proposition: Lemma eq_maxl x y : (max x y == x) = (y <= x).
proof: Proof. exact: comparable_eq_maxl. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)