Python 3 changing variable in function from another function

Question

I would like to access the testing variable in main from testadder, such that it will add 1 to testing after testadder has been called in main.

For some reason I can add 1 to a list this way, but not variables. The nonlocal declaration doesn't work since the functions aren't nestled.

Is there a way to work around this?

def testadder(test, testing):
    test.append(1)
    testing += 1

def main():
    test = []
    testing = 1
    testadder(test, testing)
    print(test, testing)

main()

Can you elaborate on what `test` and `testing` should be in general? It's a bit hard to understand what you want to do. — Mike Tung, Sep 16 '16 at 13:39

score 1 · Accepted Answer · answered Sep 16 '16 at 13:16

1

Lists are mutable, but integers are not. Return the modified variable and reassign it.

def testadder(test, testing):
    test.append(1)
    return testing + 1

def main():
    test = []
    testing = 1
    testing = testadder(test, testing)
    print(test, testing)

main()

answered Sep 16 '16 at 13:16

Mark Tolonen

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One more thing. Say if I wanted to return more than one variable, would that work as well? Or would I need to split it somehow? – Uninvolved Sep 16 '16 at 13:21
Yes, `return a,b` and `a,b = func()` – Mark Tolonen Sep 16 '16 at 13:23

Python 3 changing variable in function from another function

1 Answers1