Python return statement error " 'return' outside function"

Question

When running the following code (in Python 2.7.1 on a mac with Mac OS X 10.7)

while True:
    return False

I get the following error

SyntaxError: 'return' outside function

I've carefully checked for errant tabs and/or spaces. I can confirm that the code fails with the above error when I use the recommended 4 spaces of indentation. This behavior also happens when the return is placed inside of other control statements (e.g. if, for, etc.).

Any help would be appreciated. Thanks!

What the interpreter says, you're not inside a function. Control statements aren't functions, you define a function with `def`. — CB Bailey, Oct 20 '11 at 20:56
I use `yield` which gives me the same error, reason is the same, shall be in a function.. — , Jul 29 '14 at 09:41

score 68 · Accepted Answer · answered Oct 20 '11 at 21:05

68

The return statement only makes sense inside functions:

def foo():
    while True:
        return False

answered Oct 20 '11 at 21:05

Raymond Hettinger

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Raymond, did you get so many rep points that your counter rolled back over to 0? – PaulMcG Oct 20 '11 at 21:18
@PaulMcGuire: your comment confuses me. – Hovercraft Full Of Eels Oct 20 '11 at 21:31
@PaulMcGuire His account has only existed for three days. – agf Oct 20 '11 at 22:05
8

I will be naming name my first child @Raymond-Hettinger – Jeff Oct 20 '11 at 23:29
I have been losing sleep over this – Edwinner Jun 28 '14 at 15:02

score 31 · Answer 2 · edited Oct 13 '17 at 16:55

31

Use quit() in this context. break expects to be inside a loop, and return expects to be inside a function.

edited Oct 13 '17 at 16:55

Antonio

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answered Feb 09 '14 at 02:09

buzzard51

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This works in case you just want to stop the script, as you would do with a void return. I'd rather use sys.exit() though, because then an exit status can be specified. Check this question: http://stackoverflow.com/questions/543309/programatically-stop-execution-of-python-script – Guillem Cucurull Feb 23 '16 at 15:41

score 12 · Answer 3 · answered Oct 20 '11 at 21:45

12

To break a loop, use break instead of return.

Or put the loop or control construct into a function, only functions can return values.

answered Oct 20 '11 at 21:45

Jürgen Strobel

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score 3 · Answer 4 · answered Mar 28 '17 at 22:13

3

As per the documentation on the return statement, return may only occur syntactically nested in a function definition. The same is true for yield.

answered Mar 28 '17 at 22:13

Eugene Yarmash

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Python return statement error " 'return' outside function"

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