[EMAIL PROTECTED] wrote:
> I've also previously run into the same need as the original poster. I
> no longer recall the details, but I think maybe I was implementing a
> union/find type algorithm. This basically involves partitioning a
> universe set into partitions, where any element of a partition can be
> used as a name/handle/etc for the partition in question. Sets are the
> obvious representation for these partitions, esp since they implement
> union efficiently. And given this representation, it's very obvious
> to want to generate a "name" when you have a set in hand. Since any
> element of the set serves as a name (and you know the sets are all non-
> empty), it'd be very nice to have a .element() method, or some such.
> I guess "iter(s).next()" works okay, but it's not very readable, and I
> wonder if it's efficient.
You can find out::
$ python -m timeit -s "s = set('abcdef')" "x = iter(s).next()"
1000000 loops, best of 3: 0.399 usec per loop
$ python -m timeit -s "s = set('abcdef')" "x = s.pop(); s.add(x)"
1000000 loops, best of 3: 0.339 usec per loop
So it looks like it's more efficient to use s.pop() + s.add().
STeVe
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