Re: Using python + pygtk in Desktop modules (was Re: Revisiting the Gnome Bindings)

["Gustavo J. A. M. Carneiro" <gjc inescporto pt>]

xSeg, 2004-09-27 às 11:15 -0400, Sean Middleditch escreveu:
> On Mon, 2004-09-27 at 11:36 +0200, Murray Cumming wrote:
> > Jonathan said:
> > > I would love to see limited use of python in the desktop release for
> > > GNOME 2.10.
> > 
> > I'd love to see whether this idea can fly, and I like the idea of
> > maintainers getting what they need for their own specific modules.
> > 
> > We all have our different favourite languages, but I think we are all
> > capable of hacking on Python even if we don't all love it [1], so I don't
> > think its use would prevent contributions. And it's already widespread on
> > distros, so I don't think it would be adding a big new dependency. [2]
> 
> The biggest problem with Python that I see is that the Python developers
> constantly break ABI with each release.  User gets a new Python and
> blam, most of their third-party Python apps and libraries stop working.
> There's no way to upgrade your distro without also upgrading most of
> your Python apps and libs with it, which may not be possible for many
> users until someone else does the work for them.  It's just a huge
> hassle.

  That's not true.  Python API and ABI certainly is not broken between
minor releases.  You can expect minor API changes between major
versions, of course.  That's why the modules dir changes between major
releases.  That's also why to some people it looks like python is
breaking the API, while it just had minor API changes but is forcing you
to recompile every module for the new version.

  Also note that between python 2.2 final and 2.3 final 19 months
passed.  That's enought time for 3 GNOME major releases!  I think that's
stable enough for me.

> 
> It's as if the GTK ABI were to break with each minor release version.

  No, it's not.  Python does not break ABI with minor releases.

> There's a reason we don't do that.  I don't think we should have the
> desktop rely on a scripting language that itself doesn't follow the ABI
> stability rules the rest of the GNOME development platform adheres to,
> or the rest of the desktop platform requires.

  Even if Python doesn't break ABI after another 19 months, pygtk can
usually compensate for any differences.  It's just like glib
compensating for API changes in glibc.  Changes in definitions compiled
with which defines (_GNU_SOURCE et al), for example.

> 
> When a Python app or lib can be installed on a system running Python 2.3
> and still work when the machine is upgraded to 2.4, then it would become
> a much more reliable and serious environment to rely on in GNOME.

  Your distribution should pick a python version for you and stick with
it.  PyGTK does not switch to a newer Python version unless it is
already in widespread deployment.

  Regards.

-- 
Gustavo J. A. M. Carneiro
<gjc inescporto pt> <gustavo users sourceforge net>
The universe is always one step beyond logic