Set, Map libraries

John Meacham john at
Thu Jun 2 17:11:08 EDT 2005

On Thu, Jun 02, 2005 at 05:03:26PM -0400, S. Alexander Jacobson wrote:
> Any reason the libaries don't define:
>   class HasNull a where null::a->Bool
>   class HasEmpty a where empty::a
> I find that I sometimes switch between using lists, sets, or tables as 
> my collection type and the forced import qualifification for generic 
> collection operations seems annoying.

HasEmpty should be a superclass of Monoid. I have wanted that split out
on various occasions.

John Meacham - ⑆⑆john⑈ 

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