proposition: Lemma lte_dsubl_addr x y z : y \is a fin_num -> (x - y < z) = (x < z + y).
proof: Proof. by move=> ?; rewrite !dual_addeE lteNl lteNr oppeK lte_subl_addr. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra) signed