| changeset 14812 | 4b2c006d0534 |
| parent 14804 | 8de39d3e8eb6 |
| child 14845 | 345934d5bc1a |
--- a/src/HOL/Set.thy Wed May 26 19:06:09 2004 +0200 +++ b/src/HOL/Set.thy Fri May 28 11:19:15 2004 +0200 @@ -1108,6 +1108,9 @@ lemma Collect_disj_eq: "{x. P x | Q x} = {x. P x} \<union> {x. Q x}" by blast +lemma Collect_imp_eq: "{x. P x --> Q x} = -{x. P x} \<union> {x. Q x}" + by blast + lemma Collect_conj_eq: "{x. P x & Q x} = {x. P x} \<inter> {x. Q x}" by blast