(* Title: HOL/cladata.ML
ID: $Id$
Author: Tobias Nipkow
Copyright 1996 University of Cambridge
Setting up the classical reasoner.
*)
(** Applying HypsubstFun to generate hyp_subst_tac **)
section "Classical Reasoner";
structure Hypsubst_Data =
struct
structure Simplifier = Simplifier
(*Take apart an equality judgement; otherwise raise Match!*)
fun dest_eq (Const("op =",T) $ t $ u) = (t, u, domain_type T)
val dest_Trueprop = HOLogic.dest_Trueprop
val dest_imp = HOLogic.dest_imp
val eq_reflection = eq_reflection
val rev_eq_reflection = def_imp_eq
val imp_intr = impI
val rev_mp = rev_mp
val subst = subst
val sym = sym
val thin_refl = prove_goal (the_context ())
"!!X. [|x=x; PROP W|] ==> PROP W" (K [atac 1]);
end;
structure Hypsubst = HypsubstFun(Hypsubst_Data);
open Hypsubst;
(*prevent substitution on bool*)
fun hyp_subst_tac' i thm = if i <= Thm.nprems_of thm andalso
Term.exists_Const (fn ("op =", Type (_, [T, _])) => T <> Type ("bool", []) | _ => false)
(List.nth (Thm.prems_of thm, i - 1)) then hyp_subst_tac i thm else no_tac thm;
(*** Applying ClassicalFun to create a classical prover ***)
structure Classical_Data =
struct
val mp = mp
val not_elim = notE
val classical = classical
val sizef = size_of_thm
val hyp_subst_tacs=[hyp_subst_tac]
end;
structure Classical = ClassicalFun(Classical_Data);
structure BasicClassical: BASIC_CLASSICAL = Classical;
open BasicClassical;
val _ = bind_thm ("contrapos_np", inst "Pa" "?Q" Classical.swap);
(*Propositional rules*)
val prop_cs = empty_cs addSIs [refl,TrueI,conjI,disjCI,impI,notI,iffI]
addSEs [conjE,disjE,impCE,FalseE,iffCE];
(*Quantifier rules*)
val HOL_cs = prop_cs addSIs [allI,ex_ex1I] addIs [exI, the_equality]
addSEs [exE] addEs [allE];
val clasetup = (fn thy => (change_claset_of thy (fn _ => HOL_cs); thy));