proposition: Lemma dsubre_gt0 x y : y \is a fin_num -> (0 < y - x) = (x < y).
proof: Proof. by move=> ?; rewrite lte_dsuber_addl// dadde0. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra) signed