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David Barton writes (edited):
>
> class (Floating a) => Complex a where
> realPart,imagPart :: a -> Float
>
> I have the following as a first cut:
>
>
> instance (RealFloat a) => Complex (CartComp a) where
> realPart (x:!+y) = x
> imagPart (x:!+y) = y
>
> The gurus here will immediately (I trust) recognize that I have typing
> errors in this. The type of Float does not match the general
> RealFloat in the instance definition.
Can't you just explicitly coerce x/y to Float using fromRealFrac?
i.e.,
realPart (x:!+y) = fromRealFrac x
Kevin
