asum really needs to go into the Foldable class (or something)

[David Feuer]

OK, so can you suggest a good implementation of sum or asum or traverse_
that will work sanely regardless of the monoid? Because I can't think of
any way to do that. Or can you think of a better way than FoldableMP to
accomplish that objective?
On Nov 5, 2014 1:45 PM, "Edward Kmett" <ekmett at gmail.com> wrote:

> Please consider me strongly against such a FoldableMP class.
>
> -Edward
>
> On Wed, Nov 5, 2014 at 11:42 AM, David Feuer <david.feuer at gmail.com>
> wrote:
>
>> The current definition is "biased", using foldr and <|> instead of
>> foldMap and the new Alt. This is a bit awkward in the post-BBP world, but
>> we also don't want to just debias it across the board, because if the
>> Foldable is holding lists, the debiased version will be very bad.
>>
>> More generally, there are a number of Foldable members that are very
>> awkward, pleading for MPTC, because the sane implementations depend on both
>> the container type and the element type. I know we're pushing right up
>> against the deadline for 7.10.1, but the current situation is making me
>> very nervous.
>>
>> David
>>
>
>
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