Python: Variable from higher scope "referenced before assignment"

Question

Suppose I have a method foo:

def foo(string):
    def bar1():
        if '1' in string:
            string = string[2:]
        else:
            bar2()

    def bar2():
        if ('2' in string):
            string.insert(5, '1')
        else:
            string.insert(5, '2')

    bar1()

Unfortunately, this returns an error stating that local variable string was referenced before assignment. I thought that string would be inherited from foo's scope. Was I wrong? Note that the variable string is actually a list (sorry for the confusion).

Try to pass string into bar1() like this: def bar1(string). – clarity Nov 11 '16 at 18:27 — clarity, Nov 11 '16 at 18:27

score 2 · Accepted Answer · answered Nov 11 '16 at 18:29

2

Assignments to variables create a new variable in the local scope, unless the nonlocal keyword is used (Python 3 only):

https://www.python.org/dev/peps/pep-3104/

answered Nov 11 '16 at 18:29

Amber

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Python: Variable from higher scope "referenced before assignment"

1 Answers1