2014: Pointed (was: 2014 Applicative => Monad proposal)

On 05/24/2013 04:28 PM, Roman Cheplyaka wrote:

I completely agree with Edward here.

* Edward Kmett [2013-05-24 11:20:51-0400]

...

For the record I'm actually -1 on including Pointed.

My experience is that there are very few uses for the class that permit you to reason about your code without one-off ad hoc reasoning based on the particular instance you are given. Now, the Apply and Bind classes on the other hand... =) Though, to be fair, I couldn't seriously propose including either of those, either. Even I can't be bothered to instantiate them all the time!

-Edward So maybe we should turn this around and ask those who were +1 on this specific item - why do you want Pointed?

For me, I've occasionally wanted a uniform interface to things like "Set.singleton", with the ability to switch that to lists because sometimes that makes things easier to play with in GHCi. Arguably a weak point, but that is what's tempted me with it before. What are the other problems that Pointed solves? - ocharles