(************************************************************************) (* * The Coq Proof Assistant / The Coq Development Team *) (* v * INRIA, CNRS and contributors - Copyright 1999-2018 *) (* y<=x -> x=y]. *) Section TestOrder. Let test : forall x y, x<=y -> y<=x -> x=y. Proof. z_order. Qed. End TestOrder. (** Z forms a ring *) (*Lemma Zring : ring_theory 0 1 NZadd NZmul NZsub Z.opp NZeq. Proof. constructor. exact Zadd_0_l. exact Zadd_comm. exact Zadd_assoc. exact Zmul_1_l. exact Zmul_comm. exact Zmul_assoc. exact Zmul_add_distr_r. intros; now rewrite Zadd_opp_minus. exact Zadd_opp_r. Qed. Add Ring ZR : Zring.*)