proposition: Lemma meetKI y x : join x (meet x y) = x.
proof: Proof. by rewrite /join /meet f'_can meetKU f_can. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)