proposition: Fact le_anti : antisymmetric le.
proof: Proof. by move=> x y; rewrite !le_def meetC => /andP [] /eqP {2}<- /eqP ->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)