proposition: Lemma guarded_bij_empty_empty: forall vmap emap (G: PreGraph V E) (G': PreGraph V' E'), guarded_bij (Empty_set V) (Empty_set E) vmap emap G G'.
proof: Proof. intros. split; [.. | split]. + apply is_guarded_inj_empty. + apply is_guarded_inj_empty. + intros. inversion H. + intros. inversion H. + intros. inversion H. + intros. inversion H. Qed.
imports: CertiGraph.lib.Coqlib CertiGraph.lib.Ensembles_ext CertiGraph.lib.EquivDec_ext CertiGraph.lib.relation_list CertiGraph.lib.Morphisms_ext CertiGraph.lib.List_ext CertiGraph.graph.graph_model CertiGraph.graph.path_lemmas CertiGraph.graph.reachable_ind CertiGraph.graph.subgraph2 CertiGraph.graph.graph_gen CertiGraph.graph.graph_relation