How to make an empty generator?
Steven D'Aprano
steve at REMOVE-THIS-cybersource.com.au
Thu Feb 18 19:32:03 EST 2010
On Thu, 18 Feb 2010 17:30:54 -0600, Robert Kern wrote:
> > If all you want is a generator that doesn't yield anything, then
> > surely there isn't any one-time processing and you don't need the
> > comment?
>
> Sure there is. Python doesn't know that nothing gets yielded until it
> hits the return statement before the yield. When it calls .next() on the
> iterator, the code elided by the comment executes, then the return is
> hit, a StopIteration exception is raised, and the iteration is complete.
I don't understand why you care about having *any* code before the
StopIteration. That's like:
def empty():
for x in range(1000):
pass # Spin wheels uselessly
return
yield
What's the point of the wheel spinning? Did I miss something?
--
Steven
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