case cons a as h_ind =>
  constructor
  case left => exact List.forAll_of_forAll (himp a) ha
  case right => exact h_ind has
α : Type u_1
β : Type u_2
r r₁ : α → β → Prop
himp : ∀ (a : α) (b : β), r a b → r₁ a b
a : α
as : List α
h_ind : ∀ {bs : List β}, List.forAllRel r as bs → List.forAllRel r₁ as bs
bs : List β
ha : forAll (r a) bs
has : List.forAllRel r as bs
⊢ forAll (r₁ a) bs ∧ List.forAllRel r₁ as bs
no goals