tuned
authornipkow
Fri, 19 Jun 2009 20:22:28 +0200
changeset 31721 b03270a8c23f
parent 31719 29f5b20e8ee8
child 31722 caa89b41dcf2
tuned
src/HOL/NewNumberTheory/MiscAlgebra.thy
--- a/src/HOL/NewNumberTheory/MiscAlgebra.thy	Fri Jun 19 18:33:10 2009 +0200
+++ b/src/HOL/NewNumberTheory/MiscAlgebra.thy	Fri Jun 19 20:22:28 2009 +0200
@@ -45,12 +45,6 @@
 
 *)
 
-(* This could go in Set.thy *)
-
-lemma UNION_empty: "(UNION F A = {}) = (ALL x: F. (A x) = {})"
-  by auto
-
-
 (* The rest is for the algebra libraries *)
 
 (* This goes in FuncSet.thy. Any reason not to make it a simp rule? *)
@@ -293,11 +287,7 @@
   apply blast
   apply (erule finite_UN_I)
   apply blast
-  apply (subst Int_UN_distrib)
-  apply (subst UNION_empty)
-  apply clarsimp
-  apply (drule_tac x = xa in bspec)back
-  apply (assumption, force)
+  apply (fastsimp)
   apply (auto intro!: funcsetI finprod_closed) 
   apply (subst finprod_insert)
   apply (auto intro!: funcsetI finprod_closed)