On Mon, May 26, 2008 at 11:59 AM, Raymond Hettinger <[EMAIL PROTECTED]> wrote: >> * The 2.6-backported Mapping ABC has the 3.0 dict API, >> that is, it uses keys() that returns a view etc. > > Curious to hear what Guido thinks about this one. > A nice use of the Mapping ABC is to be able to > get 3.0 behaviors. I thought that was the whole > point of all these backports. If the ABC gets altered, > then it just makes the 2-to-3 conversion harder.
It's wrong if the ABC doesn't describe the behavior of actual implementations; that is its primary purpose, the mixin class is a nice side benefit. We could make the incompatible mixin classes available separately though, if you think they're useful. >> * The 2.6 UserDict is not registered as a mapping. > > Since the API's are not currently the same, it makes > sense that UserDict is not registered. > If the Mapping ABC does get changed, only IterableUserDict > should get registered. A regular UserDict does not comply. Fair enough. I recomment to fix the Mapping ABC and register IterableUserDict. >> * collections.deque isn't registered as a MutableSequence. > > Deque's do not support count(), insert() or __iadd__(). > They should not be registered. General purpose indexing > into a deque is typically a mis-use of the data structure. > It was provided only to make it easier to substitute for lists > in apps the operate only one ends (i.e.d[0], d[1], d[-1], d[-2] > but not d[i] to somewhere in the middle). Hopefully they aren't registered in 3.0 either. :-) >> If there are no objections, I will correct these issues >> in the 2.6 and 3.0 branches. > > I think none of these changes should be made. I'm in the middle. :-) -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
