[Haskell-cafe] Adding Ord constraint to instance Monad Set?
wolfgang at jeltsch.net
Wed Mar 31 14:09:49 EST 2004
Am Mittwoch, 31. März 2004 13:51 schrieb Henning Thielemann:
> > A data type declaration creates two things - the data type itself
> > and the constructor function.
> > If you consider the constrains in the data type declaration to
> > apply only to the constructor then it all makes sense.
> If this is the meaning then in my opinion the syntax is misleading and it
> should be instead like
> data Either a b =
> (Ord a) => Left a
> | (Num b) => Right b
> (just a fictive example)
This syntax would also have the advantage that you can apply different
contexts to different constructors.
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