λ {A} B a b, a : Π B, ?A → B → ?A
λ {A B} a b, a : ?A → ?B → ?A
λ A {B} a b, a : Π A {B}, A → B → A
λ A B a b, a : Π A B, A → B → A
λ [A] B a b, a : Π B, ?A → B → ?A
λ ⦃A⦄ {B} a b, a : Π ⦃A⦄ {B}, A → B → A
λ ⦃A B⦄ a b, a : Π ⦃A B⦄, A → B → A