(* Canonical comparison and eqType for nat.                                *)

Fixpoint eqn m n {struct m} :=
  match m, n with
  | 0, 0 => true
  | m'.+1, n'.+1 => eqn m' n'
  | _, _ => false
  end.

(* Specifications: *)
Lemma eqnP : Equality.axiom eqn.