Re: [Haskell-beginners] Question: Data Type for user selection

Brent Yorgey wrote:

...

That's a bit of a contradiction, because you are using existentials yourself in your GADT.

No, he isn't.

data BasicSelect a where SelectionNum :: Num a => a -> BasicSelect a SelectionStr :: Show a => a -> BasicSelect a

'a' shows up in the result type of both constructors, so there is no existential quantification going on here.

Oh, right. How would one express this as an ADT? Seems impossible to me. Greets, Ertugrul -- nightmare = unsafePerformIO (getWrongWife >>= sex) http://ertes.de/