Definition t := ascii.Definition eq := @eq ascii.Definition eq_refl := @eq_refl t.Definition eq_sym := @eq_sym t.Definition eq_trans := @eq_trans t.Definition cmp : ascii -> ascii -> comparison := Ascii.compare.

(* Specifications: *)
Lemma cmp_eq (a b : ascii): cmp a b = Eq <-> a = b.
Lemma cmp_lt_nat (a b : ascii): cmp a b = Lt <-> (nat_of_ascii a < nat_of_ascii b)%nat.
Lemma cmp_antisym (a b : ascii): cmp a b = CompOpp (cmp b a).