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I'm creating a generator that gets consumed by another function, but I'd still like to know how many items were generated: lines = (line.rstrip('\n') for line in sys.stdin) process(lines) print("Processed {} lines.".format( ? )) The best I can come up with is to wrap the generator with a class that keeps a count, or maybe turn it inside out and send() things in. Is there an elegant and efficient way to see how many items a generator produced when you're not the one consuming it in Python 2? Edit: Here's what I ended up with: class Count(Iterable): """Wrap an iterable (typically a generator) and provide a ``count`` field counting the number of items. Accessing the ``count`` field before iteration is finished will invalidate the count. """ def __init__(self, iterable): self._iterable = iterable self._counter = itertools.count() def __iter__(self): return itertools.imap(operator.itemgetter(0), itertools.izip(self._iterable, self._counter)) @property def count(self): self._counter = itertools.repeat(self._counter.next()) return self._counter.next()

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