NEWS
author paulson
Tue Sep 15 15:04:07 1998 +0200 (1998-09-15)
changeset 5490 85855f65d0c6
parent 5475 410172655d64
child 5524 38f2a518a811
permissions -rw-r--r--
From Compl(A) to -A
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Isabelle NEWS -- history user-relevant changes
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==============================================
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New in this Isabelle version
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----------------------------
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*** Overview of INCOMPATIBILITIES (see below for more details) ***
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* several changes of proof tools;
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* HOL: new version of inductive and datatype;
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* HOL: major changes to the inductive and datatype packages;
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* HOL: renamed r^-1 to 'converse' from 'inverse'; `inj_onto' is now
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called `inj_on';
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* HOL: removed duplicate thms in Arith:
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  less_imp_add_less  should be replaced by  trans_less_add1
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  le_imp_add_le      should be replaced by  trans_le_add1
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* HOL: unary - is now overloaded (new type constraints may be required);
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* Pure: ML function 'theory_of' replaced by 'theory';
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*** Proof tools ***
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* Simplifier: Asm_full_simp_tac is now more aggressive.
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  1. It will sometimes reorient premises if that increases their power to
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     simplify.
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  2. It does no longer proceed strictly from left to right but may also
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     rotate premises to achieve further simplification.
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  For compatibility reasons there is now Asm_lr_simp_tac which is like the
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  old Asm_full_simp_tac in that it does not rotate premises.
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* Classical reasoner: wrapper mechanism for the classical reasoner now
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allows for selected deletion of wrappers, by introduction of names for
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wrapper functionals.  This implies that addbefore, addSbefore,
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addaltern, and addSaltern now take a pair (name, tactic) as argument,
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and that adding two tactics with the same name overwrites the first
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one (emitting a warning).
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  type wrapper = (int -> tactic) -> (int -> tactic)
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  setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
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  addWrapper, addSWrapper: claset * (string * wrapper) -> claset
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  delWrapper, delSWrapper: claset *  string            -> claset
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  getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
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* HOL/split_all_tac is now much faster and fails if there is nothing
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to split.  Existing (fragile) proofs may require adaption because the
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order and the names of the automatically generated variables have
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changed.  split_all_tac has moved within claset() from unsafe wrappers
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to safe wrappers, which means that !!-bound variables are split much
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more aggressively, and safe_tac and clarify_tac now split such
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variables.  If this splitting is not appropriate, use delSWrapper
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"split_all_tac".
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* HOL/Simplifier:
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 - Rewrite rules for case distinctions can now be added permanently to
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   the default simpset using Addsplits just like Addsimps. They can be
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   removed via Delsplits just like Delsimps. Lower-case versions are
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   also available.
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 - The rule split_if is now part of the default simpset. This means
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   that the simplifier will eliminate all occurrences of if-then-else
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   in the conclusion of a goal. To prevent this, you can either remove
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   split_if completely from the default simpset by `Delsplits
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   [split_if]' or remove it in a specific call of the simplifier using
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   `... delsplits [split_if]'.  You can also add/delete other case
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   splitting rules to/from the default simpset: every datatype
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   generates suitable rules `split_t_case' and `split_t_case_asm'
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   (where t is the name of the datatype).
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* Classical reasoner - Simplifier combination: new force_tac (and
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derivatives Force_tac, force) combines rewriting and classical
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reasoning (and whatever other tools) similarly to auto_tac, but is
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aimed to solve the given subgoal completely;
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*** General ***
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* new top-level commands `Goal' and `Goalw' that improve upon `goal'
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and `goalw': the theory is no longer needed as an explicit argument -
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the current theory context is used; assumptions are no longer returned
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at the ML-level unless one of them starts with ==> or !!; it is
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recommended to convert to these new commands using isatool fixgoal
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(backup your sources first!);
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* new top-level commands 'thm' and 'thms' for retrieving theorems from
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the current theory context, and 'theory' to lookup stored theories;
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* new theory section 'nonterminals' for purely syntactic types;
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* new theory section 'setup' for generic ML setup functions
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(e.g. package initialization);
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* the distribution now includes Isabelle icons: see
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lib/logo/isabelle-{small,tiny}.xpm;
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* isatool install - install binaries with absolute references to
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ISABELLE_HOME/bin;
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* print mode 'emacs' reserved for Isamode;
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*** HOL ***
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* HOL/inductive package reorganized and improved: now supports mutual
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definitions such as
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  inductive EVEN ODD
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    intrs
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      null "0 : EVEN"
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      oddI "n : EVEN ==> Suc n : ODD"
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      evenI "n : ODD ==> Suc n : EVEN"
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new theorem list "elims" contains an elimination rule for each of the
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recursive sets; inductive definitions now handle disjunctive premises
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correctly (also ZF);
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INCOMPATIBILITIES: requires Inductive as an ancestor; component
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"mutual_induct" no longer exists - the induction rule is always
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contained in "induct";
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* HOL/datatype package re-implemented and greatly improved: now
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supports mutually recursive datatypes such as
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  datatype
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    'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
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            | SUM ('a aexp) ('a aexp)
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            | DIFF ('a aexp) ('a aexp)
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            | NUM 'a
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  and
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    'a bexp = LESS ('a aexp) ('a aexp)
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            | AND ('a bexp) ('a bexp)
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            | OR ('a bexp) ('a bexp)
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as well as indirectly recursive datatypes such as
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  datatype
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    ('a, 'b) term = Var 'a
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                  | App 'b ((('a, 'b) term) list)
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The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
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induction on mutually / indirectly recursive datatypes.
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Primrec equations are now stored in theory and can be accessed via
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<function_name>.simps.
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INCOMPATIBILITIES:
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  - Theories using datatypes must now have theory Datatype as an
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    ancestor.
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  - The specific <typename>.induct_tac no longer exists - use the
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    generic induct_tac instead.
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  - natE has been renamed to nat.exhaust - use exhaust_tac
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    instead of res_inst_tac ... natE. Note that the variable
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    names in nat.exhaust differ from the names in natE, this
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    may cause some "fragile" proofs to fail.
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  - The theorems split_<typename>_case and split_<typename>_case_asm
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    have been renamed to <typename>.split and <typename>.split_asm.
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  - Since default sorts of type variables are now handled correctly,
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    some datatype definitions may have to be annotated with explicit
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    sort constraints.
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  - Primrec definitions no longer require function name and type
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    of recursive argument.
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Consider using isatool fixdatatype to adapt your theories and proof
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scripts to the new package (backup your sources first!).
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* HOL/record package: now includes concrete syntax for record types,
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terms, updates; still lacks important theorems, like surjective
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pairing and split;
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* reorganized the main HOL image: HOL/Integ and String loaded by
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default; theory Main includes everything;
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* added option_map_eq_Some to the default simpset claset;
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* added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
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* many new identities for unions, intersections, set difference, etc.;
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* expand_if, expand_split, expand_sum_case and expand_nat_case are now
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called split_if, split_split, split_sum_case and split_nat_case (to go
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with add/delsplits);
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* HOL/Prod introduces simplification procedure unit_eq_proc rewriting
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(?x::unit) = (); this is made part of the default simpset, which COULD
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MAKE EXISTING PROOFS FAIL under rare circumstances (consider
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'Delsimprocs [unit_eq_proc];' as last resort); also note that
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unit_abs_eta_conv is added in order to counter the effect of
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unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
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%u.f();
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* HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
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makes more sense);
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* HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
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  It and 'sym RS equals0D' are now in the default  claset, giving automatic
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  disjointness reasoning but breaking a few old proofs.
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* HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
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to 'converse' from 'inverse' (for compatibility with ZF and some
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literature);
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* HOL/recdef can now declare non-recursive functions, with {} supplied as
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the well-founded relation;
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* HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
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    Compl A.  The "Compl" syntax remains available as input syntax for this
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    release ONLY.
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* HOL/Update: new theory of function updates:
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    f(a:=b) == %x. if x=a then b else f x
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may also be iterated as in f(a:=b,c:=d,...);
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* HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
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* HOL/List:
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  - new function list_update written xs[i:=v] that updates the i-th
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    list position. May also be iterated as in xs[i:=a,j:=b,...].
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  - new function `upt' written [i..j(] which generates the list
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    [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
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    bound write [i..j], which is a shorthand for [i..j+1(].
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  - new lexicographic orderings and corresponding wellfoundedness theorems.
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* HOL/Arith:
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  - removed 'pred' (predecessor) function;
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  - generalized some theorems about n-1;
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  - many new laws about "div" and "mod";
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  - new laws about greatest common divisors (see theory ex/Primes);
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* HOL/Relation: renamed the relational operator r^-1 "converse"
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instead of "inverse";
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* directory HOL/Real: a construction of the reals using Dedekind cuts
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(not included by default);
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* directory HOL/UNITY: Chandy and Misra's UNITY formalism;
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* calling (stac rew i) now fails if "rew" has no effect on the goal
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  [previously, this check worked only if the rewrite rule was unconditional]
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  Now rew can involve either definitions or equalities (either == or =).
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*** ZF ***
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* theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
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  only the theorems proved on ZF.ML;
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* ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
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  It and 'sym RS equals0D' are now in the default  claset, giving automatic
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  disjointness reasoning but breaking a few old proofs.
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* ZF/Update: new theory of function updates
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    with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
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  may also be iterated as in f(a:=b,c:=d,...);
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* in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
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* calling (stac rew i) now fails if "rew" has no effect on the goal
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  [previously, this check worked only if the rewrite rule was unconditional]
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  Now rew can involve either definitions or equalities (either == or =).
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* case_tac provided for compatibility with HOL
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    (like the old excluded_middle_tac, but with subgoals swapped)
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*** Internal programming interfaces ***
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* Pure: several new basic modules made available for general use, see
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also src/Pure/README;
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* improved the theory data mechanism to support encapsulation (data
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kind name replaced by private Object.kind, acting as authorization
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key); new type-safe user interface via functor TheoryDataFun; generic
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print_data function becomes basically useless;
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* removed global_names compatibility flag -- all theory declarations
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are qualified by default;
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* module Pure/Syntax now offers quote / antiquote translation
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functions (useful for Hoare logic etc. with implicit dependencies);
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see HOL/ex/Antiquote for an example use;
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* Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
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cterm -> thm;
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* new tactical CHANGED_GOAL for checking that a tactic modifies a
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subgoal;
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* Display.print_goals function moved to Locale.print_goals;
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New in Isabelle98 (January 1998)
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--------------------------------
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*** Overview of INCOMPATIBILITIES (see below for more details) ***
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* changed lexical syntax of terms / types: dots made part of long
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identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
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* simpset (and claset) reference variable replaced by functions
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simpset / simpset_ref;
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* no longer supports theory aliases (via merge) and non-trivial
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implicit merge of thms' signatures;
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* most internal names of constants changed due to qualified names;
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* changed Pure/Sequence interface (see Pure/seq.ML);
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*** General Changes ***
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* hierachically structured name spaces (for consts, types, axms, thms
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etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
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old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
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isatool fixdots ensures space after dots (e.g. "%x. x"); set
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long_names for fully qualified output names; NOTE: ML programs
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(special tactics, packages etc.) referring to internal names may have
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to be adapted to cope with fully qualified names; in case of severe
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backward campatibility problems try setting 'global_names' at compile
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time to have enrything declared within a flat name space; one may also
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fine tune name declarations in theories via the 'global' and 'local'
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section;
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* reimplemented the implicit simpset and claset using the new anytype
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data filed in signatures; references simpset:simpset ref etc. are
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replaced by functions simpset:unit->simpset and
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simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
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to patch your ML files accordingly;
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* HTML output now includes theory graph data for display with Java
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applet or isatool browser; data generated automatically via isatool
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usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
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* defs may now be conditional; improved rewrite_goals_tac to handle
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conditional equations;
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wenzelm@4174
   347
* defs now admits additional type arguments, using TYPE('a) syntax;
wenzelm@4174
   348
wenzelm@3901
   349
* theory aliases via merge (e.g. M=A+B+C) no longer supported, always
wenzelm@3901
   350
creates a new theory node; implicit merge of thms' signatures is
wenzelm@4112
   351
restricted to 'trivial' ones; COMPATIBILITY: one may have to use
wenzelm@3901
   352
transfer:theory->thm->thm in (rare) cases;
wenzelm@3901
   353
wenzelm@3968
   354
* improved handling of draft signatures / theories; draft thms (and
wenzelm@3968
   355
ctyps, cterms) are automatically promoted to real ones;
wenzelm@3968
   356
wenzelm@3901
   357
* slightly changed interfaces for oracles: admit many per theory, named
wenzelm@3901
   358
(e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
wenzelm@3901
   359
wenzelm@3901
   360
* print_goals: optional output of const types (set show_consts and
wenzelm@3901
   361
show_types);
wenzelm@3851
   362
wenzelm@4388
   363
* improved output of warnings (###) and errors (***);
wenzelm@3697
   364
paulson@4178
   365
* subgoal_tac displays a warning if the new subgoal has type variables;
paulson@4178
   366
paulson@3715
   367
* removed old README and Makefiles;
wenzelm@3697
   368
paulson@3856
   369
* replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
wenzelm@3670
   370
paulson@3715
   371
* removed obsolete init_pps and init_database;
paulson@3715
   372
paulson@3715
   373
* deleted the obsolete tactical STATE, which was declared by
paulson@3715
   374
    fun STATE tacfun st = tacfun st st;
paulson@3715
   375
wenzelm@4388
   376
* cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
wenzelm@4388
   377
(which abbreviates $HOME);
wenzelm@4269
   378
wenzelm@4269
   379
* changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
wenzelm@4269
   380
use isatool fixseq to adapt your ML programs (this works for fully
wenzelm@4269
   381
qualified references to the Sequence structure only!);
wenzelm@4269
   382
wenzelm@4381
   383
* use_thy no longer requires writable current directory; it always
wenzelm@4381
   384
reloads .ML *and* .thy file, if either one is out of date;
wenzelm@4269
   385
paulson@3715
   386
paulson@3715
   387
*** Classical Reasoner ***
paulson@3715
   388
wenzelm@3744
   389
* Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
wenzelm@3744
   390
tactics that use classical reasoning to simplify a subgoal without
wenzelm@3744
   391
splitting it into several subgoals;
paulson@3715
   392
paulson@3719
   393
* Safe_tac: like safe_tac but uses the default claset;
paulson@3719
   394
paulson@3715
   395
paulson@3715
   396
*** Simplifier ***
paulson@3715
   397
paulson@3715
   398
* added simplification meta rules:
paulson@3715
   399
    (asm_)(full_)simplify: simpset -> thm -> thm;
paulson@3715
   400
paulson@3715
   401
* simplifier.ML no longer part of Pure -- has to be loaded by object
paulson@3715
   402
logics (again);
paulson@3715
   403
paulson@3715
   404
* added prems argument to simplification procedures;
paulson@3715
   405
paulson@4325
   406
* HOL, FOL, ZF: added infix function `addsplits':
paulson@4325
   407
  instead of `<simpset> setloop (split_tac <thms>)'
paulson@4325
   408
  you can simply write `<simpset> addsplits <thms>'
paulson@4325
   409
paulson@3715
   410
paulson@3715
   411
*** Syntax ***
paulson@3715
   412
wenzelm@4174
   413
* TYPE('a) syntax for type reflection terms;
wenzelm@4174
   414
wenzelm@3985
   415
* no longer handles consts with name "" -- declare as 'syntax' instead;
paulson@3856
   416
paulson@3856
   417
* pretty printer: changed order of mixfix annotation preference (again!);
wenzelm@3846
   418
paulson@3715
   419
* Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
paulson@3715
   420
paulson@3715
   421
paulson@3715
   422
*** HOL ***
paulson@3715
   423
oheimb@4207
   424
* HOL: there is a new splitter `split_asm_tac' that can be used e.g. 
oheimb@4189
   425
  with `addloop' of the simplifier to faciliate case splitting in premises.
oheimb@4189
   426
nipkow@4035
   427
* HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
wenzelm@3985
   428
wenzelm@3985
   429
* HOL/Auth: new protocol proofs including some for the Internet
nipkow@4035
   430
  protocol TLS;
wenzelm@3985
   431
wenzelm@4125
   432
* HOL/Map: new theory of `maps' a la VDM;
nipkow@3982
   433
wenzelm@4335
   434
* HOL/simplifier: simplification procedures nat_cancel_sums for
wenzelm@4335
   435
cancelling out common nat summands from =, <, <= (in)equalities, or
wenzelm@4335
   436
differences; simplification procedures nat_cancel_factor for
wenzelm@4335
   437
cancelling common factor from =, <, <= (in)equalities over natural
wenzelm@4373
   438
sums; nat_cancel contains both kinds of procedures, it is installed by
wenzelm@4373
   439
default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
wenzelm@4335
   440
nipkow@3580
   441
* HOL/simplifier: terms of the form
paulson@4325
   442
  `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
nipkow@3580
   443
  are rewritten to
nipkow@4035
   444
  `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
nipkow@4035
   445
  and those of the form
paulson@4325
   446
  `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
nipkow@4035
   447
  are rewritten to
nipkow@4035
   448
  `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
nipkow@4035
   449
nipkow@4035
   450
* HOL/datatype
nipkow@4035
   451
  Each datatype `t' now comes with a theorem `split_t_case' of the form
nipkow@3580
   452
nipkow@4035
   453
  P(t_case f1 ... fn x) =
nipkow@4035
   454
     ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
nipkow@4035
   455
        ...
oheimb@4189
   456
       (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
nipkow@4035
   457
     )
nipkow@4035
   458
oheimb@4930
   459
  and a theorem `split_t_case_asm' of the form
oheimb@4189
   460
oheimb@4189
   461
  P(t_case f1 ... fn x) =
oheimb@4189
   462
    ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
oheimb@4189
   463
        ...
oheimb@4189
   464
       (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
oheimb@4189
   465
     )
oheimb@4930
   466
  which can be added to a simpset via `addsplits'. The existing theorems
oheimb@4930
   467
  expand_list_case and expand_option_case have been renamed to
oheimb@4930
   468
  split_list_case and split_option_case.
oheimb@4189
   469
nipkow@4361
   470
* HOL/Arithmetic:
nipkow@4361
   471
  - `pred n' is automatically converted to `n-1'.
nipkow@4361
   472
    Users are strongly encouraged not to use `pred' any longer,
nipkow@4361
   473
    because it will disappear altogether at some point.
nipkow@4361
   474
  - Users are strongly encouraged to write "0 < n" rather than
nipkow@4361
   475
    "n ~= 0". Theorems and proof tools have been modified towards this
nipkow@4361
   476
    `standard'.
nipkow@4357
   477
nipkow@4502
   478
* HOL/Lists:
nipkow@4502
   479
  the function "set_of_list" has been renamed "set" (and its theorems too);
nipkow@4502
   480
  the function "nth" now takes its arguments in the reverse order and
nipkow@4502
   481
  has acquired the infix notation "!" as in "xs!n".
paulson@3570
   482
paulson@4154
   483
* HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
paulson@4154
   484
paulson@4154
   485
* HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
paulson@4154
   486
  specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
paulson@4154
   487
wenzelm@4575
   488
* HOL/record: extensible records with schematic structural subtyping
wenzelm@4575
   489
(single inheritance); EXPERIMENTAL version demonstrating the encoding,
wenzelm@4575
   490
still lacks various theorems and concrete record syntax;
wenzelm@4575
   491
wenzelm@4125
   492
paulson@3715
   493
*** HOLCF ***
wenzelm@3535
   494
wenzelm@4125
   495
* removed "axioms" and "generated by" sections;
wenzelm@4125
   496
oheimb@4123
   497
* replaced "ops" section by extended "consts" section, which is capable of
wenzelm@4125
   498
  handling the continuous function space "->" directly;
wenzelm@4125
   499
wenzelm@4125
   500
* domain package:
wenzelm@4125
   501
  . proves theorems immediately and stores them in the theory,
wenzelm@4125
   502
  . creates hierachical name space,
wenzelm@4125
   503
  . now uses normal mixfix annotations (instead of cinfix...),
wenzelm@4125
   504
  . minor changes to some names and values (for consistency),
wenzelm@4125
   505
  . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
wenzelm@4125
   506
  . separator between mutual domain defs: changed "," to "and",
wenzelm@4125
   507
  . improved handling of sort constraints;  now they have to
wenzelm@4125
   508
    appear on the left-hand side of the equations only;
oheimb@4123
   509
oheimb@4123
   510
* fixed LAM <x,y,zs>.b syntax;
wenzelm@3567
   511
wenzelm@3744
   512
* added extended adm_tac to simplifier in HOLCF -- can now discharge
wenzelm@3744
   513
adm (%x. P (t x)), where P is chainfinite and t continuous;
wenzelm@3579
   514
wenzelm@3579
   515
paulson@3719
   516
*** FOL and ZF ***
paulson@3719
   517
oheimb@4207
   518
* FOL: there is a new splitter `split_asm_tac' that can be used e.g. 
oheimb@4189
   519
  with `addloop' of the simplifier to faciliate case splitting in premises.
oheimb@4189
   520
wenzelm@3744
   521
* qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
wenzelm@3744
   522
in HOL, they strip ALL and --> from proved theorems;
wenzelm@3744
   523
paulson@3719
   524
wenzelm@3579
   525
wenzelm@3006
   526
New in Isabelle94-8 (May 1997)
wenzelm@3006
   527
------------------------------
wenzelm@2654
   528
paulson@3002
   529
*** General Changes ***
paulson@3002
   530
paulson@3002
   531
* new utilities to build / run / maintain Isabelle etc. (in parts
paulson@3002
   532
still somewhat experimental); old Makefiles etc. still functional;
wenzelm@2971
   533
wenzelm@3205
   534
* new 'Isabelle System Manual';
wenzelm@3205
   535
wenzelm@2825
   536
* INSTALL text, together with ./configure and ./build scripts;
wenzelm@2773
   537
wenzelm@3006
   538
* reimplemented type inference for greater efficiency, better error
wenzelm@3006
   539
messages and clean internal interface;
paulson@3002
   540
paulson@3002
   541
* prlim command for dealing with lots of subgoals (an easier way of
paulson@3002
   542
setting goals_limit);
paulson@3002
   543
wenzelm@3006
   544
wenzelm@3006
   545
*** Syntax ***
paulson@3002
   546
wenzelm@3116
   547
* supports alternative (named) syntax tables (parser and pretty
wenzelm@3116
   548
printer); internal interface is provided by add_modesyntax(_i);
wenzelm@3116
   549
paulson@3002
   550
* Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
paulson@3002
   551
be used in conjunction with the Isabelle symbol font; uses the
paulson@3002
   552
"symbols" syntax table;
paulson@3002
   553
wenzelm@2705
   554
* added token_translation interface (may translate name tokens in
wenzelm@2756
   555
arbitrary ways, dependent on their type (free, bound, tfree, ...) and
wenzelm@3116
   556
the current print_mode); IMPORTANT: user print translation functions
wenzelm@3116
   557
are responsible for marking newly introduced bounds
wenzelm@3116
   558
(Syntax.mark_boundT);
wenzelm@2705
   559
wenzelm@2730
   560
* token translations for modes "xterm" and "xterm_color" that display
wenzelm@3006
   561
names in bold, underline etc. or colors (which requires a color
wenzelm@3006
   562
version of xterm);
wenzelm@2730
   563
paulson@3002
   564
* infixes may now be declared with names independent of their syntax;
paulson@3002
   565
paulson@3002
   566
* added typed_print_translation (like print_translation, but may
paulson@3002
   567
access type of constant);
paulson@3002
   568
wenzelm@3006
   569
paulson@3002
   570
*** Classical Reasoner ***
paulson@3002
   571
paulson@3002
   572
Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
paulson@3002
   573
some limitations.  Blast_tac...
paulson@3002
   574
  + ignores addss, addbefore, addafter; this restriction is intrinsic
paulson@3002
   575
  + ignores elimination rules that don't have the correct format
paulson@3002
   576
	(the conclusion MUST be a formula variable)
paulson@3002
   577
  + ignores types, which can make HOL proofs fail
paulson@3002
   578
  + rules must not require higher-order unification, e.g. apply_type in ZF
paulson@3002
   579
    [message "Function Var's argument not a bound variable" relates to this]
paulson@3002
   580
  + its proof strategy is more general but can actually be slower
paulson@3002
   581
wenzelm@3107
   582
* substitution with equality assumptions no longer permutes other
wenzelm@3107
   583
assumptions;
paulson@3002
   584
paulson@3002
   585
* minor changes in semantics of addafter (now called addaltern); renamed
paulson@3002
   586
setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
wenzelm@3107
   587
(and access functions for it);
paulson@3002
   588
oheimb@3317
   589
* improved combination of classical reasoner and simplifier: 
oheimb@3317
   590
  + functions for handling clasimpsets
oheimb@3317
   591
  + improvement of addss: now the simplifier is called _after_ the
oheimb@3317
   592
    safe steps.
oheimb@3317
   593
  + safe variant of addss called addSss: uses safe simplifications
oheimb@3317
   594
    _during_ the safe steps. It is more complete as it allows multiple 
oheimb@3317
   595
    instantiations of unknowns (e.g. with slow_tac).
wenzelm@3006
   596
paulson@3002
   597
*** Simplifier ***
paulson@3002
   598
wenzelm@3006
   599
* added interface for simplification procedures (functions that
wenzelm@3006
   600
produce *proven* rewrite rules on the fly, depending on current
wenzelm@3006
   601
redex);
wenzelm@3006
   602
wenzelm@3006
   603
* ordering on terms as parameter (used for ordered rewriting);
wenzelm@3006
   604
wenzelm@3107
   605
* new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
paulson@3002
   606
paulson@3002
   607
* the solver is now split into a safe and an unsafe part.
paulson@3002
   608
This should be invisible for the normal user, except that the
paulson@3002
   609
functions setsolver and addsolver have been renamed to setSolver and
wenzelm@3107
   610
addSolver; added safe_asm_full_simp_tac;
paulson@3002
   611
paulson@3002
   612
paulson@3002
   613
*** HOL ***
paulson@3002
   614
nipkow@3042
   615
* a generic induction tactic `induct_tac' which works for all datatypes and
wenzelm@3107
   616
also for type `nat';
nipkow@3042
   617
nipkow@3316
   618
* a generic case distinction tactic `exhaust_tac' which works for all
nipkow@3316
   619
datatypes and also for type `nat';
nipkow@3316
   620
nipkow@3316
   621
* each datatype comes with a function `size';
nipkow@3316
   622
paulson@3002
   623
* patterns in case expressions allow tuple patterns as arguments to
wenzelm@3107
   624
constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
paulson@3002
   625
paulson@3002
   626
* primrec now also works with type nat;
paulson@3002
   627
paulson@3338
   628
* recdef: a new declaration form, allows general recursive functions to be
paulson@3338
   629
defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
paulson@3338
   630
paulson@3002
   631
* the constant for negation has been renamed from "not" to "Not" to
wenzelm@3107
   632
harmonize with FOL, ZF, LK, etc.;
paulson@3002
   633
wenzelm@3107
   634
* HOL/ex/LFilter theory of a corecursive "filter" functional for
wenzelm@3107
   635
infinite lists;
paulson@3002
   636
wenzelm@3227
   637
* HOL/Modelcheck demonstrates invocation of model checker oracle;
wenzelm@3227
   638
paulson@3002
   639
* HOL/ex/Ring.thy declares cring_simp, which solves equational
paulson@3002
   640
problems in commutative rings, using axiomatic type classes for + and *;
paulson@3002
   641
paulson@3002
   642
* more examples in HOL/MiniML and HOL/Auth;
paulson@3002
   643
paulson@3002
   644
* more default rewrite rules for quantifiers, union/intersection;
paulson@3002
   645
nipkow@3321
   646
* a new constant `arbitrary == @x.False';
nipkow@3321
   647
wenzelm@3107
   648
* HOLCF/IOA replaces old HOL/IOA;
wenzelm@3107
   649
slotosch@2653
   650
* HOLCF changes: derived all rules and arities 
slotosch@2653
   651
  + axiomatic type classes instead of classes 
slotosch@2653
   652
  + typedef instead of faking type definitions
paulson@2747
   653
  + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
wenzelm@2730
   654
  + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
slotosch@2653
   655
  + eliminated the types void, one, tr
slotosch@2653
   656
  + use unit lift and bool lift (with translations) instead of one and tr
slotosch@2653
   657
  + eliminated blift from Lift3.thy (use Def instead of blift)
wenzelm@3107
   658
  all eliminated rules are derived as theorems --> no visible changes ;
oheimb@2649
   659
wenzelm@3006
   660
paulson@3002
   661
*** ZF ***
wenzelm@2553
   662
paulson@2865
   663
* ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
paulson@2865
   664
rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
paulson@2865
   665
as ZF_cs addSIs [equalityI];
wenzelm@2553
   666
wenzelm@2554
   667
wenzelm@2732
   668
wenzelm@2553
   669
New in Isabelle94-7 (November 96)
wenzelm@2553
   670
---------------------------------
wenzelm@2553
   671
wenzelm@2553
   672
* allowing negative levels (as offsets) in prlev and choplev;
wenzelm@2553
   673
wenzelm@2554
   674
* super-linear speedup for large simplifications;
wenzelm@2554
   675
wenzelm@2554
   676
* FOL, ZF and HOL now use miniscoping: rewriting pushes
wenzelm@2554
   677
quantifications in as far as possible (COULD MAKE EXISTING PROOFS
wenzelm@2554
   678
FAIL); can suppress it using the command Delsimps (ex_simps @
wenzelm@2554
   679
all_simps); De Morgan laws are also now included, by default;
wenzelm@2554
   680
wenzelm@2554
   681
* improved printing of ==>  :  ~:
wenzelm@2554
   682
wenzelm@2554
   683
* new object-logic "Sequents" adds linear logic, while replacing LK
wenzelm@2554
   684
and Modal (thanks to Sara Kalvala);
wenzelm@2554
   685
wenzelm@2554
   686
* HOL/Auth: correctness proofs for authentication protocols;
wenzelm@2554
   687
wenzelm@2554
   688
* HOL: new auto_tac combines rewriting and classical reasoning (many
wenzelm@2554
   689
examples on HOL/Auth);
wenzelm@2554
   690
wenzelm@2554
   691
* HOL: new command AddIffs for declaring theorems of the form P=Q to
wenzelm@2554
   692
the rewriter and classical reasoner simultaneously;
wenzelm@2554
   693
wenzelm@2554
   694
* function uresult no longer returns theorems in "standard" format;
wenzelm@2554
   695
regain previous version by: val uresult = standard o uresult;
wenzelm@2554
   696
wenzelm@2554
   697
wenzelm@2554
   698
wenzelm@2554
   699
New in Isabelle94-6
wenzelm@2554
   700
-------------------
wenzelm@2554
   701
wenzelm@2554
   702
* oracles -- these establish an interface between Isabelle and trusted
wenzelm@2554
   703
external reasoners, which may deliver results as theorems;
wenzelm@2554
   704
wenzelm@2554
   705
* proof objects (in particular record all uses of oracles);
wenzelm@2554
   706
wenzelm@2554
   707
* Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
wenzelm@2554
   708
wenzelm@2554
   709
* "constdefs" section in theory files;
wenzelm@2554
   710
wenzelm@2554
   711
* "primrec" section (HOL) no longer requires names;
wenzelm@2554
   712
wenzelm@2554
   713
* internal type "tactic" now simply "thm -> thm Sequence.seq";
wenzelm@2554
   714
wenzelm@2554
   715
wenzelm@2554
   716
wenzelm@2554
   717
New in Isabelle94-5
wenzelm@2554
   718
-------------------
wenzelm@2554
   719
wenzelm@2554
   720
* reduced space requirements;
wenzelm@2554
   721
wenzelm@2554
   722
* automatic HTML generation from theories;
wenzelm@2554
   723
wenzelm@2554
   724
* theory files no longer require "..." (quotes) around most types;
wenzelm@2554
   725
wenzelm@2554
   726
* new examples, including two proofs of the Church-Rosser theorem;
wenzelm@2554
   727
wenzelm@2554
   728
* non-curried (1994) version of HOL is no longer distributed;
wenzelm@2554
   729
wenzelm@2553
   730
paulson@2557
   731
paulson@2557
   732
New in Isabelle94-4
paulson@2557
   733
-------------------
paulson@2557
   734
paulson@2747
   735
* greatly reduced space requirements;
paulson@2557
   736
paulson@2557
   737
* theory files (.thy) no longer require \...\ escapes at line breaks;
paulson@2557
   738
paulson@2557
   739
* searchable theorem database (see the section "Retrieving theorems" on 
paulson@2557
   740
page 8 of the Reference Manual);
paulson@2557
   741
paulson@2557
   742
* new examples, including Grabczewski's monumental case study of the
paulson@2557
   743
Axiom of Choice;
paulson@2557
   744
paulson@2557
   745
* The previous version of HOL renamed to Old_HOL;
paulson@2557
   746
paulson@2557
   747
* The new version of HOL (previously called CHOL) uses a curried syntax 
paulson@2557
   748
for functions.  Application looks like f a b instead of f(a,b);
paulson@2557
   749
paulson@2557
   750
* Mutually recursive inductive definitions finally work in HOL;
paulson@2557
   751
paulson@2557
   752
* In ZF, pattern-matching on tuples is now available in all abstractions and
paulson@2557
   753
translates to the operator "split";
paulson@2557
   754
paulson@2557
   755
paulson@2557
   756
paulson@2557
   757
New in Isabelle94-3
paulson@2557
   758
-------------------
paulson@2557
   759
paulson@2557
   760
* new infix operator, addss, allowing the classical reasoner to 
paulson@2557
   761
perform simplification at each step of its search.  Example:
paulson@2557
   762
	fast_tac (cs addss ss)
paulson@2557
   763
paulson@2557
   764
* a new logic, CHOL, the same as HOL, but with a curried syntax 
paulson@2557
   765
for functions.  Application looks like f a b instead of f(a,b).  Also pairs 
paulson@2557
   766
look like (a,b) instead of <a,b>;
paulson@2557
   767
paulson@2557
   768
* PLEASE NOTE: CHOL will eventually replace HOL!
paulson@2557
   769
paulson@2557
   770
* In CHOL, pattern-matching on tuples is now available in all abstractions.
paulson@2557
   771
It translates to the operator "split".  A new theory of integers is available;
paulson@2557
   772
paulson@2557
   773
* In ZF, integer numerals now denote two's-complement binary integers.
paulson@2557
   774
Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
paulson@2557
   775
paulson@2557
   776
* Many new examples: I/O automata, Church-Rosser theorem, equivalents 
paulson@2557
   777
of the Axiom of Choice;
paulson@2557
   778
paulson@2557
   779
paulson@2557
   780
paulson@2557
   781
New in Isabelle94-2
paulson@2557
   782
-------------------
paulson@2557
   783
paulson@2557
   784
* Significantly faster resolution;  
paulson@2557
   785
paulson@2557
   786
* the different sections in a .thy file can now be mixed and repeated
paulson@2557
   787
freely;
paulson@2557
   788
paulson@2557
   789
* Database of theorems for FOL, HOL and ZF.  New
paulson@2557
   790
commands including qed, qed_goal and bind_thm store theorems in the database.
paulson@2557
   791
paulson@2557
   792
* Simple database queries: return a named theorem (get_thm) or all theorems of
paulson@2557
   793
a given theory (thms_of), or find out what theory a theorem was proved in
paulson@2557
   794
(theory_of_thm);
paulson@2557
   795
paulson@2557
   796
* Bugs fixed in the inductive definition and datatype packages;
paulson@2557
   797
paulson@2557
   798
* The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
paulson@2557
   799
and HOL_dup_cs obsolete;
paulson@2557
   800
paulson@2557
   801
* Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
paulson@2557
   802
have been removed;
paulson@2557
   803
paulson@2557
   804
* Simpler definition of function space in ZF;
paulson@2557
   805
paulson@2557
   806
* new results about cardinal and ordinal arithmetic in ZF;
paulson@2557
   807
paulson@2557
   808
* 'subtype' facility in HOL for introducing new types as subsets of existing
paulson@2557
   809
types;
paulson@2557
   810
paulson@2557
   811
wenzelm@2553
   812
$Id$