src/HOL/Set.ML
changeset 8913 0bc13d5e60b8
parent 8839 31da5b9790c0
child 9041 3730ae0f513a
--- a/src/HOL/Set.ML	Mon May 22 12:28:34 2000 +0200
+++ b/src/HOL/Set.ML	Mon May 22 12:29:02 2000 +0200
@@ -744,7 +744,7 @@
 Goalw [psubset_def] "!!A::'a set. [| A <= B; A ~= B |] ==> A<B";
 by (Blast_tac 1);
 qed "psubsetI";
-AddXIs [psubsetI];
+AddSIs [psubsetI];
 
 Goalw [psubset_def] "A < insert x B ==> (x ~: A) & A<=B | x:A & A-{x}<B";
 by Auto_tac;