data Foo d a = Nil d a
             | Cons a (Foo d a)


--data Vect n a = Cons a (Vect n a)

--data Vect (n::Int) a = Cons a (Vect n a)
--data Vect n a = Cons a (Vect n a)
--              | Nil a

--a = Nil 3

--Is it possible to have a type which accepts two arguments? I was trying to have something like ` data Vect (n::Int) a = Cons a (Vect n a)`