proposition: Lemma eq_near {T} {F : set_system T} (P Q : set T) : (forall x, P x <-> Q x) -> (\forall x \near F, P x) = (\forall x \near F, Q x).
proof: Proof. by move=> /predeqP ->. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed