Proposal: Add a wrapped applicative type to Data.Monoid

[Daniel Cartwright]

One thing that I would like to respectfully point out - is that the
members' of this library mailing list end up derailing otherwise useful
conversations over the choice of a name, which is frankly a silly
bottleneck. I would much rather roll a die or flip a coin to choose a name,
and just get on to implementing the proposed thing, provided it is the case
that it is seen as generally useful.

On Tue, Mar 27, 2018 at 10:59 AM, Daniel Cartwright <chessai1996 at gmail.com>
wrote:

> I can definitely see "App" as being overloaded (Application).
> Good names that I see are "Ap" and "Apply".
>
> I think "Ap" is fine.
> On Tue, Mar 27, 2018, 10:28 AM David Feuer <david.feuer at gmail.com> wrote:
>
>> I proposed same thing some time ago. The main point of contention was the
>> name. I hope you have better luck!
>>
>> On Tue, Mar 27, 2018, 10:23 AM Daniel Cartwright <chessai1996 at gmail.com>
>> wrote:
>>
>>> I see this as being generally (as in, to the users of Haskell as a
>>> whole) useful:
>>>
>>> newtype Ap f a = Ap { getAp :: f a }
>>>   deriving (Applicative, Eq, Foldable, Functor, Generic, Generic1
>>>                 ,Monad, Ord, Read, Show, Traversable)
>>>
>>> Some hand-written instances:
>>> instance (Applicative f, Semigroup a) => Semigroup (Ap f a) where
>>>   (Ap x) <> (Ap y) = Ap $ liftA2 (<>) x y
>>>
>>> instance (Applicative f, Monoid a) => Monoid (Ap f a) where
>>>   mempty = Ap $ pure mempty
>>> _______________________________________________
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>>>
>>
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