George Sakkis <[EMAIL PROTECTED]> wrote: > Paul Rubin wrote: > > > [EMAIL PROTECTED] (Cameron Laird) writes: > > > For that matter, would it be an advantage for len() to operate > > > on iterables? > > > > print len(itertools.count()) > > > > Ouch!! > > How is this worse than list(itertools.count()) ?
It's a slightly worse trap because list(x) ALWAYS iterates on x (just like "for y in x:"), while len(x) MAY OR MAY NOT iterate on x (under Cameron's proposal; it currently never does). Yes, there are other subtle traps of this ilk already in Python, such as "if y in x:" -- this, too, may or may not iterate. But the fact that a potential problem exists in some corner cases need not be a good reason to extend the problem to higher frequency;-). Alex -- http://mail.python.org/mailman/listinfo/python-list
