>But if you dislike tuples you can use nested pairs, like
>
> infixr 0 :.
> data T a b = a :. b
>
>Now you can write
>
> 'a' :. True :. "Hello" :. ()
>
>which has type
>
> T Char (T Bool (T String ()))
>
>But I guess that's not what you were after?
>
> -- Lennart
Fergus replied:
> > [...] if you dislike tuples you can use nested pairs
>
> At the cost of losing a little type-safety.
Well, since no one else mentions it: It's fun to (try to) define some
functions over these ``heterogeneous lists''.
In which languages can you define, e.g., a length function?-)
Claus
PS. I've got a length function for ``heterogeneous lists'', as
they appear in nested pairs, in Hugs. However, it uses the
type system extensions available in 1.3c or in 1.4 [981111 BETA].
How much can you do in plain Haskell??? in Cayenne?-)
