Having Applicative might be nice for `pure`. That way we can getSum . foldMap pure, and so on. Of course, in that case using `Sum` is no different, but this opens up the ability to construct `Sum`s from other parts of code that simply require `Applicative`.

On Sat, Feb 21, 2015 at 7:57 PM, Sean Leather <sean.leather@gmail.com> wrote:

On Sat, Feb 21, 2015 at 8:51 PM, Oleg Grenrus wrote:
Sean, is there a trac ticket for this issue? I could make a patch early next week, as this seems to be discussed previously.

No, please create one. Also, you could put a patch on Phab and share both links here.

On Sat, Feb 21, 2015 at 9:44 PM, Joachim Breitner wrote:
It’s Applicative and Monad that I’m unsure about.

Good point. I'm also unsure. Do we need/want Applicative, Monad, and MonadFix instances that are analogues of Identity? Has anyone ever needed a Sum/Product/First/Last monad?

Regards,
Sean

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