--- a/thys3/LexerSimp.thy Wed Feb 15 11:52:22 2023 +0000
+++ b/thys3/LexerSimp.thy Thu Feb 16 23:23:22 2023 +0000
@@ -2,7 +2,7 @@
imports "Lexer"
begin
-section {* Lexer including some simplifications *}
+section \<open>Lexer including some simplifications\<close>
fun F_RIGHT where