Matthew Sackman wrote:
> > class G a where
> > data E a :: *
> > wrap :: a -> E a
> > unwrap :: E a -> a
>
> I'm afraid not. I really need wrap to take a 'b' and unwrap to return a 'b'.
> Talking on #haskell to sjanssen last night, he came up with:
How does
class F a where
data B a :: *
data E a :: *
wrap :: B a -> E a
unwrap :: E a -> B a
sound? 'B a' would represent the 'b' in your previous attempt,
class F a b | a -> b where
...
Bertram
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