Serious Menu Error Handling

Starter Code

def main():
    # (label, function)
    menu_options = [
        ("First Option", first_option),
        ("Second Option", second_option),
        ("Third Option", third_option),
        ("Fourth Option", fourth_option),
    ]

    running = True
    while running:
        # display menu
        print("Choose an option.\n")
        for i, (label, function) in enumerate(menu_options):
            print(f"{i + 1} - {label}")
        print()
        print("'q' to quit")
        
        # Get choice
        choice = int(input("> ")) - 1

        # extract function from list
        label, function = menu_options[choice]

        # run the extracted function
        function()
        print()


def first_option():
    print("RUNNING FIRST OPTION")


def second_option():
    print("RUNNING SECOND OPTION")


def third_option():
    print("RUNNING THIRD OPTION")


def fourth_option():
    print("RUNNING FOURTH OPTION")


if __name__ == "__main__":
    main()

What you should do

This program has some serious issues. It doesn’t work properly and has the potential to raise a number of errors. Fix the following favouring try/except as much as possible. Your solution may refactor the code significantly, which is fine. Just preserve the concept of keeping the menu options in a list.

• ValueError: When the program gets the user choice and they enter a non-int.

• The program needs a way to quit when they enter a 'q'.

• If the user enters a menu option 0 or lower, it will pick out the functions from the back. For example, if the user enters 0, the program will subtract 1 to get -1, then it will pull out the function associated with menu_options[-1] which is the last menu option. This should not be allowed.

• IndexError: When the user enters a number higher than 4 and the program tries to access that index in the menu_options list.

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©2021 Daniel Gallo

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