[Python-Dev] PEP 328

[Terry Reedy]

"Thomas Wouters" <thomas at xs4all.net> wrote in message 
news:20060225182601.GQ23859 at xs4all.nl...
> The one open point that Aahz forwarded me, and is expressed somewhat in
> http://mail.python.org/pipermail/python-dev/2004-September/048695.html , 
> is
> the case where you have a package that you want to transparently supply a
> particular version of a module for forward/backward compatibility, 
> replacing
> a version elsewhere on sys.path (if any.) I see four distinct situations 
> for
> this:

Did you mean three?

> 1) Replacing a stdlib module (or a set of them) with a newer version, if 
> the
>    stdlib module is too old, where you want the whole stdlib to use the
>    newer version.
>
> 2) Same as 1), but private to your package; modules not in your package
>    should get the stdlib version when they import the 'replaced' module.
>
> 3) Providing a module (or a set of them) that the stdlib might be missing
>    (but which will be a new enough version if it's there)

Or did you forget the fourth?

In any case, the easy solution to breaking code is to not do it until 3.0. 
There might never be a 2.7 to worry about.

Terry Jan Reedy