040 - Goal statements involving the context element "includes" no longer

1041 generate theorems with internal delta predicates (those ending on

1042 "_axioms") in the premise.

1043 Resolve particular premise with <locale>.intro to obtain old form.

1044 - Fixed bug in type inference ("unify_frozen") that prevented mix of target

1045 specification and "includes" elements in goal statement.

1046 - Rule sets <locale>.intro and <locale>.axioms no longer declared as

1047 [intro?] and [elim?] (respectively) by default.

1048 - Experimental command for instantiation of locales in proof contexts:

1049 instantiate <label>[<attrs>]: <loc>

1050 Instantiates locale <loc> and adds all its theorems to the current context

1051 taking into account their attributes. Label and attrs are optional

1052 modifiers, like in theorem declarations. If present, names of

1053 instantiated theorems are qualified with <label>, and the attributes

1054 <attrs> are applied after any attributes these theorems might have already.

1055 If the locale has assumptions, a chained fact of the form

1056 "<loc> t1 ... tn" is expected from which instantiations of the parameters

1057 are derived. The command does not support old-style locales declared

1058 with "locale (open)".

1059 A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.

1061 * HOL: Tactic emulation methods induct_tac and case_tac understand static

1062 (Isar) contexts.

1065 *** HOL ***

1067 * Proof import: new image HOL4 contains the imported library from

1068 the HOL4 system with about 2500 theorems. It is imported by

1069 replaying proof terms produced by HOL4 in Isabelle. The HOL4 image

1070 can be used like any other Isabelle image. See

1071 HOL/Import/HOL/README for more information.

1073 * Simplifier:

1074 - Much improved handling of linear and partial orders.

1075 Reasoners for linear and partial orders are set up for type classes

1076 "linorder" and "order" respectively, and are added to the default simpset

1077 as solvers. This means that the simplifier can build transitivity chains

1078 to solve goals from the assumptions.

1079 - INCOMPATIBILITY: old proofs break occasionally. Typically, applications

1080 of blast or auto after simplification become unnecessary because the goal

1081 is solved by simplification already.

1083 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,

1084 all proved in axiomatic type classes for semirings, rings and fields.

1086 * Numerics:

1087 - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are

1088 now formalized using the Ring_and_Field theory mentioned above.

1089 - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently

1090 than before, because now they are set up once in a generic manner.

1091 - INCOMPATIBILITY: many type-specific arithmetic laws have gone.

1092 Look for the general versions in Ring_and_Field (and Power if they concern

1093 exponentiation).

1095 * Type "rat" of the rational numbers is now available in HOL-Complex.

1097 * Records:

1098 - Record types are now by default printed with their type abbreviation

1099 instead of the list of all field types. This can be configured via

1100 the reference "print_record_type_abbr".

1101 - Simproc "record_upd_simproc" for simplification of multiple updates added

1102 (not enabled by default).

1103 - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.

1104 EX x. x = sel r to True (not enabled by default).

1105 - Tactic "record_split_simp_tac" to split and simplify records added.

1107 * 'specification' command added, allowing for definition by

1108 specification. There is also an 'ax_specification' command that

1109 introduces the new constants axiomatically.

1111 * arith(_tac) is now able to generate counterexamples for reals as well.

1113 * HOL-Algebra: new locale "ring" for non-commutative rings.

1115 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function

1116 definitions, thanks to Sava Krsti\'{c} and John Matthews.

1118 * HOL-Matrix: a first theory for matrices in HOL with an application of

1119 matrix theory to linear programming.

1121 * Unions and Intersections:

1122 The latex output syntax of UN and INT has been changed

1123 from "\Union x \in A. B" to "\Union_{x \in A} B"

1124 i.e. the index formulae has become a subscript.

1125 Similarly for "\Union x. B", and for \Inter instead of \Union.

1127 * Unions and Intersections over Intervals:

1128 There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is

1129 also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"

1130 like in normal math, and corresponding versions for < and for intersection.

1132 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard

1133 lexicographic dictonary ordering has been added as "lexord".

1135 * ML: the legacy theory structures Int and List have been removed. They had

1136 conflicted with ML Basis Library structures having the same names.

1138 * 'refute' command added to search for (finite) countermodels. Only works

1139 for a fragment of HOL. The installation of an external SAT solver is

1140 highly recommended. See "HOL/Refute.thy" for details.

1142 * 'quickcheck' command: Allows to find counterexamples by evaluating

1143 formulae under an assignment of free variables to random values.

1144 In contrast to 'refute', it can deal with inductive datatypes,

1145 but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"

1146 for examples.

1149 *** HOLCF ***

1151 * Streams now come with concatenation and are part of the HOLCF image

1155 New in Isabelle2003 (May 2003)

1156 ------------------------------

1158 *** General ***

1160 * Provers/simplifier:

1162 - Completely reimplemented method simp (ML: Asm_full_simp_tac):

1163 Assumptions are now subject to complete mutual simplification,

1164 not just from left to right. The simplifier now preserves

1165 the order of assumptions.

1167 Potential INCOMPATIBILITY:

1169 -- simp sometimes diverges where the old version did

1170 not, e.g. invoking simp on the goal

1172 [| P (f x); y = x; f x = f y |] ==> Q

1174 now gives rise to the infinite reduction sequence

1176 P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...

1178 Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this

1179 kind of problem.

1181 -- Tactics combining classical reasoner and simplification (such as auto)

1182 are also affected by this change, because many of them rely on

1183 simp. They may sometimes diverge as well or yield a different numbers

1184 of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto

1185 in case of problems. Sometimes subsequent calls to the classical

1186 reasoner will fail because a preceeding call to the simplifier too

1187 eagerly simplified the goal, e.g. deleted redundant premises.

1189 - The simplifier trace now shows the names of the applied rewrite rules

1191 - You can limit the number of recursive invocations of the simplifier

1192 during conditional rewriting (where the simplifie tries to solve the

1193 conditions before applying the rewrite rule):

1194 ML "simp_depth_limit := n"

1195 where n is an integer. Thus you can force termination where previously

1196 the simplifier would diverge.

1198 - Accepts free variables as head terms in congruence rules. Useful in Isar.

1200 - No longer aborts on failed congruence proof. Instead, the

1201 congruence is ignored.

1203 * Pure: New generic framework for extracting programs from constructive

1204 proofs. See HOL/Extraction.thy for an example instantiation, as well

1205 as HOL/Extraction for some case studies.

1207 * Pure: The main goal of the proof state is no longer shown by default, only

1208 the subgoals. This behaviour is controlled by a new flag.

1209 PG menu: Isabelle/Isar -> Settings -> Show Main Goal

1210 (ML: Proof.show_main_goal).

1212 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all

1213 rules whose conclusion matches subgoal 1:

1214 PG menu: Isabelle/Isar -> Show me -> matching rules

1215 The rules are ordered by how closely they match the subgoal.

1216 In particular, rules that solve a subgoal outright are displayed first

1217 (or rather last, the way they are printed).

1218 (ML: ProofGeneral.print_intros())

1220 * Pure: New flag trace_unify_fail causes unification to print

1221 diagnostic information (PG: in trace buffer) when it fails. This is

1222 useful for figuring out why single step proofs like rule, erule or

1223 assumption failed.

1225 * Pure: Locale specifications now produce predicate definitions

1226 according to the body of text (covering assumptions modulo local

1227 definitions); predicate "loc_axioms" covers newly introduced text,

1228 while "loc" is cumulative wrt. all included locale expressions; the

1229 latter view is presented only on export into the global theory

1230 context; potential INCOMPATIBILITY, use "(open)" option to fall back

1231 on the old view without predicates;

1233 * Pure: predefined locales "var" and "struct" are useful for sharing

1234 parameters (as in CASL, for example); just specify something like

1235 ``var x + var y + struct M'' as import;

1237 * Pure: improved thms_containing: proper indexing of facts instead of

1238 raw theorems; check validity of results wrt. current name space;

1239 include local facts of proof configuration (also covers active

1240 locales), cover fixed variables in index; may use "_" in term

1241 specification; an optional limit for the number of printed facts may

1242 be given (the default is 40);

1244 * Pure: disallow duplicate fact bindings within new-style theory files

1245 (batch-mode only);

1247 * Provers: improved induct method: assumptions introduced by case

1248 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from

1249 the goal statement); "foo" still refers to all facts collectively;

1251 * Provers: the function blast.overloaded has been removed: all constants

1252 are regarded as potentially overloaded, which improves robustness in exchange

1253 for slight decrease in efficiency;

1255 * Provers/linorder: New generic prover for transitivity reasoning over

1256 linear orders. Note: this prover is not efficient!

1258 * Isar: preview of problems to finish 'show' now produce an error

1259 rather than just a warning (in interactive mode);

1262 *** HOL ***

1264 * arith(_tac)

1266 - Produces a counter example if it cannot prove a goal.

1267 Note that the counter example may be spurious if the goal is not a formula

1268 of quantifier-free linear arithmetic.

1269 In ProofGeneral the counter example appears in the trace buffer.

1271 - Knows about div k and mod k where k is a numeral of type nat or int.

1273 - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free

1274 linear arithmetic fails. This takes account of quantifiers and divisibility.

1275 Presburger arithmetic can also be called explicitly via presburger(_tac).

1277 * simp's arithmetic capabilities have been enhanced a bit: it now

1278 takes ~= in premises into account (by performing a case split);

1280 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands

1281 are distributed over a sum of terms;

1283 * New tactic "trans_tac" and method "trans" instantiate

1284 Provers/linorder.ML for axclasses "order" and "linorder" (predicates

1285 "<=", "<" and "=").

1287 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main

1288 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";

1290 * 'typedef' command has new option "open" to suppress the set

1291 definition;

1293 * functions Min and Max on finite sets have been introduced (theory

1294 Finite_Set);

1296 * attribute [symmetric] now works for relations as well; it turns

1297 (x,y) : R^-1 into (y,x) : R, and vice versa;

1299 * induct over a !!-quantified statement (say !!x1..xn):

1300 each "case" automatically performs "fix x1 .. xn" with exactly those names.

1302 * Map: `empty' is no longer a constant but a syntactic abbreviation for

1303 %x. None. Warning: empty_def now refers to the previously hidden definition

1304 of the empty set.

1306 * Algebra: formalization of classical algebra. Intended as base for

1307 any algebraic development in Isabelle. Currently covers group theory

1308 (up to Sylow's theorem) and ring theory (Universal Property of

1309 Univariate Polynomials). Contributions welcome;

1311 * GroupTheory: deleted, since its material has been moved to Algebra;

1313 * Complex: new directory of the complex numbers with numeric constants,

1314 nonstandard complex numbers, and some complex analysis, standard and

1315 nonstandard (Jacques Fleuriot);

1317 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;

1319 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques

1320 Fleuriot);

1322 * Real/HahnBanach: updated and adapted to locales;

1324 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,

1325 Gray and Kramer);

1327 * UNITY: added the Meier-Sanders theory of progress sets;

1329 * MicroJava: bytecode verifier and lightweight bytecode verifier

1330 as abstract algorithms, instantiated to the JVM;

1332 * Bali: Java source language formalization. Type system, operational

1333 semantics, axiomatic semantics. Supported language features:

1334 classes, interfaces, objects,virtual methods, static methods,

1335 static/instance fields, arrays, access modifiers, definite

1336 assignment, exceptions.

1339 *** ZF ***

1341 * ZF/Constructible: consistency proof for AC (Gdel's constructible

1342 universe, etc.);

1344 * Main ZF: virtually all theories converted to new-style format;

1347 *** ML ***

1349 * Pure: Tactic.prove provides sane interface for internal proofs;

1350 omits the infamous "standard" operation, so this is more appropriate

1351 than prove_goalw_cterm in many situations (e.g. in simprocs);

1353 * Pure: improved error reporting of simprocs;

1355 * Provers: Simplifier.simproc(_i) provides sane interface for setting

1356 up simprocs;

1359 *** Document preparation ***

1361 * uses \par instead of \\ for line breaks in theory text. This may

1362 shift some page breaks in large documents. To get the old behaviour

1363 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.

1365 * minimized dependencies of isabelle.sty and isabellesym.sty on

1366 other packages

1368 * \<euro> now needs package babel/greek instead of marvosym (which

1369 broke \Rightarrow)

1371 * normal size for \<zero>...\<nine> (uses \mathbf instead of

1372 textcomp package)

1376 New in Isabelle2002 (March 2002)

1377 --------------------------------

1379 *** Document preparation ***

1381 * greatly simplified document preparation setup, including more

1382 graceful interpretation of isatool usedir -i/-d/-D options, and more

1383 instructive isatool mkdir; users should basically be able to get

1384 started with "isatool mkdir HOL Test && isatool make"; alternatively,

1385 users may run a separate document processing stage manually like this:

1386 "isatool usedir -D output HOL Test && isatool document Test/output";

1388 * theory dependency graph may now be incorporated into documents;

1389 isatool usedir -g true will produce session_graph.eps/.pdf for use

1390 with \includegraphics of LaTeX;

1392 * proper spacing of consecutive markup elements, especially text

1393 blocks after section headings;

1395 * support bold style (for single symbols only), input syntax is like

1396 this: "\<^bold>\<alpha>" or "\<^bold>A";

1398 * \<bullet> is now output as bold \cdot by default, which looks much

1399 better in printed text;

1401 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;

1402 note that these symbols are currently unavailable in Proof General /

1403 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;

1405 * isatool latex no longer depends on changed TEXINPUTS, instead

1406 isatool document copies the Isabelle style files to the target

1407 location;

1410 *** Isar ***

1412 * Pure/Provers: improved proof by cases and induction;

1413 - 'case' command admits impromptu naming of parameters (such as

1414 "case (Suc n)");

1415 - 'induct' method divinates rule instantiation from the inductive

1416 claim; no longer requires excessive ?P bindings for proper

1417 instantiation of cases;

1418 - 'induct' method properly enumerates all possibilities of set/type

1419 rules; as a consequence facts may be also passed through *type*

1420 rules without further ado;

1421 - 'induct' method now derives symbolic cases from the *rulified*

1422 rule (before it used to rulify cases stemming from the internal

1423 atomized version); this means that the context of a non-atomic

1424 statement becomes is included in the hypothesis, avoiding the

1425 slightly cumbersome show "PROP ?case" form;

1426 - 'induct' may now use elim-style induction rules without chaining

1427 facts, using ``missing'' premises from the goal state; this allows

1428 rules stemming from inductive sets to be applied in unstructured

1429 scripts, while still benefitting from proper handling of non-atomic

1430 statements; NB: major inductive premises need to be put first, all

1431 the rest of the goal is passed through the induction;

1432 - 'induct' proper support for mutual induction involving non-atomic

1433 rule statements (uses the new concept of simultaneous goals, see

1434 below);

1435 - append all possible rule selections, but only use the first

1436 success (no backtracking);

1437 - removed obsolete "(simplified)" and "(stripped)" options of methods;

1438 - undeclared rule case names default to numbers 1, 2, 3, ...;

1439 - added 'print_induct_rules' (covered by help item in recent Proof

1440 General versions);

1441 - moved induct/cases attributes to Pure, methods to Provers;

1442 - generic method setup instantiated for FOL and HOL;

1444 * Pure: support multiple simultaneous goal statements, for example

1445 "have a: A and b: B" (same for 'theorem' etc.); being a pure

1446 meta-level mechanism, this acts as if several individual goals had

1447 been stated separately; in particular common proof methods need to be

1448 repeated in order to cover all claims; note that a single elimination

1449 step is *not* sufficient to establish the two conjunctions, so this

1450 fails:

1452 assume "A & B" then have A and B .. (*".." fails*)

1454 better use "obtain" in situations as above; alternative refer to

1455 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;

1457 * Pure: proper integration with ``locales''; unlike the original

1458 version by Florian Kammller, Isar locales package high-level proof

1459 contexts rather than raw logical ones (e.g. we admit to include

1460 attributes everywhere); operations on locales include merge and

1461 rename; support for implicit arguments (``structures''); simultaneous

1462 type-inference over imports and text; see also HOL/ex/Locales.thy for

1463 some examples;

1465 * Pure: the following commands have been ``localized'', supporting a

1466 target locale specification "(in name)": 'lemma', 'theorem',

1467 'corollary', 'lemmas', 'theorems', 'declare'; the results will be

1468 stored both within the locale and at the theory level (exported and

1469 qualified by the locale name);

1471 * Pure: theory goals may now be specified in ``long'' form, with

1472 ad-hoc contexts consisting of arbitrary locale elements. for example

1473 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and

1474 definitions may be given, too); the result is a meta-level rule with

1475 the context elements being discharged in the obvious way;

1477 * Pure: new proof command 'using' allows to augment currently used

1478 facts after a goal statement ('using' is syntactically analogous to

1479 'apply', but acts on the goal's facts only); this allows chained facts

1480 to be separated into parts given before and after a claim, as in

1481 ``from a and b have C using d and e <proof>'';

1483 * Pure: renamed "antecedent" case to "rule_context";

1485 * Pure: new 'judgment' command records explicit information about the

1486 object-logic embedding (used by several tools internally); no longer

1487 use hard-wired "Trueprop";

1489 * Pure: added 'corollary' command;

1491 * Pure: fixed 'token_translation' command;

1493 * Pure: removed obsolete 'exported' attribute;

1495 * Pure: dummy pattern "_" in is/let is now automatically lifted over

1496 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")

1497 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");

1499 * Pure: method 'atomize' presents local goal premises as object-level

1500 statements (atomic meta-level propositions); setup controlled via

1501 rewrite rules declarations of 'atomize' attribute; example

1502 application: 'induct' method with proper rule statements in improper

1503 proof *scripts*;

1505 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)

1506 now consider the syntactic context of assumptions, giving a better

1507 chance to get type-inference of the arguments right (this is

1508 especially important for locales);

1510 * Pure: "sorry" no longer requires quick_and_dirty in interactive

1511 mode;

1513 * Pure/obtain: the formal conclusion "thesis", being marked as

1514 ``internal'', may no longer be reference directly in the text;

1515 potential INCOMPATIBILITY, may need to use "?thesis" in rare

1516 situations;

1518 * Pure: generic 'sym' attribute which declares a rule both as pure

1519 'elim?' and for the 'symmetric' operation;

1521 * Pure: marginal comments ``--'' may now occur just anywhere in the

1522 text; the fixed correlation with particular command syntax has been

1523 discontinued;

1525 * Pure: new method 'rules' is particularly well-suited for proof

1526 search in intuitionistic logic; a bit slower than 'blast' or 'fast',

1527 but often produces more compact proof terms with less detours;

1529 * Pure/Provers/classical: simplified integration with pure rule

1530 attributes and methods; the classical "intro?/elim?/dest?"

1531 declarations coincide with the pure ones; the "rule" method no longer

1532 includes classically swapped intros; "intro" and "elim" methods no

1533 longer pick rules from the context; also got rid of ML declarations

1534 AddXIs/AddXEs/AddXDs; all of this has some potential for

1535 INCOMPATIBILITY;

1537 * Provers/classical: attribute 'swapped' produces classical inversions

1538 of introduction rules;

1540 * Provers/simplifier: 'simplified' attribute may refer to explicit

1541 rules instead of full simplifier context; 'iff' attribute handles

1542 conditional rules;

1544 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;

1546 * HOL: 'recdef' now fails on unfinished automated proofs, use

1547 "(permissive)" option to recover old behavior;

1549 * HOL: 'inductive' no longer features separate (collective) attributes

1550 for 'intros' (was found too confusing);

1552 * HOL: properly declared induction rules less_induct and

1553 wf_induct_rule;

1556 *** HOL ***

1558 * HOL: moved over to sane numeral syntax; the new policy is as

1559 follows:

1561 - 0 and 1 are polymorphic constants, which are defined on any

1562 numeric type (nat, int, real etc.);

1564 - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based

1565 binary representation internally;

1567 - type nat has special constructor Suc, and generally prefers Suc 0

1568 over 1::nat and Suc (Suc 0) over 2::nat;

1570 This change may cause significant problems of INCOMPATIBILITY; here

1571 are some hints on converting existing sources:

1573 - due to the new "num" token, "-0" and "-1" etc. are now atomic

1574 entities, so expressions involving "-" (unary or binary minus) need

1575 to be spaced properly;

1577 - existing occurrences of "1" may need to be constraint "1::nat" or

1578 even replaced by Suc 0; similar for old "2";

1580 - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";

1582 - remove all special provisions on numerals in proofs;

1584 * HOL: simp rules nat_number expand numerals on nat to Suc/0

1585 representation (depends on bin_arith_simps in the default context);

1587 * HOL: symbolic syntax for x^2 (numeral 2);

1589 * HOL: the class of all HOL types is now called "type" rather than

1590 "term"; INCOMPATIBILITY, need to adapt references to this type class

1591 in axclass/classes, instance/arities, and (usually rare) occurrences

1592 in typings (of consts etc.); internally the class is called

1593 "HOL.type", ML programs should refer to HOLogic.typeS;

1595 * HOL/record package improvements:

1596 - new derived operations "fields" to build a partial record section,

1597 "extend" to promote a fixed record to a record scheme, and

1598 "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*

1599 declared as simp by default;

1600 - shared operations ("more", "fields", etc.) now need to be always

1601 qualified) --- potential INCOMPATIBILITY;

1602 - removed "make_scheme" operations (use "make" with "extend") --

1603 INCOMPATIBILITY;

1604 - removed "more" class (simply use "term") -- INCOMPATIBILITY;

1605 - provides cases/induct rules for use with corresponding Isar

1606 methods (for concrete records, record schemes, concrete more

1607 parts, and schematic more parts -- in that order);

1608 - internal definitions directly based on a light-weight abstract

1609 theory of product types over typedef rather than datatype;

1611 * HOL: generic code generator for generating executable ML code from

1612 specifications; specific support for HOL constructs such as inductive

1613 datatypes and sets, as well as recursive functions; can be invoked

1614 via 'generate_code' theory section;

1616 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);

1618 * HOL: consolidated and renamed several theories. In particular:

1619 Ord.thy has been absorbed into HOL.thy

1620 String.thy has been absorbed into List.thy

1622 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"

1623 (beware of argument permutation!);

1625 * HOL: linorder_less_split superseded by linorder_cases;

1627 * HOL/List: "nodups" renamed to "distinct";

1629 * HOL: added "The" definite description operator; move Hilbert's "Eps"

1630 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:

1631 - Ex_def has changed, now need to use some_eq_ex

1633 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so

1634 in this (rare) case use:

1636 delSWrapper "split_all_tac"

1637 addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)

1639 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS

1640 MAY FAIL;

1642 * HOL: introduced f^n = f o ... o f; warning: due to the limits of

1643 Isabelle's type classes, ^ on functions and relations has too general

1644 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be

1645 necessary to attach explicit type constraints;

1647 * HOL/Relation: the prefix name of the infix "O" has been changed from

1648 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been

1649 renamed accordingly (eg "compI" -> "rel_compI").

1651 * HOL: syntax translations now work properly with numerals and records

1652 expressions;

1654 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead

1655 of "lam" -- INCOMPATIBILITY;

1657 * HOL: got rid of some global declarations (potential INCOMPATIBILITY

1658 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"

1659 renamed "Product_Type.unit";

1661 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl

1663 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or

1664 the "cases" method);

1666 * HOL/GroupTheory: group theory examples including Sylow's theorem (by

1667 Florian Kammller);

1669 * HOL/IMP: updated and converted to new-style theory format; several

1670 parts turned into readable document, with proper Isar proof texts and

1671 some explanations (by Gerwin Klein);

1673 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);

1675 * HOL-Hyperreal is now a logic image;

1678 *** HOLCF ***

1680 * Isar: consts/constdefs supports mixfix syntax for continuous

1681 operations;

1683 * Isar: domain package adapted to new-style theory format, e.g. see

1684 HOLCF/ex/Dnat.thy;

1686 * theory Lift: proper use of rep_datatype lift instead of ML hacks --

1687 potential INCOMPATIBILITY; now use plain induct_tac instead of former

1688 lift.induct_tac, always use UU instead of Undef;

1690 * HOLCF/IMP: updated and converted to new-style theory;

1693 *** ZF ***

1695 * Isar: proper integration of logic-specific tools and packages,

1696 including theory commands '(co)inductive', '(co)datatype',

1697 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',

1698 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');

1700 * theory Main no longer includes AC; for the Axiom of Choice, base

1701 your theory on Main_ZFC;

1703 * the integer library now covers quotients and remainders, with many

1704 laws relating division to addition, multiplication, etc.;

1706 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a

1707 typeless version of the formalism;

1709 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory

1710 format;

1712 * ZF/Induct: new directory for examples of inductive definitions,

1713 including theory Multiset for multiset orderings; converted to

1714 new-style theory format;

1716 * ZF: many new theorems about lists, ordinals, etc.;

1719 *** General ***

1721 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference

1722 variable proof controls level of detail: 0 = no proofs (only oracle

1723 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see

1724 also ref manual for further ML interfaces;

1726 * Pure/axclass: removed obsolete ML interface

1727 goal_subclass/goal_arity;

1729 * Pure/syntax: new token syntax "num" for plain numerals (without "#"

1730 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now

1731 separate tokens, so expressions involving minus need to be spaced

1732 properly;

1734 * Pure/syntax: support non-oriented infixes, using keyword "infix"

1735 rather than "infixl" or "infixr";

1737 * Pure/syntax: concrete syntax for dummy type variables admits genuine

1738 sort constraint specifications in type inference; e.g. "x::_::foo"

1739 ensures that the type of "x" is of sort "foo" (but not necessarily a

1740 type variable);

1742 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"

1743 control output of nested => (types); the default behavior is

1744 "type_brackets";

1746 * Pure/syntax: builtin parse translation for "_constify" turns valued

1747 tokens into AST constants;

1749 * Pure/syntax: prefer later declarations of translations and print

1750 translation functions; potential INCOMPATIBILITY: need to reverse

1751 multiple declarations for same syntax element constant;

1753 * Pure/show_hyps reset by default (in accordance to existing Isar

1754 practice);

1756 * Provers/classical: renamed addaltern to addafter, addSaltern to

1757 addSafter;

1759 * Provers/clasimp: ``iff'' declarations now handle conditional rules

1760 as well;

1762 * system: tested support for MacOS X; should be able to get Isabelle +

1763 Proof General to work in a plain Terminal after installing Poly/ML

1764 (e.g. from the Isabelle distribution area) and GNU bash alone

1765 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol

1766 support requires further installations, e.g. from

1767 http://fink.sourceforge.net/);

1769 * system: support Poly/ML 4.1.1 (able to manage larger heaps);

1771 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead

1772 of 40 MB), cf. ML_OPTIONS;

1774 * system: Proof General keywords specification is now part of the

1775 Isabelle distribution (see etc/isar-keywords.el);

1777 * system: support for persistent Proof General sessions (refrain from

1778 outdating all loaded theories on startup); user may create writable

1779 logic images like this: ``isabelle -q HOL Test'';

1781 * system: smart selection of Isabelle process versus Isabelle

1782 interface, accommodates case-insensitive file systems (e.g. HFS+); may

1783 run both "isabelle" and "Isabelle" even if file names are badly

1784 damaged (executable inspects the case of the first letter of its own

1785 name); added separate "isabelle-process" and "isabelle-interface";

1787 * system: refrain from any attempt at filtering input streams; no

1788 longer support ``8bit'' encoding of old isabelle font, instead proper

1789 iso-latin characters may now be used; the related isatools

1790 "symbolinput" and "nonascii" have disappeared as well;

1792 * system: removed old "xterm" interface (the print modes "xterm" and

1793 "xterm_color" are still available for direct use in a suitable

1794 terminal);

1798 New in Isabelle99-2 (February 2001)

1799 -----------------------------------

1801 *** Overview of INCOMPATIBILITIES ***

1803 * HOL: please note that theories in the Library and elsewhere often use the

1804 new-style (Isar) format; to refer to their theorems in an ML script you must

1805 bind them to ML identifers by e.g. val thm_name = thm "thm_name";

1807 * HOL: inductive package no longer splits induction rule aggressively,

1808 but only as far as specified by the introductions given; the old

1809 format may be recovered via ML function complete_split_rule or attribute

1810 'split_rule (complete)';

1812 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,

1813 gfp_Tarski to gfp_unfold;

1815 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;

1817 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a

1818 relation); infix "^^" has been renamed "``"; infix "``" has been

1819 renamed "`"; "univalent" has been renamed "single_valued";

1821 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"

1822 operation;

1824 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;

1826 * Isar: 'obtain' no longer declares "that" fact as simp/intro;

1828 * Isar/HOL: method 'induct' now handles non-atomic goals; as a

1829 consequence, it is no longer monotonic wrt. the local goal context

1830 (which is now passed through the inductive cases);

1832 * Document preparation: renamed standard symbols \<ll> to \<lless> and

1833 \<gg> to \<ggreater>;

1836 *** Document preparation ***

1838 * \isabellestyle{NAME} selects version of Isabelle output (currently

1839 available: are "it" for near math-mode best-style output, "sl" for

1840 slanted text style, and "tt" for plain type-writer; if no

1841 \isabellestyle command is given, output is according to slanted

1842 type-writer);

1844 * support sub/super scripts (for single symbols only), input syntax is

1845 like this: "A\<^sup>*" or "A\<^sup>\<star>";

1847 * some more standard symbols; see Appendix A of the system manual for

1848 the complete list of symbols defined in isabellesym.sty;

1850 * improved isabelle style files; more abstract symbol implementation

1851 (should now use \isamath{...} and \isatext{...} in custom symbol

1852 definitions);

1854 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals

1855 state; Note that presentation of goal states does not conform to

1856 actual human-readable proof documents. Please do not include goal

1857 states into document output unless you really know what you are doing!

1859 * proper indentation of antiquoted output with proportional LaTeX

1860 fonts;

1862 * no_document ML operator temporarily disables LaTeX document

1863 generation;

1865 * isatool unsymbolize tunes sources for plain ASCII communication;

1868 *** Isar ***

1870 * Pure: Isar now suffers initial goal statements to contain unbound

1871 schematic variables (this does not conform to actual readable proof

1872 documents, due to unpredictable outcome and non-compositional proof

1873 checking); users who know what they are doing may use schematic goals

1874 for Prolog-style synthesis of proven results;

1876 * Pure: assumption method (an implicit finishing) now handles actual

1877 rules as well;

1879 * Pure: improved 'obtain' --- moved to Pure, insert "that" into

1880 initial goal, declare "that" only as Pure intro (only for single

1881 steps); the "that" rule assumption may now be involved in implicit

1882 finishing, thus ".." becomes a feasible for trivial obtains;

1884 * Pure: default proof step now includes 'intro_classes'; thus trivial

1885 instance proofs may be performed by "..";

1887 * Pure: ?thesis / ?this / "..." now work for pure meta-level

1888 statements as well;

1890 * Pure: more robust selection of calculational rules;

1892 * Pure: the builtin notion of 'finished' goal now includes the ==-refl

1893 rule (as well as the assumption rule);

1895 * Pure: 'thm_deps' command visualizes dependencies of theorems and

1896 lemmas, using the graph browser tool;

1898 * Pure: predict failure of "show" in interactive mode;

1900 * Pure: 'thms_containing' now takes actual terms as arguments;

1902 * HOL: improved method 'induct' --- now handles non-atomic goals

1903 (potential INCOMPATIBILITY); tuned error handling;

1905 * HOL: cases and induct rules now provide explicit hints about the

1906 number of facts to be consumed (0 for "type" and 1 for "set" rules);

1907 any remaining facts are inserted into the goal verbatim;

1909 * HOL: local contexts (aka cases) may now contain term bindings as

1910 well; the 'cases' and 'induct' methods new provide a ?case binding for

1911 the result to be shown in each case;

1913 * HOL: added 'recdef_tc' command;

1915 * isatool convert assists in eliminating legacy ML scripts;

1918 *** HOL ***

1920 * HOL/Library: a collection of generic theories to be used together

1921 with main HOL; the theory loader path already includes this directory

1922 by default; the following existing theories have been moved here:

1923 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While

1924 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);

1926 * HOL/Unix: "Some aspects of Unix file-system security", a typical

1927 modelling and verification task performed in Isabelle/HOL +

1928 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).

1930 * HOL/Algebra: special summation operator SUM no longer exists, it has

1931 been replaced by setsum; infix 'assoc' now has priority 50 (like

1932 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to

1933 'domain', this makes the theory consistent with mathematical

1934 literature;

1936 * HOL basics: added overloaded operations "inverse" and "divide"

1937 (infix "/"), syntax for generic "abs" operation, generic summation

1938 operator \<Sum>;

1940 * HOL/typedef: simplified package, provide more useful rules (see also

1941 HOL/subset.thy);

1943 * HOL/datatype: induction rule for arbitrarily branching datatypes is

1944 now expressed as a proper nested rule (old-style tactic scripts may

1945 require atomize_strip_tac to cope with non-atomic premises);

1947 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule

1948 to "split_conv" (old name still available for compatibility);

1950 * HOL: improved concrete syntax for strings (e.g. allows translation

1951 rules with string literals);

1953 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals

1954 and Fleuriot's mechanization of analysis, including the transcendental

1955 functions for the reals;

1957 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;

1960 *** CTT ***

1962 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that

1963 "lam" is displayed as TWO lambda-symbols

1965 * CTT: theory Main now available, containing everything (that is, Bool

1966 and Arith);

1969 *** General ***

1971 * Pure: the Simplifier has been implemented properly as a derived rule

1972 outside of the actual kernel (at last!); the overall performance

1973 penalty in practical applications is about 50%, while reliability of

1974 the Isabelle inference kernel has been greatly improved;

1976 * print modes "brackets" and "no_brackets" control output of nested =>

1977 (types) and ==> (props); the default behaviour is "brackets";

1979 * Provers: fast_tac (and friends) now handle actual object-logic rules

1980 as assumptions as well;

1982 * system: support Poly/ML 4.0;

1984 * system: isatool install handles KDE version 1 or 2;

1988 New in Isabelle99-1 (October 2000)

1989 ----------------------------------

1991 *** Overview of INCOMPATIBILITIES ***

1993 * HOL: simplification of natural numbers is much changed; to partly

1994 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)

1995 issue the following ML commands:

1997 Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;

1998 Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];

2000 * HOL: simplification no longer dives into case-expressions; this is

2001 controlled by "t.weak_case_cong" for each datatype t;

2003 * HOL: nat_less_induct renamed to less_induct;

2005 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool

2006 fixsome to patch .thy and .ML sources automatically;

2008 select_equality -> some_equality

2009 select_eq_Ex -> some_eq_ex

2010 selectI2EX -> someI2_ex

2011 selectI2 -> someI2

2012 selectI -> someI

2013 select1_equality -> some1_equality

2014 Eps_sym_eq -> some_sym_eq_trivial

2015 Eps_eq -> some_eq_trivial

2017 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;

2019 * HOL: removed obsolete theorem binding expand_if (refer to split_if

2020 instead);

2022 * HOL: the recursion equations generated by 'recdef' are now called

2023 f.simps instead of f.rules;

2025 * HOL: qed_spec_mp now also handles bounded ALL as well;

2027 * HOL: 0 is now overloaded, so the type constraint ":: nat" may

2028 sometimes be needed;

2030 * HOL: the constant for "f``x" is now "image" rather than "op ``";

2032 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";

2034 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian

2035 product is now "<*>" instead of "Times"; the lexicographic product is

2036 now "<*lex*>" instead of "**";

2038 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part

2039 of main HOL, but was unused); better use HOL's datatype package;

2041 * HOL: removed "symbols" syntax for constant "override" of theory Map;

2042 the old syntax may be recovered as follows:

2044 syntax (symbols)

2045 override :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"

2046 (infixl "\\<oplus>" 100)

2048 * HOL/Real: "rabs" replaced by overloaded "abs" function;

2050 * HOL/ML: even fewer consts are declared as global (see theories Ord,

2051 Lfp, Gfp, WF); this only affects ML packages that refer to const names

2052 internally;

2054 * HOL and ZF: syntax for quotienting wrt an equivalence relation

2055 changed from A/r to A//r;

2057 * ZF: new treatment of arithmetic (nat & int) may break some old

2058 proofs;

2060 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,

2061 rulify -> rule_format, elimify -> elim_format, ...);

2063 * Isar/Provers: intro/elim/dest attributes changed; renamed

2064 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one

2065 should have to change intro!! to intro? only); replaced "delrule" by

2066 "rule del";

2068 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;

2070 * Provers: strengthened force_tac by using new first_best_tac;

2072 * LaTeX document preparation: several changes of isabelle.sty (see

2073 lib/texinputs);

2076 *** Document preparation ***

2078 * formal comments (text blocks etc.) in new-style theories may now

2079 contain antiquotations of thm/prop/term/typ/text to be presented

2080 according to latex print mode; concrete syntax is like this:

2081 @{term[show_types] "f(x) = a + x"};

2083 * isatool mkdir provides easy setup of Isabelle session directories,

2084 including proper document sources;

2086 * generated LaTeX sources are now deleted after successful run

2087 (isatool document -c); may retain a copy somewhere else via -D option

2088 of isatool usedir;

2090 * isatool usedir -D now lets isatool latex -o sty update the Isabelle

2091 style files, achieving self-contained LaTeX sources and simplifying

2092 LaTeX debugging;

2094 * old-style theories now produce (crude) LaTeX output as well;

2096 * browser info session directories are now self-contained (may be put

2097 on WWW server seperately); improved graphs of nested sessions; removed

2098 graph for 'all sessions';

2100 * several improvements in isabelle style files; \isabellestyle{it}

2101 produces fake math mode output; \isamarkupheader is now \section by

2102 default; see lib/texinputs/isabelle.sty etc.;

2105 *** Isar ***

2107 * Isar/Pure: local results and corresponding term bindings are now

2108 subject to Hindley-Milner polymorphism (similar to ML); this

2109 accommodates incremental type-inference very nicely;

2111 * Isar/Pure: new derived language element 'obtain' supports

2112 generalized existence reasoning;

2114 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'

2115 support accumulation of results, without applying any rules yet;

2116 useful to collect intermediate results without explicit name

2117 references, and for use with transitivity rules with more than 2

2118 premises;

2120 * Isar/Pure: scalable support for case-analysis type proofs: new

2121 'case' language element refers to local contexts symbolically, as

2122 produced by certain proof methods; internally, case names are attached

2123 to theorems as "tags";

2125 * Isar/Pure: theory command 'hide' removes declarations from

2126 class/type/const name spaces;

2128 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to

2129 indicate potential overloading;

2131 * Isar/Pure: changed syntax of local blocks from {{ }} to { };

2133 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write

2134 "{a,b,c}" instead of {a,b,c};

2136 * Isar/Pure now provides its own version of intro/elim/dest

2137 attributes; useful for building new logics, but beware of confusion

2138 with the version in Provers/classical;

2140 * Isar/Pure: the local context of (non-atomic) goals is provided via

2141 case name 'antecedent';

2143 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms

2144 to the current context is now done automatically);

2146 * Isar/Pure: theory command 'method_setup' provides a simple interface

2147 for definining proof methods in ML;

2149 * Isar/Provers: intro/elim/dest attributes changed; renamed

2150 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in

2151 most cases, one should have to change intro!! to intro? only);

2152 replaced "delrule" by "rule del";

2154 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and

2155 'symmetric' attribute (the latter supercedes [RS sym]);

2157 * Isar/Provers: splitter support (via 'split' attribute and 'simp'

2158 method modifier); 'simp' method: 'only:' modifier removes loopers as

2159 well (including splits);

2161 * Isar/Provers: Simplifier and Classical methods now support all kind

2162 of modifiers used in the past, including 'cong', 'iff', etc.

2164 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination

2165 of Simplifier and Classical reasoner);

2167 * Isar/HOL: new proof method 'cases' and improved version of 'induct'

2168 now support named cases; major packages (inductive, datatype, primrec,

2169 recdef) support case names and properly name parameters;

2171 * Isar/HOL: new transitivity rules for substitution in inequalities --

2172 monotonicity conditions are extracted to be proven at end of

2173 calculations;

2175 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof

2176 method anyway;

2178 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =

2179 split_if split_if_asm; datatype package provides theorems foo.splits =

2180 foo.split foo.split_asm for each datatype;

2182 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"

2183 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof

2184 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:

2185 use "(cases (simplified))" method in proper proof texts);

2187 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;

2189 * Isar: names of theorems etc. may be natural numbers as well;

2191 * Isar: 'pr' command: optional arguments for goals_limit and

2192 ProofContext.prems_limit; no longer prints theory contexts, but only

2193 proof states;

2195 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit

2196 additional print modes to be specified; e.g. "pr(latex)" will print

2197 proof state according to the Isabelle LaTeX style;

2199 * Isar: improved support for emulating tactic scripts, including proof

2200 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',

2201 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'

2202 (for HOL datatypes);

2204 * Isar: simplified (more robust) goal selection of proof methods: 1st

2205 goal, all goals, or explicit goal specifier (tactic emulation); thus

2206 'proof method scripts' have to be in depth-first order;

2208 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';

2210 * Isar: removed 'help' command, which hasn't been too helpful anyway;

2211 should instead use individual commands for printing items

2212 (print_commands, print_methods etc.);

2214 * Isar: added 'nothing' --- the empty list of theorems;

2217 *** HOL ***

2219 * HOL/MicroJava: formalization of a fragment of Java, together with a

2220 corresponding virtual machine and a specification of its bytecode

2221 verifier and a lightweight bytecode verifier, including proofs of

2222 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and

2223 Cornelia Pusch (see also the homepage of project Bali at

2224 http://isabelle.in.tum.de/Bali/);

2226 * HOL/Algebra: new theory of rings and univariate polynomials, by

2227 Clemens Ballarin;

2229 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese

2230 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M

2231 Rasmussen;

2233 * HOL/Lattice: fundamental concepts of lattice theory and order

2234 structures, including duals, properties of bounds versus algebraic

2235 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski

2236 Theorem for complete lattices etc.; may also serve as a demonstration

2237 for abstract algebraic reasoning using axiomatic type classes, and

2238 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;

2240 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David

2241 von Oheimb;

2243 * HOL/IMPP: extension of IMP with local variables and mutually

2244 recursive procedures, by David von Oheimb;

2246 * HOL/Lambda: converted into new-style theory and document;

2248 * HOL/ex/Multiquote: example of multiple nested quotations and

2249 anti-quotations -- basically a generalized version of de-Bruijn

2250 representation; very useful in avoiding lifting of operations;

2252 * HOL/record: added general record equality rule to simpset; fixed

2253 select-update simplification procedure to handle extended records as

2254 well; admit "r" as field name;

2256 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with

2257 other numeric types and also as the identity of groups, rings, etc.;

2259 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.

2260 Types nat and int belong to this axclass;

2262 * HOL: greatly improved simplification involving numerals of type nat, int, real:

2263 (i + #8 + j) = Suc k simplifies to #7 + (i + j) = k

2264 i*j + k + j*#3*i simplifies to #4*(i*j) + k

2265 two terms #m*u and #n*u are replaced by #(m+n)*u

2266 (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)

2267 and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y

2268 or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);

2270 * HOL: meson_tac is available (previously in ex/meson.ML); it is a

2271 powerful prover for predicate logic but knows nothing of clasets; see

2272 ex/mesontest.ML and ex/mesontest2.ML for example applications;

2274 * HOL: new version of "case_tac" subsumes both boolean case split and

2275 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer

2276 exists, may define val exhaust_tac = case_tac for ad-hoc portability;

2278 * HOL: simplification no longer dives into case-expressions: only the

2279 selector expression is simplified, but not the remaining arms; to

2280 enable full simplification of case-expressions for datatype t, you may

2281 remove t.weak_case_cong from the simpset, either globally (Delcongs

2282 [thm"t.weak_case_cong"];) or locally (delcongs [...]).

2284 * HOL/recdef: the recursion equations generated by 'recdef' for

2285 function 'f' are now called f.simps instead of f.rules; if all

2286 termination conditions are proved automatically, these simplification

2287 rules are added to the simpset, as in primrec; rules may be named

2288 individually as well, resulting in a separate list of theorems for

2289 each equation;

2291 * HOL/While is a new theory that provides a while-combinator. It

2292 permits the definition of tail-recursive functions without the

2293 provision of a termination measure. The latter is necessary once the

2294 invariant proof rule for while is applied.

2296 * HOL: new (overloaded) notation for the set of elements below/above

2297 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.

2299 * HOL: theorems impI, allI, ballI bound as "strip";

2301 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic

2302 induct_tac th "x1 ... xn" expects th to have a conclusion of the form

2303 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;

2305 * HOL/Real: "rabs" replaced by overloaded "abs" function;

2307 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of

2308 main HOL, but was unused);

2310 * HOL: fewer consts declared as global (e.g. have to refer to

2311 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);

2313 * HOL: tuned AST representation of nested pairs, avoiding bogus output

2314 in case of overlap with user translations (e.g. judgements over

2315 tuples); (note that the underlying logical represenation is still

2316 bogus);

2319 *** ZF ***

2321 * ZF: simplification automatically cancels common terms in arithmetic

2322 expressions over nat and int;

2324 * ZF: new treatment of nat to minimize type-checking: all operators

2325 coerce their operands to a natural number using the function natify,

2326 making the algebraic laws unconditional;

2328 * ZF: as above, for int: operators coerce their operands to an integer

2329 using the function intify;

2331 * ZF: the integer library now contains many of the usual laws for the

2332 orderings, including $<=, and monotonicity laws for $+ and $*;

2334 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic

2335 simplification;

2337 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q

2338 to the simplifier and classical reasoner simultaneously;

2341 *** General ***

2343 * Provers: blast_tac now handles actual object-logic rules as

2344 assumptions; note that auto_tac uses blast_tac internally as well;

2346 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning

2347 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;

2349 * Provers: delrules now handles destruct rules as well (no longer need

2350 explicit make_elim);

2352 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.

2353 [| inj ?f; ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W

2354 use instead the strong form,

2355 [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W

2356 in HOL, FOL and ZF the function cla_make_elim will create such rules

2357 from destruct-rules;

2359 * Provers: Simplifier.easy_setup provides a fast path to basic

2360 Simplifier setup for new object-logics;

2362 * Pure: AST translation rules no longer require constant head on LHS;

2364 * Pure: improved name spaces: ambiguous output is qualified; support

2365 for hiding of names;

2367 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and

2368 XSYMBOL_HOME; no longer need to do manual configuration in most

2369 situations;

2371 * system: compression of ML heaps images may now be controlled via -c

2372 option of isabelle and isatool usedir (currently only observed by

2373 Poly/ML);

2375 * system: isatool installfonts may handle X-Symbol fonts as well (very

2376 useful for remote X11);

2378 * system: provide TAGS file for Isabelle sources;

2380 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument

2381 order;

2383 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global

2384 timing flag supersedes proof_timing and Toplevel.trace;

2386 * ML: new combinators |>> and |>>> for incremental transformations

2387 with secondary results (e.g. certain theory extensions):

2389 * ML: PureThy.add_defs gets additional argument to indicate potential

2390 overloading (usually false);

2392 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as

2393 results;

2397 New in Isabelle99 (October 1999)

2398 --------------------------------

2400 *** Overview of INCOMPATIBILITIES (see below for more details) ***

2402 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)

2403 are no longer simplified. (This allows the simplifier to unfold recursive

2404 functional programs.) To restore the old behaviour, declare

2406 Delcongs [if_weak_cong];

2408 * HOL: Removed the obsolete syntax "Compl A"; use -A for set

2409 complement;

2411 * HOL: the predicate "inj" is now defined by translation to "inj_on";

2413 * HOL/datatype: mutual_induct_tac no longer exists --

2414 use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]

2416 * HOL/typedef: fixed type inference for representing set; type

2417 arguments now have to occur explicitly on the rhs as type constraints;

2419 * ZF: The con_defs part of an inductive definition may no longer refer

2420 to constants declared in the same theory;

2422 * HOL, ZF: the function mk_cases, generated by the inductive

2423 definition package, has lost an argument. To simplify its result, it

2424 uses the default simpset instead of a supplied list of theorems.

2426 * HOL/List: the constructors of type list are now Nil and Cons;

2428 * Simplifier: the type of the infix ML functions

2429 setSSolver addSSolver setSolver addSolver

2430 is now simpset * solver -> simpset where `solver' is a new abstract type

2431 for packaging solvers. A solver is created via

2432 mk_solver: string -> (thm list -> int -> tactic) -> solver

2433 where the string argument is only a comment.

2436 *** Proof tools ***

2438 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a

2439 decision procedure for linear arithmetic. Currently it is used for

2440 types `nat', `int', and `real' in HOL (see below); it can, should and

2441 will be instantiated for other types and logics as well.

2443 * The simplifier now accepts rewrite rules with flexible heads, eg

2444 hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y

2445 They are applied like any rule with a non-pattern lhs, i.e. by first-order

2446 matching.

2449 *** General ***

2451 * New Isabelle/Isar subsystem provides an alternative to traditional

2452 tactical theorem proving; together with the ProofGeneral/isar user

2453 interface it offers an interactive environment for developing human

2454 readable proof documents (Isar == Intelligible semi-automated

2455 reasoning); for further information see isatool doc isar-ref,

2456 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/

2458 * improved and simplified presentation of theories: better HTML markup

2459 (including colors), graph views in several sizes; isatool usedir now

2460 provides a proper interface for user theories (via -P option); actual

2461 document preparation based on (PDF)LaTeX is available as well (for

2462 new-style theories only); see isatool doc system for more information;

2464 * native support for Proof General, both for classic Isabelle and

2465 Isabelle/Isar;

2467 * ML function thm_deps visualizes dependencies of theorems and lemmas,

2468 using the graph browser tool;

2470 * Isabelle manuals now also available as PDF;

2472 * theory loader rewritten from scratch (may not be fully

2473 bug-compatible); old loadpath variable has been replaced by show_path,

2474 add_path, del_path, reset_path functions; new operations such as

2475 update_thy, touch_thy, remove_thy, use/update_thy_only (see also

2476 isatool doc ref);

2478 * improved isatool install: option -k creates KDE application icon,

2479 option -p DIR installs standalone binaries;

2481 * added ML_PLATFORM setting (useful for cross-platform installations);

2482 more robust handling of platform specific ML images for SML/NJ;

2484 * the settings environment is now statically scoped, i.e. it is never

2485 created again in sub-processes invoked from isabelle, isatool, or

2486 Isabelle;

2488 * path element specification '~~' refers to '$ISABELLE_HOME';

2490 * in locales, the "assumes" and "defines" parts may be omitted if

2491 empty;

2493 * new print_mode "xsymbols" for extended symbol support (e.g. genuine

2494 long arrows);

2496 * new print_mode "HTML";

2498 * new flag show_tags controls display of tags of theorems (which are

2499 basically just comments that may be attached by some tools);

2501 * Isamode 2.6 requires patch to accomodate change of Isabelle font

2502 mode and goal output format:

2504 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el

2505 244c244

2506 < (list (isa-getenv "ISABELLE") "-msymbols" logic-name)

2507 ---

2508 > (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)

2509 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el

2510 181c181

2511 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"

2512 ---

2513 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"

2515 * function bind_thms stores lists of theorems (cf. bind_thm);

2517 * new shorthand tactics ftac, eatac, datac, fatac;

2519 * qed (and friends) now accept "" as result name; in that case the

2520 theorem is not stored, but proper checks and presentation of the

2521 result still apply;

2523 * theorem database now also indexes constants "Trueprop", "all",

2524 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;

2527 *** HOL ***

2529 ** HOL arithmetic **

2531 * There are now decision procedures for linear arithmetic over nat and

2532 int:

2534 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',

2535 `+', `-', `Suc', `min', `max' and numerical constants; other subterms

2536 are treated as atomic; subformulae not involving type `nat' or `int'

2537 are ignored; quantified subformulae are ignored unless they are

2538 positive universal or negative existential. The tactic has to be

2539 invoked by hand and can be a little bit slow. In particular, the

2540 running time is exponential in the number of occurrences of `min' and

2541 `max', and `-' on `nat'.

2543 2. fast_arith_tac is a cut-down version of arith_tac: it only takes

2544 (negated) (in)equalities among the premises and the conclusion into

2545 account (i.e. no compound formulae) and does not know about `min' and

2546 `max', and `-' on `nat'. It is fast and is used automatically by the

2547 simplifier.

2549 NB: At the moment, these decision procedures do not cope with mixed

2550 nat/int formulae where the two parts interact, such as `m < n ==>

2551 int(m) < int(n)'.

2553 * HOL/Numeral provides a generic theory of numerals (encoded

2554 efficiently as bit strings); setup for types nat/int/real is in place;

2555 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than

2556 int, existing theories and proof scripts may require a few additional

2557 type constraints;

2559 * integer division and remainder can now be performed on constant

2560 arguments;

2562 * many properties of integer multiplication, division and remainder

2563 are now available;

2565 * An interface to the Stanford Validity Checker (SVC) is available through the

2566 tactic svc_tac. Propositional tautologies and theorems of linear arithmetic

2567 are proved automatically. SVC must be installed separately, and its results

2568 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any

2569 invocation of the underlying oracle). For SVC see

2570 http://verify.stanford.edu/SVC

2572 * IsaMakefile: the HOL-Real target now builds an actual image;

2575 ** HOL misc **

2577 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces

2578 (in Isabelle/Isar) -- by Gertrud Bauer;

2580 * HOL/BCV: generic model of bytecode verification, i.e. data-flow

2581 analysis for assembly languages with subtypes;

2583 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization

2584 -- avoids syntactic ambiguities and treats state, transition, and

2585 temporal levels more uniformly; introduces INCOMPATIBILITIES due to

2586 changed syntax and (many) tactics;

2588 * HOL/inductive: Now also handles more general introduction rules such

2589 as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity

2590 theorems are now maintained within the theory (maintained via the

2591 "mono" attribute);

2593 * HOL/datatype: Now also handles arbitrarily branching datatypes

2594 (using function types) such as

2596 datatype 'a tree = Atom 'a | Branch "nat => 'a tree"

2598 * HOL/record: record_simproc (part of the default simpset) takes care

2599 of selectors applied to updated records; record_split_tac is no longer

2600 part of the default claset; update_defs may now be removed from the

2601 simpset in many cases; COMPATIBILITY: old behavior achieved by

2603 claset_ref () := claset() addSWrapper record_split_wrapper;

2604 Delsimprocs [record_simproc]

2606 * HOL/typedef: fixed type inference for representing set; type

2607 arguments now have to occur explicitly on the rhs as type constraints;

2609 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem

2610 names rather than an ML expression;

2612 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be

2613 supplied later. Program schemes can be defined, such as

2614 "While B C s = (if B s then While B C (C s) else s)"

2615 where the well-founded relation can be chosen after B and C have been given.

2617 * HOL/List: the constructors of type list are now Nil and Cons;

2618 INCOMPATIBILITY: while [] and infix # syntax is still there, of

2619 course, ML tools referring to List.list.op # etc. have to be adapted;

2621 * HOL_quantifiers flag superseded by "HOL" print mode, which is

2622 disabled by default; run isabelle with option -m HOL to get back to

2623 the original Gordon/HOL-style output;

2625 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,

2626 ALL x<=y. P, EX x<y. P, EX x<=y. P;

2628 * HOL basic syntax simplified (more orthogonal): all variants of

2629 All/Ex now support plain / symbolic / HOL notation; plain syntax for

2630 Eps operator is provided as well: "SOME x. P[x]";

2632 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;

2634 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made

2635 thus available for user theories;

2637 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with

2638 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the

2639 time;

2641 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec

2642 several times and then mp;

2645 *** LK ***

2647 * the notation <<...>> is now available as a notation for sequences of

2648 formulas;

2650 * the simplifier is now installed

2652 * the axiom system has been generalized (thanks to Soren Heilmann)

2654 * the classical reasoner now has a default rule database

2657 *** ZF ***

2659 * new primrec section allows primitive recursive functions to be given

2660 directly (as in HOL) over datatypes and the natural numbers;

2662 * new tactics induct_tac and exhaust_tac for induction (or case

2663 analysis) over datatypes and the natural numbers;

2665 * the datatype declaration of type T now defines the recursor T_rec;

2667 * simplification automatically does freeness reasoning for datatype

2668 constructors;

2670 * automatic type-inference, with AddTCs command to insert new

2671 type-checking rules;

2673 * datatype introduction rules are now added as Safe Introduction rules

2674 to the claset;

2676 * the syntax "if P then x else y" is now available in addition to

2677 if(P,x,y);

2680 *** Internal programming interfaces ***

2682 * tuned simplifier trace output; new flag debug_simp;

2684 * structures Vartab / Termtab (instances of TableFun) offer efficient

2685 tables indexed by indexname_ord / term_ord (compatible with aconv);

2687 * AxClass.axclass_tac lost the theory argument;

2689 * tuned current_goals_markers semantics: begin / end goal avoids

2690 printing empty lines;

2692 * removed prs and prs_fn hook, which was broken because it did not

2693 include \n in its semantics, forcing writeln to add one

2694 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:

2695 string -> unit if you really want to output text without newline;

2697 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to

2698 plain output, interface builders may have to enable 'isabelle_font'

2699 mode to get Isabelle font glyphs as before;

2701 * refined token_translation interface; INCOMPATIBILITY: output length

2702 now of type real instead of int;

2704 * theory loader actions may be traced via new ThyInfo.add_hook

2705 interface (see src/Pure/Thy/thy_info.ML); example application: keep

2706 your own database of information attached to *whole* theories -- as

2707 opposed to intra-theory data slots offered via TheoryDataFun;

2709 * proper handling of dangling sort hypotheses (at last!);

2710 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing

2711 extra sort hypotheses that can be witnessed from the type signature;

2712 the force_strip_shyps flag is gone, any remaining shyps are simply

2713 left in the theorem (with a warning issued by strip_shyps_warning);

2717 New in Isabelle98-1 (October 1998)

2718 ----------------------------------

2720 *** Overview of INCOMPATIBILITIES (see below for more details) ***

2722 * several changes of automated proof tools;

2724 * HOL: major changes to the inductive and datatype packages, including

2725 some minor incompatibilities of theory syntax;

2727 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now

2728 called `inj_on';

2730 * HOL: removed duplicate thms in Arith:

2731 less_imp_add_less should be replaced by trans_less_add1

2732 le_imp_add_le should be replaced by trans_le_add1

2734 * HOL: unary minus is now overloaded (new type constraints may be

2735 required);

2737 * HOL and ZF: unary minus for integers is now #- instead of #~. In

2738 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is

2739 now taken as an integer constant.

2741 * Pure: ML function 'theory_of' renamed to 'theory';

2744 *** Proof tools ***

2746 * Simplifier:

2747 1. Asm_full_simp_tac is now more aggressive.

2748 1. It will sometimes reorient premises if that increases their power to

2749 simplify.

2750 2. It does no longer proceed strictly from left to right but may also

2751 rotate premises to achieve further simplification.

2752 For compatibility reasons there is now Asm_lr_simp_tac which is like the

2753 old Asm_full_simp_tac in that it does not rotate premises.

2754 2. The simplifier now knows a little bit about nat-arithmetic.

2756 * Classical reasoner: wrapper mechanism for the classical reasoner now

2757 allows for selected deletion of wrappers, by introduction of names for

2758 wrapper functionals. This implies that addbefore, addSbefore,

2759 addaltern, and addSaltern now take a pair (name, tactic) as argument,

2760 and that adding two tactics with the same name overwrites the first

2761 one (emitting a warning).

2762 type wrapper = (int -> tactic) -> (int -> tactic)

2763 setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by

2764 addWrapper, addSWrapper: claset * (string * wrapper) -> claset

2765 delWrapper, delSWrapper: claset * string -> claset

2766 getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;

2768 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE

2769 semantics; addbefore now affects only the unsafe part of step_tac

2770 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY

2771 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac

2772 by Force_tac;

2774 * Classical reasoner: setwrapper to setWrapper and compwrapper to

2775 compWrapper; added safe wrapper (and access functions for it);

2777 * HOL/split_all_tac is now much faster and fails if there is nothing

2778 to split. Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order

2779 and the names of the automatically generated variables have changed.

2780 split_all_tac has moved within claset() from unsafe wrappers to safe

2781 wrappers, which means that !!-bound variables are split much more

2782 aggressively, and safe_tac and clarify_tac now split such variables.

2783 If this splitting is not appropriate, use delSWrapper "split_all_tac".

2784 Note: the same holds for record_split_tac, which does the job of

2785 split_all_tac for record fields.

2787 * HOL/Simplifier: Rewrite rules for case distinctions can now be added

2788 permanently to the default simpset using Addsplits just like

2789 Addsimps. They can be removed via Delsplits just like

2790 Delsimps. Lower-case versions are also available.

2792 * HOL/Simplifier: The rule split_if is now part of the default

2793 simpset. This means that the simplifier will eliminate all occurrences

2794 of if-then-else in the conclusion of a goal. To prevent this, you can

2795 either remove split_if completely from the default simpset by

2796 `Delsplits [split_if]' or remove it in a specific call of the

2797 simplifier using `... delsplits [split_if]'. You can also add/delete

2798 other case splitting rules to/from the default simpset: every datatype

2799 generates suitable rules `split_t_case' and `split_t_case_asm' (where

2800 t is the name of the datatype).

2802 * Classical reasoner / Simplifier combination: new force_tac (and

2803 derivatives Force_tac, force) combines rewriting and classical

2804 reasoning (and whatever other tools) similarly to auto_tac, but is

2805 aimed to solve the given subgoal completely.

2808 *** General ***

2810 * new top-level commands `Goal' and `Goalw' that improve upon `goal'

2811 and `goalw': the theory is no longer needed as an explicit argument -

2812 the current theory context is used; assumptions are no longer returned

2813 at the ML-level unless one of them starts with ==> or !!; it is

2814 recommended to convert to these new commands using isatool fixgoal

2815 (backup your sources first!);

2817 * new top-level commands 'thm' and 'thms' for retrieving theorems from

2818 the current theory context, and 'theory' to lookup stored theories;

2820 * new theory section 'locale' for declaring constants, assumptions and

2821 definitions that have local scope;

2823 * new theory section 'nonterminals' for purely syntactic types;

2825 * new theory section 'setup' for generic ML setup functions

2826 (e.g. package initialization);

2828 * the distribution now includes Isabelle icons: see

2829 lib/logo/isabelle-{small,tiny}.xpm;

2831 * isatool install - install binaries with absolute references to

2832 ISABELLE_HOME/bin;

2834 * isatool logo -- create instances of the Isabelle logo (as EPS);

2836 * print mode 'emacs' reserved for Isamode;

2838 * support multiple print (ast) translations per constant name;

2840 * theorems involving oracles are now printed with a suffixed [!];

2843 *** HOL ***

2845 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');

2847 * HOL/inductive package reorganized and improved: now supports mutual

2848 definitions such as

2850 inductive EVEN ODD

2851 intrs

2852 null "0 : EVEN"

2853 oddI "n : EVEN ==> Suc n : ODD"

2854 evenI "n : ODD ==> Suc n : EVEN"

2856 new theorem list "elims" contains an elimination rule for each of the

2857 recursive sets; inductive definitions now handle disjunctive premises

2858 correctly (also ZF);

2860 INCOMPATIBILITIES: requires Inductive as an ancestor; component

2861 "mutual_induct" no longer exists - the induction rule is always

2862 contained in "induct";

2865 * HOL/datatype package re-implemented and greatly improved: now

2866 supports mutually recursive datatypes such as

2868 datatype

2869 'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)

2870 | SUM ('a aexp) ('a aexp)

2871 | DIFF ('a aexp) ('a aexp)

2872 | NUM 'a

2873 and

2874 'a bexp = LESS ('a aexp) ('a aexp)

2875 | AND ('a bexp) ('a bexp)

2876 | OR ('a bexp) ('a bexp)

2878 as well as indirectly recursive datatypes such as

2880 datatype

2881 ('a, 'b) term = Var 'a

2882 | App 'b ((('a, 'b) term) list)

2884 The new tactic mutual_induct_tac [<var_1>, ..., <var_n>] i performs

2885 induction on mutually / indirectly recursive datatypes.

2887 Primrec equations are now stored in theory and can be accessed via

2888 <function_name>.simps.

2890 INCOMPATIBILITIES:

2892 - Theories using datatypes must now have theory Datatype as an

2893 ancestor.

2894 - The specific <typename>.induct_tac no longer exists - use the

2895 generic induct_tac instead.

2896 - natE has been renamed to nat.exhaust - use exhaust_tac

2897 instead of res_inst_tac ... natE. Note that the variable

2898 names in nat.exhaust differ from the names in natE, this

2899 may cause some "fragile" proofs to fail.

2900 - The theorems split_<typename>_case and split_<typename>_case_asm

2901 have been renamed to <typename>.split and <typename>.split_asm.

2902 - Since default sorts of type variables are now handled correctly,

2903 some datatype definitions may have to be annotated with explicit

2904 sort constraints.

2905 - Primrec definitions no longer require function name and type

2906 of recursive argument.

2908 Consider using isatool fixdatatype to adapt your theories and proof

2909 scripts to the new package (backup your sources first!).

2912 * HOL/record package: considerably improved implementation; now

2913 includes concrete syntax for record types, terms, updates; theorems

2914 for surjective pairing and splitting !!-bound record variables; proof

2915 support is as follows:

2917 1) standard conversions (selectors or updates applied to record

2918 constructor terms) are part of the standard simpset;

2920 2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are

2921 made part of standard simpset and claset via addIffs;

2923 3) a tactic for record field splitting (record_split_tac) is part of

2924 the standard claset (addSWrapper);

2926 To get a better idea about these rules you may retrieve them via

2927 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is

2928 the name of your record type.

2930 The split tactic 3) conceptually simplifies by the following rule:

2932 "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"

2934 Thus any record variable that is bound by meta-all will automatically

2935 blow up into some record constructor term, consequently the

2936 simplifications of 1), 2) apply. Thus force_tac, auto_tac etc. shall

2937 solve record problems automatically.

2940 * reorganized the main HOL image: HOL/Integ and String loaded by

2941 default; theory Main includes everything;

2943 * automatic simplification of integer sums and comparisons, using cancellation;

2945 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;

2947 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;

2949 * many new identities for unions, intersections, set difference, etc.;

2951 * expand_if, expand_split, expand_sum_case and expand_nat_case are now

2952 called split_if, split_split, split_sum_case and split_nat_case (to go

2953 with add/delsplits);

2955 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting

2956 (?x::unit) = (); this is made part of the default simpset, which COULD

2957 MAKE EXISTING PROOFS FAIL under rare circumstances (consider

2958 'Delsimprocs [unit_eq_proc];' as last resort); also note that

2959 unit_abs_eta_conv is added in order to counter the effect of

2960 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by

2961 %u.f();

2963 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which

2964 makes more sense);

2966 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;

2967 It and 'sym RS equals0D' are now in the default claset, giving automatic

2968 disjointness reasoning but breaking a few old proofs.

2970 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1

2971 to 'converse' from 'inverse' (for compatibility with ZF and some

2972 literature);

2974 * HOL/recdef can now declare non-recursive functions, with {} supplied as

2975 the well-founded relation;

2977 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of

2978 Compl A. The "Compl" syntax remains available as input syntax for this

2979 release ONLY.

2981 * HOL/Update: new theory of function updates:

2982 f(a:=b) == %x. if x=a then b else f x

2983 may also be iterated as in f(a:=b,c:=d,...);

2985 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;

2987 * HOL/List:

2988 - new function list_update written xs[i:=v] that updates the i-th

2989 list position. May also be iterated as in xs[i:=a,j:=b,...].

2990 - new function `upt' written [i..j(] which generates the list

2991 [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper

2992 bound write [i..j], which is a shorthand for [i..j+1(].

2993 - new lexicographic orderings and corresponding wellfoundedness theorems.

2995 * HOL/Arith:

2996 - removed 'pred' (predecessor) function;

2997 - generalized some theorems about n-1;

2998 - many new laws about "div" and "mod";

2999 - new laws about greatest common divisors (see theory ex/Primes);

3001 * HOL/Relation: renamed the relational operator r^-1 "converse"

3002 instead of "inverse";

3004 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness

3005 of the multiset ordering;

3007 * directory HOL/Real: a construction of the reals using Dedekind cuts

3008 (not included by default);

3010 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;

3012 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted

3013 programs, i.e. different program variables may have different types.

3015 * calling (stac rew i) now fails if "rew" has no effect on the goal

3016 [previously, this check worked only if the rewrite rule was unconditional]

3017 Now rew can involve either definitions or equalities (either == or =).

3020 *** ZF ***

3022 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains

3023 only the theorems proved on ZF.ML;

3025 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;

3026 It and 'sym RS equals0D' are now in the default claset, giving automatic

3027 disjointness reasoning but breaking a few old proofs.

3029 * ZF/Update: new theory of function updates

3030 with default rewrite rule f(x:=y) ` z = if(z=x, y, f`z)

3031 may also be iterated as in f(a:=b,c:=d,...);

3033 * in let x=t in u(x), neither t nor u(x) has to be an FOL term.

3035 * calling (stac rew i) now fails if "rew" has no effect on the goal

3036 [previously, this check worked only if the rewrite rule was unconditional]

3037 Now rew can involve either definitions or equalities (either == or =).

3039 * case_tac provided for compatibility with HOL

3040 (like the old excluded_middle_tac, but with subgoals swapped)

3043 *** Internal programming interfaces ***

3045 * Pure: several new basic modules made available for general use, see

3046 also src/Pure/README;

3048 * improved the theory data mechanism to support encapsulation (data

3049 kind name replaced by private Object.kind, acting as authorization

3050 key); new type-safe user interface via functor TheoryDataFun; generic

3051 print_data function becomes basically useless;

3053 * removed global_names compatibility flag -- all theory declarations

3054 are qualified by default;

3056 * module Pure/Syntax now offers quote / antiquote translation

3057 functions (useful for Hoare logic etc. with implicit dependencies);

3058 see HOL/ex/Antiquote for an example use;

3060 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->

3061 cterm -> thm;

3063 * new tactical CHANGED_GOAL for checking that a tactic modifies a

3064 subgoal;

3066 * Display.print_goals function moved to Locale.print_goals;

3068 * standard print function for goals supports current_goals_markers

3069 variable for marking begin of proof, end of proof, start of goal; the

3070 default is ("", "", ""); setting current_goals_markers := ("<proof>",

3071 "</proof>", "<goal>") causes SGML like tagged proof state printing,

3072 for example;

3076 New in Isabelle98 (January 1998)

3077 --------------------------------

3079 *** Overview of INCOMPATIBILITIES (see below for more details) ***

3081 * changed lexical syntax of terms / types: dots made part of long

3082 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";

3084 * simpset (and claset) reference variable replaced by functions

3085 simpset / simpset_ref;

3087 * no longer supports theory aliases (via merge) and non-trivial

3088 implicit merge of thms' signatures;

3090 * most internal names of constants changed due to qualified names;

3092 * changed Pure/Sequence interface (see Pure/seq.ML);

3095 *** General Changes ***

3097 * hierachically structured name spaces (for consts, types, axms, thms

3098 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of

3099 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:

3100 isatool fixdots ensures space after dots (e.g. "%x. x"); set

3101 long_names for fully qualified output names; NOTE: ML programs

3102 (special tactics, packages etc.) referring to internal names may have

3103 to be adapted to cope with fully qualified names; in case of severe

3104 backward campatibility problems try setting 'global_names' at compile

3105 time to have enrything declared within a flat name space; one may also

3106 fine tune name declarations in theories via the 'global' and 'local'

3107 section;

3109 * reimplemented the implicit simpset and claset using the new anytype

3110 data filed in signatures; references simpset:simpset ref etc. are

3111 replaced by functions simpset:unit->simpset and

3112 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp

3113 to patch your ML files accordingly;

3115 * HTML output now includes theory graph data for display with Java

3116 applet or isatool browser; data generated automatically via isatool

3117 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);

3119 * defs may now be conditional; improved rewrite_goals_tac to handle

3120 conditional equations;

3122 * defs now admits additional type arguments, using TYPE('a) syntax;

3124 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always

3125 creates a new theory node; implicit merge of thms' signatures is

3126 restricted to 'trivial' ones; COMPATIBILITY: one may have to use

3127 transfer:theory->thm->thm in (rare) cases;

3129 * improved handling of draft signatures / theories; draft thms (and

3130 ctyps, cterms) are automatically promoted to real ones;

3132 * slightly changed interfaces for oracles: admit many per theory, named

3133 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;

3135 * print_goals: optional output of const types (set show_consts and

3136 show_types);

3138 * improved output of warnings (###) and errors (***);

3140 * subgoal_tac displays a warning if the new subgoal has type variables;

3142 * removed old README and Makefiles;

3144 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;

3146 * removed obsolete init_pps and init_database;

3148 * deleted the obsolete tactical STATE, which was declared by

3149 fun STATE tacfun st = tacfun st st;

3151 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~

3152 (which abbreviates $HOME);

3154 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:

3155 use isatool fixseq to adapt your ML programs (this works for fully

3156 qualified references to the Sequence structure only!);

3158 * use_thy no longer requires writable current directory; it always

3159 reloads .ML *and* .thy file, if either one is out of date;

3162 *** Classical Reasoner ***

3164 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new

3165 tactics that use classical reasoning to simplify a subgoal without

3166 splitting it into several subgoals;

3168 * Safe_tac: like safe_tac but uses the default claset;

3171 *** Simplifier ***

3173 * added simplification meta rules:

3174 (asm_)(full_)simplify: simpset -> thm -> thm;

3176 * simplifier.ML no longer part of Pure -- has to be loaded by object

3177 logics (again);

3179 * added prems argument to simplification procedures;

3181 * HOL, FOL, ZF: added infix function `addsplits':

3182 instead of `<simpset> setloop (split_tac <thms>)'

3183 you can simply write `<simpset> addsplits <thms>'

3186 *** Syntax ***

3188 * TYPE('a) syntax for type reflection terms;

3190 * no longer handles consts with name "" -- declare as 'syntax' instead;

3192 * pretty printer: changed order of mixfix annotation preference (again!);

3194 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;

3197 *** HOL ***

3199 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.

3200 with `addloop' of the simplifier to faciliate case splitting in premises.

3202 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;

3204 * HOL/Auth: new protocol proofs including some for the Internet

3205 protocol TLS;

3207 * HOL/Map: new theory of `maps' a la VDM;

3209 * HOL/simplifier: simplification procedures nat_cancel_sums for

3210 cancelling out common nat summands from =, <, <= (in)equalities, or

3211 differences; simplification procedures nat_cancel_factor for

3212 cancelling common factor from =, <, <= (in)equalities over natural

3213 sums; nat_cancel contains both kinds of procedures, it is installed by

3214 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;

3216 * HOL/simplifier: terms of the form

3217 `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)' (or t=x)

3218 are rewritten to

3219 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',

3220 and those of the form

3221 `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)' (or t=x)

3222 are rewritten to

3223 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',

3225 * HOL/datatype

3226 Each datatype `t' now comes with a theorem `split_t_case' of the form

3228 P(t_case f1 ... fn x) =

3229 ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &

3230 ...

3231 (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))

3232 )

3234 and a theorem `split_t_case_asm' of the form

3236 P(t_case f1 ... fn x) =

3237 ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |

3238 ...

3239 (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))

3240 )

3241 which can be added to a simpset via `addsplits'. The existing theorems

3242 expand_list_case and expand_option_case have been renamed to

3243 split_list_case and split_option_case.

3245 * HOL/Arithmetic:

3246 - `pred n' is automatically converted to `n-1'.

3247 Users are strongly encouraged not to use `pred' any longer,

3248 because it will disappear altogether at some point.

3249 - Users are strongly encouraged to write "0 < n" rather than

3250 "n ~= 0". Theorems and proof tools have been modified towards this

3251 `standard'.

3253 * HOL/Lists:

3254 the function "set_of_list" has been renamed "set" (and its theorems too);

3255 the function "nth" now takes its arguments in the reverse order and

3256 has acquired the infix notation "!" as in "xs!n".

3258 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};

3260 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its

3261 specialist theorems (like UN1_I) are gone. Similarly for (INT x.B x);

3263 * HOL/record: extensible records with schematic structural subtyping

3264 (single inheritance); EXPERIMENTAL version demonstrating the encoding,

3265 still lacks various theorems and concrete record syntax;

3268 *** HOLCF ***

3270 * removed "axioms" and "generated by" sections;

3272 * replaced "ops" section by extended "consts" section, which is capable of

3273 handling the continuous function space "->" directly;

3275 * domain package:

3276 . proves theorems immediately and stores them in the theory,

3277 . creates hierachical name space,

3278 . now uses normal mixfix annotations (instead of cinfix...),

3279 . minor changes to some names and values (for consistency),

3280 . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,

3281 . separator between mutual domain defs: changed "," to "and",

3282 . improved handling of sort constraints; now they have to

3283 appear on the left-hand side of the equations only;

3285 * fixed LAM <x,y,zs>.b syntax;

3287 * added extended adm_tac to simplifier in HOLCF -- can now discharge

3288 adm (%x. P (t x)), where P is chainfinite and t continuous;

3291 *** FOL and ZF ***

3293 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.

3294 with `addloop' of the simplifier to faciliate case splitting in premises.

3296 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as

3297 in HOL, they strip ALL and --> from proved theorems;

3301 New in Isabelle94-8 (May 1997)

3302 ------------------------------

3304 *** General Changes ***

3306 * new utilities to build / run / maintain Isabelle etc. (in parts

3307 still somewhat experimental); old Makefiles etc. still functional;

3309 * new 'Isabelle System Manual';

3311 * INSTALL text, together with ./configure and ./build scripts;

3313 * reimplemented type inference for greater efficiency, better error

3314 messages and clean internal interface;

3316 * prlim command for dealing with lots of subgoals (an easier way of

3317 setting goals_limit);

3320 *** Syntax ***

3322 * supports alternative (named) syntax tables (parser and pretty

3323 printer); internal interface is provided by add_modesyntax(_i);

3325 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to

3326 be used in conjunction with the Isabelle symbol font; uses the

3327 "symbols" syntax table;

3329 * added token_translation interface (may translate name tokens in

3330 arbitrary ways, dependent on their type (free, bound, tfree, ...) and

3331 the current print_mode); IMPORTANT: user print translation functions

3332 are responsible for marking newly introduced bounds

3333 (Syntax.mark_boundT);

3335 * token translations for modes "xterm" and "xterm_color" that display

3336 names in bold, underline etc. or colors (which requires a color

3337 version of xterm);

3339 * infixes may now be declared with names independent of their syntax;

3341 * added typed_print_translation (like print_translation, but may

3342 access type of constant);

3345 *** Classical Reasoner ***

3347 Blast_tac: a new tactic! It is often more powerful than fast_tac, but has

3348 some limitations. Blast_tac...

3349 + ignores addss, addbefore, addafter; this restriction is intrinsic

3350 + ignores elimination rules that don't have the correct format

3351 (the conclusion MUST be a formula variable)

3352 + ignores types, which can make HOL proofs fail

3353 + rules must not require higher-order unification, e.g. apply_type in ZF

3354 [message "Function Var's argument not a bound variable" relates to this]

3355 + its proof strategy is more general but can actually be slower

3357 * substitution with equality assumptions no longer permutes other

3358 assumptions;

3360 * minor changes in semantics of addafter (now called addaltern); renamed

3361 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper

3362 (and access functions for it);

3364 * improved combination of classical reasoner and simplifier:

3365 + functions for handling clasimpsets

3366 + improvement of addss: now the simplifier is called _after_ the

3367 safe steps.

3368 + safe variant of addss called addSss: uses safe simplifications

3369 _during_ the safe steps. It is more complete as it allows multiple

3370 instantiations of unknowns (e.g. with slow_tac).

3372 *** Simplifier ***

3374 * added interface for simplification procedures (functions that

3375 produce *proven* rewrite rules on the fly, depending on current

3376 redex);

3378 * ordering on terms as parameter (used for ordered rewriting);

3380 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;

3382 * the solver is now split into a safe and an unsafe part.

3383 This should be invisible for the normal user, except that the

3384 functions setsolver and addsolver have been renamed to setSolver and

3385 addSolver; added safe_asm_full_simp_tac;

3388 *** HOL ***

3390 * a generic induction tactic `induct_tac' which works for all datatypes and

3391 also for type `nat';

3393 * a generic case distinction tactic `exhaust_tac' which works for all

3394 datatypes and also for type `nat';

3396 * each datatype comes with a function `size';

3398 * patterns in case expressions allow tuple patterns as arguments to

3399 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';

3401 * primrec now also works with type nat;

3403 * recdef: a new declaration form, allows general recursive functions to be

3404 defined in theory files. See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.

3406 * the constant for negation has been renamed from "not" to "Not" to

3407 harmonize with FOL, ZF, LK, etc.;

3409 * HOL/ex/LFilter theory of a corecursive "filter" functional for

3410 infinite lists;

3412 * HOL/Modelcheck demonstrates invocation of model checker oracle;

3414 * HOL/ex/Ring.thy declares cring_simp, which solves equational

3415 problems in commutative rings, using axiomatic type classes for + and *;

3417 * more examples in HOL/MiniML and HOL/Auth;

3419 * more default rewrite rules for quantifiers, union/intersection;

3421 * a new constant `arbitrary == @x.False';

3423 * HOLCF/IOA replaces old HOL/IOA;

3425 * HOLCF changes: derived all rules and arities

3426 + axiomatic type classes instead of classes

3427 + typedef instead of faking type definitions

3428 + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.

3429 + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po

3430 + eliminated the types void, one, tr

3431 + use unit lift and bool lift (with translations) instead of one and tr

3432 + eliminated blift from Lift3.thy (use Def instead of blift)

3433 all eliminated rules are derived as theorems --> no visible changes ;

3436 *** ZF ***

3438 * ZF now has Fast_tac, Simp_tac and Auto_tac. Union_iff is a now a default

3439 rewrite rule; this may affect some proofs. eq_cs is gone but can be put back

3440 as ZF_cs addSIs [equalityI];

3444 New in Isabelle94-7 (November 96)

3445 ---------------------------------

3447 * allowing negative levels (as offsets) in prlev and choplev;

3449 * super-linear speedup for large simplifications;

3451 * FOL, ZF and HOL now use miniscoping: rewriting pushes

3452 quantifications in as far as possible (COULD MAKE EXISTING PROOFS

3453 FAIL); can suppress it using the command Delsimps (ex_simps @

3454 all_simps); De Morgan laws are also now included, by default;

3456 * improved printing of ==> : ~:

3458 * new object-logic "Sequents" adds linear logic, while replacing LK

3459 and Modal (thanks to Sara Kalvala);

3461 * HOL/Auth: correctness proofs for authentication protocols;

3463 * HOL: new auto_tac combines rewriting and classical reasoning (many

3464 examples on HOL/Auth);

3466 * HOL: new command AddIffs for declaring theorems of the form P=Q to

3467 the rewriter and classical reasoner simultaneously;

3469 * function uresult no longer returns theorems in "standard" format;

3470 regain previous version by: val uresult = standard o uresult;

3474 New in Isabelle94-6

3475 -------------------

3477 * oracles -- these establish an interface between Isabelle and trusted

3478 external reasoners, which may deliver results as theorems;

3480 * proof objects (in particular record all uses of oracles);

3482 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;

3484 * "constdefs" section in theory files;

3486 * "primrec" section (HOL) no longer requires names;

3488 * internal type "tactic" now simply "thm -> thm Sequence.seq";

3492 New in Isabelle94-5

3493 -------------------

3495 * reduced space requirements;

3497 * automatic HTML generation from theories;

3499 * theory files no longer require "..." (quotes) around most types;

3501 * new examples, including two proofs of the Church-Rosser theorem;

3503 * non-curried (1994) version of HOL is no longer distributed;

3507 New in Isabelle94-4

3508 -------------------

3510 * greatly reduced space requirements;

3512 * theory files (.thy) no longer require \...\ escapes at line breaks;

3514 * searchable theorem database (see the section "Retrieving theorems" on

3515 page 8 of the Reference Manual);

3517 * new examples, including Grabczewski's monumental case study of the

3518 Axiom of Choice;

3520 * The previous version of HOL renamed to Old_HOL;

3522 * The new version of HOL (previously called CHOL) uses a curried syntax

3523 for functions. Application looks like f a b instead of f(a,b);

3525 * Mutually recursive inductive definitions finally work in HOL;

3527 * In ZF, pattern-matching on tuples is now available in all abstractions and

3528 translates to the operator "split";

3532 New in Isabelle94-3

3533 -------------------

3535 * new infix operator, addss, allowing the classical reasoner to

3536 perform simplification at each step of its search. Example:

3537 fast_tac (cs addss ss)

3539 * a new logic, CHOL, the same as HOL, but with a curried syntax

3540 for functions. Application looks like f a b instead of f(a,b). Also pairs

3541 look like (a,b) instead of <a,b>;

3543 * PLEASE NOTE: CHOL will eventually replace HOL!

3545 * In CHOL, pattern-matching on tuples is now available in all abstractions.

3546 It translates to the operator "split". A new theory of integers is available;

3548 * In ZF, integer numerals now denote two's-complement binary integers.

3549 Arithmetic operations can be performed by rewriting. See ZF/ex/Bin.ML;

3551 * Many new examples: I/O automata, Church-Rosser theorem, equivalents

3552 of the Axiom of Choice;

3556 New in Isabelle94-2

3557 -------------------

3559 * Significantly faster resolution;

3561 * the different sections in a .thy file can now be mixed and repeated

3562 freely;

3564 * Database of theorems for FOL, HOL and ZF. New

3565 commands including qed, qed_goal and bind_thm store theorems in the database.

3567 * Simple database queries: return a named theorem (get_thm) or all theorems of

3568 a given theory (thms_of), or find out what theory a theorem was proved in

3569 (theory_of_thm);

3571 * Bugs fixed in the inductive definition and datatype packages;

3573 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs

3574 and HOL_dup_cs obsolete;

3576 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1

3577 have been removed;

3579 * Simpler definition of function space in ZF;

3581 * new results about cardinal and ordinal arithmetic in ZF;

3583 * 'subtype' facility in HOL for introducing new types as subsets of existing

3584 types;

3587 $Id$