proposition: Lemma sameclass_equiv : forall `{WF} x y, (fst (equiv t x y) = true <-> sameclass t x y).
proof: Proof. intros t Hwf x y. unfold equiv. repeat (case find_spec; intros; auto). unfold sameclass; rewrite ?Heq, ?Heq0 in *. num_analyse; simpl; subst. intuition. clear H. exists rx0; eauto. intuition try discriminate. elim n. destruct H. transitivity x0; eauto using repr_inj_right. Qed.
imports: ATBR(Common) ATBR(MyFSets) ATBR(BoolView) ATBR(Numbers)