[Distutils] early preview of pythonv

[Carl Meyer]

Jim,

On 03/16/2011 08:00 AM, Jim Fulton wrote:
[snip]
> buildout.  In particular, I know of 2 basic use cases:
> 
> - Get complete isolation from local additions relative to the standard
>   Python distribution.

This is the primary design goal, and I believe it's currently achieved.
To be clearer, we have isolation from the system Python's site-packages
and site-python (site directories added to sys.path in site.py), where
all non-stdlib modules should go. We are not isolated from any changes
to the system Python's standard library (which should never be changed
anyway); this is intentional and matches the current behavior of
virtualenv, and avoids the necessity of copying the entire stdlib.

> - Have the ability to cherry pick some local additions while having
>   isolation from the rest. (Gary and Ubuntu, I'm looking at you.)

We don't currently have this. There's a question whether this behavior
should be built in to pythonv, or provided by a tool like distutils2 or
pip or buildout that could be virtual-aware. The latter seems like
perhaps a more natural fit, since it's a persistent modification of the
virtualenv's working set, parallel to installing or uninstalling
packages within the virtualenv. I'm open to further thoughts on this
question.

Carl