--- a/progs/Matcher.thy	Mon Feb 03 13:25:59 2025 +0000
+++ b/progs/Matcher.thy	Fri Sep 05 16:59:48 2025 +0100
@@ -107,6 +107,8 @@
 apply(simp only: L.simps)
 apply(simp)
 (* SEQ case *)
+apply(simp only: L.simps)
+apply(simp)
 oops
 
 lemma nullable_correctness: