--- a/src/Provers/make_elim.ML Sat Dec 31 13:03:55 2005 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,38 +0,0 @@
-(* Title: Provers/make_elim.ML
- ID: $Id$
- Author: Lawrence C Paulson, Cambridge University Computer Laboratory
- Copyright 2000 University of Cambridge
-
-Classical version of Tactic.make_elim
-
-In classical logic, we can make stronger elimination rules using this version.
-For instance, the HOL rule injD is transformed into
- [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
-while Tactic.make_elim would yield the weaker rule
- [| inj ?f; ?f ?x = ?f ?y; ?x = ?y ==> PROP ?W |] ==> PROP ?W
-Such rules can cause Fast_tac to fail and Blast_tac to report "PROOF FAILED"
-*)
-
-signature MAKE_ELIM_DATA =
-sig
- val cla_dist_concl: thm (*"[| ~Z ==> PROP X; PROP Y ==> Z; PROP X ==> PROP Y |] ==> Z"*)
-end;
-
-functor Make_Elim_Fun(Data: MAKE_ELIM_DATA) =
-struct
-
-fun make_elim rl =
- let
- fun compose_extra nsubgoal (tha,i,thb) =
- Seq.list_of (bicompose false (false,tha,nsubgoal) i thb)
- val revcut_rl' = Drule.incr_indexes rl revcut_rl
-
- fun making (i,rl) =
- case compose_extra 2 (Data.cla_dist_concl,i,rl) of
- [] => rl (*terminates by clash of variables!*)
- | rl'::_ => making (i+1,rl')
- in making (2, hd (compose_extra 1 (rl, 1, revcut_rl'))) end
- handle (*in default, use the previous version, which never fails*)
- THM _ => Tactic.make_elim rl | Empty => Tactic.make_elim rl;
-
-end;