src/HOL/Analysis/Topology_Euclidean_Space.thy
changeset 69313 b021008c5397
parent 69286 e4d5a07fecb6
child 69325 4b6ddc5989fc
--- a/src/HOL/Analysis/Topology_Euclidean_Space.thy	Sun Nov 18 09:51:41 2018 +0100
+++ b/src/HOL/Analysis/Topology_Euclidean_Space.thy	Sun Nov 18 18:07:51 2018 +0000
@@ -440,8 +440,8 @@
         show ?case by (intro exI[of _ "{{}}"]) simp
       next
         case (Int a b)
-        then obtain x y where x: "a = UNION x Inter" "\<And>i. i \<in> x \<Longrightarrow> finite i \<and> i \<subseteq> B"
-          and y: "b = UNION y Inter" "\<And>i. i \<in> y \<Longrightarrow> finite i \<and> i \<subseteq> B"
+        then obtain x y where x: "a = \<Union>(Inter ` x)" "\<And>i. i \<in> x \<Longrightarrow> finite i \<and> i \<subseteq> B"
+          and y: "b = \<Union>(Inter ` y)" "\<And>i. i \<in> y \<Longrightarrow> finite i \<and> i \<subseteq> B"
           by blast
         show ?case
           unfolding x y Int_UN_distrib2
@@ -450,10 +450,10 @@
         case (UN K)
         then have "\<forall>k\<in>K. \<exists>B'\<subseteq>{b. finite b \<and> b \<subseteq> B}. UNION B' Inter = k" by auto
         then obtain k where
-            "\<forall>ka\<in>K. k ka \<subseteq> {b. finite b \<and> b \<subseteq> B} \<and> UNION (k ka) Inter = ka"
+            "\<forall>ka\<in>K. k ka \<subseteq> {b. finite b \<and> b \<subseteq> B} \<and> \<Union>(Inter ` (k ka)) = ka"
           unfolding bchoice_iff ..
         then show "\<exists>B'\<subseteq>{b. finite b \<and> b \<subseteq> B}. UNION B' Inter = \<Union>K"
-          by (intro exI[of _ "UNION K k"]) auto
+          by (intro exI[of _ "\<Union>(k ` K)"]) auto
       next
         case (Basis S)
         then show ?case