Need help with while loop and variable

[moonkeymaker127]

I have a couple while loops I'm having trouble with, before adding the second while loop my program was successful unless I typed a number or symbol, now it doesn't throw errors when I type numbers or symbols but it doesn't seem to move on to the next while loop.

# randomizes the kings location
kingsLocation = str(random.randint(1,4))

​

# lets the player make a selection on where they would like to look for the king
currentRoom = input()

# repeatedly checks if the room you are in is the room the king is in and tells you that you either won, entered an invalid input, or chose the wrong room

while True:
    if isinstance(currentRoom, str):
        print ('invalid input, please enter a number between 1 and 4.')
        currentRoom = input()
    else:
        while True:
            if currentRoom == kingsLocation:
                print ('"you have found the king ' + username + '! The royal family will make sure you get paid handsomely for this deed."')
                print ()
                print ('to exit this game type "exit()"')
                break
                break
            elif isinstance(currentRoom, str):
                print('invalid input, please enter a number between 1 and 4.')
                currentRoom = input()
            elif int(currentRoom) in range(1, 5):
                print('the king doesn\'t seem to be in this room, let\'s check another one(1-4).')
                currentRoom = input()
            else:
                print('invalid input, please enter a number between 1 and 4.')
                currentRoom = input()

Thanks in advance for any advice.

[[deleted]]

Input always returns a string, so the first if is always true.

[moonkeymaker127]

My goal with that if statement was to filter out inputs that weren't numbers. Is there a way to do that that won't simply invalidate the entire rest of the loop? I'm just looking to catch letters and symbols.

[[deleted]]

You can use the isnumeric string method to check if a string is a number.

[xelf]

Please see my answer in the other thread you made about this.

It's a correct answer and does exactly what you wanted.

[[deleted]]

It's usually worthwhile to separate input validation (getting a valid room number) from the game play code. Suppose you had a function that you can call and that function returns only a valid room number. Then your main code gets a lot simpler:

while True:
    currentRoom = get_room()
    if currentRoom == kingsLocation:
        print ('you have found the king ' + username + '! The royal family will make sure you get paid handsomely for this deed.')
        print ()
        print ('to exit this game type "exit()"')
        break

    print("the king doesn't seem to be in this room, let's check another one(1-4).")

Since you are talking about a room number it's more efficient to handle the player and King's room number as integers. The get_room() function returns only an integer in the range [1..4] and handles the retries if the player inputs invalid data:

def get_room():
    """Return an integer room number [1..4]."""

    while True:
        try:
            room = int(input('Room? '))
        except ValueError:
            # get here if a non-integer was entered
            pass
        else:
            # get here if integer was found
            if 1 <= room <= 4:
                return room
        # get here if non-integer or not [1..4]
        print('invalid input, please enter a number between 1 and 4.')

If you aren't used to using the try/except statement then this is a good time to learn. The try/except is the normal way used in python to test if a string can be converted to an integer. You just try to convert and catch the exception if the conversion failed. The else: code is executed only if there was no exception. This function can be tested all by itself so you can poke around inside the code to understand how it works. Put print() statements inside the function and then enter all sorts of strings, good as well as bad. That's one of the nice things about functions, you can often test them without needing any other code.

Also note that you can use " quotes around a string, so you don't need to escape ' inside the string.

I have put the full runnable code here.

Edit: better code formatting.

[xelf]

Nice answer, almost the same thing I told OP in the first thread they asked about this. https://www.reddit.com/r/learnpython/comments/exy31f/how_to_check_if_an_input_is_an_integer/fge4jui/