[Python-Dev] PEP 364, Transitioning to the Py3K standard library

[Brett Cannon]

On 3/7/07, Barry Warsaw <barry at python.org> wrote:
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> On Mar 7, 2007, at 4:36 PM, Brett Cannon wrote:
>
> >> >> Third party package renaming is also supported, via several public
> >> >> interfaces accessible by any Python module.
> >> >>
> >> >
> >> > I guess a .pth file could install the mappings for the third-party
> >> > modules.
> >>
> >> How would that work?  .pth files don't execute arbitrary Python code,
> >
> > It does through imports, though.
>
> I think it's important to import on demand only though.

And I agree.

> I should
> probably make that clear in the PEP <wink>.  IOW, "import email"
> should not by side-effect import all sub-modules just because there's
> a remapping involved.  This actually would be quite easy to do, but
> it's one of the reasons why the Python 2.5 email package hack goes
> through so much trouble.
>

I am not suggesting that every rename be imported.  All I am saying is
that a .pth file could ``import pkg.old_names`` and that old_names
module adds the mappings, that's all.  It doesn't do anything that you
are not proposing be done automatically.

-Brett