diff -r 05df64f786a4 -r 74f6817870f9 src/HOL/Library/AssocList.thy
--- a/src/HOL/Library/AssocList.thy	Fri Jan 25 14:54:41 2008 +0100
+++ b/src/HOL/Library/AssocList.thy	Fri Jan 25 14:54:44 2008 +0100
@@ -97,14 +97,6 @@
 lemmas [simp del] = compose_hint
 
 
-subsection {* Lookup *}
-
-lemma lookup_simps [code func]: 
-  "map_of [] k = None"
-  "map_of (p#ps) k = (if fst p = k then Some (snd p) else map_of ps k)"
-  by simp_all
-
-
 subsection {* @{const delete} *}
 
 lemma delete_def: