[Python-Dev] versioning standards?

Guido van Rossum guido@python.org
Mon, 27 Nov 2000 13:11:54 -0500


> AFAIK, __version__ with a string value is in common usage both
> in modules and classes.

Correct.  This was agreed upon as a standard long ago.  It's probably
not documented anywhere as such.

> BTW, while we're at it: with the growing number of dependencies
> between modules, packages and the Python lib version... how about
> creating a standard to enable versioning in module/package imports ?
> 
> It would have to meet (at least) these requirements:
> 
> * import of a specific version
> 
> * alias of the unversioned name to the most recent version
>   available
> 
> Thoughts ?

This is a major rathole.  I don't know of any other language or system
that has solved this in a satisfactory way.  Most shared library
implementations have had to deal with this, but it's generally a very
painful manual process to ensure compatibility.  I would rather stay
out of trying to solve this for Python in a generic way -- when
specific package develop incompatible versions, it's up to the package
authors to come up with a backwards compatibility strategy.

--Guido van Rossum (home page: http://www.python.org/~guido/)