src/HOL/Data_Structures/Sorting.thy

--- a/src/HOL/Data_Structures/Sorting.thy	Fri Sep 07 20:15:17 2018 +0200
+++ b/src/HOL/Data_Structures/Sorting.thy	Fri Sep 07 21:30:55 2018 +0200
@@ -44,7 +44,7 @@
 apply(auto simp add: set_insort)
 done
 
-lemma "sorted (isort xs)"
+lemma sorted_isort: "sorted (isort xs)"
 apply(induction xs)
 apply(auto simp: sorted_insort)
 done