case nil =>
  simp only [Function.updateListITE]
α β : Type
inst✝ : DecidableEq α
f : α → β
v xs_hd : α
xs_tl : List α
xs_ih : ∀ (ys : List β), v ∉ xs_tl → updateListITE f xs_tl ys v = f v
h1 : v ∉ xs_hd :: xs_tl
⊢ updateListITE f (xs_hd :: xs_tl) [] v = f v
no goals