The Hahn-Banach theorem for real vectorspaces (Isabelle/Isar)
(by Gertrud Bauer, TU Munich);
consts
Ball :: "'a set ë ('a ë bool) ë bool"
syntax
"®Ball" :: "pttrn ë 'a set ë bool ë bool" ("(3Â_Î_./ _)" 10)
translations
"ÂxÎA. P" == "Ball A (³x. P)"
defs
Ball_def "Ball A P Ú Âx. xÎA çè P x"