induction as with
| nil => rfl
| cons a as hi =>
  rw [cons_bind, cons_bind]
  rw [append_bind]
  rw [hi]
α β : Type u
γ : Type w
as : List α
f : α → List β
g : β → List γ
⊢ List.bind (List.bind as f) g = List.bind as fun x => List.bind (f x) g
no goals