induction l.
- reflexivity.
- simpl; apply f_equal;apply IHl.
Qed.

(* Specifications: *)
Lemma Lget_map : forall (A B:Set) (f:A -> B) i l,
Lget i (List.map  f l) =
match Lget i l with Some a =>
Some (f a) | None => None end.