End intRing.
End intRing.
Canonical int_Ring := Eval hnf in RingType int intRing.comMixin.
Canonical int_comRing := Eval hnf in ComRingType int intRing.mulzC.
Section intRingTheory.
Implicit Types m n : int.
Local Coercion Posz : nat >-> int.

Lemma intS (n : nat) : n.+1%:Z = 1 + n%:Z. Proof. by rewrite -PoszD. Qed.