src/HOL/Multivariate_Analysis/Topology_Euclidean_Space.thy
changeset 56742 678a52e676b6
parent 56544 b60d5d119489
child 57275 0ddb5b755cdc
equal deleted inserted replaced
56741:2b3710a4fa94 56742:678a52e676b6
  3289 lemma eventually_filter_from_subbaseI: "P \<in> B \<Longrightarrow> eventually P (filter_from_subbase B)"
  3289 lemma eventually_filter_from_subbaseI: "P \<in> B \<Longrightarrow> eventually P (filter_from_subbase B)"
  3290   by (subst eventually_filter_from_subbase) (auto intro!: exI[of _ "{P}"])
  3290   by (subst eventually_filter_from_subbase) (auto intro!: exI[of _ "{P}"])
  3291 
  3291 
  3292 lemma filter_from_subbase_not_bot:
  3292 lemma filter_from_subbase_not_bot:
  3293   "\<forall>X \<subseteq> B. finite X \<longrightarrow> Inf X \<noteq> bot \<Longrightarrow> filter_from_subbase B \<noteq> bot"
  3293   "\<forall>X \<subseteq> B. finite X \<longrightarrow> Inf X \<noteq> bot \<Longrightarrow> filter_from_subbase B \<noteq> bot"
  3294   unfolding trivial_limit_def eventually_filter_from_subbase by auto
  3294   unfolding trivial_limit_def eventually_filter_from_subbase
       
  3295     bot_bool_def [symmetric] bot_fun_def [symmetric] bot_unique by simp
  3295 
  3296 
  3296 lemma closure_iff_nhds_not_empty:
  3297 lemma closure_iff_nhds_not_empty:
  3297   "x \<in> closure X \<longleftrightarrow> (\<forall>A. \<forall>S\<subseteq>A. open S \<longrightarrow> x \<in> S \<longrightarrow> X \<inter> A \<noteq> {})"
  3298   "x \<in> closure X \<longleftrightarrow> (\<forall>A. \<forall>S\<subseteq>A. open S \<longrightarrow> x \<in> S \<longrightarrow> X \<inter> A \<noteq> {})"
  3298 proof safe
  3299 proof safe
  3299   assume x: "x \<in> closure X"
  3300   assume x: "x \<in> closure X"