changeset 4003 | 2bbeed529077 |
parent 3919 | c036caebfc75 |
child 4059 | 59c1422c9da5 |
--- a/src/HOL/equalities.ML Fri Oct 24 18:02:23 1997 +0200 +++ b/src/HOL/equalities.ML Fri Oct 24 18:10:51 1997 +0200 @@ -336,6 +336,11 @@ by (Blast_tac 1); qed "Union_Int_subset"; +goal Set.thy "(Union M = {}) = (! A : M. A = {})"; +by (blast_tac (!claset addEs [equalityE]) 1); +qed"Union_empty_conv"; +AddIffs [Union_empty_conv]; + val prems = goal Set.thy "(Union(C) Int A = {}) = (! B:C. B Int A = {})"; by (blast_tac (!claset addSEs [equalityE]) 1);