--- a/thys/PDerivs.thy	Wed Sep 18 16:35:57 2019 +0100
+++ b/thys/PDerivs.thy	Sat Oct 24 12:13:39 2020 +0100
@@ -128,7 +128,7 @@
 
 lemma pders_Set_CHAR [simp]:
   shows "pders_Set UNIV1 (CHAR c) = {ONE}"
-unfolding UNIV1_def pders_Set_def 
+unfolding UNIV1_def pders_Set_def
 apply(auto)
 apply(frule rev_subsetD)
 apply(rule pders_CHAR)