Store invalid input in a Python list

Question

I know I can handle invalid inputs using the try: except ValueError:, but how can I store that input in a list or variable or whatever?

I want that when the user inputs text, the code tells "It is definitely not [text]" in some part of the code (as it is seen in the code below). But it is not working the way it is.

while True:
        try:
            while guessedNumber != realNumber:
                tries = tries + 1
                checkTries()
                guessedNumbers.append(guessedNumber)
                os.system("clear")
                print(pyfiglet.figlet_format("Try again!", font = "big"))
                print("The number is:")
                for x in guessedNumbers:
                    if x < realNumber:
                        print("Higher than " + str(x))
                    elif x > realNumber:
                        print("Lower than " + str(x))
                    elif type(guessedNumber) is not int:
                        print("Definitely not " + str(x)) # to solve this, maybe use another Try: except:.
                guessedNumber = int(input("The number is... "))
            if tries == 1:
                os.system("clear")
                print(pyfiglet.figlet_format("You won!", font = "big"))
                print("You got it in the first try! What a lucky person!")
            else:
                os.system("clear")
                print(pyfiglet.figlet_format("You won!", font = "big"))
                print("Way to go! You got it in " + str(tries) + " tries!")
                break
        except ValueError:
            guessedNumbers.append(guessedNumber)
    playAgain()

@MarioKhoury That (like happens in the list of my script) the input should be an integer, but if the user inputs a string, that's the invalid input. The console returns that error. — Manu1Volta, Mar 09 '21 at 15:20

Jacob Lee · Answer 1 · 2021-03-09T19:29:18.923

1

Whether the user input comes as command lines arguments, passed function/method values, or input returned by the input() function, you can just create a list and add the invalid input inside the except clause.

Command Line Arguments

try:
    ...
except ValueError:
    invalid_input.append(sys.argv)

Function Calls

def my_func(argument):
    try:
        ...
    except ValueError:
        invalid_input.append(argument)

Input() Function

user_input = input()
try:
    ...
except ValueError:
    invalid_input.append(user_input)

Note the scope which you define invalid_input in would be up to your choosing.

Edit 1

Since the variable in question is only 'valid' if it is an integer, then checking for that property is the only statement needed in the try clause.

guesses = []
while True:
    guess = input("Guess a number")
    try:
        guess = int(guess)
    except ValueError:
        print(f"Definitely not {guess}")
        guesses.append(guess)
        continue

edited Mar 09 '21 at 19:29

answered Mar 09 '21 at 15:18

Jacob Lee

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That didn't work. I edited the question and added part of the code in my script. Maybe that helps. – Manu1Volta Mar 09 '21 at 17:10
@Manu1Volta First of all, I would suggest reducing the amount of code in the `try` clause. With essentially the entire code snippet inside the `try` clause, it is extremely difficult to pinpoint exactly where the `ValueError` would be raised. Second of all, what do you mean by *"That didn't work"*? Unless you give an expected output, I cannot write code which "works". – Jacob Lee Mar 09 '21 at 18:04
Yes, you are totally right... I'm just starting, so thank you! The expected output would be that the invalid input is stored in the list guessedNumbers, so that when I print the output with all the numbers inputted and a detail about each one, for the ones that are invalid, print that "Definitely is not [input text]". Following the code might be easier to understand. – Manu1Volta Mar 09 '21 at 18:28

Store invalid input in a Python list

1 Answers1

Command Line Arguments

Function Calls

Input() Function

Edit 1