∀ {α : Type u_1} (motive : α ⊕ Computation α → α ⊕ Computation α → Sort u_2) (a a' : α)
  (h_1 : (a a' : α) → motive (Sum.inl a) (Sum.inl a')) (h_2 : (s s' : Computation α) → motive (Sum.inr s) (Sum.inr s'))
  (h_3 : (x x_1 : α ⊕ Computation α) → motive x x_1),
  (match Sum.inl a, Sum.inl a' with
    | Sum.inl a, Sum.inl a' => h_1 a a'
    | Sum.inr s, Sum.inr s' => h_2 s s'
    | x, x_1 => h_3 x x_1) =
    h_1 a a'