proposition: Lemma meetx0 : right_zero \bot (@meet _ L).
proof: Proof. by move=> x; rewrite meetC meet0x. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)