Is there an unbounded version of range (or xrange for Python 2), or is it necessary to define it manually? For example

squares = (x*x for x in range(n))

can only give me a generator for the squares up to (n-1)**2, and I can't see any obvious way to call range(infinity) so that it just keeps on truckin'.


You're describing the basic use of itertools.count:

import itertools
squares = (x*x for x in itertools.count())