proposition: Lemma filter_app2 (T : Type) (F : set_system T) : Filter F -> forall P Q R : set T, F (fun x => P x -> Q x -> R x) -> F P -> F Q -> F R.
proof: Proof. by move=> ???? PQR FP; apply: filter_app; apply: filter_app FP. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed