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

Edward Kmett ekmett at gmail.com
Wed Nov 5 18:45:34 UTC 2014


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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