John Meacham john at
Thu Oct 27 01:47:24 EDT 2005

On Wed, Oct 26, 2005 at 09:55:07PM -0700, Ashley Yakeley wrote:
> OK, so the last one's silly. But maybe Monoid should be a datatype 
> rather than a class?

no reason we can't have both. I certainly would not want to see the
Monoid class go away, it is perhaps one of the most useful
abstractions... I would like to see it split up like

class HasEmpty a where
        mempty :: a

class HasEmpty a => Monoid a where
        mappend :: a -> a -> a
        mconcat :: [a] -> a


perhaps if my class alias proposal takes off....


John Meacham - ⑆⑆john⑈ 

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