proposition: Lemma cvg_fst {T U F G} {FG : Filter G} : (@fst T U) @ filter_prod F G --> F.
proof: Proof. by move=> P; apply: filter_prod1. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed