The looming Python 3(000) monster

[Arthur Pemberton]

2008/12/5 Toshio Kuratomi <a.badger at gmail.com>:
> Michael DeHaan wrote:
>>
>> This isn't a huge problem to those who are only developing on the latest
>> Fedora, per-se (other than getting over the initial hump), but it's
>> pretty bad for someone who wants to keep a single codebase across EL 4
>> (Python 2.3) and up, which I think a lot of us do.   That gets to be
>> darn impossible and we have to double our involvement with code because
>> we essentially have to maintain a differently-compatible fork for each
>> project.
>>
> This is a problem that hasn't been brought up before.  We can keep
> Fedora going on python-2.6, 2.7 (and 2.8 if it occurs) and gradually
> move code close to py3.x-ish syntax by using the "from __future__ import
> *" mechanism.  But that doesn't help with older distros running
> python-2.5 or less.  I don't believe there's anyway around that, though.
>
> As we move to python-2.6+ w/ 3.x features we'll have this problem no
> matter when we actually move to python-3.  So we eventually (unless we
> hold off on moving to python3 until python-2.6 is standard on all RHEL
> releases) will be maintaining two trees of code no matter what.
>
> If we maintain a python2 package and a python3 package in one version of
> Fedora we'll have even more work.  Right now we can have an EL-5 and
> Fedora-9&10 package that are compatible with 2.5.  A different version
> can run on Fedora11 with the syntax ported to python-2.6's understanding
> of what 3.x will be like.  If we have both python2-2.6 and python3-3.0
> in Fedora11 we'll have to maintain separate py2 and py3 packages for
> every python module we ship as well.  We should avoid this if we can.
>
> Note that I think this decision is only partially within the powers of
> the Fedora Project to decide.  If 80% of our upstream libraries move to
> py3, we'll need to move to py3 sooner.  If 80% refuse to move off of
> py2, we can take our time working on migration code.
>
> -Toshio


Maybe I am oversimplifying. But what about using 2.6+ (<3.0) and
ensure that all code is compatible with 3. And still have 3 in
parallel for those who want it. So we target 2.6+ , but have 3.0 there
to ensure everything would work with it, and for early adopters/devs

-- 
Fedora 9 : sulphur is good for the skin
( www.pembo13.com )