How to return another return?

Question

I'm looking to use functions within my Python program to make it cleaner and more efficient, Within my function I either return true or false depending on a user's selection. Though in the case they enter an incorrect / invalid response, I'd like to return a return that way asking more questions don't be asked.

Edit:

To be a bit more descriptive; I'd like to re-create this:

def askquestion(question):
    response = input(question, "Enter T or F")
    if response == "T":
        return True
    elif response == "F":
        return False
    else:
        return None 

def askmultiple():
    questionOne = askquestion("Do you fruits?")
    if questionOne == None:
        return # Exit the function, not asking more questions

    questionTwo = askquestion("Do you Apples?")
    if questionTwo == None:
        return # Exit the function, not asking more questions

I want to cut out checking afterwards if it is None and just return return.

Can you please show the code you have so far so we have an idea of what you are doing — Agent Lu, Jul 01 '19 at 23:01
"I'd like to return a return" this doesn't make sense. `return` is part of a statement, it is not an object, thus it cannot be returned. you might as well ask "how do I return an `if`" — juanpa.arrivillaga, Jul 01 '19 at 23:03
This sounds like you want what [Asking the user for input until they give a valid response](https://stackoverflow.com/q/23294658/364696) was asking for. Only reason I'm not immediately marking it a duplicate is that your question is too vague to be sure it's a duplicate. — ShadowRanger, Jul 01 '19 at 23:06

score 0 · Answer 1 · answered Jul 01 '19 at 23:04

When you don't create a return statement at the end of a function that is equal to a sole return and those two are equal to return None call.

So you may organize your code like:

if returned_value is None:
    # do something a
elif returned_value is False:
    # do something else
else:  # value is True
    # do something b

score 0 · Answer 2 · answered Jul 01 '19 at 23:04

0

You can try using a while loop to make sure that the user inputs a correct input. For example:

while not response.isdigit():
     response =  input("That was not a number try again")

In this case, while the user input, "response" is not a number the python console will keep asking for a response. For a basic template,

while not (what you want):
    (ask for input again)

I hope this helps you. :)

answered Jul 01 '19 at 23:04

Agent Lu

104
13

Did this answer your question? – Agent Lu Jul 03 '19 at 20:05

score 0 · Answer 3 · answered Jul 02 '19 at 01:46

Use an exception flow.

def ask_question(prompt):
    """Asks a question, translating 'T' to True and 'F' to False"""
    response = input(prompt)

    table = {'T': True, 'F': False}
    return table[response.upper()]  # this allows `t` and `f` as valid answers, too.

def ask_multiple():
    questions = [
        "Do you fruits?",
        "Do you apples?",
        # and etc....
    ]

    try:
        for prompt in questions:
            result = ask_question(prompt)
    except KeyError as e:
        pass  # this is what happens when the user enters an incorrect response

Since table[response.upper()] will raise a KeyError if response.upper() is neither 'T' nor 'F', you can catch it down below and use that flow to move you out of the loop.

Another option is to write a validator that forces the user to answer correctly.

def ask_question(prompt):
    while True:
        response = input(prompt)
        if response.upper() in ['T', 'F']:
            break
    return True if response.upper() == 'T' else False

Did this work for you please checkmark it if it did. Thanks! — Agent Lu, Jul 11 '19 at 23:22

How to return another return?

3 Answers3