Iterator execution hangs after the iterator is exhausted

I have a generator function that takes iterator object and performs some logic on every item. This runs on a larger list of iterations. It then yields the result back to the calling code, so it can break the for and while loop

def func(it):
    item = next(it)
    item = item.execute()
    yield item

it = iter(range(1, 10))

condition = True
while condition:
    for item in func(it):
        condition = item
        print condition

Executing this code in Python IDLE, prints the follows and hangs:

1
2
3
4
5
6
7
8
9

I need to CTRL+C to break out the loops. If I use regular range(10) so the loop starts with the value 0, it breaks immediately (since condition=0 ) and return prompt.

What am I missing? Why my iterator hangs when exhausted?

---

The iterator isn't the one hanging, it's your while loop. Since condition ends at 9 , the while loop becomes while 9 which never exits. Take out the while loop completely.

for item in func(it):
    condition = item
    print condition

Or, if you want to stop if the condition is false, then:

for item in func(it):
    condition = item
    print condition
    if not condition: break

---

The for loop is not hanging. The outer while loop is. You have set it to run forever as condition changes from 1-9 and then remains as 9. So, code executes to:

while 9

which always returns True and this becomes an infinite loop.

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