[Distutils] Attempted summary of version number thread

[Greg Ward]

Quoth Konrad Hinsen, on 14 December 1998:
> The criterion is that it must be clear both for human users and for
> installation programs
> 1) which of two versions is newer
> 2) if two versions are compatible, i.e. use the same APIs

OK, just to keep everyone on their toes, I'm going to take the
anarchists' side here.  I have said several times that I am against
*imposing* semantics of version numbering, and if I read Konrad right
here that's what he's suggesting: a certain part of the version number
implies "API version".

I don't think this'll work, and not just because Greg and Mark and
Marc-Andre (and probably lots of other people) don't like it.  I do kind
of like it, being a control-freak myself, but I don't think it'll work!
Most developers just don't think *that* carefully about what their
version number means.  Or they might think carefully about it, but come
to different conclusions: if you completely rewrite your software, you
might feel that justifies bumping from 1.x to 2.0 -- even with full API
compatability.  We simply cannot mandate these sorts of details on
something like the world of all Python modules.

Perhaps an "API version number" belongs in the package meta-data, along
with the multitude of variables that John Skaller considers part of the
"version" (again, I think John is talking about something much bigger
than "version numbers", and I think what he's talking about can be
considered package meta-data).

While I think it's a worthy goal to try to automatically handle all
forms of module inter-dependency, I also think it's a vast swamp with no
discernible exit.  The goals for the distutils should be modest: be able
to compare version numbers and express module dependencies in terms of
version numbers.  Expressing compatability on the many axes John
proposes, plus the "API version", would be very difficult.

        Greg
-- 
Greg Ward - software developer                    gward@cnri.reston.va.us
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