--- a/src/HOL/Set.thy Wed Jun 28 16:01:34 2023 +0200+++ b/src/HOL/Set.thy Fri Jun 30 08:17:27 2023 +0200@@ -774,7 +774,7 @@ using that by (auto split: if_splits) qed-lemma insert_UNIV: "insert x UNIV = UNIV"+lemma insert_UNIV[simp]: "insert x UNIV = UNIV" by auto