2010/6/3 Tal Einat <report@bugs.python.org>:
>
> Tal Einat <taleinat@users.sourceforge.net> added the comment:
>
> In my mind, the reason for this patch is that xrange/range can be thought of as a lazy list of integers. However without this patch, membership checking was done trivially instead of in a "smart/lazy" manner, which is unexpected for users. Finally, conditions such as "num in xrange(3, 1000, 5)" are not trivial to express correctly otherwise, and even more so for negative steps.
>
> This patch is already implemented and accepted for 3.2, I just wish to back-port it to 2.7 which should be fairly straightforward.
>
> I'll just have a patch ready by tomorrow, and hope that someone finds the time to review it and possibly commit it in time for rc1. I realize that this is a minor change at the last minute. I will certainly understand if the people responsible for preparing rc1 are too busy for this.

xrange has behaved like this for such a long time that I don't see
what it buys us to commit the patch this late.