[Haskell-cafe] Re: a question concerning type constructors

[oleg at pobox.com]

> In Haskell, is it possible to declare a type constructor with a variable
> number of type variables e.g.
>
> data Tuple * ....
>
> allowing the following declarations:
>
> t: Tuple
> u: Tuple Bool
> v: Tuple Bool Int
> w: Tuple Bool Int Char

Although the data constructor such as the `Tuple' is not possible
literally, the declarations like the above can be achieved. Please see
the examples in

	http://www.haskell.org/pipermail/haskell/2006-September/018487.html