Re: [gentoo-dev] [Volunteers needed] Communicating use (and existence) of USE_PYTHON

[Richard Freeman]

On 12/03/2010 07:05 AM, Michał Górny wrote:
> On Fri, 03 Dec 2010 11:35:14 +0100
> Sebastian Pipping <sping@g.o> wrote:
>
>> to better communicate USE_PYTHON we could use:
>
> The first question that comes into my mind is -- why do we need
> to communicate that? I think that USE_PYTHON is a pretty specific
> variable which should be used only if specially required (i.e. to keep
> multiple Python versions ready for use).

I tend to agree.  For a user who doesn't actually USE python, but just
has it installed because half of the rest of the system doesn't work
without it, python is just another dependency.  If a package only works
with python v1.2, then it should depend on the appropriate slot/etc.

If a user actually USES python, then they should have a mechanism to
tell the system what versions of python to keep around.  If you could
put slots in the world file that might do the trick, but this variable
seems like a reasonable way to do it as well.

>
> What needs to be fixed IMO is the default value of that variable.
> If you already disabled switching the active Python version by default,
> you should also make the Python eclass base its' USE_PYTHON defaults
> on the active Python version.

I tend to agree here as well.  The distro should manage the version used
for distro packages.  Maybe a user wants to do cutting-edge development
work in python-v12.  The system should still use a sane version of
python to run portage/etc, unless the user specifically tells it to do
otherwise.

Rather than hard-coding this in every package a distro-wide default
probably makes sense.  When new versions of python are deemed acceptable
for distro-wide use the default can be updated.

Gentoo has to work reasonably well without having to micro-manage python
versions.  Users shouldn't have to figure out what version of python
they want to run to do an install.

Rich