PEP 405 vs 370

[Ian Kelly]

On Fri, May 25, 2012 at 1:45 PM, Damjan Georgievski <gdamjan at gmail.com> wrote:
> http://www.python.org/dev/peps/pep-0405/
>
> I don't get what PEP 405 (Python Virtual Environments) brings vs what we
> already had in PEP 370 since Python 2.6.
>
> Obviously 405 has a tool to create virtual environments, but that's trivial
> for PEP 370 [1], and has support for isolation from the system-wide site
> patch which could've been added in addition to PEP 370.
>
> So maybe I'm missing something?

Virtual environments entail not just isolation from the system
environment, but also the ability to switch between different virtual
environments on demand.  A single user site-packages directory can't
easily support that.

The two PEPs are related but geared toward very different purposes.
Virtual environments are for setting up a multitude of environments in
order to support running scripts with different requirements or
configurations on a single platform.  The user site-packages directory
is for augmenting the static system environment with packages desired
by individual users, who can't or simply don't want to install the
package for all users of the system.

Cheers,
Ian