[Haskell-cafe] Defining types (newbie)
haskell at brecknell.org
Wed Mar 14 02:43:49 EDT 2007
> But if I want to combine tcEqOne and tcGtThree I run into type
> problems, because one of them uses Strings and the other Integers. I
> want to break the type dependence between the arguments of "And"; can
> I do this?
Try this. You'll also need to change "ThingCompare a" to "ThingCompare"
in all your function type signatures.
> data ThingCompare
> = forall a. TC (BooleanOp a) (Field a)
> | And ThingCompare ThingCompare
> | Or ThingCompare ThingCompare
You might also like to read my post from a few minutes ago:
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