Proposal: Migrate Data.Functor.{Sum, Product, Compose} from transformers to base.

[M Farkas-Dyck]

On 23/07/2015, Edward Kmett <ekmett at gmail.com> wrote:
> So, as a concrete proposal I propose that we:
>
> 1.) Move Data.Functor.Sum, Data.Functor.Product, Data.Functor.Compose and
> Data.Functor.Classes into base.
>
> 2.) Move Control.Applicative's Const into Data.Functor.Const, but continue
> to re-export it from Control.Applicative.
>
> 3.) Add whatever missing, sensible, instances make sense after the
> transition that were ruled out by these modules' previous placement. *e.g.*
> Data, Generic, Generic1.

+1 all