text:
|Thu Dec 07 00:42:04 2006 +0100 (2006-12-07)
|changeset 21687
|parent 21647
|child 21717
1 Isabelle NEWS -- history user-relevant changes
2 ==============================================
4 New in this Isabelle version
5 ----------------------------
7 *** General ***
9 * Theory syntax: the header format ``theory A = B + C:'' has been
10 discontinued in favour of ``theory A imports B C begin''. Use isatool
11 fixheaders to convert existing theory files. INCOMPATIBILITY.
13 * Theory syntax: the old non-Isar theory file format has been
14 discontinued altogether. Note that ML proof scripts may still be used
15 with Isar theories; migration is usually quite simple with the ML
16 function use_legacy_bindings. INCOMPATIBILITY.
18 * Theory syntax: some popular names (e.g. "class", "if", "fun") are
19 now keywords. INCOMPATIBILITY, use double quotes.
21 * Legacy goal package: reduced interface to the bare minimum required
22 to keep existing proof scripts running. Most other user-level
23 functions are now part of the OldGoals structure, which is *not* open
24 by default (consider isatool expandshort before open OldGoals).
25 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
26 these tend to cause confusion about the actual goal (!) context being
27 used here, which is not necessarily the same as the_context().
29 * Command 'find_theorems': support "*" wildcard in "name:" criterion.
31 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
32 by default, which means that "prems" (and also "fixed variables") are
33 suppressed from proof state output. Note that the ProofGeneral
34 settings mechanism allows to change and save options persistently, but
35 older versions of Isabelle will fail to start up if a negative prems
36 limit is imposed.
38 * Local theory targets may be specified by non-nested blocks of
39 ``context/locale/class ... begin'' followed by ``end''. The body may
40 contain definitions, theorems etc., including any derived mechanism
41 that has been implemented on top of these primitives. This concept
42 generalizes the existing ``theorem (in ...)'' towards more versatility
43 and scalability.
46 *** Document preparation ***
48 * Added antiquotation @{theory name} which prints the name $A$, after
49 checking that it refers to a valid ancestor theory in the current
50 context.
52 * Added antiquotations @{ML_type text} and @{ML_struct text} which
53 check the given source text as ML type/structure, printing verbatim.
56 *** Pure ***
58 * class_package.ML offers a combination of axclasses and locales to
59 achieve Haskell-like type classes in Isabelle. See
60 HOL/ex/Classpackage.thy for examples.
62 * Yet another code generator framework allows to generate executable
63 code for ML and Haskell (including "class"es). A short usage sketch:
65 internal compilation:
66 code_gen <list of constants (term syntax)> (SML #)
67 writing SML code to a file:
68 code_gen <list of constants (term syntax)> (SML <filename>)
69 writing Haskell code to a bunch of files:
70 code_gen <list of constants (term syntax)> (Haskell <filename>)
72 Reasonable default setup of framework in HOL/Main.
74 See HOL/ex/Code*.thy for examples.
76 Theorem attributs for selecting and transforming function equations theorems:
78 [code fun]: select a theorem as function equation for a specific constant
79 [code nofun]: deselect a theorem as function equation for a specific constant
80 [code inline]: select an equation theorem for unfolding (inlining) in place
81 [code noinline]: deselect an equation theorem for unfolding (inlining) in place
83 User-defined serializations (target in {SML, Haskell}):
85 code_const <and-list of constants (term syntax)>
86 {(target) <and-list of const target syntax>}+
88 code_type <and-list of type constructors>
89 {(target) <and-list of type target syntax>}+
91 code_instance <and-list of instances>
92 {(target)}+
93 where instance ::= <type constructor> :: <class>
95 code_class <and_list of classes>
96 {(target) <and-list of class target syntax>}+
97 where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
99 For code_instance and code_class, target SML is silently ignored.
101 See HOL theories and HOL/ex/Code*.thy for usage examples. Doc/Isar/Advanced/Codegen/
102 provides a tutorial.
104 * Command 'no_translations' removes translation rules from theory
105 syntax.
107 * Overloaded definitions are now actually checked for acyclic
108 dependencies. The overloading scheme is slightly more general than
109 that of Haskell98, although Isabelle does not demand an exact
110 correspondence to type class and instance declarations.
111 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
112 exotic versions of overloading -- at the discretion of the user!
114 Polymorphic constants are represented via type arguments, i.e. the
115 instantiation that matches an instance against the most general
116 declaration given in the signature. For example, with the declaration
117 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
118 as c(nat). Overloading is essentially simultaneous structural
119 recursion over such type arguments. Incomplete specification patterns
120 impose global constraints on all occurrences, e.g. c('a * 'a) on the
121 LHS means that more general c('a * 'b) will be disallowed on any RHS.
122 Command 'print_theory' outputs the normalized system of recursive
123 equations, see section "definitions".
125 * Isar: improper proof element 'guess' is like 'obtain', but derives
126 the obtained context from the course of reasoning! For example:
128 assume "EX x y. A x & B y" -- "any previous fact"
129 then guess x and y by clarify
131 This technique is potentially adventurous, depending on the facts and
132 proof tools being involved here.
134 * Isar: known facts from the proof context may be specified as literal
135 propositions, using ASCII back-quote syntax. This works wherever
136 named facts used to be allowed so far, in proof commands, proof
137 methods, attributes etc. Literal facts are retrieved from the context
138 according to unification of type and term parameters. For example,
139 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
140 theorems in the current context, then these are valid literal facts:
141 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
143 There is also a proof method "fact" which does the same composition
144 for explicit goal states, e.g. the following proof texts coincide with
145 certain special cases of literal facts:
147 have "A" by fact == note `A`
148 have "A ==> B" by fact == note `A ==> B`
149 have "!!x. P x ==> Q x" by fact == note `!!x. P x ==> Q x`
150 have "P a ==> Q a" by fact == note `P a ==> Q a`
152 * Isar: ":" (colon) is no longer a symbolic identifier character in
153 outer syntax. Thus symbolic identifiers may be used without
154 additional white space in declarations like this: ``assume *: A''.
156 * Isar: 'print_facts' prints all local facts of the current context,
157 both named and unnamed ones.
159 * Isar: 'def' now admits simultaneous definitions, e.g.:
161 def x == "t" and y == "u"
163 * Isar: added command 'unfolding', which is structurally similar to
164 'using', but affects both the goal state and facts by unfolding given
165 rewrite rules. Thus many occurrences of the 'unfold' method or
166 'unfolded' attribute may be replaced by first-class proof text.
168 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
169 and command 'unfolding' now all support object-level equalities
170 (potentially conditional). The underlying notion of rewrite rule is
171 analogous to the 'rule_format' attribute, but *not* that of the
172 Simplifier (which is usually more generous).
174 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
175 method expression within a sandbox consisting of the first N
176 sub-goals, which need to exist. For example, ``simp_all [3]''
177 simplifies the first three sub-goals, while (rule foo, simp_all)[]
178 simplifies all new goals that emerge from applying rule foo to the
179 originally first one.
181 * Isar: schematic goals are no longer restricted to higher-order
182 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
183 expected.
185 * Isar: the conclusion of a long theorem statement is now either
186 'shows' (a simultaneous conjunction, as before), or 'obtains'
187 (essentially a disjunction of cases with local parameters and
188 assumptions). The latter allows to express general elimination rules
189 adequately; in this notation common elimination rules look like this:
191 lemma exE: -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
192 assumes "EX x. P x"
193 obtains x where "P x"
195 lemma conjE: -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
196 assumes "A & B"
197 obtains A and B
199 lemma disjE: -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
200 assumes "A | B"
201 obtains
205 The subsequent classical rules even refer to the formal "thesis"
206 explicitly:
208 lemma classical: -- "(~ thesis ==> thesis) ==> thesis"
209 obtains "~ thesis"
211 lemma Peirce's_Law: -- "((thesis ==> something) ==> thesis) ==> thesis"
212 obtains "thesis ==> something"
214 The actual proof of an 'obtains' statement is analogous to that of the
215 Isar proof element 'obtain', only that there may be several cases.
216 Optional case names may be specified in parentheses; these will be
217 available both in the present proof and as annotations in the
218 resulting rule, for later use with the 'cases' method (cf. attribute
219 case_names).
221 * Isar: the assumptions of a long theorem statement are available as
222 "assms" fact in the proof context. This is more appropriate than the
223 (historical) "prems", which refers to all assumptions of the current
224 context, including those from the target locale, proof body etc.
226 * Isar: 'print_statement' prints theorems from the current theory or
227 proof context in long statement form, according to the syntax of a
228 top-level lemma.
230 * Isar: 'obtain' takes an optional case name for the local context
231 introduction rule (default "that").
233 * Isar: removed obsolete 'concl is' patterns. INCOMPATIBILITY, use
234 explicit (is "_ ==> ?foo") in the rare cases where this still happens
235 to occur.
237 * Pure: syntax "CONST name" produces a fully internalized constant
238 according to the current context. This is particularly useful for
239 syntax translations that should refer to internal constant
240 representations independently of name spaces.
242 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
243 instead of "FOO ". This allows multiple binder declarations to coexist
244 in the same context. INCOMPATIBILITY.
246 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
247 primitive that also works in a locale context (both for constants and
248 fixed variables). Type declaration and internal syntactic
249 representation of given constants retrieved from the context.
251 * Isar/locales: new derived specification elements 'axiomatization',
252 'definition', 'abbreviation', which support type-inference, admit
253 object-level specifications (equality, equivalence). See also the
254 isar-ref manual. Examples:
256 axiomatization
257 eq (infix "===" 50) where
258 eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
260 definition "f x y = x + y + 1"
261 definition g where "g x = f x x"
263 abbreviation
264 neq (infix "=!=" 50) where
265 "x =!= y == ~ (x === y)"
267 These specifications may be also used in a locale context. Then the
268 constants being introduced depend on certain fixed parameters, and the
269 constant name is qualified by the locale base name. An internal
270 abbreviation takes care for convenient input and output, making the
271 parameters implicit and using the original short name. See also
272 HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
273 entities from a monomorphic theory.
275 Presently, abbreviations are only available 'in' a target locale, but
276 not inherited by general import expressions. Also note that
277 'abbreviation' may be used as a type-safe replacement for 'syntax' +
278 'translations' in common applications.
280 Concrete syntax is attached to specified constants in internal form,
281 independently of name spaces. The parse tree representation is
282 slightly different -- use 'notation' instead of raw 'syntax', and
283 'translations' with explicit "CONST" markup to accommodate this.
285 * Isar/locales: improved parameter handling:
286 - use of locales "var" and "struct" no longer necessary;
287 - parameter renamings are no longer required to be injective.
288 This enables, for example, to define a locale for endomorphisms thus:
289 locale endom = homom mult mult h.
291 * Isar/locales: changed the way locales with predicates are defined.
292 Instead of accumulating the specification, the imported expression is
293 now an interpretation.
294 INCOMPATIBILITY: different normal form of locale expressions.
295 In particular, in interpretations of locales with predicates,
296 goals repesenting already interpreted fragments are not removed
297 automatically. Use methods `intro_locales' and `unfold_locales'; see below.
299 * Isar/locales: new methods `intro_locales' and `unfold_locales' provide
300 backward reasoning on locales predicates. The methods are aware of
301 interpretations and discharge corresponding goals. `intro_locales' is
302 less aggressive then `unfold_locales' and does not unfold predicates to
303 assumptions.
305 * Isar/locales: the order in which locale fragments are accumulated
306 has changed. This enables to override declarations from fragments
307 due to interpretations -- for example, unwanted simp rules.
309 * Provers/induct: improved internal context management to support
310 local fixes and defines on-the-fly. Thus explicit meta-level
311 connectives !! and ==> are rarely required anymore in inductive goals
312 (using object-logic connectives for this purpose has been long
313 obsolete anyway). The subsequent proof patterns illustrate advanced
314 techniques of natural induction; general datatypes and inductive sets
315 work analogously (see also src/HOL/Lambda for realistic examples).
317 (1) This is how to ``strengthen'' an inductive goal wrt. certain
318 parameters:
320 lemma
321 fixes n :: nat and x :: 'a
322 assumes a: "A n x"
323 shows "P n x"
324 using a -- {* make induct insert fact a *}
325 proof (induct n arbitrary: x) -- {* generalize goal to "!!x. A n x ==> P n x" *}
326 case 0
327 show ?case sorry
328 next
329 case (Suc n)
330 note `!!x. A n x ==> P n x` -- {* induction hypothesis, according to induction rule *}
331 note `A (Suc n) x` -- {* induction premise, stemming from fact a *}
332 show ?case sorry
333 qed
335 (2) This is how to perform induction over ``expressions of a certain
336 form'', using a locally defined inductive parameter n == "a x"
337 together with strengthening (the latter is usually required to get
338 sufficiently flexible induction hypotheses):
340 lemma
341 fixes a :: "'a => nat"
342 assumes a: "A (a x)"
343 shows "P (a x)"
344 using a
345 proof (induct n == "a x" arbitrary: x)
346 ...
348 See also HOL/Isar_examples/Puzzle.thy for an application of the this
349 particular technique.
351 (3) This is how to perform existential reasoning ('obtains' or
352 'obtain') by induction, while avoiding explicit object-logic
353 encodings:
355 lemma
356 fixes n :: nat
357 obtains x :: 'a where "P n x" and "Q n x"
358 proof (induct n arbitrary: thesis)
359 case 0
360 obtain x where "P 0 x" and "Q 0 x" sorry
361 then show thesis by (rule 0)
362 next
363 case (Suc n)
364 obtain x where "P n x" and "Q n x" by (rule Suc.hyps)
365 obtain x where "P (Suc n) x" and "Q (Suc n) x" sorry
366 then show thesis by (rule Suc.prems)
367 qed
369 Here the 'arbitrary: thesis' specification essentially modifies the
370 scope of the formal thesis parameter, in order to the get the whole
371 existence statement through the induction as expected.
373 * Provers/induct: mutual induction rules are now specified as a list
374 of rule sharing the same induction cases. HOL packages usually
375 provide foo_bar.inducts for mutually defined items foo and bar
376 (e.g. inductive sets or datatypes). INCOMPATIBILITY, users need to
377 specify mutual induction rules differently, i.e. like this:
379 (induct rule: foo_bar.inducts)
380 (induct set: foo bar)
381 (induct type: foo bar)
383 The ML function ProjectRule.projections turns old-style rules into the
384 new format.
386 * Provers/induct: improved handling of simultaneous goals. Instead of
387 introducing object-level conjunction, the statement is now split into
388 several conclusions, while the corresponding symbolic cases are
389 nested accordingly. INCOMPATIBILITY, proofs need to be structured
390 explicitly. For example:
392 lemma
393 fixes n :: nat
394 shows "P n" and "Q n"
395 proof (induct n)
396 case 0 case 1
397 show "P 0" sorry
398 next
399 case 0 case 2
400 show "Q 0" sorry
401 next
402 case (Suc n) case 1
403 note `P n` and `Q n`
404 show "P (Suc n)" sorry
405 next
406 case (Suc n) case 2
407 note `P n` and `Q n`
408 show "Q (Suc n)" sorry
409 qed
411 The split into subcases may be deferred as follows -- this is
412 particularly relevant for goal statements with local premises.
414 lemma
415 fixes n :: nat
416 shows "A n ==> P n" and "B n ==> Q n"
417 proof (induct n)
418 case 0
419 {
420 case 1
421 note `A 0`
422 show "P 0" sorry
423 next
424 case 2
425 note `B 0`
426 show "Q 0" sorry
427 }
428 next
429 case (Suc n)
430 note `A n ==> P n` and `B n ==> Q n`
431 {
432 case 1
433 note `A (Suc n)`
434 show "P (Suc n)" sorry
435 next
436 case 2
437 note `B (Suc n)`
438 show "Q (Suc n)" sorry
439 }
440 qed
442 If simultaneous goals are to be used with mutual rules, the statement
443 needs to be structured carefully as a two-level conjunction, using
444 lists of propositions separated by 'and':
446 lemma
447 shows "a : A ==> P1 a"
448 "a : A ==> P2 a"
449 and "b : B ==> Q1 b"
450 "b : B ==> Q2 b"
451 "b : B ==> Q3 b"
452 proof (induct set: A B)
454 * Provers/induct: support coinduction as well. See
455 src/HOL/Library/Coinductive_List.thy for various examples.
457 * Attribute "symmetric" produces result with standardized schematic
458 variables (index 0). Potential INCOMPATIBILITY.
460 * Simplifier: by default the simplifier trace only shows top level rewrites
461 now. That is, trace_simp_depth_limit is set to 1 by default. Thus there is
462 less danger of being flooded by the trace. The trace indicates where parts
463 have been suppressed.
465 * Provers/classical: removed obsolete classical version of elim_format
466 attribute; classical elim/dest rules are now treated uniformly when
467 manipulating the claset.
469 * Provers/classical: stricter checks to ensure that supplied intro,
470 dest and elim rules are well-formed; dest and elim rules must have at
471 least one premise.
473 * Provers/classical: attributes dest/elim/intro take an optional
474 weight argument for the rule (just as the Pure versions). Weights are
475 ignored by automated tools, but determine the search order of single
476 rule steps.
478 * Syntax: input syntax now supports dummy variable binding "%_. b",
479 where the body does not mention the bound variable. Note that dummy
480 patterns implicitly depend on their context of bounds, which makes
481 "{_. _}" match any set comprehension as expected. Potential
482 INCOMPATIBILITY -- parse translations need to cope with syntactic
483 constant "_idtdummy" in the binding position.
485 * Syntax: removed obsolete syntactic constant "_K" and its associated
486 parse translation. INCOMPATIBILITY -- use dummy abstraction instead,
487 for example "A -> B" => "Pi A (%_. B)".
489 * Pure: 'class_deps' command visualizes the subclass relation, using
490 the graph browser tool.
492 * Pure: 'print_theory' now suppresses entities with internal name
493 (trailing "_") by default; use '!' option for full details.
498 * New syntactic class "size"; overloaded constant "size" now
499 has type "'a::size ==> bool"
501 * Constants "Divides.op div", "Divides.op mod" and "Divides.op dvd" no named
502 "Divides.div", "Divides.mod" and "Divides.dvd"
503 INCOMPATIBILITY for ML code directly refering to constant names.
505 * Replaced "auto_term" by the conceptually simpler method "relation",
506 which just applies the instantiated termination rule with no further
507 simplifications.
509 Replace
510 termination by (auto_term "MYREL")
511 with
512 termination by (relation "MYREL") auto
514 * Automated termination proofs "by lexicographic_order" are now
515 included in the abbreviated function command "fun". No explicit
516 "termination" command is necessary anymore.
517 INCOMPATIBILITY: If a "fun"-definition cannot be proved terminating by
518 a lexicographic size order, then the command fails. Use the expanded
519 version "function" for these cases.
521 * New method "lexicographic_order" automatically synthesizes
522 termination relations as lexicographic combinations of size measures.
523 Usage for (function package) termination proofs:
525 termination
526 by lexicographic_order
528 * Records: generalised field-update to take a function on the field
529 rather than the new value: r(|A := x|) is translated to A_update (K x) r
530 The K-combinator that is internally used is called K_record.
531 INCOMPATIBILITY: Usage of the plain update functions has to be
532 adapted.
534 * axclass "semiring_0" now contains annihilation axioms
535 ("x * 0 = 0","0 * x = 0"), which are required for a semiring. Richer
536 structures do not inherit from semiring_0 anymore, because this property
537 is a theorem there, not an axiom.
538 INCOMPATIBILITY: In instances of semiring_0, there is more to prove, but
539 this is mostly trivial.
541 * axclass "recpower" was generalized to arbitrary monoids, not just
542 commutative semirings.
543 INCOMPATIBILITY: If you use recpower and need commutativity or a semiring
544 property, add the corresponding classes.
546 * Locale Lattic_Locales.partial_order changed (to achieve consistency with
547 axclass order):
548 - moved to Orderings.partial_order
549 - additional parameter ``less''
552 * Constant "List.list_all2" in List.thy now uses authentic syntax.
553 INCOMPATIBILITY: translations containing list_all2 may go wrong. On Isar
554 level, use abbreviations instead.
556 * Constant "List.op mem" in List.thy now has proper name: "List.memberl"
557 INCOMPATIBILITY: rarely occuring name references (e.g. ``List.op mem.simps'')
558 require renaming (e.g. ``List.memberl.simps'').
560 * Renamed constants in HOL.thy:
561 0 ~> HOL.zero
562 1 ~> HOL.one
563 INCOMPATIBILITY: ML code directly refering to constant names may need adaption
564 This in general only affects hand-written proof tactics, simprocs and so on.
566 * New theory Code_Generator providing class 'eq',
567 allowing for code generation with polymorphic equality.
569 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has been
570 abandoned in favour of plain 'int'. INCOMPATIBILITY -- Significant changes
571 for setting up numeral syntax for types:
573 - new constants Numeral.pred and Numeral.succ instead
574 of former Numeral.bin_pred and Numeral.bin_succ.
575 - Use integer operations instead of bin_add, bin_mult and so on.
576 - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
577 - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
579 See HOL/Integ/IntArith.thy for an example setup.
581 * New top level command 'normal_form' computes the normal form of a term
582 that may contain free variables. For example 'normal_form "rev[a,b,c]"'
583 prints '[b,c,a]'. This command is suitable for heavy-duty computations
584 because the functions are compiled to ML first.
585 INCOMPATIBILITY: new keywords 'normal_form' must quoted when used as
586 an identifier.
588 * Alternative iff syntax "A <-> B" for equality on bool (with priority
589 25 like -->); output depends on the "iff" print_mode, the default is
590 "A = B" (with priority 50).
592 * Renamed constants in HOL.thy and Orderings.thy:
593 op + ~> HOL.plus
594 op - ~> HOL.minus
595 uminus ~> HOL.uminus
596 op * ~> HOL.times
597 op < ~> Orderings.less
598 op <= ~> Orderings.less_eq
600 Adaptions may be required in the following cases:
602 a) User-defined constants using any of the names "plus", "minus", "times",
603 "less" or "less_eq". The standard syntax translations for "+", "-" and "*"
604 may go wrong.
605 INCOMPATIBILITY: use more specific names.
607 b) Variables named "plus", "minus", "times", "less", "less_eq"
608 INCOMPATIBILITY: use more specific names.
610 c) Permutative equations (e.g. "a + b = b + a")
611 Since the change of names also changes the order of terms, permutative
612 rewrite rules may get applied in a different order. Experience shows that
613 this is rarely the case (only two adaptions in the whole Isabelle
614 distribution).
615 INCOMPATIBILITY: rewrite proofs
617 d) ML code directly refering to constant names
618 This in general only affects hand-written proof tactics, simprocs and so on.
619 INCOMPATIBILITY: grep your sourcecode and replace names.
621 * Relations less (<) and less_eq (<=) are also available on type bool.
622 Modified syntax to disallow nesting without explicit parentheses,
623 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".
625 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
627 * Relation composition operator "op O" now has precedence 75 and binds
628 stronger than union and intersection. INCOMPATIBILITY.
630 * The old set interval syntax "{m..n(}" (and relatives) has been removed.
631 Use "{m..<n}" (and relatives) instead.
633 * In the context of the assumption "~(s = t)" the Simplifier rewrites
634 "t = s" to False (by simproc "neq_simproc"). For backward
635 compatibility this can be disabled by ML "reset use_neq_simproc".
637 * "m dvd n" where m and n are numbers is evaluated to True/False by simp.
639 * Theorem Cons_eq_map_conv no longer has attribute `simp'.
641 * Theorem setsum_mult renamed to setsum_right_distrib.
643 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
644 'rule' method.
646 * Tactics 'sat' and 'satx' reimplemented, several improvements: goals
647 no longer need to be stated as "<prems> ==> False", equivalences (i.e.
648 "=" on type bool) are handled, variable names of the form "lit_<n>"
649 are no longer reserved, significant speedup.
651 * Tactics 'sat' and 'satx' can now replay MiniSat proof traces. zChaff is
652 still supported as well.
654 * inductive and datatype: provide projections of mutual rules, bundled
655 as foo_bar.inducts;
657 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to Library.
659 * Library: moved theory Accessible_Part to main HOL.
661 * Library: added theory Coinductive_List of potentially infinite lists
662 as greatest fixed-point.
664 * Library: added theory AssocList which implements (finite) maps as
665 association lists.
667 * New proof method "evaluation" for efficiently solving a goal (i.e. a
668 boolean expression) by compiling it to ML. The goal is "proved" (via
669 the oracle "Evaluation") if it evaluates to True.
671 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
672 also when invoked by the simplifier. This results in the simplifier
673 being more powerful on arithmetic goals. INCOMPATIBILITY. Set
674 fast_arith_split_limit to 0 to obtain the old behavior.
676 * Support for hex (0x20) and binary (0b1001) numerals.
678 * New method: reify eqs (t), where eqs are equations for an
679 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
680 parameter, computes a term s::'b and a list xs::'a list and proves the
681 theorem I xs s = t. This is also known as reification or quoting. The
682 resulting theorem is applied to the subgoal to substitute t with I xs
683 s. If t is omitted, the subgoal itself is reified.
685 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
686 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
687 where f is supposed to be a computable function (in the sense of code
688 generattion). The method uses reify to compute s and xs as above then
689 applies corr_thm and uses normalization by evaluation to "prove" f s =
690 r and finally gets the theorem t = r, which is again applied to the
691 subgoal. An Example is available in HOL/ex/ReflectionEx.thy.
693 * Reflection: Automatic refification now handels binding, an example
694 is available in HOL/ex/ReflectionEx.thy
697 *** HOL-Algebra ***
699 * Formalisation of ideals and the quotient construction over rings.
701 * Order and lattice theory no longer based on records.
704 * Method algebra is now set up via an attribute. For examples see
705 CRing.thy. INCOMPATIBILITY: the method is now weaker on combinations
706 of algebraic structures.
708 * Renamed `CRing.thy' to `Ring.thy'. INCOMPATIBILITY.
711 *** HOL-Complex ***
713 * Theory Real: new method ferrack implements quantifier elimination
714 for linear arithmetic over the reals. The quantifier elimination
715 feature is used only for decision, for compatibility with arith. This
716 means a goal is either solved or left unchanged, no simplification.
721 * Pure/table:
723 Function `...tab.foldl` removed.
724 INCOMPATIBILITY: use `...tabfold` instead
726 * Pure/library:
728 `gen_rem(s)` abandoned in favour of `remove` / `subtract`.
730 rewrite "gen_rem eq (xs, x)" to "remove (eq o swap) x xs"
731 rewrite "gen_rems eq (xs, ys)" to "subtract (eq o swap) ys xs"
732 drop "swap" if "eq" is symmetric.
734 * Pure/library:
736 infixes `ins` `ins_string` `ins_int` have been abandoned in favour of `insert`.
737 INCOMPATIBILITY: rewrite "x ins(_...) xs" to "insert (op =) x xs"
739 * Pure/General/susp.ML:
741 New module for delayed evaluations.
743 * Pure/library:
745 Semantically identical functions "equal_list" and "eq_list" have been
746 unified to "eq_list".
748 * Pure/library:
750 val burrow: ('a list -> 'b list) -> 'a list list -> 'b list list
751 val fold_burrow: ('a list -> 'c -> 'b list * 'd) -> 'a list list -> 'c -> 'b list list * 'd
753 The semantics of "burrow" is: "take a function with *simulatanously*
754 transforms a list of value, and apply it *simulatanously* to a list of
755 list of values of the appropriate type". Confer this with "map" which
756 would *not* apply its argument function simulatanously but in
757 sequence. "fold_burrow" has an additional context.
759 Both actually avoid the usage of "unflat" since they hide away
760 "unflat" from the user.
762 * Pure/library: functions map2 and fold2 with curried syntax for
763 simultanous mapping and folding:
765 val map2: ('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list
766 val fold2: ('a -> 'b -> 'c -> 'c) -> 'a list -> 'b list -> 'c -> 'c
768 * Pure/library: indexed lists - some functions in the Isabelle library
769 treating lists over 'a as finite mappings from [0...n] to 'a have been
770 given more convenient names and signatures reminiscent of similar
771 functions for alists, tables, etc:
773 val nth: 'a list -> int -> 'a
774 val nth_map: int -> ('a -> 'a) -> 'a list -> 'a list
775 val fold_index: (int * 'a -> 'b -> 'b) -> 'a list -> 'b -> 'b
777 Note that fold_index starts counting at index 0, not 1 like foldln
778 used to.
780 * Pure/library: general ``divide_and_conquer'' combinator on lists.
782 * Pure/General/name_mangler.ML provides a functor for generic name
783 mangling (bijective mapping from expression values to strings).
785 * Pure/General/rat.ML implements rational numbers.
787 * Pure/General/table.ML: the join operations now works via exceptions
788 DUP/SAME instead of type option. This is simpler in simple cases, and
789 admits slightly more efficient complex applications.
791 * Pure: datatype Context.generic joins theory/Proof.context and
792 provides some facilities for code that works in either kind of
793 context, notably GenericDataFun for uniform theory and proof data.
795 * Pure: 'advanced' translation functions (parse_translation etc.) now
796 use Context.generic instead of just theory.
798 * Pure: simplified internal attribute type, which is now always
799 Context.generic * thm -> Context.generic * thm. Global (theory)
800 vs. local (Proof.context) attributes have been discontinued, while
801 minimizing code duplication. Thm.rule_attribute and
802 Thm.declaration_attribute build canonical attributes; see also
803 structure Context for further operations on Context.generic, notably
804 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
805 declarations and definitions.
807 * Pure/kernel: consts certification ignores sort constraints given in
808 signature declarations. (This information is not relevant to the
809 logic, but only for type inference.) IMPORTANT INTERNAL CHANGE.
811 * Pure: axiomatic type classes are now purely definitional, with
812 explicit proofs of class axioms and super class relations performed
813 internally. See Pure/axclass.ML for the main internal interfaces --
814 notably AxClass.define_class supercedes AxClass.add_axclass, and
815 AxClass.axiomatize_class/classrel/arity supercede
816 Sign.add_classes/classrel/arities.
818 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
819 global/local versions on theory vs. Proof.context have been
820 discontinued; Attrib.syntax and Method.syntax have been adapted
821 accordingly. INCOMPATIBILITY, need to adapt parser expressions for
822 attributes, methods, etc.
824 * Pure: several functions of signature "... -> theory -> theory * ..."
825 have been reoriented to "... -> theory -> ... * theory" in order to
826 allow natural usage in combination with the ||>, ||>>, |-> and
827 fold_map combinators.
829 * Pure: official theorem names (closed derivations) and additional
830 comments (tags) are now strictly separate. Name hints -- which are
831 maintained as tags -- may be attached any time without affecting the
832 derivation.
834 * Pure: primitive rule lift_rule now takes goal cterm instead of an
835 actual goal state (thm). Use Thm.lift_rule (Thm.cprem_of st i) to
836 achieve the old behaviour.
838 * Pure: the "Goal" constant is now called "prop", supporting a
839 slightly more general idea of ``protecting'' meta-level rule
840 statements.
842 * Pure: Logic.(un)varify only works in a global context, which is now
843 enforced instead of silently assumed. INCOMPATIBILITY, may use
844 Logic.legacy_(un)varify as temporary workaround.
846 * Pure: structure Name provides scalable operations for generating
847 internal variable names, notably Name.variants etc. This replaces
848 some popular functions from term.ML:
850 Term.variant -> Name.variant
851 Term.variantlist -> Name.variant_list (*canonical argument order*)
852 Term.invent_names -> Name.invent_list
854 Note that low-level renaming rarely occurs in new code -- operations
855 from structure Variable are used instead (see below).
857 * Pure: structure Variable provides fundamental operations for proper
858 treatment of fixed/schematic variables in a context. For example,
859 Variable.import introduces fixes for schematics of given facts and
860 Variable.export reverses the effect (up to renaming) -- this replaces
861 various freeze_thaw operations.
863 * Pure: structure Goal provides simple interfaces for
864 init/conclude/finish and tactical prove operations (replacing former
865 Tactic.prove). Goal.prove is the canonical way to prove results
866 within a given context; Goal.prove_global is a degraded version for
867 theory level goals, including a global Drule.standard. Note that
868 OldGoals.prove_goalw_cterm has long been obsolete, since it is
869 ill-behaved in a local proof context (e.g. with local fixes/assumes or
870 in a locale context).
872 * Isar: simplified treatment of user-level errors, using exception
873 ERROR of string uniformly. Function error now merely raises ERROR,
874 without any side effect on output channels. The Isar toplevel takes
875 care of proper display of ERROR exceptions. ML code may use plain
876 handle/can/try; cat_error may be used to concatenate errors like this:
878 ... handle ERROR msg => cat_error msg "..."
880 Toplevel ML code (run directly or through the Isar toplevel) may be
881 embedded into the Isar toplevel with exception display/debug like
882 this:
884 Isar.toplevel (fn () => ...)
886 INCOMPATIBILITY, removed special transform_error facilities, removed
887 obsolete variants of user-level exceptions (ERROR_MESSAGE,
888 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
889 -- use plain ERROR instead.
891 * Isar: theory setup now has type (theory -> theory), instead of a
892 list. INCOMPATIBILITY, may use #> to compose setup functions.
894 * Isar: installed ML toplevel pretty printer for type Proof.context,
895 subject to ProofContext.debug/verbose flags.
897 * Isar: Toplevel.theory_to_proof admits transactions that modify the
898 theory before entering a proof state. Transactions now always see a
899 quasi-functional intermediate checkpoint, both in interactive and
900 batch mode.
902 * Simplifier: the simpset of a running simplification process now
903 contains a proof context (cf. Simplifier.the_context), which is the
904 very context that the initial simpset has been retrieved from (by
905 simpset_of/local_simpset_of). Consequently, all plug-in components
906 (solver, looper etc.) may depend on arbitrary proof data.
908 * Simplifier.inherit_context inherits the proof context (plus the
909 local bounds) of the current simplification process; any simproc
910 etc. that calls the Simplifier recursively should do this! Removed
911 former Simplifier.inherit_bounds, which is already included here --
912 INCOMPATIBILITY. Tools based on low-level rewriting may even have to
913 specify an explicit context using Simplifier.context/theory_context.
915 * Simplifier/Classical Reasoner: more abstract interfaces
916 change_simpset/claset for modifying the simpset/claset reference of a
917 theory; raw versions simpset/claset_ref etc. have been discontinued --
920 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
921 "Trueprop" etc.
924 *** System ***
926 * settings: ML_IDENTIFIER -- which is appended to user specific heap
927 locations -- now includes the Isabelle version identifier as well.
928 This simplifies use of multiple Isabelle installations.
930 * isabelle-process: option -S (secure mode) disables some critical
931 operations, notably runtime compilation and evaluation of ML source
932 code.
935 New in Isabelle2005 (October 2005)
936 ----------------------------------
938 *** General ***
940 * Theory headers: the new header syntax for Isar theories is
942 theory <name>
943 imports <theory1> ... <theoryN>
944 uses <file1> ... <fileM>
945 begin
947 where the 'uses' part is optional. The previous syntax
949 theory <name> = <theory1> + ... + <theoryN>:
951 will disappear in the next release. Use isatool fixheaders to convert
952 existing theory files. Note that there is no change in ancient
953 non-Isar theories now, but these will disappear soon.
955 * Theory loader: parent theories can now also be referred to via
956 relative and absolute paths.
958 * Command 'find_theorems' searches for a list of criteria instead of a
959 list of constants. Known criteria are: intro, elim, dest, name:string,
960 simp:term, and any term. Criteria can be preceded by '-' to select
961 theorems that do not match. Intro, elim, dest select theorems that
962 match the current goal, name:s selects theorems whose fully qualified
963 name contain s, and simp:term selects all simplification rules whose
964 lhs match term. Any other term is interpreted as pattern and selects
965 all theorems matching the pattern. Available in ProofGeneral under
966 'ProofGeneral -> Find Theorems' or C-c C-f. Example:
968 C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
970 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
971 matching the current goal as introduction rule and not having "HOL."
972 in their name (i.e. not being defined in theory HOL).
974 * Command 'thms_containing' has been discontinued in favour of
975 'find_theorems'; INCOMPATIBILITY.
977 * Communication with Proof General is now 8bit clean, which means that
978 Unicode text in UTF-8 encoding may be used within theory texts (both
979 formal and informal parts). Cf. option -U of the Isabelle Proof
980 General interface. Here are some simple examples (cf. src/HOL/ex):
982 http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
983 http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
985 * Improved efficiency of the Simplifier and, to a lesser degree, the
986 Classical Reasoner. Typical big applications run around 2 times
987 faster.
990 *** Document preparation ***
992 * Commands 'display_drafts' and 'print_drafts' perform simple output
993 of raw sources. Only those symbols that do not require additional
994 LaTeX packages (depending on comments in isabellesym.sty) are
995 displayed properly, everything else is left verbatim. isatool display
996 and isatool print are used as front ends (these are subject to the
997 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
999 * Command tags control specific markup of certain regions of text,
1000 notably folding and hiding. Predefined tags include "theory" (for
1001 theory begin and end), "proof" for proof commands, and "ML" for
1002 commands involving ML code; the additional tags "visible" and
1003 "invisible" are unused by default. Users may give explicit tag
1004 specifications in the text, e.g. ''by %invisible (auto)''. The
1005 interpretation of tags is determined by the LaTeX job during document
1006 preparation: see option -V of isatool usedir, or options -n and -t of
1007 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
1008 \isadroptag.
1010 Several document versions may be produced at the same time via isatool
1011 usedir (the generated index.html will link all of them). Typical
1012 specifications include ''-V document=theory,proof,ML'' to present
1013 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
1014 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
1015 these parts without any formal replacement text. The Isabelle site
1016 default settings produce ''document'' and ''outline'' versions as
1017 specified above.
1019 * Several new antiquotations:
1021 @{term_type term} prints a term with its type annotated;
1023 @{typeof term} prints the type of a term;
1025 @{const const} is the same as @{term const}, but checks that the
1026 argument is a known logical constant;
1028 @{term_style style term} and @{thm_style style thm} print a term or
1029 theorem applying a "style" to it
1031 @{ML text}
1033 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
1034 definitions, equations, inequations etc., 'concl' printing only the
1035 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
1036 to print the specified premise. TermStyle.add_style provides an ML
1037 interface for introducing further styles. See also the "LaTeX Sugar"
1038 document practical applications. The ML antiquotation prints
1039 type-checked ML expressions verbatim.
1041 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
1042 and 'text' support optional locale specification '(in loc)', which
1043 specifies the default context for interpreting antiquotations. For
1044 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
1046 * Option 'locale=NAME' of antiquotations specifies an alternative
1047 context interpreting the subsequent argument. For example: @{thm
1048 [locale=lattice] inf_assoc}.
1050 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
1051 a proof context.
1053 * Proper output of antiquotations for theory commands involving a
1054 proof context (such as 'locale' or 'theorem (in loc) ...').
1056 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
1057 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
1059 * isatool usedir: new option -C (default true) controls whether option
1060 -D should include a copy of the original document directory; -C false
1061 prevents unwanted effects such as copying of administrative CVS data.
1064 *** Pure ***
1066 * Considerably improved version of 'constdefs' command. Now performs
1067 automatic type-inference of declared constants; additional support for
1068 local structure declarations (cf. locales and HOL records), see also
1069 isar-ref manual. Potential INCOMPATIBILITY: need to observe strictly
1070 sequential dependencies of definitions within a single 'constdefs'
1071 section; moreover, the declared name needs to be an identifier. If
1072 all fails, consider to fall back on 'consts' and 'defs' separately.
1074 * Improved indexed syntax and implicit structures. First of all,
1075 indexed syntax provides a notational device for subscripted
1076 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
1077 expressions. Secondly, in a local context with structure
1078 declarations, number indexes \<^sub>n or the empty index (default
1079 number 1) refer to a certain fixed variable implicitly; option
1080 show_structs controls printing of implicit structures. Typical
1081 applications of these concepts involve record types and locales.
1083 * New command 'no_syntax' removes grammar declarations (and
1084 translations) resulting from the given syntax specification, which is
1085 interpreted in the same manner as for the 'syntax' command.
1087 * 'Advanced' translation functions (parse_translation etc.) may depend
1088 on the signature of the theory context being presently used for
1089 parsing/printing, see also isar-ref manual.
1091 * Improved 'oracle' command provides a type-safe interface to turn an
1092 ML expression of type theory -> T -> term into a primitive rule of
1093 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
1094 is already included here); see also FOL/ex/IffExample.thy;
1097 * axclass: name space prefix for class "c" is now "c_class" (was "c"
1098 before); "cI" is no longer bound, use "c.intro" instead.
1099 INCOMPATIBILITY. This change avoids clashes of fact bindings for
1100 axclasses vs. locales.
1102 * Improved internal renaming of symbolic identifiers -- attach primes
1103 instead of base 26 numbers.
1105 * New flag show_question_marks controls printing of leading question
1106 marks in schematic variable names.
1108 * In schematic variable names, *any* symbol following \<^isub> or
1109 \<^isup> is now treated as part of the base name. For example, the
1110 following works without printing of awkward ".0" indexes:
1112 lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
1113 by simp
1115 * Inner syntax includes (*(*nested*) comments*).
1117 * Pretty printer now supports unbreakable blocks, specified in mixfix
1118 annotations as "(00...)".
1120 * Clear separation of logical types and nonterminals, where the latter
1121 may only occur in 'syntax' specifications or type abbreviations.
1122 Before that distinction was only partially implemented via type class
1123 "logic" vs. "{}". Potential INCOMPATIBILITY in rare cases of improper
1124 use of 'types'/'consts' instead of 'nonterminals'/'syntax'. Some very
1125 exotic syntax specifications may require further adaption
1126 (e.g. Cube/Cube.thy).
1128 * Removed obsolete type class "logic", use the top sort {} instead.
1129 Note that non-logical types should be declared as 'nonterminals'
1130 rather than 'types'. INCOMPATIBILITY for new object-logic
1131 specifications.
1133 * Attributes 'induct' and 'cases': type or set names may now be
1134 locally fixed variables as well.
1136 * Simplifier: can now control the depth to which conditional rewriting
1137 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
1138 Limit.
1140 * Simplifier: simplification procedures may now take the current
1141 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
1142 interface), which is very useful for calling the Simplifier
1143 recursively. Minor INCOMPATIBILITY: the 'prems' argument of simprocs
1144 is gone -- use prems_of_ss on the simpset instead. Moreover, the
1145 low-level mk_simproc no longer applies Logic.varify internally, to
1146 allow for use in a context of fixed variables.
1148 * thin_tac now works even if the assumption being deleted contains !!
1149 or ==>. More generally, erule now works even if the major premise of
1150 the elimination rule contains !! or ==>.
1152 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
1154 * Reorganized bootstrapping of the Pure theories; CPure is now derived
1155 from Pure, which contains all common declarations already. Both
1156 theories are defined via plain Isabelle/Isar .thy files.
1157 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
1158 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
1159 use isatool fixcpure to adapt your theory and ML sources.
1161 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
1162 selections of theorems in named facts via index ranges.
1164 * 'print_theorems': in theory mode, really print the difference
1165 wrt. the last state (works for interactive theory development only),
1166 in proof mode print all local facts (cf. 'print_facts');
1168 * 'hide': option '(open)' hides only base names.
1170 * More efficient treatment of intermediate checkpoints in interactive
1171 theory development.
1173 * Code generator is now invoked via code_module (incremental code
1174 generation) and code_library (modular code generation, ML structures
1175 for each theory). INCOMPATIBILITY: new keywords 'file' and 'contains'
1176 must be quoted when used as identifiers.
1178 * New 'value' command for reading, evaluating and printing terms using
1179 the code generator. INCOMPATIBILITY: command keyword 'value' must be
1180 quoted when used as identifier.
1183 *** Locales ***
1185 * New commands for the interpretation of locale expressions in
1186 theories (1), locales (2) and proof contexts (3). These generate
1187 proof obligations from the expression specification. After the
1188 obligations have been discharged, theorems of the expression are added
1189 to the theory, target locale or proof context. The synopsis of the
1190 commands is a follows:
1192 (1) interpretation expr inst
1193 (2) interpretation target < expr
1194 (3) interpret expr inst
1196 Interpretation in theories and proof contexts require a parameter
1197 instantiation of terms from the current context. This is applied to
1198 specifications and theorems of the interpreted expression.
1199 Interpretation in locales only permits parameter renaming through the
1200 locale expression. Interpretation is smart in that interpretations
1201 that are active already do not occur in proof obligations, neither are
1202 instantiated theorems stored in duplicate. Use 'print_interps' to
1203 inspect active interpretations of a particular locale. For details,
1204 see the Isar Reference manual. Examples can be found in
1205 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
1207 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
1208 'interpret' instead.
1210 * New context element 'constrains' for adding type constraints to
1211 parameters.
1213 * Context expressions: renaming of parameters with syntax
1214 redeclaration.
1216 * Locale declaration: 'includes' disallowed.
1218 * Proper static binding of attribute syntax -- i.e. types / terms /
1219 facts mentioned as arguments are always those of the locale definition
1220 context, independently of the context of later invocations. Moreover,
1221 locale operations (renaming and type / term instantiation) are applied
1222 to attribute arguments as expected.
1224 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
1225 actual attributes; rare situations may require Attrib.attribute to
1226 embed those attributes into Attrib.src that lack concrete syntax.
1227 Attribute implementations need to cooperate properly with the static
1228 binding mechanism. Basic parsers Args.XXX_typ/term/prop and
1229 Attrib.XXX_thm etc. already do the right thing without further
1230 intervention. Only unusual applications -- such as "where" or "of"
1231 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
1232 on the context and the facts involved -- may have to assign parsed
1233 values to argument tokens explicitly.
1235 * Changed parameter management in theorem generation for long goal
1236 statements with 'includes'. INCOMPATIBILITY: produces a different
1237 theorem statement in rare situations.
1239 * Locale inspection command 'print_locale' omits notes elements. Use
1240 'print_locale!' to have them included in the output.
1243 *** Provers ***
1245 * Provers/hypsubst.ML: improved version of the subst method, for
1246 single-step rewriting: it now works in bound variable contexts. New is
1247 'subst (asm)', for rewriting an assumption. INCOMPATIBILITY: may
1248 rewrite a different subterm than the original subst method, which is
1249 still available as 'simplesubst'.
1251 * Provers/quasi.ML: new transitivity reasoners for transitivity only
1252 and quasi orders.
1254 * Provers/trancl.ML: new transitivity reasoner for transitive and
1255 reflexive-transitive closure of relations.
1257 * Provers/blast.ML: new reference depth_limit to make blast's depth
1258 limit (previously hard-coded with a value of 20) user-definable.
1260 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
1261 is peformed already. Object-logics merely need to finish their
1262 initial simpset configuration as before. INCOMPATIBILITY.
1267 * Symbolic syntax of Hilbert Choice Operator is now as follows:
1269 syntax (epsilon)
1270 "_Eps" :: "[pttrn, bool] => 'a" ("(3\<some>_./ _)" [0, 10] 10)
1272 The symbol \<some> is displayed as the alternative epsilon of LaTeX
1273 and x-symbol; use option '-m epsilon' to get it actually printed.
1274 Moreover, the mathematically important symbolic identifier \<epsilon>
1275 becomes available as variable, constant etc. INCOMPATIBILITY,
1277 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
1278 Similarly for all quantifiers: "ALL x > y" etc. The x-symbol for >=
1279 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
1280 support corresponding Isar calculations.
1282 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
1283 instead of ":".
1285 * theory SetInterval: changed the syntax for open intervals:
1287 Old New
1288 {..n(} {..<n}
1289 {)n..} {n<..}
1290 {m..n(} {m..<n}
1291 {)m..n} {m<..n}
1292 {)m..n(} {m<..<n}
1294 The old syntax is still supported but will disappear in the next
1295 release. For conversion use the following Emacs search and replace
1296 patterns (these are not perfect but work quite well):
1298 {)\([^\.]*\)\.\. -> {\1<\.\.}
1299 \.\.\([^(}]*\)(} -> \.\.<\1}
1301 * Theory Commutative_Ring (in Library): method comm_ring for proving
1302 equalities in commutative rings; method 'algebra' provides a generic
1303 interface.
1305 * Theory Finite_Set: changed the syntax for 'setsum', summation over
1306 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
1307 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
1308 be a tuple pattern.
1310 Some new syntax forms are available:
1312 "\<Sum>x | P. e" for "setsum (%x. e) {x. P}"
1313 "\<Sum>x = a..b. e" for "setsum (%x. e) {a..b}"
1314 "\<Sum>x = a..<b. e" for "setsum (%x. e) {a..<b}"
1315 "\<Sum>x < k. e" for "setsum (%x. e) {..<k}"
1317 The latter form "\<Sum>x < k. e" used to be based on a separate
1318 function "Summation", which has been discontinued.
1320 * theory Finite_Set: in structured induction proofs, the insert case
1321 is now 'case (insert x F)' instead of the old counterintuitive 'case
1322 (insert F x)'.
1324 * The 'refute' command has been extended to support a much larger
1325 fragment of HOL, including axiomatic type classes, constdefs and
1326 typedefs, inductive datatypes and recursion.
1328 * New tactics 'sat' and 'satx' to prove propositional tautologies.
1329 Requires zChaff with proof generation to be installed. See
1330 HOL/ex/SAT_Examples.thy for examples.
1332 * Datatype induction via method 'induct' now preserves the name of the
1333 induction variable. For example, when proving P(xs::'a list) by
1334 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
1335 than P(list) ==> P(a#list) as previously. Potential INCOMPATIBILITY
1336 in unstructured proof scripts.
1338 * Reworked implementation of records. Improved scalability for
1339 records with many fields, avoiding performance problems for type
1340 inference. Records are no longer composed of nested field types, but
1341 of nested extension types. Therefore the record type only grows linear
1342 in the number of extensions and not in the number of fields. The
1343 top-level (users) view on records is preserved. Potential
1344 INCOMPATIBILITY only in strange cases, where the theory depends on the
1345 old record representation. The type generated for a record is called
1346 <record_name>_ext_type.
1348 Flag record_quick_and_dirty_sensitive can be enabled to skip the
1349 proofs triggered by a record definition or a simproc (if
1350 quick_and_dirty is enabled). Definitions of large records can take
1351 quite long.
1353 New simproc record_upd_simproc for simplification of multiple record
1354 updates enabled by default. Moreover, trivial updates are also
1355 removed: r(|x := x r|) = r. INCOMPATIBILITY: old proofs break
1356 occasionally, since simplification is more powerful by default.
1358 * typedef: proper support for polymorphic sets, which contain extra
1359 type-variables in the term.
1361 * Simplifier: automatically reasons about transitivity chains
1362 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
1363 provided by Provers/trancl.ML as additional solvers. INCOMPATIBILITY:
1364 old proofs break occasionally as simplification may now solve more
1365 goals than previously.
1367 * Simplifier: converts x <= y into x = y if assumption y <= x is
1368 present. Works for all partial orders (class "order"), in particular
1369 numbers and sets. For linear orders (e.g. numbers) it treats ~ x < y
1370 just like y <= x.
1372 * Simplifier: new simproc for "let x = a in f x". If a is a free or
1373 bound variable or a constant then the let is unfolded. Otherwise
1374 first a is simplified to b, and then f b is simplified to g. If
1375 possible we abstract b from g arriving at "let x = b in h x",
1376 otherwise we unfold the let and arrive at g. The simproc can be
1377 enabled/disabled by the reference use_let_simproc. Potential
1378 INCOMPATIBILITY since simplification is more powerful by default.
1380 * Classical reasoning: the meson method now accepts theorems as arguments.
1382 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
1383 jobs to provide advice on the provability of subgoals.
1385 * Theory OrderedGroup and Ring_and_Field: various additions and
1386 improvements to faciliate calculations involving equalities and
1387 inequalities.
1389 The following theorems have been eliminated or modified
1392 abs_eq now named abs_of_nonneg
1393 abs_of_ge_0 now named abs_of_nonneg
1394 abs_minus_eq now named abs_of_nonpos
1395 imp_abs_id now named abs_of_nonneg
1396 imp_abs_neg_id now named abs_of_nonpos
1397 mult_pos now named mult_pos_pos
1398 mult_pos_le now named mult_nonneg_nonneg
1399 mult_pos_neg_le now named mult_nonneg_nonpos
1400 mult_pos_neg2_le now named mult_nonneg_nonpos2
1401 mult_neg now named mult_neg_neg
1402 mult_neg_le now named mult_nonpos_nonpos
1404 * Theory Parity: added rules for simplifying exponents.
1406 * Theory List:
1408 The following theorems have been eliminated or modified
1411 list_all_Nil now named list_all.simps(1)
1412 list_all_Cons now named list_all.simps(2)
1413 list_all_conv now named list_all_iff
1414 set_mem_eq now named mem_iff
1416 * Theories SetsAndFunctions and BigO (see HOL/Library) support
1417 asymptotic "big O" calculations. See the notes in BigO.thy.
1420 *** HOL-Complex ***
1422 * Theory RealDef: better support for embedding natural numbers and
1423 integers in the reals.
1425 The following theorems have been eliminated or modified
1428 exp_ge_add_one_self now requires no hypotheses
1429 real_of_int_add reversed direction of equality (use [symmetric])
1430 real_of_int_minus reversed direction of equality (use [symmetric])
1431 real_of_int_diff reversed direction of equality (use [symmetric])
1432 real_of_int_mult reversed direction of equality (use [symmetric])
1434 * Theory RComplete: expanded support for floor and ceiling functions.
1436 * Theory Ln is new, with properties of the natural logarithm
1438 * Hyperreal: There is a new type constructor "star" for making
1439 nonstandard types. The old type names are now type synonyms:
1441 hypreal = real star
1442 hypnat = nat star
1443 hcomplex = complex star
1445 * Hyperreal: Many groups of similarly-defined constants have been
1446 replaced by polymorphic versions (INCOMPATIBILITY):
1448 star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
1450 starset <-- starsetNat, starsetC
1451 *s* <-- *sNat*, *sc*
1452 starset_n <-- starsetNat_n, starsetC_n
1453 *sn* <-- *sNatn*, *scn*
1454 InternalSets <-- InternalNatSets, InternalCSets
1456 starfun <-- starfun{Nat,Nat2,C,RC,CR}
1457 *f* <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
1458 starfun_n <-- starfun{Nat,Nat2,C,RC,CR}_n
1459 *fn* <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
1460 InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
1462 * Hyperreal: Many type-specific theorems have been removed in favor of
1463 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
1465 add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
1466 add_assoc <-- {hypreal,hypnat,hcomplex}_add_assocs
1467 OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
1468 OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
1469 right_minus <-- hypreal_add_minus
1470 left_minus <-- {hypreal,hcomplex}_add_minus_left
1471 mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
1472 mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
1473 mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
1474 mult_1_right <-- hcomplex_mult_one_right
1475 mult_zero_left <-- hcomplex_mult_zero_left
1476 left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
1477 right_distrib <-- hypnat_add_mult_distrib2
1478 zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
1479 right_inverse <-- hypreal_mult_inverse
1480 left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
1481 order_refl <-- {hypreal,hypnat}_le_refl
1482 order_trans <-- {hypreal,hypnat}_le_trans
1483 order_antisym <-- {hypreal,hypnat}_le_anti_sym
1484 order_less_le <-- {hypreal,hypnat}_less_le
1485 linorder_linear <-- {hypreal,hypnat}_le_linear
1486 add_left_mono <-- {hypreal,hypnat}_add_left_mono
1487 mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
1488 add_nonneg_nonneg <-- hypreal_le_add_order
1490 * Hyperreal: Separate theorems having to do with type-specific
1491 versions of constants have been merged into theorems that apply to the
1492 new polymorphic constants (INCOMPATIBILITY):
1494 STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
1495 STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
1496 STAR_Un <-- {STAR,NatStar,STARC}_Un
1497 STAR_Int <-- {STAR,NatStar,STARC}_Int
1498 STAR_Compl <-- {STAR,NatStar,STARC}_Compl
1499 STAR_subset <-- {STAR,NatStar,STARC}_subset
1500 STAR_mem <-- {STAR,NatStar,STARC}_mem
1501 STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
1502 STAR_diff <-- {STAR,STARC}_diff
1503 STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
1504 STARC_hcomplex_of_complex}_image_subset
1505 starset_n_Un <-- starset{Nat,C}_n_Un
1506 starset_n_Int <-- starset{Nat,C}_n_Int
1507 starset_n_Compl <-- starset{Nat,C}_n_Compl
1508 starset_n_diff <-- starset{Nat,C}_n_diff
1509 InternalSets_Un <-- Internal{Nat,C}Sets_Un
1510 InternalSets_Int <-- Internal{Nat,C}Sets_Int
1511 InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
1512 InternalSets_diff <-- Internal{Nat,C}Sets_diff
1513 InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
1514 InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
1515 starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
1516 starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
1517 starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
1518 starfun <-- starfun{Nat,Nat2,C,RC,CR}
1519 starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
1520 starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
1521 starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
1522 starfun_diff <-- starfun{C,RC,CR}_diff
1523 starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
1524 starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
1525 starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
1526 starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
1527 starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
1528 starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
1529 starfun_Id <-- starfunC_Id
1530 starfun_approx <-- starfun{Nat,CR}_approx
1531 starfun_capprox <-- starfun{C,RC}_capprox
1532 starfun_abs <-- starfunNat_rabs
1533 starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
1534 starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
1535 starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
1536 starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
1537 starfun_add_capprox <-- starfun{C,RC}_add_capprox
1538 starfun_add_approx <-- starfunCR_add_approx
1539 starfun_inverse_inverse <-- starfunC_inverse_inverse
1540 starfun_divide <-- starfun{C,CR,RC}_divide
1541 starfun_n <-- starfun{Nat,C}_n
1542 starfun_n_mult <-- starfun{Nat,C}_n_mult
1543 starfun_n_add <-- starfun{Nat,C}_n_add
1544 starfun_n_add_minus <-- starfunNat_n_add_minus
1545 starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
1546 starfun_n_minus <-- starfun{Nat,C}_n_minus
1547 starfun_n_eq <-- starfun{Nat,C}_n_eq
1549 star_n_add <-- {hypreal,hypnat,hcomplex}_add
1550 star_n_minus <-- {hypreal,hcomplex}_minus
1551 star_n_diff <-- {hypreal,hcomplex}_diff
1552 star_n_mult <-- {hypreal,hcomplex}_mult
1553 star_n_inverse <-- {hypreal,hcomplex}_inverse
1554 star_n_le <-- {hypreal,hypnat}_le
1555 star_n_less <-- {hypreal,hypnat}_less
1556 star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
1557 star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
1558 star_n_abs <-- hypreal_hrabs
1559 star_n_divide <-- hcomplex_divide
1561 star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
1562 star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
1563 star_of_diff <-- hypreal_of_real_diff
1564 star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
1565 star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
1566 star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
1567 star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
1568 star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
1569 star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
1570 star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
1571 star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
1572 star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
1573 star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
1574 star_of_number_of <-- {hypreal,hcomplex}_number_of
1575 star_of_number_less <-- number_of_less_hypreal_of_real_iff
1576 star_of_number_le <-- number_of_le_hypreal_of_real_iff
1577 star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
1578 star_of_less_number <-- hypreal_of_real_less_number_of_iff
1579 star_of_le_number <-- hypreal_of_real_le_number_of_iff
1580 star_of_power <-- hypreal_of_real_power
1581 star_of_eq_0 <-- hcomplex_of_complex_zero_iff
1583 * Hyperreal: new method "transfer" that implements the transfer
1584 principle of nonstandard analysis. With a subgoal that mentions
1585 nonstandard types like "'a star", the command "apply transfer"
1586 replaces it with an equivalent one that mentions only standard types.
1587 To be successful, all free variables must have standard types; non-
1588 standard variables must have explicit universal quantifiers.
1590 * Hyperreal: A theory of Taylor series.
1595 * Discontinued special version of 'constdefs' (which used to support
1596 continuous functions) in favor of the general Pure one with full
1597 type-inference.
1599 * New simplification procedure for solving continuity conditions; it
1600 is much faster on terms with many nested lambda abstractions (cubic
1601 instead of exponential time).
1603 * New syntax for domain package: selector names are now optional.
1604 Parentheses should be omitted unless argument is lazy, for example:
1606 domain 'a stream = cons "'a" (lazy "'a stream")
1608 * New command 'fixrec' for defining recursive functions with pattern
1609 matching; defining multiple functions with mutual recursion is also
1610 supported. Patterns may include the constants cpair, spair, up, sinl,
1611 sinr, or any data constructor defined by the domain package. The given
1612 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
1613 syntax and examples.
1615 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
1616 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
1617 but the proof obligation additionally includes an admissibility
1618 requirement. The packages generate instances of class cpo or pcpo,
1619 with continuity and strictness theorems for Rep and Abs.
1621 * HOLCF: Many theorems have been renamed according to a more standard naming
1622 scheme (INCOMPATIBILITY):
1624 foo_inject: "foo$x = foo$y ==> x = y"
1625 foo_eq: "(foo$x = foo$y) = (x = y)"
1626 foo_less: "(foo$x << foo$y) = (x << y)"
1627 foo_strict: "foo$UU = UU"
1628 foo_defined: "... ==> foo$x ~= UU"
1629 foo_defined_iff: "(foo$x = UU) = (x = UU)"
1634 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
1635 including the First Isomorphism Theorem (on quotienting by the kernel
1636 of a homomorphism).
1638 * ZF/Simplifier: install second copy of type solver that actually
1639 makes use of TC rules declared to Isar proof contexts (or locales);
1640 the old version is still required for ML proof scripts.
1643 *** Cube ***
1645 * Converted to Isar theory format; use locales instead of axiomatic
1646 theories.
1651 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
1652 for ||>, ||>>, |>>,
1654 * Pure/library.ML no longer defines its own option datatype, but uses
1655 that of the SML basis, which has constructors NONE and SOME instead of
1656 None and Some, as well as exception Option.Option instead of OPTION.
1657 The functions the, if_none, is_some, is_none have been adapted
1658 accordingly, while Option.map replaces apsome.
1660 * Pure/library.ML: the exception LIST has been given up in favour of
1661 the standard exceptions Empty and Subscript, as well as
1662 Library.UnequalLengths. Function like Library.hd and Library.tl are
1663 superceded by the standard hd and tl functions etc.
1665 A number of basic list functions are no longer exported to the ML
1666 toplevel, as they are variants of predefined functions. The following
1667 suggests how one can translate existing code:
1669 rev_append xs ys = List.revAppend (xs, ys)
1670 nth_elem (i, xs) = List.nth (xs, i)
1671 last_elem xs = List.last xs
1672 flat xss = List.concat xss
1673 seq fs = List.app fs
1674 partition P xs = List.partition P xs
1675 mapfilter f xs = List.mapPartial f xs
1677 * Pure/library.ML: several combinators for linear functional
1678 transformations, notably reverse application and composition:
1680 x |> f f #> g
1681 (x, y) |-> f f #-> g
1683 * Pure/library.ML: introduced/changed precedence of infix operators:
1685 infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
1686 infix 2 ?;
1687 infix 3 o oo ooo oooo;
1688 infix 4 ~~ upto downto;
1690 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
1691 infix operators.
1693 * Pure/library.ML: natural list combinators fold, fold_rev, and
1694 fold_map support linear functional transformations and nesting. For
1695 example:
1697 fold f [x1, ..., xN] y =
1698 y |> f x1 |> ... |> f xN
1700 (fold o fold) f [xs1, ..., xsN] y =
1701 y |> fold f xs1 |> ... |> fold f xsN
1703 fold f [x1, ..., xN] =
1704 f x1 #> ... #> f xN
1706 (fold o fold) f [xs1, ..., xsN] =
1707 fold f xs1 #> ... #> fold f xsN
1709 * Pure/library.ML: the following selectors on type 'a option are
1710 available:
1712 the: 'a option -> 'a (*partial*)
1713 these: 'a option -> 'a where 'a = 'b list
1714 the_default: 'a -> 'a option -> 'a
1715 the_list: 'a option -> 'a list
1717 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
1718 basic operations for association lists, following natural argument
1719 order; moreover the explicit equality predicate passed here avoids
1720 potentially expensive polymorphic runtime equality checks.
1721 The old functions may be expressed as follows:
1723 assoc = uncurry (AList.lookup (op =))
1724 assocs = these oo AList.lookup (op =)
1725 overwrite = uncurry (AList.update (op =)) o swap
1727 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
1729 val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
1730 val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
1732 replacing make_keylist and keyfilter (occassionally used)
1733 Naive rewrites:
1735 make_keylist = AList.make
1736 keyfilter = AList.find (op =)
1738 * eq_fst and eq_snd now take explicit equality parameter, thus
1739 avoiding eqtypes. Naive rewrites:
1741 eq_fst = eq_fst (op =)
1742 eq_snd = eq_snd (op =)
1744 * Removed deprecated apl and apr (rarely used).
1745 Naive rewrites:
1747 apl (n, op) =>>= curry op n
1748 apr (op, m) =>>= fn n => op (n, m)
1750 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
1751 provides a reasonably efficient light-weight implementation of sets as
1752 lists.
1754 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
1755 few new operations; existing lookup and update are now curried to
1756 follow natural argument order (for use with fold etc.);
1757 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
1759 * Pure/General: output via the Isabelle channels of
1760 writeln/warning/error etc. is now passed through Output.output, with a
1761 hook for arbitrary transformations depending on the print_mode
1762 (cf. Output.add_mode -- the first active mode that provides a output
1763 function wins). Already formatted output may be embedded into further
1764 text via Output.raw; the result of Pretty.string_of/str_of and derived
1765 functions (string_of_term/cterm/thm etc.) is already marked raw to
1766 accommodate easy composition of diagnostic messages etc. Programmers
1767 rarely need to care about Output.output or Output.raw at all, with
1768 some notable exceptions: Output.output is required when bypassing the
1769 standard channels (writeln etc.), or in token translations to produce
1770 properly formatted results; Output.raw is required when capturing
1771 already output material that will eventually be presented to the user
1772 a second time. For the default print mode, both Output.output and
1773 Output.raw have no effect.
1775 * Pure/General: Output.time_accumulator NAME creates an operator ('a
1776 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
1777 cumulative results are displayed at the end of a batch session.
1779 * Pure/General: File.sysify_path and File.quote_sysify path have been
1780 replaced by File.platform_path and File.shell_path (with appropriate
1781 hooks). This provides a clean interface for unusual systems where the
1782 internal and external process view of file names are different.
1784 * Pure: more efficient orders for basic syntactic entities: added
1785 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
1786 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
1787 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
1788 orders now -- potential INCOMPATIBILITY for code that depends on a
1789 particular order for Symtab.keys, Symtab.dest, etc. (consider using
1790 Library.sort_strings on result).
1792 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
1793 fold_types traverse types/terms from left to right, observing natural
1794 argument order. Supercedes previous foldl_XXX versions, add_frees,
1795 add_vars etc. have been adapted as well: INCOMPATIBILITY.
1797 * Pure: name spaces have been refined, with significant changes of the
1798 internal interfaces -- INCOMPATIBILITY. Renamed cond_extern(_table)
1799 to extern(_table). The plain name entry path is superceded by a
1800 general 'naming' context, which also includes the 'policy' to produce
1801 a fully qualified name and external accesses of a fully qualified
1802 name; NameSpace.extend is superceded by context dependent
1803 Sign.declare_name. Several theory and proof context operations modify
1804 the naming context. Especially note Theory.restore_naming and
1805 ProofContext.restore_naming to get back to a sane state; note that
1806 Theory.add_path is no longer sufficient to recover from
1807 Theory.absolute_path in particular.
1809 * Pure: new flags short_names (default false) and unique_names
1810 (default true) for controlling output of qualified names. If
1811 short_names is set, names are printed unqualified. If unique_names is
1812 reset, the name prefix is reduced to the minimum required to achieve
1813 the original result when interning again, even if there is an overlap
1814 with earlier declarations.
1816 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
1817 now 'extend', and 'merge' gets an additional Pretty.pp argument
1818 (useful for printing error messages). INCOMPATIBILITY.
1820 * Pure: major reorganization of the theory context. Type Sign.sg and
1821 Theory.theory are now identified, referring to the universal
1822 Context.theory (see Pure/context.ML). Actual signature and theory
1823 content is managed as theory data. The old code and interfaces were
1824 spread over many files and structures; the new arrangement introduces
1825 considerable INCOMPATIBILITY to gain more clarity:
1827 Context -- theory management operations (name, identity, inclusion,
1828 parents, ancestors, merge, etc.), plus generic theory data;
1830 Sign -- logical signature and syntax operations (declaring consts,
1831 types, etc.), plus certify/read for common entities;
1833 Theory -- logical theory operations (stating axioms, definitions,
1834 oracles), plus a copy of logical signature operations (consts,
1835 types, etc.); also a few basic management operations (Theory.copy,
1836 Theory.merge, etc.)
1838 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
1839 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
1840 for convenience -- they merely return the theory.
1842 * Pure: type Type.tsig is superceded by theory in most interfaces.
1844 * Pure: the Isar proof context type is already defined early in Pure
1845 as Context.proof (note that ProofContext.context and Proof.context are
1846 aliases, where the latter is the preferred name). This enables other
1847 Isabelle components to refer to that type even before Isar is present.
1849 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
1850 typeK, constK, axiomK, oracleK), but provide explicit operations for
1851 any of these kinds. For example, Sign.intern typeK is now
1852 Sign.intern_type, Theory.hide_space Sign.typeK is now
1853 Theory.hide_types. Also note that former
1854 Theory.hide_classes/types/consts are now
1855 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
1856 internalize their arguments! INCOMPATIBILITY.
1858 * Pure: get_thm interface (of PureThy and ProofContext) expects
1859 datatype thmref (with constructors Name and NameSelection) instead of
1860 plain string -- INCOMPATIBILITY;
1862 * Pure: cases produced by proof methods specify options, where NONE
1863 means to remove case bindings -- INCOMPATIBILITY in
1866 * Pure: the following operations retrieve axioms or theorems from a
1867 theory node or theory hierarchy, respectively:
1869 Theory.axioms_of: theory -> (string * term) list
1870 Theory.all_axioms_of: theory -> (string * term) list
1871 PureThy.thms_of: theory -> (string * thm) list
1872 PureThy.all_thms_of: theory -> (string * thm) list
1874 * Pure: print_tac now outputs the goal through the trace channel.
1876 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
1877 Reference Toplevel.debug (default false) controls detailed printing
1878 and tracing of low-level exceptions; Toplevel.profiling (default 0)
1879 controls execution profiling -- set to 1 for time and 2 for space
1880 (both increase the runtime).
1882 * Isar session: The initial use of ROOT.ML is now always timed,
1883 i.e. the log will show the actual process times, in contrast to the
1884 elapsed wall-clock time that the outer shell wrapper produces.
1886 * Simplifier: improved handling of bound variables (nameless
1887 representation, avoid allocating new strings). Simprocs that invoke
1888 the Simplifier recursively should use Simplifier.inherit_bounds to
1889 avoid local name clashes. Failure to do so produces warnings
1890 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
1891 for further details.
1893 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
1894 bindings for all theorems stored within a given theory; this may help
1895 in porting non-Isar theories to Isar ones, while keeping ML proof
1896 scripts for the time being.
1898 * ML operator HTML.with_charset specifies the charset begin used for
1899 generated HTML files. For example:
1901 HTML.with_charset "utf-8" use_thy "Hebrew";
1902 HTML.with_charset "utf-8" use_thy "Chinese";
1905 *** System ***
1907 * Allow symlinks to all proper Isabelle executables (Isabelle,
1908 isabelle, isatool etc.).
1910 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
1911 isatool doc, isatool mkdir, display_drafts etc.).
1913 * isatool usedir: option -f allows specification of the ML file to be
1914 used by Isabelle; default is ROOT.ML.
1916 * New isatool version outputs the version identifier of the Isabelle
1917 distribution being used.
1919 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
1920 (containing Boolean satisfiability problems) into Isabelle/HOL
1921 theories.
1925 New in Isabelle2004 (April 2004)
1926 --------------------------------
1928 *** General ***
1930 * Provers/order.ML: new efficient reasoner for partial and linear orders.
1931 Replaces linorder.ML.
1933 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
1934 (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
1935 (\<a>...\<z>), are now considered normal letters, and can therefore
1936 be used anywhere where an ASCII letter (a...zA...Z) has until
1937 now. COMPATIBILITY: This obviously changes the parsing of some
1938 terms, especially where a symbol has been used as a binder, say
1939 '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
1940 as an identifier. Fix it by inserting a space around former
1941 symbols. Call 'isatool fixgreek' to try to fix parsing errors in
1942 existing theory and ML files.
1944 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
1946 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
1947 allowed in identifiers. Similar to Greek letters \<^isub> is now considered
1948 a normal (but invisible) letter. For multiple letter subscripts repeat
1949 \<^isub> like this: x\<^isub>1\<^isub>2.
1951 * Pure: There are now sub-/superscripts that can span more than one
1952 character. Text between \<^bsub> and \<^esub> is set in subscript in
1953 ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
1954 superscript. The new control characters are not identifier parts.
1956 * Pure: Control-symbols of the form \<^raw:...> will literally print the
1957 content of "..." to the latex file instead of \isacntrl... . The "..."
1958 may consist of any printable characters excluding the end bracket >.
1960 * Pure: Using new Isar command "finalconsts" (or the ML functions
1961 Theory.add_finals or Theory.add_finals_i) it is now possible to
1962 declare constants "final", which prevents their being given a definition
1963 later. It is useful for constants whose behaviour is fixed axiomatically
1964 rather than definitionally, such as the meta-logic connectives.
1966 * Pure: 'instance' now handles general arities with general sorts
1967 (i.e. intersections of classes),
1969 * Presentation: generated HTML now uses a CSS style sheet to make layout
1970 (somewhat) independent of content. It is copied from lib/html/isabelle.css.
1971 It can be changed to alter the colors/layout of generated pages.
1974 *** Isar ***
1976 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
1977 cut_tac, subgoal_tac and thin_tac:
1978 - Now understand static (Isar) contexts. As a consequence, users of Isar
1979 locales are no longer forced to write Isar proof scripts.
1980 For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
1981 emulations.
1982 - INCOMPATIBILITY: names of variables to be instantiated may no
1983 longer be enclosed in quotes. Instead, precede variable name with `?'.
1984 This is consistent with the instantiation attribute "where".
1986 * Attributes "where" and "of":
1987 - Now take type variables of instantiated theorem into account when reading
1988 the instantiation string. This fixes a bug that caused instantiated
1989 theorems to have too special types in some circumstances.
1990 - "where" permits explicit instantiations of type variables.
1992 * Calculation commands "moreover" and "also" no longer interfere with
1993 current facts ("this"), admitting arbitrary combinations with "then"
1994 and derived forms.
1996 * Locales:
1997 - Goal statements involving the context element "includes" no longer
1998 generate theorems with internal delta predicates (those ending on
1999 "_axioms") in the premise.
2000 Resolve particular premise with <locale>.intro to obtain old form.
2001 - Fixed bug in type inference ("unify_frozen") that prevented mix of target
2002 specification and "includes" elements in goal statement.
2003 - Rule sets <locale>.intro and <locale>.axioms no longer declared as
2004 [intro?] and [elim?] (respectively) by default.
2005 - Experimental command for instantiation of locales in proof contexts:
2006 instantiate <label>[<attrs>]: <loc>
2007 Instantiates locale <loc> and adds all its theorems to the current context
2008 taking into account their attributes. Label and attrs are optional
2009 modifiers, like in theorem declarations. If present, names of
2010 instantiated theorems are qualified with <label>, and the attributes
2011 <attrs> are applied after any attributes these theorems might have already.
2012 If the locale has assumptions, a chained fact of the form
2013 "<loc> t1 ... tn" is expected from which instantiations of the parameters
2014 are derived. The command does not support old-style locales declared
2015 with "locale (open)".
2016 A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
2018 * HOL: Tactic emulation methods induct_tac and case_tac understand static
2019 (Isar) contexts.
2024 * Proof import: new image HOL4 contains the imported library from
2025 the HOL4 system with about 2500 theorems. It is imported by
2026 replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
2027 can be used like any other Isabelle image. See
2028 HOL/Import/HOL/README for more information.
2030 * Simplifier:
2031 - Much improved handling of linear and partial orders.
2032 Reasoners for linear and partial orders are set up for type classes
2033 "linorder" and "order" respectively, and are added to the default simpset
2034 as solvers. This means that the simplifier can build transitivity chains
2035 to solve goals from the assumptions.
2036 - INCOMPATIBILITY: old proofs break occasionally. Typically, applications
2037 of blast or auto after simplification become unnecessary because the goal
2038 is solved by simplification already.
2040 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
2041 all proved in axiomatic type classes for semirings, rings and fields.
2043 * Numerics:
2044 - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
2045 now formalized using the Ring_and_Field theory mentioned above.
2046 - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
2047 than before, because now they are set up once in a generic manner.
2048 - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
2049 Look for the general versions in Ring_and_Field (and Power if they concern
2050 exponentiation).
2052 * Type "rat" of the rational numbers is now available in HOL-Complex.
2054 * Records:
2055 - Record types are now by default printed with their type abbreviation
2056 instead of the list of all field types. This can be configured via
2057 the reference "print_record_type_abbr".
2058 - Simproc "record_upd_simproc" for simplification of multiple updates added
2059 (not enabled by default).
2060 - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
2061 EX x. x = sel r to True (not enabled by default).
2062 - Tactic "record_split_simp_tac" to split and simplify records added.
2064 * 'specification' command added, allowing for definition by
2065 specification. There is also an 'ax_specification' command that
2066 introduces the new constants axiomatically.
2068 * arith(_tac) is now able to generate counterexamples for reals as well.
2070 * HOL-Algebra: new locale "ring" for non-commutative rings.
2072 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
2073 definitions, thanks to Sava Krsti\'{c} and John Matthews.
2075 * HOL-Matrix: a first theory for matrices in HOL with an application of
2076 matrix theory to linear programming.
2078 * Unions and Intersections:
2079 The latex output syntax of UN and INT has been changed
2080 from "\Union x \in A. B" to "\Union_{x \in A} B"
2081 i.e. the index formulae has become a subscript.
2082 Similarly for "\Union x. B", and for \Inter instead of \Union.
2084 * Unions and Intersections over Intervals:
2085 There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
2086 also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
2087 like in normal math, and corresponding versions for < and for intersection.
2089 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
2090 lexicographic dictonary ordering has been added as "lexord".
2092 * ML: the legacy theory structures Int and List have been removed. They had
2093 conflicted with ML Basis Library structures having the same names.
2095 * 'refute' command added to search for (finite) countermodels. Only works
2096 for a fragment of HOL. The installation of an external SAT solver is
2097 highly recommended. See "HOL/Refute.thy" for details.
2099 * 'quickcheck' command: Allows to find counterexamples by evaluating
2100 formulae under an assignment of free variables to random values.
2101 In contrast to 'refute', it can deal with inductive datatypes,
2102 but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
2103 for examples.
2108 * Streams now come with concatenation and are part of the HOLCF image
2112 New in Isabelle2003 (May 2003)
2113 ------------------------------
2115 *** General ***
2117 * Provers/simplifier:
2119 - Completely reimplemented method simp (ML: Asm_full_simp_tac):
2120 Assumptions are now subject to complete mutual simplification,
2121 not just from left to right. The simplifier now preserves
2122 the order of assumptions.
2124 Potential INCOMPATIBILITY:
2126 -- simp sometimes diverges where the old version did
2127 not, e.g. invoking simp on the goal
2129 [| P (f x); y = x; f x = f y |] ==> Q
2131 now gives rise to the infinite reduction sequence
2133 P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
2135 Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
2136 kind of problem.
2138 -- Tactics combining classical reasoner and simplification (such as auto)
2139 are also affected by this change, because many of them rely on
2140 simp. They may sometimes diverge as well or yield a different numbers
2141 of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
2142 in case of problems. Sometimes subsequent calls to the classical
2143 reasoner will fail because a preceeding call to the simplifier too
2144 eagerly simplified the goal, e.g. deleted redundant premises.
2146 - The simplifier trace now shows the names of the applied rewrite rules
2148 - You can limit the number of recursive invocations of the simplifier
2149 during conditional rewriting (where the simplifie tries to solve the
2150 conditions before applying the rewrite rule):
2151 ML "simp_depth_limit := n"
2152 where n is an integer. Thus you can force termination where previously
2153 the simplifier would diverge.
2155 - Accepts free variables as head terms in congruence rules. Useful in Isar.
2157 - No longer aborts on failed congruence proof. Instead, the
2158 congruence is ignored.
2160 * Pure: New generic framework for extracting programs from constructive
2161 proofs. See HOL/Extraction.thy for an example instantiation, as well
2162 as HOL/Extraction for some case studies.
2164 * Pure: The main goal of the proof state is no longer shown by default, only
2165 the subgoals. This behaviour is controlled by a new flag.
2166 PG menu: Isabelle/Isar -> Settings -> Show Main Goal
2167 (ML: Proof.show_main_goal).
2169 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
2170 rules whose conclusion matches subgoal 1:
2171 PG menu: Isabelle/Isar -> Show me -> matching rules
2172 The rules are ordered by how closely they match the subgoal.
2173 In particular, rules that solve a subgoal outright are displayed first
2174 (or rather last, the way they are printed).
2175 (ML: ProofGeneral.print_intros())
2177 * Pure: New flag trace_unify_fail causes unification to print
2178 diagnostic information (PG: in trace buffer) when it fails. This is
2179 useful for figuring out why single step proofs like rule, erule or
2180 assumption failed.
2182 * Pure: Locale specifications now produce predicate definitions
2183 according to the body of text (covering assumptions modulo local
2184 definitions); predicate "loc_axioms" covers newly introduced text,
2185 while "loc" is cumulative wrt. all included locale expressions; the
2186 latter view is presented only on export into the global theory
2187 context; potential INCOMPATIBILITY, use "(open)" option to fall back
2188 on the old view without predicates;
2190 * Pure: predefined locales "var" and "struct" are useful for sharing
2191 parameters (as in CASL, for example); just specify something like
2192 ``var x + var y + struct M'' as import;
2194 * Pure: improved thms_containing: proper indexing of facts instead of
2195 raw theorems; check validity of results wrt. current name space;
2196 include local facts of proof configuration (also covers active
2197 locales), cover fixed variables in index; may use "_" in term
2198 specification; an optional limit for the number of printed facts may
2199 be given (the default is 40);
2201 * Pure: disallow duplicate fact bindings within new-style theory files
2202 (batch-mode only);
2204 * Provers: improved induct method: assumptions introduced by case
2205 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
2206 the goal statement); "foo" still refers to all facts collectively;
2208 * Provers: the function blast.overloaded has been removed: all constants
2209 are regarded as potentially overloaded, which improves robustness in exchange
2210 for slight decrease in efficiency;
2212 * Provers/linorder: New generic prover for transitivity reasoning over
2213 linear orders. Note: this prover is not efficient!
2215 * Isar: preview of problems to finish 'show' now produce an error
2216 rather than just a warning (in interactive mode);
2221 * arith(_tac)
2223 - Produces a counter example if it cannot prove a goal.
2224 Note that the counter example may be spurious if the goal is not a formula
2225 of quantifier-free linear arithmetic.
2226 In ProofGeneral the counter example appears in the trace buffer.
2228 - Knows about div k and mod k where k is a numeral of type nat or int.
2230 - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
2231 linear arithmetic fails. This takes account of quantifiers and divisibility.
2232 Presburger arithmetic can also be called explicitly via presburger(_tac).
2234 * simp's arithmetic capabilities have been enhanced a bit: it now
2235 takes ~= in premises into account (by performing a case split);
2237 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
2238 are distributed over a sum of terms;
2240 * New tactic "trans_tac" and method "trans" instantiate
2241 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
2242 "<=", "<" and "=").
2244 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
2245 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
2247 * 'typedef' command has new option "open" to suppress the set
2248 definition;
2250 * functions Min and Max on finite sets have been introduced (theory
2251 Finite_Set);
2253 * attribute [symmetric] now works for relations as well; it turns
2254 (x,y) : R^-1 into (y,x) : R, and vice versa;
2256 * induct over a !!-quantified statement (say !!x1..xn):
2257 each "case" automatically performs "fix x1 .. xn" with exactly those names.
2259 * Map: `empty' is no longer a constant but a syntactic abbreviation for
2260 %x. None. Warning: empty_def now refers to the previously hidden definition
2261 of the empty set.
2263 * Algebra: formalization of classical algebra. Intended as base for
2264 any algebraic development in Isabelle. Currently covers group theory
2265 (up to Sylow's theorem) and ring theory (Universal Property of
2266 Univariate Polynomials). Contributions welcome;
2268 * GroupTheory: deleted, since its material has been moved to Algebra;
2270 * Complex: new directory of the complex numbers with numeric constants,
2271 nonstandard complex numbers, and some complex analysis, standard and
2272 nonstandard (Jacques Fleuriot);
2274 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
2276 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
2277 Fleuriot);
2279 * Real/HahnBanach: updated and adapted to locales;
2281 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
2282 Gray and Kramer);
2284 * UNITY: added the Meier-Sanders theory of progress sets;
2286 * MicroJava: bytecode verifier and lightweight bytecode verifier
2287 as abstract algorithms, instantiated to the JVM;
2289 * Bali: Java source language formalization. Type system, operational
2290 semantics, axiomatic semantics. Supported language features:
2291 classes, interfaces, objects,virtual methods, static methods,
2292 static/instance fields, arrays, access modifiers, definite
2293 assignment, exceptions.
2298 * ZF/Constructible: consistency proof for AC (Gdel's constructible
2299 universe, etc.);
2301 * Main ZF: virtually all theories converted to new-style format;
2306 * Pure: Tactic.prove provides sane interface for internal proofs;
2307 omits the infamous "standard" operation, so this is more appropriate
2308 than prove_goalw_cterm in many situations (e.g. in simprocs);
2310 * Pure: improved error reporting of simprocs;
2312 * Provers: Simplifier.simproc(_i) provides sane interface for setting
2313 up simprocs;
2316 *** Document preparation ***
2318 * uses \par instead of \\ for line breaks in theory text. This may
2319 shift some page breaks in large documents. To get the old behaviour
2320 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
2322 * minimized dependencies of isabelle.sty and isabellesym.sty on
2323 other packages
2325 * \<euro> now needs package babel/greek instead of marvosym (which
2326 broke \Rightarrow)
2328 * normal size for \<zero>...\<nine> (uses \mathbf instead of
2329 textcomp package)
2333 New in Isabelle2002 (March 2002)
2334 --------------------------------
2336 *** Document preparation ***
2338 * greatly simplified document preparation setup, including more
2339 graceful interpretation of isatool usedir -i/-d/-D options, and more
2340 instructive isatool mkdir; users should basically be able to get
2341 started with "isatool mkdir HOL Test && isatool make"; alternatively,
2342 users may run a separate document processing stage manually like this:
2343 "isatool usedir -D output HOL Test && isatool document Test/output";
2345 * theory dependency graph may now be incorporated into documents;
2346 isatool usedir -g true will produce session_graph.eps/.pdf for use
2347 with \includegraphics of LaTeX;
2349 * proper spacing of consecutive markup elements, especially text
2350 blocks after section headings;
2352 * support bold style (for single symbols only), input syntax is like
2353 this: "\<^bold>\<alpha>" or "\<^bold>A";
2355 * \<bullet> is now output as bold \cdot by default, which looks much
2356 better in printed text;
2358 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
2359 note that these symbols are currently unavailable in Proof General /
2360 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
2362 * isatool latex no longer depends on changed TEXINPUTS, instead
2363 isatool document copies the Isabelle style files to the target
2364 location;
2367 *** Isar ***
2369 * Pure/Provers: improved proof by cases and induction;
2370 - 'case' command admits impromptu naming of parameters (such as
2371 "case (Suc n)");
2372 - 'induct' method divinates rule instantiation from the inductive
2373 claim; no longer requires excessive ?P bindings for proper
2374 instantiation of cases;
2375 - 'induct' method properly enumerates all possibilities of set/type
2376 rules; as a consequence facts may be also passed through *type*
2377 rules without further ado;
2378 - 'induct' method now derives symbolic cases from the *rulified*
2379 rule (before it used to rulify cases stemming from the internal
2380 atomized version); this means that the context of a non-atomic
2381 statement becomes is included in the hypothesis, avoiding the
2382 slightly cumbersome show "PROP ?case" form;
2383 - 'induct' may now use elim-style induction rules without chaining
2384 facts, using ``missing'' premises from the goal state; this allows
2385 rules stemming from inductive sets to be applied in unstructured
2386 scripts, while still benefitting from proper handling of non-atomic
2387 statements; NB: major inductive premises need to be put first, all
2388 the rest of the goal is passed through the induction;
2389 - 'induct' proper support for mutual induction involving non-atomic
2390 rule statements (uses the new concept of simultaneous goals, see
2391 below);
2392 - append all possible rule selections, but only use the first
2393 success (no backtracking);
2394 - removed obsolete "(simplified)" and "(stripped)" options of methods;
2395 - undeclared rule case names default to numbers 1, 2, 3, ...;
2396 - added 'print_induct_rules' (covered by help item in recent Proof
2397 General versions);
2398 - moved induct/cases attributes to Pure, methods to Provers;
2399 - generic method setup instantiated for FOL and HOL;
2401 * Pure: support multiple simultaneous goal statements, for example
2402 "have a: A and b: B" (same for 'theorem' etc.); being a pure
2403 meta-level mechanism, this acts as if several individual goals had
2404 been stated separately; in particular common proof methods need to be
2405 repeated in order to cover all claims; note that a single elimination
2406 step is *not* sufficient to establish the two conjunctions, so this
2407 fails:
2409 assume "A & B" then have A and B .. (*".." fails*)
2411 better use "obtain" in situations as above; alternative refer to
2412 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
2414 * Pure: proper integration with ``locales''; unlike the original
2415 version by Florian Kammller, Isar locales package high-level proof
2416 contexts rather than raw logical ones (e.g. we admit to include
2417 attributes everywhere); operations on locales include merge and
2418 rename; support for implicit arguments (``structures''); simultaneous
2419 type-inference over imports and text; see also HOL/ex/Locales.thy for
2420 some examples;
2422 * Pure: the following commands have been ``localized'', supporting a
2423 target locale specification "(in name)": 'lemma', 'theorem',
2424 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
2425 stored both within the locale and at the theory level (exported and
2426 qualified by the locale name);
2428 * Pure: theory goals may now be specified in ``long'' form, with
2429 ad-hoc contexts consisting of arbitrary locale elements. for example
2430 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
2431 definitions may be given, too); the result is a meta-level rule with
2432 the context elements being discharged in the obvious way;
2434 * Pure: new proof command 'using' allows to augment currently used
2435 facts after a goal statement ('using' is syntactically analogous to
2436 'apply', but acts on the goal's facts only); this allows chained facts
2437 to be separated into parts given before and after a claim, as in
2438 ``from a and b have C using d and e <proof>'';
2440 * Pure: renamed "antecedent" case to "rule_context";
2442 * Pure: new 'judgment' command records explicit information about the
2443 object-logic embedding (used by several tools internally); no longer
2444 use hard-wired "Trueprop";
2446 * Pure: added 'corollary' command;
2448 * Pure: fixed 'token_translation' command;
2450 * Pure: removed obsolete 'exported' attribute;
2452 * Pure: dummy pattern "_" in is/let is now automatically lifted over
2453 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
2454 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
2456 * Pure: method 'atomize' presents local goal premises as object-level
2457 statements (atomic meta-level propositions); setup controlled via
2458 rewrite rules declarations of 'atomize' attribute; example
2459 application: 'induct' method with proper rule statements in improper
2460 proof *scripts*;
2462 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
2463 now consider the syntactic context of assumptions, giving a better
2464 chance to get type-inference of the arguments right (this is
2465 especially important for locales);
2467 * Pure: "sorry" no longer requires quick_and_dirty in interactive
2468 mode;
2470 * Pure/obtain: the formal conclusion "thesis", being marked as
2471 ``internal'', may no longer be reference directly in the text;
2472 potential INCOMPATIBILITY, may need to use "?thesis" in rare
2473 situations;
2475 * Pure: generic 'sym' attribute which declares a rule both as pure
2476 'elim?' and for the 'symmetric' operation;
2478 * Pure: marginal comments ``--'' may now occur just anywhere in the
2479 text; the fixed correlation with particular command syntax has been
2480 discontinued;
2482 * Pure: new method 'rules' is particularly well-suited for proof
2483 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
2484 but often produces more compact proof terms with less detours;
2486 * Pure/Provers/classical: simplified integration with pure rule
2487 attributes and methods; the classical "intro?/elim?/dest?"
2488 declarations coincide with the pure ones; the "rule" method no longer
2489 includes classically swapped intros; "intro" and "elim" methods no
2490 longer pick rules from the context; also got rid of ML declarations
2491 AddXIs/AddXEs/AddXDs; all of this has some potential for
2494 * Provers/classical: attribute 'swapped' produces classical inversions
2495 of introduction rules;
2497 * Provers/simplifier: 'simplified' attribute may refer to explicit
2498 rules instead of full simplifier context; 'iff' attribute handles
2499 conditional rules;
2501 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
2503 * HOL: 'recdef' now fails on unfinished automated proofs, use
2504 "(permissive)" option to recover old behavior;
2506 * HOL: 'inductive' no longer features separate (collective) attributes
2507 for 'intros' (was found too confusing);
2509 * HOL: properly declared induction rules less_induct and
2510 wf_induct_rule;
2515 * HOL: moved over to sane numeral syntax; the new policy is as
2516 follows:
2518 - 0 and 1 are polymorphic constants, which are defined on any
2519 numeric type (nat, int, real etc.);
2521 - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
2522 binary representation internally;
2524 - type nat has special constructor Suc, and generally prefers Suc 0
2525 over 1::nat and Suc (Suc 0) over 2::nat;
2527 This change may cause significant problems of INCOMPATIBILITY; here
2528 are some hints on converting existing sources:
2530 - due to the new "num" token, "-0" and "-1" etc. are now atomic
2531 entities, so expressions involving "-" (unary or binary minus) need
2532 to be spaced properly;
2534 - existing occurrences of "1" may need to be constraint "1::nat" or
2535 even replaced by Suc 0; similar for old "2";
2537 - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
2539 - remove all special provisions on numerals in proofs;
2541 * HOL: simp rules nat_number expand numerals on nat to Suc/0
2542 representation (depends on bin_arith_simps in the default context);
2544 * HOL: symbolic syntax for x^2 (numeral 2);
2546 * HOL: the class of all HOL types is now called "type" rather than
2547 "term"; INCOMPATIBILITY, need to adapt references to this type class
2548 in axclass/classes, instance/arities, and (usually rare) occurrences
2549 in typings (of consts etc.); internally the class is called
2550 "HOL.type", ML programs should refer to HOLogic.typeS;
2552 * HOL/record package improvements:
2553 - new derived operations "fields" to build a partial record section,
2554 "extend" to promote a fixed record to a record scheme, and
2555 "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
2556 declared as simp by default;
2557 - shared operations ("more", "fields", etc.) now need to be always
2558 qualified) --- potential INCOMPATIBILITY;
2559 - removed "make_scheme" operations (use "make" with "extend") --
2561 - removed "more" class (simply use "term") -- INCOMPATIBILITY;
2562 - provides cases/induct rules for use with corresponding Isar
2563 methods (for concrete records, record schemes, concrete more
2564 parts, and schematic more parts -- in that order);
2565 - internal definitions directly based on a light-weight abstract
2566 theory of product types over typedef rather than datatype;
2568 * HOL: generic code generator for generating executable ML code from
2569 specifications; specific support for HOL constructs such as inductive
2570 datatypes and sets, as well as recursive functions; can be invoked
2571 via 'generate_code' theory section;
2573 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
2575 * HOL: consolidated and renamed several theories. In particular:
2576 Ord.thy has been absorbed into HOL.thy
2577 String.thy has been absorbed into List.thy
2579 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
2580 (beware of argument permutation!);
2582 * HOL: linorder_less_split superseded by linorder_cases;
2584 * HOL/List: "nodups" renamed to "distinct";
2586 * HOL: added "The" definite description operator; move Hilbert's "Eps"
2587 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
2588 - Ex_def has changed, now need to use some_eq_ex
2590 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
2591 in this (rare) case use:
2593 delSWrapper "split_all_tac"
2594 addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
2596 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
2599 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
2600 Isabelle's type classes, ^ on functions and relations has too general
2601 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
2602 necessary to attach explicit type constraints;
2604 * HOL/Relation: the prefix name of the infix "O" has been changed from
2605 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
2606 renamed accordingly (eg "compI" -> "rel_compI").
2608 * HOL: syntax translations now work properly with numerals and records
2609 expressions;
2611 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
2612 of "lam" -- INCOMPATIBILITY;
2614 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
2615 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
2616 renamed "Product_Type.unit";
2618 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
2620 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
2621 the "cases" method);
2623 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
2624 Florian Kammller);
2626 * HOL/IMP: updated and converted to new-style theory format; several
2627 parts turned into readable document, with proper Isar proof texts and
2628 some explanations (by Gerwin Klein);
2630 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
2632 * HOL-Hyperreal is now a logic image;
2637 * Isar: consts/constdefs supports mixfix syntax for continuous
2638 operations;
2640 * Isar: domain package adapted to new-style theory format, e.g. see
2641 HOLCF/ex/Dnat.thy;
2643 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
2644 potential INCOMPATIBILITY; now use plain induct_tac instead of former
2645 lift.induct_tac, always use UU instead of Undef;
2647 * HOLCF/IMP: updated and converted to new-style theory;
2652 * Isar: proper integration of logic-specific tools and packages,
2653 including theory commands '(co)inductive', '(co)datatype',
2654 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
2655 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
2657 * theory Main no longer includes AC; for the Axiom of Choice, base
2658 your theory on Main_ZFC;
2660 * the integer library now covers quotients and remainders, with many
2661 laws relating division to addition, multiplication, etc.;
2663 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
2664 typeless version of the formalism;
2666 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
2667 format;
2669 * ZF/Induct: new directory for examples of inductive definitions,
2670 including theory Multiset for multiset orderings; converted to
2671 new-style theory format;
2673 * ZF: many new theorems about lists, ordinals, etc.;
2676 *** General ***
2678 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
2679 variable proof controls level of detail: 0 = no proofs (only oracle
2680 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
2681 also ref manual for further ML interfaces;
2683 * Pure/axclass: removed obsolete ML interface
2684 goal_subclass/goal_arity;
2686 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
2687 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
2688 separate tokens, so expressions involving minus need to be spaced
2689 properly;
2691 * Pure/syntax: support non-oriented infixes, using keyword "infix"
2692 rather than "infixl" or "infixr";
2694 * Pure/syntax: concrete syntax for dummy type variables admits genuine
2695 sort constraint specifications in type inference; e.g. "x::_::foo"
2696 ensures that the type of "x" is of sort "foo" (but not necessarily a
2697 type variable);
2699 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
2700 control output of nested => (types); the default behavior is
2701 "type_brackets";
2703 * Pure/syntax: builtin parse translation for "_constify" turns valued
2704 tokens into AST constants;
2706 * Pure/syntax: prefer later declarations of translations and print
2707 translation functions; potential INCOMPATIBILITY: need to reverse
2708 multiple declarations for same syntax element constant;
2710 * Pure/show_hyps reset by default (in accordance to existing Isar
2711 practice);
2713 * Provers/classical: renamed addaltern to addafter, addSaltern to
2714 addSafter;
2716 * Provers/clasimp: ``iff'' declarations now handle conditional rules
2717 as well;
2719 * system: tested support for MacOS X; should be able to get Isabelle +
2720 Proof General to work in a plain Terminal after installing Poly/ML
2721 (e.g. from the Isabelle distribution area) and GNU bash alone
2722 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
2723 support requires further installations, e.g. from
2724 http://fink.sourceforge.net/);
2726 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
2728 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
2729 of 40 MB), cf. ML_OPTIONS;
2731 * system: Proof General keywords specification is now part of the
2732 Isabelle distribution (see etc/isar-keywords.el);
2734 * system: support for persistent Proof General sessions (refrain from
2735 outdating all loaded theories on startup); user may create writable
2736 logic images like this: ``isabelle -q HOL Test'';
2738 * system: smart selection of Isabelle process versus Isabelle
2739 interface, accommodates case-insensitive file systems (e.g. HFS+); may
2740 run both "isabelle" and "Isabelle" even if file names are badly
2741 damaged (executable inspects the case of the first letter of its own
2742 name); added separate "isabelle-process" and "isabelle-interface";
2744 * system: refrain from any attempt at filtering input streams; no
2745 longer support ``8bit'' encoding of old isabelle font, instead proper
2746 iso-latin characters may now be used; the related isatools
2747 "symbolinput" and "nonascii" have disappeared as well;
2749 * system: removed old "xterm" interface (the print modes "xterm" and
2750 "xterm_color" are still available for direct use in a suitable
2751 terminal);
2755 New in Isabelle99-2 (February 2001)
2756 -----------------------------------
2758 *** Overview of INCOMPATIBILITIES ***
2760 * HOL: please note that theories in the Library and elsewhere often use the
2761 new-style (Isar) format; to refer to their theorems in an ML script you must
2762 bind them to ML identifers by e.g. val thm_name = thm "thm_name";
2764 * HOL: inductive package no longer splits induction rule aggressively,
2765 but only as far as specified by the introductions given; the old
2766 format may be recovered via ML function complete_split_rule or attribute
2767 'split_rule (complete)';
2769 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
2770 gfp_Tarski to gfp_unfold;
2772 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
2774 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
2775 relation); infix "^^" has been renamed "``"; infix "``" has been
2776 renamed "`"; "univalent" has been renamed "single_valued";
2778 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
2779 operation;
2781 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
2783 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
2785 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
2786 consequence, it is no longer monotonic wrt. the local goal context
2787 (which is now passed through the inductive cases);
2789 * Document preparation: renamed standard symbols \<ll> to \<lless> and
2790 \<gg> to \<ggreater>;
2793 *** Document preparation ***
2795 * \isabellestyle{NAME} selects version of Isabelle output (currently
2796 available: are "it" for near math-mode best-style output, "sl" for
2797 slanted text style, and "tt" for plain type-writer; if no
2798 \isabellestyle command is given, output is according to slanted
2799 type-writer);
2801 * support sub/super scripts (for single symbols only), input syntax is
2802 like this: "A\<^sup>*" or "A\<^sup>\<star>";
2804 * some more standard symbols; see Appendix A of the system manual for
2805 the complete list of symbols defined in isabellesym.sty;
2807 * improved isabelle style files; more abstract symbol implementation
2808 (should now use \isamath{...} and \isatext{...} in custom symbol
2809 definitions);
2811 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
2812 state; Note that presentation of goal states does not conform to
2813 actual human-readable proof documents. Please do not include goal
2814 states into document output unless you really know what you are doing!
2816 * proper indentation of antiquoted output with proportional LaTeX
2817 fonts;
2819 * no_document ML operator temporarily disables LaTeX document
2820 generation;
2822 * isatool unsymbolize tunes sources for plain ASCII communication;
2825 *** Isar ***
2827 * Pure: Isar now suffers initial goal statements to contain unbound
2828 schematic variables (this does not conform to actual readable proof
2829 documents, due to unpredictable outcome and non-compositional proof
2830 checking); users who know what they are doing may use schematic goals
2831 for Prolog-style synthesis of proven results;
2833 * Pure: assumption method (an implicit finishing) now handles actual
2834 rules as well;
2836 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
2837 initial goal, declare "that" only as Pure intro (only for single
2838 steps); the "that" rule assumption may now be involved in implicit
2839 finishing, thus ".." becomes a feasible for trivial obtains;
2841 * Pure: default proof step now includes 'intro_classes'; thus trivial
2842 instance proofs may be performed by "..";
2844 * Pure: ?thesis / ?this / "..." now work for pure meta-level
2845 statements as well;
2847 * Pure: more robust selection of calculational rules;
2849 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
2850 rule (as well as the assumption rule);
2852 * Pure: 'thm_deps' command visualizes dependencies of theorems and
2853 lemmas, using the graph browser tool;
2855 * Pure: predict failure of "show" in interactive mode;
2857 * Pure: 'thms_containing' now takes actual terms as arguments;
2859 * HOL: improved method 'induct' --- now handles non-atomic goals
2860 (potential INCOMPATIBILITY); tuned error handling;
2862 * HOL: cases and induct rules now provide explicit hints about the
2863 number of facts to be consumed (0 for "type" and 1 for "set" rules);
2864 any remaining facts are inserted into the goal verbatim;
2866 * HOL: local contexts (aka cases) may now contain term bindings as
2867 well; the 'cases' and 'induct' methods new provide a ?case binding for
2868 the result to be shown in each case;
2870 * HOL: added 'recdef_tc' command;
2872 * isatool convert assists in eliminating legacy ML scripts;
2877 * HOL/Library: a collection of generic theories to be used together
2878 with main HOL; the theory loader path already includes this directory
2879 by default; the following existing theories have been moved here:
2880 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
2881 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
2883 * HOL/Unix: "Some aspects of Unix file-system security", a typical
2884 modelling and verification task performed in Isabelle/HOL +
2885 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
2887 * HOL/Algebra: special summation operator SUM no longer exists, it has
2888 been replaced by setsum; infix 'assoc' now has priority 50 (like
2889 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
2890 'domain', this makes the theory consistent with mathematical
2891 literature;
2893 * HOL basics: added overloaded operations "inverse" and "divide"
2894 (infix "/"), syntax for generic "abs" operation, generic summation
2895 operator \<Sum>;
2897 * HOL/typedef: simplified package, provide more useful rules (see also
2898 HOL/subset.thy);
2900 * HOL/datatype: induction rule for arbitrarily branching datatypes is
2901 now expressed as a proper nested rule (old-style tactic scripts may
2902 require atomize_strip_tac to cope with non-atomic premises);
2904 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
2905 to "split_conv" (old name still available for compatibility);
2907 * HOL: improved concrete syntax for strings (e.g. allows translation
2908 rules with string literals);
2910 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
2911 and Fleuriot's mechanization of analysis, including the transcendental
2912 functions for the reals;
2914 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
2919 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
2920 "lam" is displayed as TWO lambda-symbols
2922 * CTT: theory Main now available, containing everything (that is, Bool
2923 and Arith);
2926 *** General ***
2928 * Pure: the Simplifier has been implemented properly as a derived rule
2929 outside of the actual kernel (at last!); the overall performance
2930 penalty in practical applications is about 50%, while reliability of
2931 the Isabelle inference kernel has been greatly improved;
2933 * print modes "brackets" and "no_brackets" control output of nested =>
2934 (types) and ==> (props); the default behaviour is "brackets";
2936 * Provers: fast_tac (and friends) now handle actual object-logic rules
2937 as assumptions as well;
2939 * system: support Poly/ML 4.0;
2941 * system: isatool install handles KDE version 1 or 2;
2945 New in Isabelle99-1 (October 2000)
2946 ----------------------------------
2948 *** Overview of INCOMPATIBILITIES ***
2950 * HOL: simplification of natural numbers is much changed; to partly
2951 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
2952 issue the following ML commands:
2954 Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
2955 Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
2957 * HOL: simplification no longer dives into case-expressions; this is
2958 controlled by "t.weak_case_cong" for each datatype t;
2960 * HOL: nat_less_induct renamed to less_induct;
2962 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
2963 fixsome to patch .thy and .ML sources automatically;
2965 select_equality -> some_equality
2966 select_eq_Ex -> some_eq_ex
2967 selectI2EX -> someI2_ex
2968 selectI2 -> someI2
2969 selectI -> someI
2970 select1_equality -> some1_equality
2971 Eps_sym_eq -> some_sym_eq_trivial
2972 Eps_eq -> some_eq_trivial
2974 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
2976 * HOL: removed obsolete theorem binding expand_if (refer to split_if
2977 instead);
2979 * HOL: the recursion equations generated by 'recdef' are now called
2980 f.simps instead of f.rules;
2982 * HOL: qed_spec_mp now also handles bounded ALL as well;
2984 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
2985 sometimes be needed;
2987 * HOL: the constant for "f``x" is now "image" rather than "op ``";
2989 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
2991 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
2992 product is now "<*>" instead of "Times"; the lexicographic product is
2993 now "<*lex*>" instead of "**";
2995 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
2996 of main HOL, but was unused); better use HOL's datatype package;
2998 * HOL: removed "symbols" syntax for constant "override" of theory Map;
2999 the old syntax may be recovered as follows:
3001 syntax (symbols)
3002 override :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
3003 (infixl "\\<oplus>" 100)
3005 * HOL/Real: "rabs" replaced by overloaded "abs" function;
3007 * HOL/ML: even fewer consts are declared as global (see theories Ord,
3008 Lfp, Gfp, WF); this only affects ML packages that refer to const names
3009 internally;
3011 * HOL and ZF: syntax for quotienting wrt an equivalence relation
3012 changed from A/r to A//r;
3014 * ZF: new treatment of arithmetic (nat & int) may break some old
3015 proofs;
3017 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
3018 rulify -> rule_format, elimify -> elim_format, ...);
3020 * Isar/Provers: intro/elim/dest attributes changed; renamed
3021 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
3022 should have to change intro!! to intro? only); replaced "delrule" by
3023 "rule del";
3025 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
3027 * Provers: strengthened force_tac by using new first_best_tac;
3029 * LaTeX document preparation: several changes of isabelle.sty (see
3030 lib/texinputs);
3033 *** Document preparation ***
3035 * formal comments (text blocks etc.) in new-style theories may now
3036 contain antiquotations of thm/prop/term/typ/text to be presented
3037 according to latex print mode; concrete syntax is like this:
3038 @{term[show_types] "f(x) = a + x"};
3040 * isatool mkdir provides easy setup of Isabelle session directories,
3041 including proper document sources;
3043 * generated LaTeX sources are now deleted after successful run
3044 (isatool document -c); may retain a copy somewhere else via -D option
3045 of isatool usedir;
3047 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
3048 style files, achieving self-contained LaTeX sources and simplifying
3049 LaTeX debugging;
3051 * old-style theories now produce (crude) LaTeX output as well;
3053 * browser info session directories are now self-contained (may be put
3054 on WWW server seperately); improved graphs of nested sessions; removed
3055 graph for 'all sessions';
3057 * several improvements in isabelle style files; \isabellestyle{it}
3058 produces fake math mode output; \isamarkupheader is now \section by
3059 default; see lib/texinputs/isabelle.sty etc.;
3062 *** Isar ***
3064 * Isar/Pure: local results and corresponding term bindings are now
3065 subject to Hindley-Milner polymorphism (similar to ML); this
3066 accommodates incremental type-inference very nicely;
3068 * Isar/Pure: new derived language element 'obtain' supports
3069 generalized existence reasoning;
3071 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
3072 support accumulation of results, without applying any rules yet;
3073 useful to collect intermediate results without explicit name
3074 references, and for use with transitivity rules with more than 2
3075 premises;
3077 * Isar/Pure: scalable support for case-analysis type proofs: new
3078 'case' language element refers to local contexts symbolically, as
3079 produced by certain proof methods; internally, case names are attached
3080 to theorems as "tags";
3082 * Isar/Pure: theory command 'hide' removes declarations from
3083 class/type/const name spaces;
3085 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
3086 indicate potential overloading;
3088 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
3090 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
3091 "{a,b,c}" instead of {a,b,c};
3093 * Isar/Pure now provides its own version of intro/elim/dest
3094 attributes; useful for building new logics, but beware of confusion
3095 with the version in Provers/classical;
3097 * Isar/Pure: the local context of (non-atomic) goals is provided via
3098 case name 'antecedent';
3100 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
3101 to the current context is now done automatically);
3103 * Isar/Pure: theory command 'method_setup' provides a simple interface
3104 for definining proof methods in ML;
3106 * Isar/Provers: intro/elim/dest attributes changed; renamed
3107 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
3108 most cases, one should have to change intro!! to intro? only);
3109 replaced "delrule" by "rule del";
3111 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
3112 'symmetric' attribute (the latter supercedes [RS sym]);
3114 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
3115 method modifier); 'simp' method: 'only:' modifier removes loopers as
3116 well (including splits);
3118 * Isar/Provers: Simplifier and Classical methods now support all kind
3119 of modifiers used in the past, including 'cong', 'iff', etc.
3121 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
3122 of Simplifier and Classical reasoner);
3124 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
3125 now support named cases; major packages (inductive, datatype, primrec,
3126 recdef) support case names and properly name parameters;
3128 * Isar/HOL: new transitivity rules for substitution in inequalities --
3129 monotonicity conditions are extracted to be proven at end of
3130 calculations;
3132 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
3133 method anyway;
3135 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
3136 split_if split_if_asm; datatype package provides theorems foo.splits =
3137 foo.split foo.split_asm for each datatype;
3139 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
3140 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
3141 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
3142 use "(cases (simplified))" method in proper proof texts);
3144 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
3146 * Isar: names of theorems etc. may be natural numbers as well;
3148 * Isar: 'pr' command: optional arguments for goals_limit and
3149 ProofContext.prems_limit; no longer prints theory contexts, but only
3150 proof states;
3152 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
3153 additional print modes to be specified; e.g. "pr(latex)" will print
3154 proof state according to the Isabelle LaTeX style;
3156 * Isar: improved support for emulating tactic scripts, including proof
3157 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
3158 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
3159 (for HOL datatypes);
3161 * Isar: simplified (more robust) goal selection of proof methods: 1st
3162 goal, all goals, or explicit goal specifier (tactic emulation); thus
3163 'proof method scripts' have to be in depth-first order;
3165 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
3167 * Isar: removed 'help' command, which hasn't been too helpful anyway;
3168 should instead use individual commands for printing items
3169 (print_commands, print_methods etc.);
3171 * Isar: added 'nothing' --- the empty list of theorems;
3176 * HOL/MicroJava: formalization of a fragment of Java, together with a
3177 corresponding virtual machine and a specification of its bytecode
3178 verifier and a lightweight bytecode verifier, including proofs of
3179 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
3180 Cornelia Pusch (see also the homepage of project Bali at
3181 http://isabelle.in.tum.de/Bali/);
3183 * HOL/Algebra: new theory of rings and univariate polynomials, by
3184 Clemens Ballarin;
3186 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
3187 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
3188 Rasmussen;
3190 * HOL/Lattice: fundamental concepts of lattice theory and order
3191 structures, including duals, properties of bounds versus algebraic
3192 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
3193 Theorem for complete lattices etc.; may also serve as a demonstration
3194 for abstract algebraic reasoning using axiomatic type classes, and
3195 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
3197 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
3198 von Oheimb;
3200 * HOL/IMPP: extension of IMP with local variables and mutually
3201 recursive procedures, by David von Oheimb;
3203 * HOL/Lambda: converted into new-style theory and document;
3205 * HOL/ex/Multiquote: example of multiple nested quotations and
3206 anti-quotations -- basically a generalized version of de-Bruijn
3207 representation; very useful in avoiding lifting of operations;
3209 * HOL/record: added general record equality rule to simpset; fixed
3210 select-update simplification procedure to handle extended records as
3211 well; admit "r" as field name;
3213 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
3214 other numeric types and also as the identity of groups, rings, etc.;
3216 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
3217 Types nat and int belong to this axclass;
3219 * HOL: greatly improved simplification involving numerals of type nat, int, real:
3220 (i + #8 + j) = Suc k simplifies to #7 + (i + j) = k
3221 i*j + k + j*#3*i simplifies to #4*(i*j) + k
3222 two terms #m*u and #n*u are replaced by #(m+n)*u
3223 (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
3224 and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
3225 or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
3227 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
3228 powerful prover for predicate logic but knows nothing of clasets; see
3229 ex/mesontest.ML and ex/mesontest2.ML for example applications;
3231 * HOL: new version of "case_tac" subsumes both boolean case split and
3232 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
3233 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
3235 * HOL: simplification no longer dives into case-expressions: only the
3236 selector expression is simplified, but not the remaining arms; to
3237 enable full simplification of case-expressions for datatype t, you may
3238 remove t.weak_case_cong from the simpset, either globally (Delcongs
3239 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
3241 * HOL/recdef: the recursion equations generated by 'recdef' for
3242 function 'f' are now called f.simps instead of f.rules; if all
3243 termination conditions are proved automatically, these simplification
3244 rules are added to the simpset, as in primrec; rules may be named
3245 individually as well, resulting in a separate list of theorems for
3246 each equation;
3248 * HOL/While is a new theory that provides a while-combinator. It
3249 permits the definition of tail-recursive functions without the
3250 provision of a termination measure. The latter is necessary once the
3251 invariant proof rule for while is applied.
3253 * HOL: new (overloaded) notation for the set of elements below/above
3254 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
3256 * HOL: theorems impI, allI, ballI bound as "strip";
3258 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
3259 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
3260 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
3262 * HOL/Real: "rabs" replaced by overloaded "abs" function;
3264 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
3265 main HOL, but was unused);
3267 * HOL: fewer consts declared as global (e.g. have to refer to
3268 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
3270 * HOL: tuned AST representation of nested pairs, avoiding bogus output
3271 in case of overlap with user translations (e.g. judgements over
3272 tuples); (note that the underlying logical represenation is still
3273 bogus);
3278 * ZF: simplification automatically cancels common terms in arithmetic
3279 expressions over nat and int;
3281 * ZF: new treatment of nat to minimize type-checking: all operators
3282 coerce their operands to a natural number using the function natify,
3283 making the algebraic laws unconditional;
3285 * ZF: as above, for int: operators coerce their operands to an integer
3286 using the function intify;
3288 * ZF: the integer library now contains many of the usual laws for the
3289 orderings, including $<=, and monotonicity laws for $+ and $*;
3291 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
3292 simplification;
3294 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
3295 to the simplifier and classical reasoner simultaneously;
3298 *** General ***
3300 * Provers: blast_tac now handles actual object-logic rules as
3301 assumptions; note that auto_tac uses blast_tac internally as well;
3303 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
3304 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
3306 * Provers: delrules now handles destruct rules as well (no longer need
3307 explicit make_elim);
3309 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
3310 [| inj ?f; ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
3311 use instead the strong form,
3312 [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
3313 in HOL, FOL and ZF the function cla_make_elim will create such rules
3314 from destruct-rules;
3316 * Provers: Simplifier.easy_setup provides a fast path to basic
3317 Simplifier setup for new object-logics;
3319 * Pure: AST translation rules no longer require constant head on LHS;
3321 * Pure: improved name spaces: ambiguous output is qualified; support
3322 for hiding of names;
3324 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
3325 XSYMBOL_HOME; no longer need to do manual configuration in most
3326 situations;
3328 * system: compression of ML heaps images may now be controlled via -c
3329 option of isabelle and isatool usedir (currently only observed by
3330 Poly/ML);
3332 * system: isatool installfonts may handle X-Symbol fonts as well (very
3333 useful for remote X11);
3335 * system: provide TAGS file for Isabelle sources;
3337 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
3338 order;
3340 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
3341 timing flag supersedes proof_timing and Toplevel.trace;
3343 * ML: new combinators |>> and |>>> for incremental transformations
3344 with secondary results (e.g. certain theory extensions):
3346 * ML: PureThy.add_defs gets additional argument to indicate potential
3347 overloading (usually false);
3349 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
3350 results;
3354 New in Isabelle99 (October 1999)
3355 --------------------------------
3357 *** Overview of INCOMPATIBILITIES (see below for more details) ***
3359 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
3360 are no longer simplified. (This allows the simplifier to unfold recursive
3361 functional programs.) To restore the old behaviour, declare
3363 Delcongs [if_weak_cong];
3365 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
3366 complement;
3368 * HOL: the predicate "inj" is now defined by translation to "inj_on";
3370 * HOL/datatype: mutual_induct_tac no longer exists --
3371 use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
3373 * HOL/typedef: fixed type inference for representing set; type
3374 arguments now have to occur explicitly on the rhs as type constraints;
3376 * ZF: The con_defs part of an inductive definition may no longer refer
3377 to constants declared in the same theory;
3379 * HOL, ZF: the function mk_cases, generated by the inductive
3380 definition package, has lost an argument. To simplify its result, it
3381 uses the default simpset instead of a supplied list of theorems.
3383 * HOL/List: the constructors of type list are now Nil and Cons;
3385 * Simplifier: the type of the infix ML functions
3386 setSSolver addSSolver setSolver addSolver
3387 is now simpset * solver -> simpset where `solver' is a new abstract type
3388 for packaging solvers. A solver is created via
3389 mk_solver: string -> (thm list -> int -> tactic) -> solver
3390 where the string argument is only a comment.
3393 *** Proof tools ***
3395 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
3396 decision procedure for linear arithmetic. Currently it is used for
3397 types `nat', `int', and `real' in HOL (see below); it can, should and
3398 will be instantiated for other types and logics as well.
3400 * The simplifier now accepts rewrite rules with flexible heads, eg
3401 hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
3402 They are applied like any rule with a non-pattern lhs, i.e. by first-order
3403 matching.
3406 *** General ***
3408 * New Isabelle/Isar subsystem provides an alternative to traditional
3409 tactical theorem proving; together with the ProofGeneral/isar user
3410 interface it offers an interactive environment for developing human
3411 readable proof documents (Isar == Intelligible semi-automated
3412 reasoning); for further information see isatool doc isar-ref,
3413 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
3415 * improved and simplified presentation of theories: better HTML markup
3416 (including colors), graph views in several sizes; isatool usedir now
3417 provides a proper interface for user theories (via -P option); actual
3418 document preparation based on (PDF)LaTeX is available as well (for
3419 new-style theories only); see isatool doc system for more information;
3421 * native support for Proof General, both for classic Isabelle and
3422 Isabelle/Isar;
3424 * ML function thm_deps visualizes dependencies of theorems and lemmas,
3425 using the graph browser tool;
3427 * Isabelle manuals now also available as PDF;
3429 * theory loader rewritten from scratch (may not be fully
3430 bug-compatible); old loadpath variable has been replaced by show_path,
3431 add_path, del_path, reset_path functions; new operations such as
3432 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
3433 isatool doc ref);
3435 * improved isatool install: option -k creates KDE application icon,
3436 option -p DIR installs standalone binaries;
3438 * added ML_PLATFORM setting (useful for cross-platform installations);
3439 more robust handling of platform specific ML images for SML/NJ;
3441 * the settings environment is now statically scoped, i.e. it is never
3442 created again in sub-processes invoked from isabelle, isatool, or
3443 Isabelle;
3445 * path element specification '~~' refers to '$ISABELLE_HOME';
3447 * in locales, the "assumes" and "defines" parts may be omitted if
3448 empty;
3450 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
3451 long arrows);
3453 * new print_mode "HTML";
3455 * new flag show_tags controls display of tags of theorems (which are
3456 basically just comments that may be attached by some tools);
3458 * Isamode 2.6 requires patch to accomodate change of Isabelle font
3459 mode and goal output format:
3461 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
3462 244c244
3463 < (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
3464 ---
3465 > (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
3466 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
3467 181c181
3468 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
3469 ---
3470 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
3472 * function bind_thms stores lists of theorems (cf. bind_thm);
3474 * new shorthand tactics ftac, eatac, datac, fatac;
3476 * qed (and friends) now accept "" as result name; in that case the
3477 theorem is not stored, but proper checks and presentation of the
3478 result still apply;
3480 * theorem database now also indexes constants "Trueprop", "all",
3481 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
3486 ** HOL arithmetic **
3488 * There are now decision procedures for linear arithmetic over nat and
3489 int:
3491 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
3492 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
3493 are treated as atomic; subformulae not involving type `nat' or `int'
3494 are ignored; quantified subformulae are ignored unless they are
3495 positive universal or negative existential. The tactic has to be
3496 invoked by hand and can be a little bit slow. In particular, the
3497 running time is exponential in the number of occurrences of `min' and
3498 `max', and `-' on `nat'.
3500 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
3501 (negated) (in)equalities among the premises and the conclusion into
3502 account (i.e. no compound formulae) and does not know about `min' and
3503 `max', and `-' on `nat'. It is fast and is used automatically by the
3504 simplifier.
3506 NB: At the moment, these decision procedures do not cope with mixed
3507 nat/int formulae where the two parts interact, such as `m < n ==>
3508 int(m) < int(n)'.
3510 * HOL/Numeral provides a generic theory of numerals (encoded
3511 efficiently as bit strings); setup for types nat/int/real is in place;
3512 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
3513 int, existing theories and proof scripts may require a few additional
3514 type constraints;
3516 * integer division and remainder can now be performed on constant
3517 arguments;
3519 * many properties of integer multiplication, division and remainder
3520 are now available;
3522 * An interface to the Stanford Validity Checker (SVC) is available through the
3523 tactic svc_tac. Propositional tautologies and theorems of linear arithmetic
3524 are proved automatically. SVC must be installed separately, and its results
3525 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
3526 invocation of the underlying oracle). For SVC see
3527 http://verify.stanford.edu/SVC
3529 * IsaMakefile: the HOL-Real target now builds an actual image;
3532 ** HOL misc **
3534 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
3535 (in Isabelle/Isar) -- by Gertrud Bauer;
3537 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
3538 analysis for assembly languages with subtypes;
3540 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
3541 -- avoids syntactic ambiguities and treats state, transition, and
3542 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
3543 changed syntax and (many) tactics;
3545 * HOL/inductive: Now also handles more general introduction rules such
3546 as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
3547 theorems are now maintained within the theory (maintained via the
3548 "mono" attribute);
3550 * HOL/datatype: Now also handles arbitrarily branching datatypes
3551 (using function types) such as
3553 datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
3555 * HOL/record: record_simproc (part of the default simpset) takes care
3556 of selectors applied to updated records; record_split_tac is no longer
3557 part of the default claset; update_defs may now be removed from the
3558 simpset in many cases; COMPATIBILITY: old behavior achieved by
3560 claset_ref () := claset() addSWrapper record_split_wrapper;
3561 Delsimprocs [record_simproc]
3563 * HOL/typedef: fixed type inference for representing set; type
3564 arguments now have to occur explicitly on the rhs as type constraints;
3566 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
3567 names rather than an ML expression;
3569 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
3570 supplied later. Program schemes can be defined, such as
3571 "While B C s = (if B s then While B C (C s) else s)"
3572 where the well-founded relation can be chosen after B and C have been given.
3574 * HOL/List: the constructors of type list are now Nil and Cons;
3575 INCOMPATIBILITY: while [] and infix # syntax is still there, of
3576 course, ML tools referring to List.list.op # etc. have to be adapted;
3578 * HOL_quantifiers flag superseded by "HOL" print mode, which is
3579 disabled by default; run isabelle with option -m HOL to get back to
3580 the original Gordon/HOL-style output;
3582 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
3583 ALL x<=y. P, EX x<y. P, EX x<=y. P;
3585 * HOL basic syntax simplified (more orthogonal): all variants of
3586 All/Ex now support plain / symbolic / HOL notation; plain syntax for
3587 Eps operator is provided as well: "SOME x. P[x]";
3589 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
3591 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
3592 thus available for user theories;
3594 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
3595 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
3596 time;
3598 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
3599 several times and then mp;
3604 * the notation <<...>> is now available as a notation for sequences of
3605 formulas;
3607 * the simplifier is now installed
3609 * the axiom system has been generalized (thanks to Soren Heilmann)
3611 * the classical reasoner now has a default rule database
3616 * new primrec section allows primitive recursive functions to be given
3617 directly (as in HOL) over datatypes and the natural numbers;
3619 * new tactics induct_tac and exhaust_tac for induction (or case
3620 analysis) over datatypes and the natural numbers;
3622 * the datatype declaration of type T now defines the recursor T_rec;
3624 * simplification automatically does freeness reasoning for datatype
3625 constructors;
3627 * automatic type-inference, with AddTCs command to insert new
3628 type-checking rules;
3630 * datatype introduction rules are now added as Safe Introduction rules
3631 to the claset;
3633 * the syntax "if P then x else y" is now available in addition to
3634 if(P,x,y);
3637 *** Internal programming interfaces ***
3639 * tuned simplifier trace output; new flag debug_simp;
3641 * structures Vartab / Termtab (instances of TableFun) offer efficient
3642 tables indexed by indexname_ord / term_ord (compatible with aconv);
3644 * AxClass.axclass_tac lost the theory argument;
3646 * tuned current_goals_markers semantics: begin / end goal avoids
3647 printing empty lines;
3649 * removed prs and prs_fn hook, which was broken because it did not
3650 include \n in its semantics, forcing writeln to add one
3651 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
3652 string -> unit if you really want to output text without newline;
3654 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
3655 plain output, interface builders may have to enable 'isabelle_font'
3656 mode to get Isabelle font glyphs as before;
3658 * refined token_translation interface; INCOMPATIBILITY: output length
3659 now of type real instead of int;
3661 * theory loader actions may be traced via new ThyInfo.add_hook
3662 interface (see src/Pure/Thy/thy_info.ML); example application: keep
3663 your own database of information attached to *whole* theories -- as
3664 opposed to intra-theory data slots offered via TheoryDataFun;
3666 * proper handling of dangling sort hypotheses (at last!);
3667 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
3668 extra sort hypotheses that can be witnessed from the type signature;
3669 the force_strip_shyps flag is gone, any remaining shyps are simply
3670 left in the theorem (with a warning issued by strip_shyps_warning);
3674 New in Isabelle98-1 (October 1998)
3675 ----------------------------------
3677 *** Overview of INCOMPATIBILITIES (see below for more details) ***
3679 * several changes of automated proof tools;
3681 * HOL: major changes to the inductive and datatype packages, including
3682 some minor incompatibilities of theory syntax;
3684 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
3685 called `inj_on';
3687 * HOL: removed duplicate thms in Arith:
3688 less_imp_add_less should be replaced by trans_less_add1
3689 le_imp_add_le should be replaced by trans_le_add1
3691 * HOL: unary minus is now overloaded (new type constraints may be
3692 required);
3694 * HOL and ZF: unary minus for integers is now #- instead of #~. In
3695 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
3696 now taken as an integer constant.
3698 * Pure: ML function 'theory_of' renamed to 'theory';
3701 *** Proof tools ***
3703 * Simplifier:
3704 1. Asm_full_simp_tac is now more aggressive.
3705 1. It will sometimes reorient premises if that increases their power to
3706 simplify.
3707 2. It does no longer proceed strictly from left to right but may also
3708 rotate premises to achieve further simplification.
3709 For compatibility reasons there is now Asm_lr_simp_tac which is like the
3710 old Asm_full_simp_tac in that it does not rotate premises.
3711 2. The simplifier now knows a little bit about nat-arithmetic.
3713 * Classical reasoner: wrapper mechanism for the classical reasoner now
3714 allows for selected deletion of wrappers, by introduction of names for
3715 wrapper functionals. This implies that addbefore, addSbefore,
3716 addaltern, and addSaltern now take a pair (name, tactic) as argument,
3717 and that adding two tactics with the same name overwrites the first
3718 one (emitting a warning).
3719 type wrapper = (int -> tactic) -> (int -> tactic)
3720 setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
3721 addWrapper, addSWrapper: claset * (string * wrapper) -> claset
3722 delWrapper, delSWrapper: claset * string -> claset
3723 getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
3725 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
3726 semantics; addbefore now affects only the unsafe part of step_tac
3727 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
3728 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
3729 by Force_tac;
3731 * Classical reasoner: setwrapper to setWrapper and compwrapper to
3732 compWrapper; added safe wrapper (and access functions for it);
3734 * HOL/split_all_tac is now much faster and fails if there is nothing
3735 to split. Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
3736 and the names of the automatically generated variables have changed.
3737 split_all_tac has moved within claset() from unsafe wrappers to safe
3738 wrappers, which means that !!-bound variables are split much more
3739 aggressively, and safe_tac and clarify_tac now split such variables.
3740 If this splitting is not appropriate, use delSWrapper "split_all_tac".
3741 Note: the same holds for record_split_tac, which does the job of
3742 split_all_tac for record fields.
3744 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
3745 permanently to the default simpset using Addsplits just like
3746 Addsimps. They can be removed via Delsplits just like
3747 Delsimps. Lower-case versions are also available.
3749 * HOL/Simplifier: The rule split_if is now part of the default
3750 simpset. This means that the simplifier will eliminate all occurrences
3751 of if-then-else in the conclusion of a goal. To prevent this, you can
3752 either remove split_if completely from the default simpset by
3753 `Delsplits [split_if]' or remove it in a specific call of the
3754 simplifier using `... delsplits [split_if]'. You can also add/delete
3755 other case splitting rules to/from the default simpset: every datatype
3756 generates suitable rules `split_t_case' and `split_t_case_asm' (where
3757 t is the name of the datatype).
3759 * Classical reasoner / Simplifier combination: new force_tac (and
3760 derivatives Force_tac, force) combines rewriting and classical
3761 reasoning (and whatever other tools) similarly to auto_tac, but is
3762 aimed to solve the given subgoal completely.
3765 *** General ***
3767 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
3768 and `goalw': the theory is no longer needed as an explicit argument -
3769 the current theory context is used; assumptions are no longer returned
3770 at the ML-level unless one of them starts with ==> or !!; it is
3771 recommended to convert to these new commands using isatool fixgoal
3772 (backup your sources first!);
3774 * new top-level commands 'thm' and 'thms' for retrieving theorems from
3775 the current theory context, and 'theory' to lookup stored theories;
3777 * new theory section 'locale' for declaring constants, assumptions and
3778 definitions that have local scope;
3780 * new theory section 'nonterminals' for purely syntactic types;
3782 * new theory section 'setup' for generic ML setup functions
3783 (e.g. package initialization);
3785 * the distribution now includes Isabelle icons: see
3786 lib/logo/isabelle-{small,tiny}.xpm;
3788 * isatool install - install binaries with absolute references to
3789 ISABELLE_HOME/bin;
3791 * isatool logo -- create instances of the Isabelle logo (as EPS);
3793 * print mode 'emacs' reserved for Isamode;
3795 * support multiple print (ast) translations per constant name;
3797 * theorems involving oracles are now printed with a suffixed [!];
3802 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
3804 * HOL/inductive package reorganized and improved: now supports mutual
3805 definitions such as
3807 inductive EVEN ODD
3808 intrs
3809 null "0 : EVEN"
3810 oddI "n : EVEN ==> Suc n : ODD"
3811 evenI "n : ODD ==> Suc n : EVEN"
3813 new theorem list "elims" contains an elimination rule for each of the
3814 recursive sets; inductive definitions now handle disjunctive premises
3815 correctly (also ZF);
3817 INCOMPATIBILITIES: requires Inductive as an ancestor; component
3818 "mutual_induct" no longer exists - the induction rule is always
3819 contained in "induct";
3822 * HOL/datatype package re-implemented and greatly improved: now
3823 supports mutually recursive datatypes such as
3825 datatype
3826 'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
3827 | SUM ('a aexp) ('a aexp)
3828 | DIFF ('a aexp) ('a aexp)
3829 | NUM 'a
3830 and
3831 'a bexp = LESS ('a aexp) ('a aexp)
3832 | AND ('a bexp) ('a bexp)
3833 | OR ('a bexp) ('a bexp)
3835 as well as indirectly recursive datatypes such as
3837 datatype
3838 ('a, 'b) term = Var 'a
3839 | App 'b ((('a, 'b) term) list)
3841 The new tactic mutual_induct_tac [<var_1>, ..., <var_n>] i performs
3842 induction on mutually / indirectly recursive datatypes.
3844 Primrec equations are now stored in theory and can be accessed via
3845 <function_name>.simps.
3849 - Theories using datatypes must now have theory Datatype as an
3850 ancestor.
3851 - The specific <typename>.induct_tac no longer exists - use the
3852 generic induct_tac instead.
3853 - natE has been renamed to nat.exhaust - use exhaust_tac
3854 instead of res_inst_tac ... natE. Note that the variable
3855 names in nat.exhaust differ from the names in natE, this
3856 may cause some "fragile" proofs to fail.
3857 - The theorems split_<typename>_case and split_<typename>_case_asm
3858 have been renamed to <typename>.split and <typename>.split_asm.
3859 - Since default sorts of type variables are now handled correctly,
3860 some datatype definitions may have to be annotated with explicit
3861 sort constraints.
3862 - Primrec definitions no longer require function name and type
3863 of recursive argument.
3865 Consider using isatool fixdatatype to adapt your theories and proof
3866 scripts to the new package (backup your sources first!).
3869 * HOL/record package: considerably improved implementation; now
3870 includes concrete syntax for record types, terms, updates; theorems
3871 for surjective pairing and splitting !!-bound record variables; proof
3872 support is as follows:
3874 1) standard conversions (selectors or updates applied to record
3875 constructor terms) are part of the standard simpset;
3877 2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
3878 made part of standard simpset and claset via addIffs;
3880 3) a tactic for record field splitting (record_split_tac) is part of
3881 the standard claset (addSWrapper);
3883 To get a better idea about these rules you may retrieve them via
3884 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
3885 the name of your record type.
3887 The split tactic 3) conceptually simplifies by the following rule:
3889 "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
3891 Thus any record variable that is bound by meta-all will automatically
3892 blow up into some record constructor term, consequently the
3893 simplifications of 1), 2) apply. Thus force_tac, auto_tac etc. shall
3894 solve record problems automatically.
3897 * reorganized the main HOL image: HOL/Integ and String loaded by
3898 default; theory Main includes everything;
3900 * automatic simplification of integer sums and comparisons, using cancellation;
3902 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
3904 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
3906 * many new identities for unions, intersections, set difference, etc.;
3908 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
3909 called split_if, split_split, split_sum_case and split_nat_case (to go
3910 with add/delsplits);
3912 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
3913 (?x::unit) = (); this is made part of the default simpset, which COULD
3914 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
3915 'Delsimprocs [unit_eq_proc];' as last resort); also note that
3916 unit_abs_eta_conv is added in order to counter the effect of
3917 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
3918 %u.f();
3920 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
3921 makes more sense);
3923 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
3924 It and 'sym RS equals0D' are now in the default claset, giving automatic
3925 disjointness reasoning but breaking a few old proofs.
3927 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
3928 to 'converse' from 'inverse' (for compatibility with ZF and some
3929 literature);
3931 * HOL/recdef can now declare non-recursive functions, with {} supplied as
3932 the well-founded relation;
3934 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
3935 Compl A. The "Compl" syntax remains available as input syntax for this
3936 release ONLY.
3938 * HOL/Update: new theory of function updates:
3939 f(a:=b) == %x. if x=a then b else f x
3940 may also be iterated as in f(a:=b,c:=d,...);
3942 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
3944 * HOL/List:
3945 - new function list_update written xs[i:=v] that updates the i-th
3946 list position. May also be iterated as in xs[i:=a,j:=b,...].
3947 - new function `upt' written [i..j(] which generates the list
3948 [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
3949 bound write [i..j], which is a shorthand for [i..j+1(].
3950 - new lexicographic orderings and corresponding wellfoundedness theorems.
3952 * HOL/Arith:
3953 - removed 'pred' (predecessor) function;
3954 - generalized some theorems about n-1;
3955 - many new laws about "div" and "mod";
3956 - new laws about greatest common divisors (see theory ex/Primes);
3958 * HOL/Relation: renamed the relational operator r^-1 "converse"
3959 instead of "inverse";
3961 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
3962 of the multiset ordering;
3964 * directory HOL/Real: a construction of the reals using Dedekind cuts
3965 (not included by default);
3967 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
3969 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
3970 programs, i.e. different program variables may have different types.
3972 * calling (stac rew i) now fails if "rew" has no effect on the goal
3973 [previously, this check worked only if the rewrite rule was unconditional]
3974 Now rew can involve either definitions or equalities (either == or =).
3979 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
3980 only the theorems proved on ZF.ML;
3982 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
3983 It and 'sym RS equals0D' are now in the default claset, giving automatic
3984 disjointness reasoning but breaking a few old proofs.
3986 * ZF/Update: new theory of function updates
3987 with default rewrite rule f(x:=y) ` z = if(z=x, y, f`z)
3988 may also be iterated as in f(a:=b,c:=d,...);
3990 * in let x=t in u(x), neither t nor u(x) has to be an FOL term.
3992 * calling (stac rew i) now fails if "rew" has no effect on the goal
3993 [previously, this check worked only if the rewrite rule was unconditional]
3994 Now rew can involve either definitions or equalities (either == or =).
3996 * case_tac provided for compatibility with HOL
3997 (like the old excluded_middle_tac, but with subgoals swapped)
4000 *** Internal programming interfaces ***
4002 * Pure: several new basic modules made available for general use, see
4003 also src/Pure/README;
4005 * improved the theory data mechanism to support encapsulation (data
4006 kind name replaced by private Object.kind, acting as authorization
4007 key); new type-safe user interface via functor TheoryDataFun; generic
4008 print_data function becomes basically useless;
4010 * removed global_names compatibility flag -- all theory declarations
4011 are qualified by default;
4013 * module Pure/Syntax now offers quote / antiquote translation
4014 functions (useful for Hoare logic etc. with implicit dependencies);
4015 see HOL/ex/Antiquote for an example use;
4017 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
4018 cterm -> thm;
4020 * new tactical CHANGED_GOAL for checking that a tactic modifies a
4021 subgoal;
4023 * Display.print_goals function moved to Locale.print_goals;
4025 * standard print function for goals supports current_goals_markers
4026 variable for marking begin of proof, end of proof, start of goal; the
4027 default is ("", "", ""); setting current_goals_markers := ("<proof>",
4028 "</proof>", "<goal>") causes SGML like tagged proof state printing,
4029 for example;
4033 New in Isabelle98 (January 1998)
4034 --------------------------------
4036 *** Overview of INCOMPATIBILITIES (see below for more details) ***
4038 * changed lexical syntax of terms / types: dots made part of long
4039 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
4041 * simpset (and claset) reference variable replaced by functions
4042 simpset / simpset_ref;
4044 * no longer supports theory aliases (via merge) and non-trivial
4045 implicit merge of thms' signatures;
4047 * most internal names of constants changed due to qualified names;
4049 * changed Pure/Sequence interface (see Pure/seq.ML);
4052 *** General Changes ***
4054 * hierachically structured name spaces (for consts, types, axms, thms
4055 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
4056 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
4057 isatool fixdots ensures space after dots (e.g. "%x. x"); set
4058 long_names for fully qualified output names; NOTE: ML programs
4059 (special tactics, packages etc.) referring to internal names may have
4060 to be adapted to cope with fully qualified names; in case of severe
4061 backward campatibility problems try setting 'global_names' at compile
4062 time to have enrything declared within a flat name space; one may also
4063 fine tune name declarations in theories via the 'global' and 'local'
4064 section;
4066 * reimplemented the implicit simpset and claset using the new anytype
4067 data filed in signatures; references simpset:simpset ref etc. are
4068 replaced by functions simpset:unit->simpset and
4069 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
4070 to patch your ML files accordingly;
4072 * HTML output now includes theory graph data for display with Java
4073 applet or isatool browser; data generated automatically via isatool
4074 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
4076 * defs may now be conditional; improved rewrite_goals_tac to handle
4077 conditional equations;
4079 * defs now admits additional type arguments, using TYPE('a) syntax;
4081 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
4082 creates a new theory node; implicit merge of thms' signatures is
4083 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
4084 transfer:theory->thm->thm in (rare) cases;
4086 * improved handling of draft signatures / theories; draft thms (and
4087 ctyps, cterms) are automatically promoted to real ones;
4089 * slightly changed interfaces for oracles: admit many per theory, named
4090 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
4092 * print_goals: optional output of const types (set show_consts and
4093 show_types);
4095 * improved output of warnings (###) and errors (***);
4097 * subgoal_tac displays a warning if the new subgoal has type variables;
4099 * removed old README and Makefiles;
4101 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
4103 * removed obsolete init_pps and init_database;
4105 * deleted the obsolete tactical STATE, which was declared by
4106 fun STATE tacfun st = tacfun st st;
4108 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
4109 (which abbreviates $HOME);
4111 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
4112 use isatool fixseq to adapt your ML programs (this works for fully
4113 qualified references to the Sequence structure only!);
4115 * use_thy no longer requires writable current directory; it always
4116 reloads .ML *and* .thy file, if either one is out of date;
4119 *** Classical Reasoner ***
4121 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
4122 tactics that use classical reasoning to simplify a subgoal without
4123 splitting it into several subgoals;
4125 * Safe_tac: like safe_tac but uses the default claset;
4128 *** Simplifier ***
4130 * added simplification meta rules:
4131 (asm_)(full_)simplify: simpset -> thm -> thm;
4133 * simplifier.ML no longer part of Pure -- has to be loaded by object
4134 logics (again);
4136 * added prems argument to simplification procedures;
4138 * HOL, FOL, ZF: added infix function `addsplits':
4139 instead of `<simpset> setloop (split_tac <thms>)'
4140 you can simply write `<simpset> addsplits <thms>'
4143 *** Syntax ***
4145 * TYPE('a) syntax for type reflection terms;
4147 * no longer handles consts with name "" -- declare as 'syntax' instead;
4149 * pretty printer: changed order of mixfix annotation preference (again!);
4151 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
4156 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
4157 with `addloop' of the simplifier to faciliate case splitting in premises.
4159 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
4161 * HOL/Auth: new protocol proofs including some for the Internet
4162 protocol TLS;
4164 * HOL/Map: new theory of `maps' a la VDM;
4166 * HOL/simplifier: simplification procedures nat_cancel_sums for
4167 cancelling out common nat summands from =, <, <= (in)equalities, or
4168 differences; simplification procedures nat_cancel_factor for
4169 cancelling common factor from =, <, <= (in)equalities over natural
4170 sums; nat_cancel contains both kinds of procedures, it is installed by
4171 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
4173 * HOL/simplifier: terms of the form
4174 `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)' (or t=x)
4175 are rewritten to
4176 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
4177 and those of the form
4178 `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)' (or t=x)
4179 are rewritten to
4180 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
4182 * HOL/datatype
4183 Each datatype `t' now comes with a theorem `split_t_case' of the form
4185 P(t_case f1 ... fn x) =
4186 ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
4187 ...
4188 (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
4189 )
4191 and a theorem `split_t_case_asm' of the form
4193 P(t_case f1 ... fn x) =
4194 ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
4195 ...
4196 (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
4197 )
4198 which can be added to a simpset via `addsplits'. The existing theorems
4199 expand_list_case and expand_option_case have been renamed to
4200 split_list_case and split_option_case.
4202 * HOL/Arithmetic:
4203 - `pred n' is automatically converted to `n-1'.
4204 Users are strongly encouraged not to use `pred' any longer,
4205 because it will disappear altogether at some point.
4206 - Users are strongly encouraged to write "0 < n" rather than
4207 "n ~= 0". Theorems and proof tools have been modified towards this
4208 `standard'.
4210 * HOL/Lists:
4211 the function "set_of_list" has been renamed "set" (and its theorems too);
4212 the function "nth" now takes its arguments in the reverse order and
4213 has acquired the infix notation "!" as in "xs!n".
4215 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
4217 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
4218 specialist theorems (like UN1_I) are gone. Similarly for (INT x.B x);
4220 * HOL/record: extensible records with schematic structural subtyping
4221 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
4222 still lacks various theorems and concrete record syntax;
4227 * removed "axioms" and "generated by" sections;
4229 * replaced "ops" section by extended "consts" section, which is capable of
4230 handling the continuous function space "->" directly;
4232 * domain package:
4233 . proves theorems immediately and stores them in the theory,
4234 . creates hierachical name space,
4235 . now uses normal mixfix annotations (instead of cinfix...),
4236 . minor changes to some names and values (for consistency),
4237 . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
4238 . separator between mutual domain defs: changed "," to "and",
4239 . improved handling of sort constraints; now they have to
4240 appear on the left-hand side of the equations only;
4242 * fixed LAM <x,y,zs>.b syntax;
4244 * added extended adm_tac to simplifier in HOLCF -- can now discharge
4245 adm (%x. P (t x)), where P is chainfinite and t continuous;
4248 *** FOL and ZF ***
4250 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
4251 with `addloop' of the simplifier to faciliate case splitting in premises.
4253 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
4254 in HOL, they strip ALL and --> from proved theorems;
4258 New in Isabelle94-8 (May 1997)
4259 ------------------------------
4261 *** General Changes ***
4263 * new utilities to build / run / maintain Isabelle etc. (in parts
4264 still somewhat experimental); old Makefiles etc. still functional;
4266 * new 'Isabelle System Manual';
4268 * INSTALL text, together with ./configure and ./build scripts;
4270 * reimplemented type inference for greater efficiency, better error
4271 messages and clean internal interface;
4273 * prlim command for dealing with lots of subgoals (an easier way of
4274 setting goals_limit);
4277 *** Syntax ***
4279 * supports alternative (named) syntax tables (parser and pretty
4280 printer); internal interface is provided by add_modesyntax(_i);
4282 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
4283 be used in conjunction with the Isabelle symbol font; uses the
4284 "symbols" syntax table;
4286 * added token_translation interface (may translate name tokens in
4287 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
4288 the current print_mode); IMPORTANT: user print translation functions
4289 are responsible for marking newly introduced bounds
4290 (Syntax.mark_boundT);
4292 * token translations for modes "xterm" and "xterm_color" that display
4293 names in bold, underline etc. or colors (which requires a color
4294 version of xterm);
4296 * infixes may now be declared with names independent of their syntax;
4298 * added typed_print_translation (like print_translation, but may
4299 access type of constant);
4302 *** Classical Reasoner ***
4304 Blast_tac: a new tactic! It is often more powerful than fast_tac, but has
4305 some limitations. Blast_tac...
4306 + ignores addss, addbefore, addafter; this restriction is intrinsic
4307 + ignores elimination rules that don't have the correct format
4308 (the conclusion MUST be a formula variable)
4309 + ignores types, which can make HOL proofs fail
4310 + rules must not require higher-order unification, e.g. apply_type in ZF
4311 [message "Function Var's argument not a bound variable" relates to this]
4312 + its proof strategy is more general but can actually be slower
4314 * substitution with equality assumptions no longer permutes other
4315 assumptions;
4317 * minor changes in semantics of addafter (now called addaltern); renamed
4318 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
4319 (and access functions for it);
4321 * improved combination of classical reasoner and simplifier:
4322 + functions for handling clasimpsets
4323 + improvement of addss: now the simplifier is called _after_ the
4324 safe steps.
4325 + safe variant of addss called addSss: uses safe simplifications
4326 _during_ the safe steps. It is more complete as it allows multiple
4327 instantiations of unknowns (e.g. with slow_tac).
4329 *** Simplifier ***
4331 * added interface for simplification procedures (functions that
4332 produce *proven* rewrite rules on the fly, depending on current
4333 redex);
4335 * ordering on terms as parameter (used for ordered rewriting);
4337 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
4339 * the solver is now split into a safe and an unsafe part.
4340 This should be invisible for the normal user, except that the
4341 functions setsolver and addsolver have been renamed to setSolver and
4342 addSolver; added safe_asm_full_simp_tac;
4347 * a generic induction tactic `induct_tac' which works for all datatypes and
4348 also for type `nat';
4350 * a generic case distinction tactic `exhaust_tac' which works for all
4351 datatypes and also for type `nat';
4353 * each datatype comes with a function `size';
4355 * patterns in case expressions allow tuple patterns as arguments to
4356 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
4358 * primrec now also works with type nat;
4360 * recdef: a new declaration form, allows general recursive functions to be
4361 defined in theory files. See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
4363 * the constant for negation has been renamed from "not" to "Not" to
4364 harmonize with FOL, ZF, LK, etc.;
4366 * HOL/ex/LFilter theory of a corecursive "filter" functional for
4367 infinite lists;
4369 * HOL/Modelcheck demonstrates invocation of model checker oracle;
4371 * HOL/ex/Ring.thy declares cring_simp, which solves equational
4372 problems in commutative rings, using axiomatic type classes for + and *;
4374 * more examples in HOL/MiniML and HOL/Auth;
4376 * more default rewrite rules for quantifiers, union/intersection;
4378 * a new constant `arbitrary == @x.False';
4380 * HOLCF/IOA replaces old HOL/IOA;
4382 * HOLCF changes: derived all rules and arities
4383 + axiomatic type classes instead of classes
4384 + typedef instead of faking type definitions
4385 + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
4386 + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
4387 + eliminated the types void, one, tr
4388 + use unit lift and bool lift (with translations) instead of one and tr
4389 + eliminated blift from Lift3.thy (use Def instead of blift)
4390 all eliminated rules are derived as theorems --> no visible changes ;
4395 * ZF now has Fast_tac, Simp_tac and Auto_tac. Union_iff is a now a default
4396 rewrite rule; this may affect some proofs. eq_cs is gone but can be put back
4397 as ZF_cs addSIs [equalityI];
4401 New in Isabelle94-7 (November 96)
4402 ---------------------------------
4404 * allowing negative levels (as offsets) in prlev and choplev;
4406 * super-linear speedup for large simplifications;
4408 * FOL, ZF and HOL now use miniscoping: rewriting pushes
4409 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
4410 FAIL); can suppress it using the command Delsimps (ex_simps @
4411 all_simps); De Morgan laws are also now included, by default;
4413 * improved printing of ==> : ~:
4415 * new object-logic "Sequents" adds linear logic, while replacing LK
4416 and Modal (thanks to Sara Kalvala);
4418 * HOL/Auth: correctness proofs for authentication protocols;
4420 * HOL: new auto_tac combines rewriting and classical reasoning (many
4421 examples on HOL/Auth);
4423 * HOL: new command AddIffs for declaring theorems of the form P=Q to
4424 the rewriter and classical reasoner simultaneously;
4426 * function uresult no longer returns theorems in "standard" format;
4427 regain previous version by: val uresult = standard o uresult;
4431 New in Isabelle94-6
4432 -------------------
4434 * oracles -- these establish an interface between Isabelle and trusted
4435 external reasoners, which may deliver results as theorems;
4437 * proof objects (in particular record all uses of oracles);
4439 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
4441 * "constdefs" section in theory files;
4443 * "primrec" section (HOL) no longer requires names;
4445 * internal type "tactic" now simply "thm -> thm Sequence.seq";
4449 New in Isabelle94-5
4450 -------------------
4452 * reduced space requirements;
4454 * automatic HTML generation from theories;
4456 * theory files no longer require "..." (quotes) around most types;
4458 * new examples, including two proofs of the Church-Rosser theorem;
4460 * non-curried (1994) version of HOL is no longer distributed;
4464 New in Isabelle94-4
4465 -------------------
4467 * greatly reduced space requirements;
4469 * theory files (.thy) no longer require \...\ escapes at line breaks;
4471 * searchable theorem database (see the section "Retrieving theorems" on
4472 page 8 of the Reference Manual);
4474 * new examples, including Grabczewski's monumental case study of the
4475 Axiom of Choice;
4477 * The previous version of HOL renamed to Old_HOL;
4479 * The new version of HOL (previously called CHOL) uses a curried syntax
4480 for functions. Application looks like f a b instead of f(a,b);
4482 * Mutually recursive inductive definitions finally work in HOL;
4484 * In ZF, pattern-matching on tuples is now available in all abstractions and
4485 translates to the operator "split";
4489 New in Isabelle94-3
4490 -------------------
4492 * new infix operator, addss, allowing the classical reasoner to
4493 perform simplification at each step of its search. Example:
4494 fast_tac (cs addss ss)
4496 * a new logic, CHOL, the same as HOL, but with a curried syntax
4497 for functions. Application looks like f a b instead of f(a,b). Also pairs
4498 look like (a,b) instead of <a,b>;
4500 * PLEASE NOTE: CHOL will eventually replace HOL!
4502 * In CHOL, pattern-matching on tuples is now available in all abstractions.
4503 It translates to the operator "split". A new theory of integers is available;
4505 * In ZF, integer numerals now denote two's-complement binary integers.
4506 Arithmetic operations can be performed by rewriting. See ZF/ex/Bin.ML;
4508 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
4509 of the Axiom of Choice;
4513 New in Isabelle94-2
4514 -------------------
4516 * Significantly faster resolution;
4518 * the different sections in a .thy file can now be mixed and repeated
4519 freely;
4521 * Database of theorems for FOL, HOL and ZF. New
4522 commands including qed, qed_goal and bind_thm store theorems in the database.
4524 * Simple database queries: return a named theorem (get_thm) or all theorems of
4525 a given theory (thms_of), or find out what theory a theorem was proved in
4526 (theory_of_thm);
4528 * Bugs fixed in the inductive definition and datatype packages;
4530 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
4531 and HOL_dup_cs obsolete;
4533 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
4534 have been removed;
4536 * Simpler definition of function space in ZF;
4538 * new results about cardinal and ordinal arithmetic in ZF;
4540 * 'subtype' facility in HOL for introducing new types as subsets of existing
4541 types;
4544 $Id$