Global name is not defined when using global variable

Question

I am learning Python as I go and I am not getting what I am doing wrong with my variables and being to access them in functions.

I have recreated the general layout of my script in PythonFiddle and I got the same error

global trigger

class test(object):
    def init(self):
        trigger = 'hi'
        self.step2()

    def step2(self):
        print '%s' % trigger

if __name__ == "__main__":
    tester = test()
    tester.init()`

Anyone have any ideas?

Answer 1

You need to mark the variable as global in every function where you assign to it. Put global trigger inside your init method.

Note that doing things this way is probably not a great idea. There's not much point to defining a class if it's just going to store its data in a global variable. One alternative would be:

class test(object):
    def init(self):
        self.trigger = 'hi'
        self.step2()

    def step2(self):
        print '%s' % self.trigger

if __name__ == "__main__":
    tester = test()
    tester.init()