src/HOL/Complete_Lattice.thy
changeset 44815 b1b436f75070
parent 44814 e6928fc2332a
child 44838 610efb6bda1f
equal deleted inserted replaced
44814:e6928fc2332a 44815:b1b436f75070
   939   by (fact SUP_constant)
   939   by (fact SUP_constant)
   940 
   940 
   941 lemma UN_eq: "(\<Union>x\<in>A. B x) = \<Union>({Y. \<exists>x\<in>A. Y = B x})"
   941 lemma UN_eq: "(\<Union>x\<in>A. B x) = \<Union>({Y. \<exists>x\<in>A. Y = B x})"
   942   by (fact SUP_eq)
   942   by (fact SUP_eq)
   943 
   943 
   944 lemma image_Union: "f ` \<Union>S = (\<Union>x\<in>S. f ` x)" -- "FIXME generalize"
   944 lemma image_Union: "f ` \<Union>S = (\<Union>x\<in>S. f ` x)"
   945   by blast
   945   by blast
   946 
   946 
   947 lemma UNION_empty_conv[simp]:
   947 lemma UNION_empty_conv[simp]:
   948   "{} = (\<Union>x\<in>A. B x) \<longleftrightarrow> (\<forall>x\<in>A. B x = {})"
   948   "{} = (\<Union>x\<in>A. B x) \<longleftrightarrow> (\<forall>x\<in>A. B x = {})"
   949   "(\<Union>x\<in>A. B x) = {} \<longleftrightarrow> (\<forall>x\<in>A. B x = {})"
   949   "(\<Union>x\<in>A. B x) = {} \<longleftrightarrow> (\<forall>x\<in>A. B x = {})"