[Mark J. Nenadov]
I also use 2.0 as the lowest common denominator.
Linguistic problem :-). Should we say "greatest" instead of "lowest"? Granted that the greatest common denominator is not "greatest" in any other way, but it is lower or equal than any of the things we consider. The real "lowest" common denominator might be very close to nothing, might it not?
I believe that maintaing and improving the language usually is more important than maintaining consistency between versions. That being said, going overboard with changes isn't good either. I think documenting these changes would be a step in the right direction.
Exactly. The changes _are_ documented in detail, indeed, but in special documents which only serious users read when they about to migrate from one version to another. I'm thinking about users who use the language occasionally or even regularly, but not fanatic about following everything about versions -- they mainly rely on the Python Library Reference, or even the Python Language Reference.
These references describe some Python, but not necessarily the Python which happens to run on a given machine, and I guess (without having really experienced this myself) it might be frustrating to read and study, for discovering soon after that the feature is unavailable in this version. Or even, for someone, to have handy information about how to write for the common denominator, without having to compare many printings of the references at various Python levels. I guess that notes or footnotes, about Python levels in which described features have been implemented, might help users having to cope with release lags between Linux releases. Such lags are unavoidable whenever Python evolves.
I understand the effort it would require to add and maintain such notes in the references (especially for the Library Reference which has myriad of details, the Language Reference is more clearly cut), my hope is that this might remove some of the irritation people seem to show.
-- François Pinard http://www.iro.umontreal.ca/~pinard