From: Enrico Tassi <enrico.tassi@inria.fr>
Date: Thu, 6 Jul 2006 09:04:36 +0000 (+0000)
Subject: eq_f1
X-Git-Tag: 0.4.95@7852~1239
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=6d32e0d926eabf01e941290399b8d6b0b812ecfa;p=helm.git

eq_f1
---

diff --git a/matita/library/logic/equality.ma b/matita/library/logic/equality.ma
index b87dc6c95..0675edc76 100644
--- a/matita/library/logic/equality.ma
+++ b/matita/library/logic/equality.ma
@@ -72,6 +72,11 @@ theorem eq_f: \forall  A,B:Type.\forall f:A\to B.
 intros.elim H.reflexivity.
 qed.
 
+theorem eq_f1: \forall  A,B:Type.\forall f:A\to B.
+\forall x,y:A. x=y \to f y = f x.
+intros.elim H.reflexivity.
+qed.
+
 theorem eq_f2: \forall  A,B,C:Type.\forall f:A\to B \to C.
 \forall x1,x2:A. \forall y1,y2:B.
 x1=x2 \to y1=y2 \to f x1 y1 = f x2 y2.