fact: Definition PFilterType {T} (F : (T -> Prop) -> Prop) {fF : Filter F} (fN0 : not (F set0)) := PFilterPack F (Build_ProperFilter' fN0 fF).
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed