[Haskell] PROPOSAL: class aliases

Wolfgang Jeltsch wolfgang at jeltsch.net
Fri Oct 28 07:25:26 EDT 2005


Am Donnerstag, 27. Oktober 2005 13:18 schrieb Ross Paterson:
> [...]

> extend the class syntax with an annotation on the assumptions (! for now),
> to allow
>
> 	class (Show a, !Additive a, !Negative a, !Multiplicative a) =>
> 			Num a where
> 		fromInteger :: Integer -> a
>
> 		one     = fromInteger 1
> 		zero    = fromInteger 0

I don't think that such a syntax is a good idea, since class contexts are used 
elsewhere where such a syntax doesn't make sense.
 
> [...]

Best wishes,
Wolfgang


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