Section Ops.
Variables (K : ordType) (V : Type).
Notation fmap := (finMap K V).
Notation key := (@key K V).
Notation value := (@value K V).
Notation predk := (@predk K V).
Notation predCk := (@predCk K V).

Lemma sorted_nil : sorted ord (map key [::]). Proof. by []. Qed.