foo : Π (A : Type) [H : inhabited A], A → A foo' : Π {A : Type} [H : inhabited A] {x : A}, A foo ℕ 10 : ℕ definition test : ∀ {A : Type} [H : inhabited A], @foo' ℕ nat.is_inhabited (@has_add.add ℕ nat_has_add 5 5) = 10 := λ (A : Type) (H : inhabited A), @rfl ℕ (@foo' ℕ nat.is_inhabited (@has_add.add ℕ nat_has_add 5 5))