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