I think it's essential to be able to *read* pickles generated by older Python versions. But for writing I'm okay with only writing protocol 2 (which Python 2.x also understands) and only supporting the modern APIs for customizing pickle writing.
I don't think classic class instances are necessarily unpicklable in 3.0 -- they will just show up as instances of the corresponding new-style classes. --Guido On 10/3/07, Neil Schemenauer <[EMAIL PROTECTED]> wrote: > I guess the library overhaul hasn't really started it but it would > be nice if the pickle module could get some work. Today I'm trying > to efficiently store a class using pickle and the documentation is > making my head hurt. I don't think the documentation itself is the > problem, just the fact that the rules are so complicated. > > I guess there are several different solutions: > > * Remove backwards compatible stuff from the code and the > documentation. The downside is that old pickles could not be > loaded. Perhaps that's not a huge issue since the removal of > old-style classes might already break old pickles. > > * Remove the backwards compatible stuff from the documentation > only. The would help people using the language but would > still be a long term maintenance issue. > > * Leave the old code in but generate warnings when old pickle > mechanisms are used. Eventually the old stuff could be > removed from the code. > > * Provide an "oldpickle" module the supports pre-3k pickles. > > I think I like the warnings idea best. > > Neil > > _______________________________________________ > Python-3000 mailing list > Python-3000@python.org > http://mail.python.org/mailman/listinfo/python-3000 > Unsubscribe: > http://mail.python.org/mailman/options/python-3000/guido%40python.org > -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
