Whither split base?

Tue Oct 30 14:05:51 UTC 2018

The typeable API in Type.* might be able to go into its own package.

I think one of the reasons that Joachim's past attempt was unsuccessful (
https://github.com/nomeata/packages-base) is that it tried to be too
modular. If we focus on a fewer number of chunks, it would be perhaps
easier.

On Tue, Oct 30, 2018 at 10:03 AM Daniel Cartwright <chessai1996 at gmail.com>
wrote:

> Data.Unique could probably be split off.
>
> A few modules that depend on the event manager might have to be split off
> (e.g. System.Timeout)
>
> Control.Concurrent is weird because it also has the 'Fd' stuff in it, not
> sure how that would work - split off into the event manager package? since
> there's a cyclic dependency there while those exist in Control.Concurrent.
>
> Weak ptrs and Stablenames are basically wrappers around primops, so i'm
> unsure if those should stay or go.
>
> On Tue, Oct 30, 2018 at 9:40 AM Daniel Cartwright <chessai1996 at gmail.com>
> wrote:
>
>> I agree with those.
>>
>> On Tue, Oct 30, 2018 at 9:35 AM Andrew Martin <andrew.thaddeus at gmail.com>
>> wrote:
>>
>>> Here's my stab at a more aggressive split:
>>>
>>> * base: everything not removed by the libraries below
>>> * concurrency: all Control.Concurrent.* modules (depends on base)
>>> * foreign: all Foreign.* modules (depends on base)
>>> * event-manager: all GHC.IO.* modules, System.Timeout (depends on base,
>>> foreign, concurrency)
>>>
>>> There would be some additional trickery. The stuff in Control.Concurrent
>>> that deals with event registration would need to be moved somewhere else.
>>> But I think this would more-or-less work.
>>>
>>> On Tue, Oct 30, 2018 at 8:54 AM Andrew Martin <andrew.thaddeus at gmail.com>
>>> wrote:
>>>
>>>> For additional clarity, I should mention that I am looking for
>>>> low-hanging fruit here. The higher and tastier fruit would of course be
>>>> splitting out the event manager and all the file handle logic with it. But
>>>> that would be difficult, both in terms of the actual work required and in
>>>> terms of achieving a consensus.
>>>>
>>>> On Tue, Oct 30, 2018 at 8:47 AM Andrew Martin <
>>>> andrew.thaddeus at gmail.com> wrote:
>>>>
>>>>> We could also move out all the modules underneath Control.Concurrent
>>>>> (but not Control.Concurrent itself) except for the MVar module. We would
>>>>> have to leave that one because there is a bunch of other stuff in base that
>>>>> uses MVar. These modules have demonstrated less stability than
>>>>> System.Console.GetOpt and Text.Printf, and there are competing
>>>>> implementations in other libraries.
>>>>>
>>>>> On Tue, Oct 30, 2018 at 8:42 AM Andrew Martin <
>>>>> andrew.thaddeus at gmail.com> wrote:
>>>>>
>>>>>> The benefit is certainly small, and it probably would discourage
>>>>>> using the API. I don't think that the migration path would be tricky. The
>>>>>> new package would just reexport Text.Printf when built with base < 4.13,
>>>>>> and it would define it when built with base >= 4.13. All that is required
>>>>>> is a build-depends line. However, people really shouldn't be using this API
>>>>>> in library code. Other modules in base provide more efficient and more
>>>>>> type-safe ways handle most of the situations I've seen this used for.
>>>>>>
>>>>>> I've never used System.Console.GetOpt (I'm typically use
>>>>>> optparse-applicative for option parsing), but yes, I think that would also
>>>>>> be a good candidate. Since there are multiple competing approach for
>>>>>> argument parsing in the haskell ecosystem, my preference would be to avoid
>>>>>> blessing any of them with inclusion in base.
>>>>>>
>>>>>> I don't feel particularly strongly about either of these, but their
>>>>>> position in base feels odd. They both feel like the result of applying a
>>>>>> "batteries included" mindset to a standard library that has by and large
>>>>>> refrained from including batteries.
>>>>>>
>>>>>> On Tue, Oct 30, 2018 at 8:17 AM Herbert Valerio Riedel <
>>>>>> hvriedel at gmail.com> wrote:
>>>>>>
>>>>>>>
>>>>>>> On 2018-10-30 at 08:04:59 -0400, Andrew Martin wrote:
>>>>>>> > Here's an idea for this I had last night. It's narrowly scoped,
>>>>>>> but I think
>>>>>>> > it moves us a tiny bit in the right direction. We could move
>>>>>>> Text.Printf
>>>>>>> > out of base and into its own library. This doesn't really belong
>>>>>>> in base.
>>>>>>> > The interface it provides it somewhat opinionated, and it's not
>>>>>>> even
>>>>>>> > type-safe. The new library could be named `printf` and could live
>>>>>>> under the
>>>>>>> > haskell github organization. Any thoughts for or against?
>>>>>>>
>>>>>>> Ok, but what does this effectively achieve?
>>>>>>>
>>>>>>> Text.Printf is an API that has been extremely stable and doesn't
>>>>>>> significant evolve anymore; I don't think it has contributed to major
>>>>>>> ver bumps in recent times, nor is it likely to. So I don't see much
>>>>>>> of a
>>>>>>> compelling benefit in doing so. The effect I'd expect if we do this
>>>>>>> is
>>>>>>> that `Text.Printf` will be reached for less (which some might argue
>>>>>>> to
>>>>>>> be a desirable effect -- but you're effectively pushing this API to a
>>>>>>> path of slow legacy death due to reduced discoverability, IMO), as
>>>>>>> the
>>>>>>> convenience of using it is reduced by requiring adding and
>>>>>>> maintaining
>>>>>>> an additional `build-depends` line to your package descriptions, as
>>>>>>> well
>>>>>>> as having to deal with the subtly tricky business of handling the
>>>>>>> migration path pre/post-split (c.f. the `network-bsd` split currently
>>>>>>> being in progress).
>>>>>>>
>>>>>>> Btw, a related extremely stable API in base I could think of which
>>>>>>> people might argue doesn't belong into `base` either is maybe
>>>>>>> `System.Console.GetOpt`; would you argue to split that off as well?
>>>>>>> _______________________________________________
>>>>>>> Libraries mailing list
>>>>>>> Libraries at haskell.org
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>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> -Andrew Thaddeus Martin
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> -Andrew Thaddeus Martin
>>>>>
>>>>
>>>>
>>>> --
>>>> -Andrew Thaddeus Martin
>>>>
>>>
>>>
>>> --
>>> -Andrew Thaddeus Martin
>>> _______________________________________________
>>> Libraries mailing list
>>> Libraries at haskell.org
>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries
>>>
>>
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