proposition: Lemma map_append `(f : a → b) `(xs : t a n) `(ys : t a m) : map f (xs ++ ys) = map f xs ++ map f ys.
proof: Proof. induction xs; simpl; auto. now rewrite IHxs. Qed.
imports: Category.Lib Category.Theory.Category Category.Theory.Isomorphism Category.Theory.Functor Category.Theory.Adjunction Category.Structure.Terminal Category.Structure.Cartesian Category.Structure.BiCCC Category.Instance.Fun Category.Instance.Coq Category.Instance.Sets Coq.Vectors.Vector