Question

How would I make a function where one variable (exit) determines whether a ‘while’ loop runs or not and be able to change it in a different function so that the while loop in the first function will stop

    while exit == 0:
       option = (raw_input("What would you like to do? "))
       if option == exit:
          exit()
    def exit():
       exit = 1

That is just an example of what I am trying to do.

When I try running it it doesnt leave the while loop and in doing so doesn’t end the program. How can I make it so that the while loop recognizes that exit is now 1 and leaves the loop?
Sorry if the question isn’t very good because this is my first time using stackoverflow to ask a question.

ADDITION: I want to kno how to change the variable across functions because I will be doing that in parts of the program. Also, I am going to be saving data before exit so that is why I have the ‘exit’ in a different function

Answer 1

Your problem here is scope – exit is local to the function exit() so doesn’t affect the variable exit in the loop scope.

A better solution is this:

exit = False
while not exit:
    option = raw_input("What would you like to do?")
    if option == "exit":
        exit = True

Or simply:

while True:
    option = raw_input("What would you like to do?")
    if option == "exit":
        break

Note the use of True and False over 1 and 0 – this is more pythonic, as what you mean here is truth values, not integers. I also changed to compare to the string "exit", as I presumed that was what you wanted, not comparing the user input to the value of exit.

If your problem is you want to have the same scope, you might want to make your code part of a class.

class Doer: #Naturally, give it a real name based on it's purpose.
    def __init__(self):
        self.exit = False
        while not self.exit:
            option = raw_input("What would you like to do?")
            if option == "exit":
                self.exit()

    def exit(self):
        self.exit = True

Here exit is an instance variable (hence being accessed from self) and therefore both times we are referencing the same variable.

If your code is not a simplification of a more complex problem, this is largely overkill, as one of the first solutions would be more appropriate.