[Python-apps-team] Bug#787902: Bug#787902: pelican: Please provide a python3 module

[Vincent Cheng]

On Mon, Jun 15, 2015 at 11:54 PM, Johannes Schauer <josch at debian.org> wrote:
> Hi,
>
> Quoting Vincent Cheng (2015-06-16 07:18:24)
>> Thanks for the patch! However, as pelican is intended to be used more as an
>> application (it's a static site generator), rather than a set of standalone
>> python modules, I don't think it particularly makes sense to offer both a
>> python2 and python3 version of pelican. I'm inclined to just build
>> src:pelican using whatever is the default version of python in Debian, and
>> eventually rename the binary python-pelican package to just pelican.
>
> I'm neither very familiar with Python packaging nor with the plan to transition
> from Python2 to Python3, but naively I would've thought that when the change of
> the default Python version happens would also depend on the number of packages
> that do not anymore depend on Python2, no? So would any such transition in the
> future not be made easier or earlier if the number of Packages that still
> (Build-)Depend on Python2 would be lower? Sure, pelican is just one small
> package among thousands so what an impact can it make? But, again naively, I
> would've thought that if every tiny package pushes its transition from 2 to 3
> into the future, then together they will lead to the switch of the default
> version from 2 to 3 being later than earlier. You say that it would not make
> much sense to offer both versions at the same time and that is a valid
> argument. But what stops src:pelican from just offering the Python 3 version in
> a "pelican" binary package now?

I haven't been keeping up with all the traffic from debian-python
lately, but my understanding of the current situation is that python
libraries/modules should have both python2 and python3 binary packages
whenever possible (or be ported to python 3 if not yet already
ported), while python application maintainers are free to choose to
use either python2 or python3. IMO for python applications, it makes
sense to just depend on whatever python version is currently the
default, so that end users (many of who are not necessarily python
developers and consider this an implementation detail they don't care
about) end up with just a single (default) version of python
installed.

Regards,
Vincent