Marcin 'Qrczak' Kowalczyk writes:
> Thu, 3 Feb 2000 14:24:28 +1300 (NZD), Tom Pledger <[EMAIL PROTECTED]> pisze:
>
> > instance (Bounded a, Enum a) => Random a where ...
>
> > But, every type in (Bounded, Enum) has a potential instance of Random,
> > using no properties of the type except its Bounded and Enum functions.
>
> Potential. But this does not need to be *the* implementation for
> all types (e.g. Doubles).
I hope that Double isn't Bounded. Double was meant to be one of the
"other things" in the opening remark:
"Everything which is both an X and a Y is also a Z, and some other
things are Zs too."
> So you want overlapping instances, with some rules of disambiguation?
> They cause troubles.
>
> [discussion of overlapping instances]
> [default implementation as external functions]
How about the cases which do not involve overlapping instances?
Regards,
Tom
