| changeset 70628 | 40b63f2655e8 |
| parent 70274 | 7daa65d45462 |
| child 72566 | 831f17da1aab |
--- a/src/HOL/Data_Structures/Tree23_Set.thy Wed Aug 28 23:19:43 2019 +0200 +++ b/src/HOL/Data_Structures/Tree23_Set.thy Thu Aug 29 13:07:56 2019 +0200 @@ -148,7 +148,7 @@ subsubsection "Proofs for isin" lemma isin_set: "sorted(inorder t) \<Longrightarrow> isin t x = (x \<in> set (inorder t))" -by (induction t) (auto simp: isin_simps ball_Un) +by (induction t) (auto simp: isin_simps) subsubsection "Proofs for insert"