Re: Merging the purge-python2-packages branch

[zimoun]

Hi Maxim,

On lun., 30 mai 2022 at 11:32, Maxim Cournoyer <maxim.cournoyer@gmail.com> 
wrote:
> zimoun <zimon.toutoune@gmail.com> writes:
>> On lun., 30 mai 2022 at 09:25, Maxim Cournoyer <maxim.cournoyer@gmail.com> 
>> wrote:
>>
>>> Most of the removal were automated using a script [0], but each package
>>> removed had their upstream status considered (using last commit or
>>> existing patches for Python 3 compatibility) and quite a few were saved
>>> that way.
>>
>> These packages perfectly build.
>
> On Python 2, that is :-).

Yeah. :-)  Another point of view:

        Well, me, personally, I continue to do most of my research using
        Python 2 because I cannot afford to port everything to Python
        3. And since I do only number crunching, meaning nothing with
        security implications, I am not particularly worried.

        [...]

        Once Python 2 lives in a largely isolated package sub-universe,
        I don't see much harm keeping it in Guix for now. If security
        issues become apparent, we might have to do something more
        drastic.

        <https://yhetil.org/guix/m1a78p5tgf.fsf@fastmail.net>


And if you filter by ’python2-’ from the dashboard,

    <http://ci.guix.gnu.org/eval/359297/dashboard>
    
many are broken but many are still fine.

BTW, ’python2-biopython’ is broken in the branch
’purge-python2-packages’ and still there [1].

1: <http://ci.guix.gnu.org/build/827139/details>


> This effort is an attempt to reduce our dependencies on Python 2 as much
> as possible, so that we can hopefully remove Python 2 from our tree
> before 2030 comes ;-).

I agree and I am advocating since 2019-10-31 [2] for an explicit
plan. :-) However, my understanding of this plan after several
discussions is: remove the python2- variants once they are broken.

It appears to me surprising: we do not provide a schedule for the
removals, then bang purge.

2: 
<https://yhetil.org/guix/CAJ3okZ33HsXxgVgK3XyVHvYUfDUrbcwBnOn7FC6=3AG_YvAUbQ@mail.gmail.com>


Well, as a hobbyist, I am fine with such purge.  As a scientific
practitioner using Guix at work, it is more annoying…

>> bamm             /gnu/store/17hs9c60isdk8sfkpi0280xzc0gkyxn1-bamm-1.7.3

[...]

>> Therefore, I would not remove them; I have not checked which python2-
>> dependencies they are using.
>
> If something is valuable up there, I'd suggest interested parties
> contribute them to the Guix-Past channel.

…for instance, I use time to time the package ’bamm’.  Because inferiors
and time-machine, the removal of ’bamm’ is not a big deal per se but I
need some time to adapt some scripts, etc.

Other said, I am fine with the purge and I volunteer to help in
transferring from master to guix-past but we need a schedule,
communicate on the purge and more importantly say when it will
happen. :-) (maybe not a purge 2-3 days after an announcement on
guix-devel following 2 weeks in a branch ;-))


Cheers,
simon

PS: Great script, BTW. :-)