proposition: Lemma disj_leC x y : (x `&` y == \bot) = (x <= ~` y).
proof: Proof. by rewrite -diff_eq0 diffE complK. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)