proposition: Fact le_def x y : x <= y = (meet x y == x).
proof: Proof. by rewrite meetE (eq_meetl x y). Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)