Versioning Libraries

Peter Hansen peter at
Fri Dec 3 12:42:42 CET 2004

Richard Brodie wrote:
> "Peter Hansen" <peter at> wrote in message news:coog1l$mip$1 at
>>Python is exceptionally backwards compatible, so generally
>>code from an older version will run unchanged on newer
> I'm just curious: why exceptionally? I like Python for a lot of
> reasons but I wouldn't put API stability high on the list.
> Not compared with a traditional language like C or Fortran,
> anyway. Which languages go around breaking backwards
> conmpatibility in a cavalier way?

Anything from Microsoft, for a start.

Anyway, you're confusing "instability" (I hate that word,
it has connotations of unreliability, which aren't intended)
with "enhancement".  The API gets changed, yes, but by
adding new things, almost never by removing the old stuff
or changing how it works.  You are free to ignore the new
stuff, and almost all old code will work unchanged.  That's
what backwards compatibility means, not that no new features
are ever added.


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