src/HOL/simpdata.ML
author paulson
Fri Oct 17 11:00:50 1997 +0200 (1997-10-17)
changeset 3913 96e28b16861c
parent 3904 c0d56e4c823e
child 3919 c036caebfc75
permissions -rw-r--r--
New trivial rewrites
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(*  Title:      HOL/simpdata.ML
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    ID:         $Id$
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    Author:     Tobias Nipkow
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    Copyright   1991  University of Cambridge
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Instantiation of the generic simplifier
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*)
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section "Simplifier";
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open Simplifier;
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(*** Addition of rules to simpsets and clasets simultaneously ***)
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(*Takes UNCONDITIONAL theorems of the form A<->B to 
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        the Safe Intr     rule B==>A and 
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        the Safe Destruct rule A==>B.
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  Also ~A goes to the Safe Elim rule A ==> ?R
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  Failing other cases, A is added as a Safe Intr rule*)
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local
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  val iff_const = HOLogic.eq_const HOLogic.boolT;
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  fun addIff th = 
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      (case HOLogic.dest_Trueprop (#prop(rep_thm th)) of
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                (Const("Not",_) $ A) =>
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                    AddSEs [zero_var_indexes (th RS notE)]
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              | (con $ _ $ _) =>
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                    if con=iff_const
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                    then (AddSIs [zero_var_indexes (th RS iffD2)];  
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                          AddSDs [zero_var_indexes (th RS iffD1)])
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                    else  AddSIs [th]
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              | _ => AddSIs [th];
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       Addsimps [th])
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      handle _ => error ("AddIffs: theorem must be unconditional\n" ^ 
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                         string_of_thm th)
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  fun delIff th = 
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      (case HOLogic.dest_Trueprop (#prop(rep_thm th)) of
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                (Const("Not",_) $ A) =>
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                    Delrules [zero_var_indexes (th RS notE)]
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              | (con $ _ $ _) =>
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                    if con=iff_const
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                    then Delrules [zero_var_indexes (th RS iffD2),
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                                   make_elim (zero_var_indexes (th RS iffD1))]
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                    else Delrules [th]
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              | _ => Delrules [th];
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       Delsimps [th])
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      handle _ => warning("DelIffs: ignoring conditional theorem\n" ^ 
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                          string_of_thm th)
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in
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val AddIffs = seq addIff
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val DelIffs = seq delIff
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end;
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local
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  fun prover s = prove_goal HOL.thy s (fn _ => [blast_tac HOL_cs 1]);
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  val P_imp_P_iff_True = prover "P --> (P = True)" RS mp;
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  val P_imp_P_eq_True = P_imp_P_iff_True RS eq_reflection;
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  val not_P_imp_P_iff_F = prover "~P --> (P = False)" RS mp;
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  val not_P_imp_P_eq_False = not_P_imp_P_iff_F RS eq_reflection;
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  fun atomize pairs =
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    let fun atoms th =
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          (case concl_of th of
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             Const("Trueprop",_) $ p =>
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               (case head_of p of
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                  Const(a,_) =>
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                    (case assoc(pairs,a) of
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                       Some(rls) => flat (map atoms ([th] RL rls))
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                     | None => [th])
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                | _ => [th])
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           | _ => [th])
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    in atoms end;
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  fun gen_all th = forall_elim_vars (#maxidx(rep_thm th)+1) th;
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in
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  fun mk_meta_eq r = r RS eq_reflection;
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  fun mk_meta_eq_simp r = case concl_of r of
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          Const("==",_)$_$_ => r
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      |   _$(Const("op =",_)$lhs$rhs) =>
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             (case fst(Logic.loops (#sign(rep_thm r)) (prems_of r) lhs rhs) of
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                None => mk_meta_eq r
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              | Some _ => r RS P_imp_P_eq_True)
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      |   _$(Const("Not",_)$_) => r RS not_P_imp_P_eq_False
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      |   _ => r RS P_imp_P_eq_True;
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  (* last 2 lines requires all formulae to be of the from Trueprop(.) *)
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val simp_thms = map prover
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 [ "(x=x) = True",
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   "(~True) = False", "(~False) = True", "(~ ~ P) = P",
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   "(~P) ~= P", "P ~= (~P)", "(P ~= Q) = (P = (~Q))",
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   "(True=P) = P", "(P=True) = P",
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   "(True --> P) = P", "(False --> P) = True", 
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   "(P --> True) = True", "(P --> P) = True",
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   "(P --> False) = (~P)", "(P --> ~P) = (~P)",
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   "(P & True) = P", "(True & P) = P", 
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   "(P & False) = False", "(False & P) = False",
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   "(P & P) = P", "(P & (P & Q)) = (P & Q)",
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   "(P & ~P) = False",    "(~P & P) = False",
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   "(P | True) = True", "(True | P) = True", 
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   "(P | False) = P", "(False | P) = P",
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   "(P | P) = P", "(P | (P | Q)) = (P | Q)",
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   "(P | ~P) = True",    "(~P | P) = True",
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   "((~P) = (~Q)) = (P=Q)",
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   "(!x. P) = P", "(? x. P) = P", "? x. x=t", "? x. t=x", 
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   "(? x. x=t & P(x)) = P(t)",
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   "(! x. t=x --> P(x)) = P(t)" ];
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(*Add congruence rules for = (instead of ==) *)
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infix 4 addcongs delcongs;
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fun ss addcongs congs = ss addeqcongs (map standard (congs RL [eq_reflection]));
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fun ss delcongs congs = ss deleqcongs (map standard (congs RL [eq_reflection]));
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fun Addcongs congs = (simpset := !simpset addcongs congs);
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fun Delcongs congs = (simpset := !simpset delcongs congs);
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fun mksimps pairs = map mk_meta_eq_simp o atomize pairs o gen_all;
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val imp_cong = impI RSN
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    (2, prove_goal HOL.thy "(P=P')--> (P'--> (Q=Q'))--> ((P-->Q) = (P'-->Q'))"
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        (fn _=> [blast_tac HOL_cs 1]) RS mp RS mp);
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(*Miniscoping: pushing in existential quantifiers*)
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val ex_simps = map prover 
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                ["(EX x. P x & Q)   = ((EX x. P x) & Q)",
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                 "(EX x. P & Q x)   = (P & (EX x. Q x))",
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                 "(EX x. P x | Q)   = ((EX x. P x) | Q)",
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                 "(EX x. P | Q x)   = (P | (EX x. Q x))",
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                 "(EX x. P x --> Q) = ((ALL x. P x) --> Q)",
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                 "(EX x. P --> Q x) = (P --> (EX x. Q x))"];
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(*Miniscoping: pushing in universal quantifiers*)
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val all_simps = map prover
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                ["(ALL x. P x & Q)   = ((ALL x. P x) & Q)",
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                 "(ALL x. P & Q x)   = (P & (ALL x. Q x))",
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                 "(ALL x. P x | Q)   = ((ALL x. P x) | Q)",
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                 "(ALL x. P | Q x)   = (P | (ALL x. Q x))",
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                 "(ALL x. P x --> Q) = ((EX x. P x) --> Q)",
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                 "(ALL x. P --> Q x) = (P --> (ALL x. Q x))"];
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(*** Simplification procedure for turning  ? x. ... & x = t & ...
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     into                                  ? x. x = t & ... & ...
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     where the latter can be rewritten via (? x. x = t & P(x)) = P(t)
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 ***)
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local
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fun def(eq as (c as Const("op =",_)) $ s $ t) =
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      if s = Bound 0 andalso not(loose_bvar1(t,0)) then Some eq else
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      if t = Bound 0 andalso not(loose_bvar1(s,0)) then Some(c$t$s)
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      else None
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  | def _ = None;
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fun extract(Const("op &",_) $ P $ Q) =
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      (case def P of
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         Some eq => Some(eq,Q)
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       | None => (case def Q of
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                   Some eq => Some(eq,P)
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                 | None =>
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       (case extract P of
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         Some(eq,P') => Some(eq, HOLogic.conj $ P' $ Q)
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       | None => (case extract Q of
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                   Some(eq,Q') => Some(eq,HOLogic.conj $ P $ Q')
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                 | None => None))))
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  | extract _ = None;
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fun prove_eq(ceqt) =
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  let val tac = rtac eq_reflection 1 THEN rtac iffI 1 THEN
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                ALLGOALS(EVERY'[etac exE, REPEAT o (etac conjE),
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                 rtac exI, REPEAT o (ares_tac [conjI] ORELSE' etac sym)])
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  in rule_by_tactic tac (trivial ceqt) end;
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fun rearrange sg _ (F as ex $ Abs(x,T,P)) =
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     (case extract P of
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        None => None
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      | Some(eq,Q) =>
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          let val ceqt = cterm_of sg
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                       (Logic.mk_equals(F,ex $ Abs(x,T,HOLogic.conj$eq$Q)))
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          in Some(prove_eq ceqt) end)
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  | rearrange _ _ _ = None;
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val pattern = read_cterm (sign_of HOL.thy) ("? x. P(x) & Q(x)",HOLogic.boolT)
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in
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val defEX_regroup = mk_simproc "defined EX" [pattern] rearrange;
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end;
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(* elimination of existential quantifiers in assumptions *)
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val ex_all_equiv =
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  let val lemma1 = prove_goal HOL.thy
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        "(? x. P(x) ==> PROP Q) ==> (!!x. P(x) ==> PROP Q)"
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        (fn prems => [resolve_tac prems 1, etac exI 1]);
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      val lemma2 = prove_goalw HOL.thy [Ex_def]
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        "(!!x. P(x) ==> PROP Q) ==> (? x. P(x) ==> PROP Q)"
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        (fn prems => [REPEAT(resolve_tac prems 1)])
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  in equal_intr lemma1 lemma2 end;
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end;
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(* Elimination of True from asumptions: *)
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val True_implies_equals = prove_goal HOL.thy
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 "(True ==> PROP P) == PROP P"
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(fn _ => [rtac equal_intr_rule 1, atac 2,
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          METAHYPS (fn prems => resolve_tac prems 1) 1,
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          rtac TrueI 1]);
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fun prove nm thm  = qed_goal nm HOL.thy thm (fn _ => [blast_tac HOL_cs 1]);
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prove "conj_commute" "(P&Q) = (Q&P)";
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prove "conj_left_commute" "(P&(Q&R)) = (Q&(P&R))";
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val conj_comms = [conj_commute, conj_left_commute];
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prove "conj_assoc" "((P&Q)&R) = (P&(Q&R))";
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prove "disj_commute" "(P|Q) = (Q|P)";
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prove "disj_left_commute" "(P|(Q|R)) = (Q|(P|R))";
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val disj_comms = [disj_commute, disj_left_commute];
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prove "disj_assoc" "((P|Q)|R) = (P|(Q|R))";
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prove "conj_disj_distribL" "(P&(Q|R)) = (P&Q | P&R)";
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prove "conj_disj_distribR" "((P|Q)&R) = (P&R | Q&R)";
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prove "disj_conj_distribL" "(P|(Q&R)) = ((P|Q) & (P|R))";
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prove "disj_conj_distribR" "((P&Q)|R) = ((P|R) & (Q|R))";
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prove "imp_conjR" "(P --> (Q&R)) = ((P-->Q) & (P-->R))";
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prove "imp_conjL" "((P&Q) -->R)  = (P --> (Q --> R))";
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prove "imp_disjL" "((P|Q) --> R) = ((P-->R)&(Q-->R))";
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(*These two are specialized, but imp_disj_not1 is useful in Auth/Yahalom.ML*)
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prove "imp_disj_not1" "((P --> Q | R)) = (~Q --> P --> R)";
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prove "imp_disj_not2" "((P --> Q | R)) = (~R --> P --> Q)";
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prove "imp_disj1" "((P-->Q)|R) = (P--> Q|R)";
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prove "imp_disj2" "(Q|(P-->R)) = (P--> Q|R)";
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prove "de_Morgan_disj" "(~(P | Q)) = (~P & ~Q)";
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prove "de_Morgan_conj" "(~(P & Q)) = (~P | ~Q)";
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prove "not_imp" "(~(P --> Q)) = (P & ~Q)";
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prove "not_iff" "(P~=Q) = (P = (~Q))";
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(*Avoids duplication of subgoals after expand_if, when the true and false 
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  cases boil down to the same thing.*) 
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prove "cases_simp" "((P --> Q) & (~P --> Q)) = Q";
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prove "not_all" "(~ (! x. P(x))) = (? x.~P(x))";
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prove "imp_all" "((! x. P x) --> Q) = (? x. P x --> Q)";
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prove "not_ex"  "(~ (? x. P(x))) = (! x.~P(x))";
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prove "imp_ex" "((? x. P x) --> Q) = (! x. P x --> Q)";
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prove "ex_disj_distrib" "(? x. P(x) | Q(x)) = ((? x. P(x)) | (? x. Q(x)))";
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prove "all_conj_distrib" "(!x. P(x) & Q(x)) = ((! x. P(x)) & (! x. Q(x)))";
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(* '&' congruence rule: not included by default!
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   May slow rewrite proofs down by as much as 50% *)
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let val th = prove_goal HOL.thy 
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                "(P=P')--> (P'--> (Q=Q'))--> ((P&Q) = (P'&Q'))"
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                (fn _=> [blast_tac HOL_cs 1])
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in  bind_thm("conj_cong",standard (impI RSN (2, th RS mp RS mp)))  end;
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let val th = prove_goal HOL.thy 
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                "(Q=Q')--> (Q'--> (P=P'))--> ((P&Q) = (P'&Q'))"
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                (fn _=> [blast_tac HOL_cs 1])
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in  bind_thm("rev_conj_cong",standard (impI RSN (2, th RS mp RS mp)))  end;
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(* '|' congruence rule: not included by default! *)
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let val th = prove_goal HOL.thy 
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                "(P=P')--> (~P'--> (Q=Q'))--> ((P|Q) = (P'|Q'))"
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                (fn _=> [blast_tac HOL_cs 1])
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in  bind_thm("disj_cong",standard (impI RSN (2, th RS mp RS mp)))  end;
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prove "eq_sym_conv" "(x=y) = (y=x)";
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qed_goalw "o_apply" HOL.thy [o_def] "(f o g) x = f (g x)"
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 (fn _ => [rtac refl 1]);
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qed_goal "meta_eq_to_obj_eq" HOL.thy "x==y ==> x=y"
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  (fn [prem] => [rewtac prem, rtac refl 1]);
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qed_goalw "if_True" HOL.thy [if_def] "(if True then x else y) = x"
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 (fn _=>[blast_tac (HOL_cs addIs [select_equality]) 1]);
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qed_goalw "if_False" HOL.thy [if_def] "(if False then x else y) = y"
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 (fn _=>[blast_tac (HOL_cs addIs [select_equality]) 1]);
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qed_goal "if_P" HOL.thy "P ==> (if P then x else y) = x"
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 (fn [prem] => [ stac (prem RS eqTrueI) 1, rtac if_True 1 ]);
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(*
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qed_goal "if_not_P" HOL.thy "~P ==> (if P then x else y) = y"
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 (fn [prem] => [ stac (prem RS not_P_imp_P_iff_F) 1, rtac if_False 1 ]);
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*)
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qed_goalw "if_not_P" HOL.thy [if_def] "!!P. ~P ==> (if P then x else y) = y"
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 (fn _ => [blast_tac (HOL_cs addIs [select_equality]) 1]);
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qed_goal "expand_if" HOL.thy
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    "P(if Q then x else y) = ((Q --> P(x)) & (~Q --> P(y)))"
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 (fn _=> [ (res_inst_tac [("Q","Q")] (excluded_middle RS disjE) 1),
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         stac if_P 2,
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         stac if_not_P 1,
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         REPEAT(blast_tac HOL_cs 1) ]);
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qed_goal "if_bool_eq" HOL.thy
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                   "(if P then Q else R) = ((P-->Q) & (~P-->R))"
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                   (fn _ => [rtac expand_if 1]);
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(** Case splitting **)
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local val mktac = mk_case_split_tac (meta_eq_to_obj_eq RS iffD2)
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in
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fun split_tac splits = mktac (map mk_meta_eq splits)
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end;
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local val mktac = mk_case_split_inside_tac (meta_eq_to_obj_eq RS iffD2)
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in
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fun split_inside_tac splits = mktac (map mk_meta_eq splits)
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end;
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   331
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qed_goal "if_cancel" HOL.thy "(if c then x else x) = x"
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  (fn _ => [split_tac [expand_if] 1, blast_tac HOL_cs 1]);
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(** 'if' congruence rules: neither included by default! *)
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(*Simplifies x assuming c and y assuming ~c*)
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qed_goal "if_cong" HOL.thy
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  "[| b=c; c ==> x=u; ~c ==> y=v |] ==>\
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\  (if b then x else y) = (if c then u else v)"
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  (fn rew::prems =>
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   [stac rew 1, stac expand_if 1, stac expand_if 1,
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    blast_tac (HOL_cs addDs prems) 1]);
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(*Prevents simplification of x and y: much faster*)
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qed_goal "if_weak_cong" HOL.thy
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  "b=c ==> (if b then x else y) = (if c then x else y)"
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  (fn [prem] => [rtac (prem RS arg_cong) 1]);
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(*Prevents simplification of t: much faster*)
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qed_goal "let_weak_cong" HOL.thy
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  "a = b ==> (let x=a in t(x)) = (let x=b in t(x))"
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  (fn [prem] => [rtac (prem RS arg_cong) 1]);
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(*In general it seems wrong to add distributive laws by default: they
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  might cause exponential blow-up.  But imp_disjL has been in for a while
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  and cannot be removed without affecting existing proofs.  Moreover, 
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  rewriting by "(P|Q --> R) = ((P-->R)&(Q-->R))" might be justified on the
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  grounds that it allows simplification of R in the two cases.*)
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val mksimps_pairs =
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  [("op -->", [mp]), ("op &", [conjunct1,conjunct2]),
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   ("All", [spec]), ("True", []), ("False", []),
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   ("If", [if_bool_eq RS iffD1])];
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fun unsafe_solver prems = FIRST'[resolve_tac (TrueI::refl::prems),
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				 atac, etac FalseE];
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(*No premature instantiation of variables during simplification*)
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fun   safe_solver prems = FIRST'[match_tac (TrueI::refl::prems),
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				 eq_assume_tac, ematch_tac [FalseE]];
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val HOL_basic_ss = empty_ss setsubgoaler asm_simp_tac
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			    setSSolver   safe_solver
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			    setSolver  unsafe_solver
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			    setmksimps (mksimps mksimps_pairs);
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val HOL_ss = 
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    HOL_basic_ss addsimps 
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     ([triv_forall_equality, (* prunes params *)
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       True_implies_equals, (* prune asms `True' *)
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       if_True, if_False, if_cancel,
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       o_apply, imp_disjL, conj_assoc, disj_assoc,
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       de_Morgan_conj, de_Morgan_disj, imp_disj1, imp_disj2, not_imp,
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       not_all, not_ex, cases_simp]
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     @ ex_simps @ all_simps @ simp_thms)
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     addsimprocs [defEX_regroup]
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     addcongs [imp_cong];
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   388
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   389
qed_goal "if_distrib" HOL.thy
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  "f(if c then x else y) = (if c then f x else f y)" 
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  (fn _ => [simp_tac (HOL_ss setloop (split_tac [expand_if])) 1]);
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   392
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   393
qed_goalw "o_assoc" HOL.thy [o_def] "f o (g o h) = f o g o h"
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   394
  (fn _ => [rtac ext 1, rtac refl 1]);
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   395
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   396
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   397
val prems = goal HOL.thy "[| P ==> Q(True); ~P ==> Q(False) |] ==> Q(P)";
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   398
by (case_tac "P" 1);
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   399
by (ALLGOALS (asm_simp_tac (HOL_ss addsimps prems)));
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   400
val expand_case = result();
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   401
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   402
fun expand_case_tac P i =
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   403
    res_inst_tac [("P",P)] expand_case i THEN
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   404
    Simp_tac (i+1) THEN 
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   405
    Simp_tac i;
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   406
paulson@2948
   407
paulson@1984
   408
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   409
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   410
(*** Install simpsets and datatypes in theory structure ***)
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   411
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   412
simpset := HOL_ss;
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   413
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   414
exception SS_DATA of simpset;
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   415
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   416
let fun merge [] = SS_DATA empty_ss
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   417
      | merge ss = let val ss = map (fn SS_DATA x => x) ss;
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   418
                   in SS_DATA (foldl merge_ss (hd ss, tl ss)) end;
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   419
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   420
    fun put (SS_DATA ss) = simpset := ss;
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   421
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   422
    fun get () = SS_DATA (!simpset);
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   423
in add_thydata "HOL"
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   424
     ("simpset", ThyMethods {merge = merge, put = put, get = get})
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   425
end;
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   426
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   427
fun simpset_of tname =
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   428
  case get_thydata tname "simpset" of
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   429
      None => empty_ss
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   430
    | Some (SS_DATA ss) => ss;
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   431
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   432
type dtype_info = {case_const:term,
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   433
                   case_rewrites:thm list,
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   434
                   constructors:term list,
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   435
                   induct_tac: string -> int -> tactic,
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   436
                   nchotomy: thm,
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   437
                   exhaustion: thm,
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   438
                   exhaust_tac: string -> int -> tactic,
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   439
                   case_cong:thm};
paulson@1984
   440
paulson@1984
   441
exception DT_DATA of (string * dtype_info) list;
paulson@1984
   442
val datatypes = ref [] : (string * dtype_info) list ref;
paulson@1984
   443
paulson@1984
   444
let fun merge [] = DT_DATA []
paulson@1984
   445
      | merge ds =
paulson@1984
   446
          let val ds = map (fn DT_DATA x => x) ds;
paulson@1984
   447
          in DT_DATA (foldl (gen_union eq_fst) (hd ds, tl ds)) end;
paulson@1984
   448
paulson@1984
   449
    fun put (DT_DATA ds) = datatypes := ds;
paulson@1984
   450
paulson@1984
   451
    fun get () = DT_DATA (!datatypes);
paulson@1984
   452
in add_thydata "HOL"
paulson@1984
   453
     ("datatypes", ThyMethods {merge = merge, put = put, get = get})
paulson@1984
   454
end;
paulson@1984
   455
paulson@1984
   456
oheimb@2636
   457
oheimb@2636
   458
(*** Integration of simplifier with classical reasoner ***)
oheimb@2636
   459
oheimb@2636
   460
(* rot_eq_tac rotates the first equality premise of subgoal i to the front,
oheimb@2636
   461
   fails if there is no equaliy or if an equality is already at the front *)
paulson@3538
   462
local
paulson@3538
   463
  fun is_eq (Const ("Trueprop", _) $ (Const("op ="  ,_) $ _ $ _)) = true
paulson@3538
   464
    | is_eq _ = false;
paulson@3538
   465
  fun find_eq n [] = None
paulson@3538
   466
    | find_eq n (t :: ts) = if (is_eq t) then Some n 
paulson@3538
   467
			    else find_eq (n + 1) ts;
paulson@3538
   468
in
paulson@3538
   469
val rot_eq_tac = 
paulson@3538
   470
     SUBGOAL (fn (Bi,i) => 
paulson@3538
   471
	      case find_eq 0 (Logic.strip_assums_hyp Bi) of
paulson@2805
   472
		  None   => no_tac
paulson@2805
   473
		| Some 0 => no_tac
paulson@3538
   474
		| Some n => rotate_tac n i)
paulson@3538
   475
end;
oheimb@2636
   476
oheimb@2636
   477
(*an unsatisfactory fix for the incomplete asm_full_simp_tac!
oheimb@2636
   478
  better: asm_really_full_simp_tac, a yet to be implemented version of
oheimb@2636
   479
			asm_full_simp_tac that applies all equalities in the
oheimb@2636
   480
			premises to all the premises *)
oheimb@2636
   481
fun safe_asm_more_full_simp_tac ss = TRY o rot_eq_tac THEN' 
oheimb@2636
   482
				     safe_asm_full_simp_tac ss;
oheimb@2636
   483
oheimb@2636
   484
(*Add a simpset to a classical set!*)
oheimb@3206
   485
infix 4 addSss addss;
oheimb@3206
   486
fun cs addSss ss = cs addSaltern (CHANGED o (safe_asm_more_full_simp_tac ss));
oheimb@3206
   487
fun cs addss  ss = cs addbefore                        asm_full_simp_tac ss;
oheimb@2636
   488
oheimb@2636
   489
fun Addss ss = (claset := !claset addss ss);
oheimb@2636
   490
oheimb@2636
   491
(*Designed to be idempotent, except if best_tac instantiates variables
oheimb@2636
   492
  in some of the subgoals*)
oheimb@2636
   493
oheimb@2636
   494
type clasimpset = (claset * simpset);
oheimb@2636
   495
oheimb@2636
   496
val HOL_css = (HOL_cs, HOL_ss);
oheimb@2636
   497
oheimb@2636
   498
fun pair_upd1 f ((a,b),x) = (f(a,x), b);
oheimb@2636
   499
fun pair_upd2 f ((a,b),x) = (a, f(b,x));
oheimb@2636
   500
oheimb@2636
   501
infix 4 addSIs2 addSEs2 addSDs2 addIs2 addEs2 addDs2
oheimb@2636
   502
	addsimps2 delsimps2 addcongs2 delcongs2;
paulson@2748
   503
fun op addSIs2   arg = pair_upd1 (op addSIs) arg;
paulson@2748
   504
fun op addSEs2   arg = pair_upd1 (op addSEs) arg;
paulson@2748
   505
fun op addSDs2   arg = pair_upd1 (op addSDs) arg;
paulson@2748
   506
fun op addIs2    arg = pair_upd1 (op addIs ) arg;
paulson@2748
   507
fun op addEs2    arg = pair_upd1 (op addEs ) arg;
paulson@2748
   508
fun op addDs2    arg = pair_upd1 (op addDs ) arg;
paulson@2748
   509
fun op addsimps2 arg = pair_upd2 (op addsimps) arg;
paulson@2748
   510
fun op delsimps2 arg = pair_upd2 (op delsimps) arg;
paulson@2748
   511
fun op addcongs2 arg = pair_upd2 (op addcongs) arg;
paulson@2748
   512
fun op delcongs2 arg = pair_upd2 (op delcongs) arg;
oheimb@2636
   513
paulson@2805
   514
fun auto_tac (cs,ss) = 
paulson@2805
   515
    let val cs' = cs addss ss 
paulson@2805
   516
    in  EVERY [TRY (safe_tac cs'),
paulson@2805
   517
	       REPEAT (FIRSTGOAL (fast_tac cs')),
oheimb@3206
   518
               TRY (safe_tac (cs addSss ss)),
paulson@2805
   519
	       prune_params_tac] 
paulson@2805
   520
    end;
oheimb@2636
   521
oheimb@2636
   522
fun Auto_tac () = auto_tac (!claset, !simpset);
oheimb@2636
   523
oheimb@2636
   524
fun auto () = by (Auto_tac ());