diff -r 62fdb4bf7239 -r ec774952190c Myhill_2.thy --- a/Myhill_2.thy Thu Feb 17 21:30:26 2011 +0000 +++ b/Myhill_2.thy Fri Feb 18 12:14:07 2011 +0000 @@ -909,6 +909,7 @@ by (induct r) (auto) +(* section {* Closure properties *} abbreviation @@ -977,6 +978,6 @@ using assms by blast ultimately show "reg (A \ B)" by simp qed - +*) end