proposition: Lemma ltW x y : x < y -> x <= y.
proof: Proof. by rewrite lt_def => /andP[]. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)