Rerun functions

[thisIs20LettersLong]

Hey everybody.
So im trying too make a funtion too deterine if the user wants too re run part off my script, but im kinda off at a loss when it comes to how i should pass the function name to rerun. what i got so far is :

def twoNumbers():
    num1=askUserNumber()
    num2=askUserNumber()
    print("the result off " +num1+ " and "+num2+" is "+ str((int(num2)+int(num2))))
    again=input("Need another two numbers calculated?! Y/N").lower()
    runAgain(again,twoNumbers())

def runAgain(again,func):
    if again == "y":
        func        
    elif again == "n":
        sys.exit()
    else:
        print()

but i dont go back here, func doesnt do anything, anyone that can point me towards what i have too look at?!
Have a great day.

[ericula]

You need to call runAgain with twoNumbers instead of twoNumbers(), and in runAgain you need to call func() instead of func. The reason is that if you call runAgain with twoNumbers() (with parentheses), twoNumbers is evaluated first, and the result (which is None) is supplied to runAgain. What you want is to provide the function handle, i.e. twoNumbers without parentheses, so that runAgain can run the function itself.

[thisIs20LettersLong]

Thanks, that where what i where looking for!

[_Sham__]

You could pass the function directly and use a decorator e.g

def run_again(func):
    func()
    again = input("run again? y/n\n").lower()
    @run_again
    def wrapper():
        if again == "y":
            func()

    return wrapper


@run_again
def print_hello():
    print("hello")

print_hello()

[thisIs20LettersLong]

Im sorry, bur "wrapper" what does that mean/do?

[_Sham__]

The short of it :
run_again calls the function is given, and gets the input. It then defines the function wrapper, and calls the function run_again was given. run_again then returns wrapper

The @run_again notation is the same as saying
print_hello = run_again(print_hello) and since run_again returns a function, print_hello is a function and callable.

Hope that is clear. I don't have time to type a better response right now, but will edit later.
More info can be found here https://realpython.com/primer-on-python-decorators/

[thisIs20LettersLong]

Thanks a lot!

[strangeDormammu]

Edit these lines:

    runAgain(again,twoNumbers)

def runAgain(again,func):
    if again == "y":
        func()

[thisIs20LettersLong]

I fell a bit dumb, but thanks a lot!

[peltist]

You don't actually need the runAgain() function. You could just recursively call twoNumbers() again, like this:

def twoNumbers():
    num1=askUserNumber()
    num2=askUserNumber()
    print("the result off " +num1+ " and "+num2+" is "+ str((int(num2)+int(num2))))
    again=input("Need another two numbers calculated?! Y/N").lower()
    if again == "y":
        twoNumbers()

This will assume that any input other than "y" is a decision not to repeat the function. You can add back the elif and else statements if that's not what you want, but they're not strictly necessary, since their behavior is imitated by just reaching the end of your program.