diff -r 6ce0c8d59f5a -r ec121999a9cb src/ZF/Trancl.thy
--- a/src/ZF/Trancl.thy	Sun Oct 06 22:56:07 2024 +0200
+++ b/src/ZF/Trancl.thy	Tue Oct 08 12:10:35 2024 +0200
@@ -32,7 +32,7 @@
     "trans(r) \<equiv> \<forall>x y z. \<langle>x,y\<rangle>: r \<longrightarrow> \<langle>y,z\<rangle>: r \<longrightarrow> \<langle>x,z\<rangle>: r"
 
 definition
-  trans_on :: "[i,i]\<Rightarrow>o"  (\<open>trans[_]'(_')\<close>)  where
+  trans_on :: "[i,i]\<Rightarrow>o"  (\<open>(\<open>open_block notation=\<open>mixfix trans_on\<close>\<close>trans[_]'(_'))\<close>)  where
     "trans[A](r) \<equiv> \<forall>x\<in>A. \<forall>y\<in>A. \<forall>z\<in>A.
                           \<langle>x,y\<rangle>: r \<longrightarrow> \<langle>y,z\<rangle>: r \<longrightarrow> \<langle>x,z\<rangle>: r"