diff options
author | Samuel Mimram <samuel.mimram@ens-lyon.org> | 2004-07-28 21:54:47 +0000 |
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committer | Samuel Mimram <samuel.mimram@ens-lyon.org> | 2004-07-28 21:54:47 +0000 |
commit | 6b649aba925b6f7462da07599fe67ebb12a3460e (patch) | |
tree | 43656bcaa51164548f3fa14e5b10de5ef1088574 /theories7/Bool/DecBool.v |
Imported Upstream version 8.0pl1upstream/8.0pl1
Diffstat (limited to 'theories7/Bool/DecBool.v')
-rwxr-xr-x | theories7/Bool/DecBool.v | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/theories7/Bool/DecBool.v b/theories7/Bool/DecBool.v new file mode 100755 index 00000000..c22cd032 --- /dev/null +++ b/theories7/Bool/DecBool.v @@ -0,0 +1,27 @@ +(************************************************************************) +(* v * The Coq Proof Assistant / The Coq Development Team *) +(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(************************************************************************) + +(*i $Id: DecBool.v,v 1.1.2.1 2004/07/16 19:31:25 herbelin Exp $ i*) + +Set Implicit Arguments. + +Definition ifdec : (A,B:Prop)(C:Set)({A}+{B})->C->C->C + := [A,B,C,H,x,y]if H then [_]x else [_]y. + + +Theorem ifdec_left : (A,B:Prop)(C:Set)(H:{A}+{B})~B->(x,y:C)(ifdec H x y)=x. +Intros; Case H; Auto. +Intro; Absurd B; Trivial. +Qed. + +Theorem ifdec_right : (A,B:Prop)(C:Set)(H:{A}+{B})~A->(x,y:C)(ifdec H x y)=y. +Intros; Case H; Auto. +Intro; Absurd A; Trivial. +Qed. + +Unset Implicit Arguments. |