proposition: Lemma inj_v_inj : injective inj_v.
proof: Proof. move => x y. by move/ord_inj/enum_rank_inj. Qed.
imports: Coq(Relation_Definitions Morphisms RelationClasses) mathcomp(all_ssreflect) GraphTheory(edone finite_quotient preliminaries bij equiv) GraphTheory(setoid_bigop structures pttdom mgraph mgraph2) GraphTheory(rewriting open_confluence finmap_plus)