changeset 18447 | da548623916a |
parent 18372 | 2bffdf62fe7f |
child 18576 | 8d98b7711e47 |
--- a/src/HOL/Unix/Unix.thy Tue Dec 20 22:06:00 2005 +0100 +++ b/src/HOL/Unix/Unix.thy Wed Dec 21 12:02:57 2005 +0100 @@ -1058,7 +1058,8 @@ have "lookup root ((path @ [y]) @ (us @ [u])) \<noteq> None \<or> lookup root ((path @ [y]) @ us) \<noteq> None" by cases (auto dest: access_some_lookup) - then show ?thesis by (blast dest!: lookup_some_append) + then show ?thesis + by (simp add: not_None_eq, blast dest!: lookup_some_append) qed finally show ?thesis . qed