How to write Python generator function that never yields anything

python generator yield
John Zwinck picture John Zwinck · Jun 7, 2011 · Viewed 11.7k times · Source

I want to write a Python generator function that never actually yields anything. Basically it's a "do-nothing" drop-in that can be used by other code which expects to call a generator (but doesn't always need results from it). So far I have this:

def empty_generator():
    # ... do some stuff, but don't yield anything
    if False:
        yield

Now, this works OK, but I'm wondering if there's a more expressive way to say the same thing, that is, declare a function to be a generator even if it never yields any value. The trick I've employed above is to show Python a yield statement inside my function, even though it is unreachable.

Answer

Sven Marnach picture Sven Marnach · Jun 7, 2011

Another way is

def empty_generator():
    return
    yield

Not really "more expressive", but shorter. :)

Note that iter([]) or simply [] will do as well.

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