[Haskell-cafe] MonadPlus or Alternative or ...?

Edward Kmett ekmett at gmail.com
Mon May 3 10:09:15 EDT 2010


On Sat, May 1, 2010 at 7:11 PM, Sean Leather <leather at cs.uu.nl> wrote:

> I want to generalize a set of functions from lists to some functor type. I
> require the following three operation types.
>
>   f a
>   a -> f a
>   f a -> f a -> f a
>

Since f is a functor, FunctorPlus and Pointed together get you exactly the
subset of functionality that you want. Whether or not category-extras can be
considered a light weight dependency on the other hand is another thing
entirely. ;)

-Edward Kmett
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