NEWS
author wenzelm
Wed Jul 23 11:03:54 1997 +0200 (1997-07-23)
changeset 3557 9546f8185c43
parent 3535 19bd6c8274c4
child 3561 329441e7eeee
permissions -rw-r--r--
added simplification meta rules;
     1 
     2 Isabelle NEWS -- history of user-visible changes
     3 ================================================
     4 
     5 New in Isabelle???? (DATE ????)
     6 -------------------------------
     7 
     8 * removed old README and Makefiles;
     9 
    10 * removed obsolete init_pps and init_database;
    11 
    12 * defs may now be conditional;
    13 
    14 * improved output of warnings / errors;
    15 
    16 
    17 New in Isabelle94-8 (May 1997)
    18 ------------------------------
    19 
    20 *** General Changes ***
    21 
    22 * new utilities to build / run / maintain Isabelle etc. (in parts
    23 still somewhat experimental); old Makefiles etc. still functional;
    24 
    25 * new 'Isabelle System Manual';
    26 
    27 * INSTALL text, together with ./configure and ./build scripts;
    28 
    29 * reimplemented type inference for greater efficiency, better error
    30 messages and clean internal interface;
    31 
    32 * prlim command for dealing with lots of subgoals (an easier way of
    33 setting goals_limit);
    34 
    35 
    36 *** Syntax ***
    37 
    38 * supports alternative (named) syntax tables (parser and pretty
    39 printer); internal interface is provided by add_modesyntax(_i);
    40 
    41 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
    42 be used in conjunction with the Isabelle symbol font; uses the
    43 "symbols" syntax table;
    44 
    45 * added token_translation interface (may translate name tokens in
    46 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
    47 the current print_mode); IMPORTANT: user print translation functions
    48 are responsible for marking newly introduced bounds
    49 (Syntax.mark_boundT);
    50 
    51 * token translations for modes "xterm" and "xterm_color" that display
    52 names in bold, underline etc. or colors (which requires a color
    53 version of xterm);
    54 
    55 * infixes may now be declared with names independent of their syntax;
    56 
    57 * added typed_print_translation (like print_translation, but may
    58 access type of constant);
    59 
    60 
    61 *** Classical Reasoner ***
    62 
    63 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
    64 some limitations.  Blast_tac...
    65   + ignores addss, addbefore, addafter; this restriction is intrinsic
    66   + ignores elimination rules that don't have the correct format
    67 	(the conclusion MUST be a formula variable)
    68   + ignores types, which can make HOL proofs fail
    69   + rules must not require higher-order unification, e.g. apply_type in ZF
    70     [message "Function Var's argument not a bound variable" relates to this]
    71   + its proof strategy is more general but can actually be slower
    72 
    73 * substitution with equality assumptions no longer permutes other
    74 assumptions;
    75 
    76 * minor changes in semantics of addafter (now called addaltern); renamed
    77 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
    78 (and access functions for it);
    79 
    80 * improved combination of classical reasoner and simplifier: 
    81   + functions for handling clasimpsets
    82   + improvement of addss: now the simplifier is called _after_ the
    83     safe steps.
    84   + safe variant of addss called addSss: uses safe simplifications
    85     _during_ the safe steps. It is more complete as it allows multiple 
    86     instantiations of unknowns (e.g. with slow_tac).
    87 
    88 *** Simplifier ***
    89 
    90 * added interface for simplification procedures (functions that
    91 produce *proven* rewrite rules on the fly, depending on current
    92 redex);
    93 
    94 * ordering on terms as parameter (used for ordered rewriting);
    95 
    96 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
    97 
    98 * the solver is now split into a safe and an unsafe part.
    99 This should be invisible for the normal user, except that the
   100 functions setsolver and addsolver have been renamed to setSolver and
   101 addSolver; added safe_asm_full_simp_tac;
   102 
   103 
   104 *** HOL ***
   105 
   106 * a generic induction tactic `induct_tac' which works for all datatypes and
   107 also for type `nat';
   108 
   109 * a generic case distinction tactic `exhaust_tac' which works for all
   110 datatypes and also for type `nat';
   111 
   112 * each datatype comes with a function `size';
   113 
   114 * patterns in case expressions allow tuple patterns as arguments to
   115 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
   116 
   117 * primrec now also works with type nat;
   118 
   119 * recdef: a new declaration form, allows general recursive functions to be
   120 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
   121 
   122 * the constant for negation has been renamed from "not" to "Not" to
   123 harmonize with FOL, ZF, LK, etc.;
   124 
   125 * HOL/ex/LFilter theory of a corecursive "filter" functional for
   126 infinite lists;
   127 
   128 * HOL/Modelcheck demonstrates invocation of model checker oracle;
   129 
   130 * HOL/ex/Ring.thy declares cring_simp, which solves equational
   131 problems in commutative rings, using axiomatic type classes for + and *;
   132 
   133 * more examples in HOL/MiniML and HOL/Auth;
   134 
   135 * more default rewrite rules for quantifiers, union/intersection;
   136 
   137 * a new constant `arbitrary == @x.False';
   138 
   139 * HOLCF/IOA replaces old HOL/IOA;
   140 
   141 * HOLCF changes: derived all rules and arities 
   142   + axiomatic type classes instead of classes 
   143   + typedef instead of faking type definitions
   144   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
   145   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
   146   + eliminated the types void, one, tr
   147   + use unit lift and bool lift (with translations) instead of one and tr
   148   + eliminated blift from Lift3.thy (use Def instead of blift)
   149   all eliminated rules are derived as theorems --> no visible changes ;
   150 
   151 
   152 *** ZF ***
   153 
   154 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
   155 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
   156 as ZF_cs addSIs [equalityI];
   157 
   158 
   159 
   160 New in Isabelle94-7 (November 96)
   161 ---------------------------------
   162 
   163 * allowing negative levels (as offsets) in prlev and choplev;
   164 
   165 * super-linear speedup for large simplifications;
   166 
   167 * FOL, ZF and HOL now use miniscoping: rewriting pushes
   168 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
   169 FAIL); can suppress it using the command Delsimps (ex_simps @
   170 all_simps); De Morgan laws are also now included, by default;
   171 
   172 * improved printing of ==>  :  ~:
   173 
   174 * new object-logic "Sequents" adds linear logic, while replacing LK
   175 and Modal (thanks to Sara Kalvala);
   176 
   177 * HOL/Auth: correctness proofs for authentication protocols;
   178 
   179 * HOL: new auto_tac combines rewriting and classical reasoning (many
   180 examples on HOL/Auth);
   181 
   182 * HOL: new command AddIffs for declaring theorems of the form P=Q to
   183 the rewriter and classical reasoner simultaneously;
   184 
   185 * function uresult no longer returns theorems in "standard" format;
   186 regain previous version by: val uresult = standard o uresult;
   187 
   188 
   189 
   190 New in Isabelle94-6
   191 -------------------
   192 
   193 * oracles -- these establish an interface between Isabelle and trusted
   194 external reasoners, which may deliver results as theorems;
   195 
   196 * proof objects (in particular record all uses of oracles);
   197 
   198 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
   199 
   200 * "constdefs" section in theory files;
   201 
   202 * "primrec" section (HOL) no longer requires names;
   203 
   204 * internal type "tactic" now simply "thm -> thm Sequence.seq";
   205 
   206 
   207 
   208 New in Isabelle94-5
   209 -------------------
   210 
   211 * reduced space requirements;
   212 
   213 * automatic HTML generation from theories;
   214 
   215 * theory files no longer require "..." (quotes) around most types;
   216 
   217 * new examples, including two proofs of the Church-Rosser theorem;
   218 
   219 * non-curried (1994) version of HOL is no longer distributed;
   220 
   221 
   222 
   223 New in Isabelle94-4
   224 -------------------
   225 
   226 * greatly reduced space requirements;
   227 
   228 * theory files (.thy) no longer require \...\ escapes at line breaks;
   229 
   230 * searchable theorem database (see the section "Retrieving theorems" on 
   231 page 8 of the Reference Manual);
   232 
   233 * new examples, including Grabczewski's monumental case study of the
   234 Axiom of Choice;
   235 
   236 * The previous version of HOL renamed to Old_HOL;
   237 
   238 * The new version of HOL (previously called CHOL) uses a curried syntax 
   239 for functions.  Application looks like f a b instead of f(a,b);
   240 
   241 * Mutually recursive inductive definitions finally work in HOL;
   242 
   243 * In ZF, pattern-matching on tuples is now available in all abstractions and
   244 translates to the operator "split";
   245 
   246 
   247 
   248 New in Isabelle94-3
   249 -------------------
   250 
   251 * new infix operator, addss, allowing the classical reasoner to 
   252 perform simplification at each step of its search.  Example:
   253 	fast_tac (cs addss ss)
   254 
   255 * a new logic, CHOL, the same as HOL, but with a curried syntax 
   256 for functions.  Application looks like f a b instead of f(a,b).  Also pairs 
   257 look like (a,b) instead of <a,b>;
   258 
   259 * PLEASE NOTE: CHOL will eventually replace HOL!
   260 
   261 * In CHOL, pattern-matching on tuples is now available in all abstractions.
   262 It translates to the operator "split".  A new theory of integers is available;
   263 
   264 * In ZF, integer numerals now denote two's-complement binary integers.
   265 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
   266 
   267 * Many new examples: I/O automata, Church-Rosser theorem, equivalents 
   268 of the Axiom of Choice;
   269 
   270 
   271 
   272 New in Isabelle94-2
   273 -------------------
   274 
   275 * Significantly faster resolution;  
   276 
   277 * the different sections in a .thy file can now be mixed and repeated
   278 freely;
   279 
   280 * Database of theorems for FOL, HOL and ZF.  New
   281 commands including qed, qed_goal and bind_thm store theorems in the database.
   282 
   283 * Simple database queries: return a named theorem (get_thm) or all theorems of
   284 a given theory (thms_of), or find out what theory a theorem was proved in
   285 (theory_of_thm);
   286 
   287 * Bugs fixed in the inductive definition and datatype packages;
   288 
   289 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
   290 and HOL_dup_cs obsolete;
   291 
   292 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
   293 have been removed;
   294 
   295 * Simpler definition of function space in ZF;
   296 
   297 * new results about cardinal and ordinal arithmetic in ZF;
   298 
   299 * 'subtype' facility in HOL for introducing new types as subsets of existing
   300 types;
   301 
   302 
   303 $Id$