[Python-Dev] xrange vs generators
Guido van Rossum
guido@digicool.com
Mon, 25 Jun 2001 10:47:50 -0400
[me]
> > Although xrange() objects currently support some sequence algebra,
> > that is mostly bogus and I don't think anyone in their right mind uses
> > it.
[theller]
> I _was_ using xrange as sets representing (potentially large)
> ranges of ints.
> Example:
>
> positive = xrange(1, sys.maxint)
>
> if num in positive:
> ...
>
> I didt follow the iterators discussion: would this
> continue to work?
No, it would break. And I see another breakage too:
r = xrange(10)
for i in r:
for j in r:
print i, j
would not do the right thing if xrange() returned an iterator (because
iterators can only be used once).
This is too bad; I really wish that xrange() could die or be limited
entirely to for loops. I wonder if we could put warnings on xrange()
uses beyond the most basic...?
--Guido van Rossum (home page: http://www.python.org/~guido/)