diff -r ce09935439b3 -r 2e0b7ca391dc src/Tools/isac/Knowledge/Inverse_Z_Transform.thy
--- a/src/Tools/isac/Knowledge/Inverse_Z_Transform.thy	Wed Aug 03 18:17:27 2022 +0200
+++ b/src/Tools/isac/Knowledge/Inverse_Z_Transform.thy	Thu Aug 04 12:48:37 2022 +0200
@@ -27,7 +27,7 @@
 
 ML \<open>
 val inverse_z = prep_rls'(
-  Rule_Def.Repeat {id = "inverse_z", preconds = [], rew_ord = ("dummy_ord",Rewrite_Ord.dummy_ord), 
+  Rule_Def.Repeat {id = "inverse_z", preconds = [], rew_ord = ("dummy_ord",Rewrite_Ord.function_empty), 
 	  erls = Rule_Set.Empty, srls = Rule_Set.Empty, calc = [], errpatts = [],
 	  rules = 
 	   [