Python: None value when returning from function

Question

I’m writing a program that stores 3 players and their scores in a list and then prints them out at the end. Simple stuff really, however I’m trying to call the value for the player score from a function called playerscore() which prevents you from entering a score >5.

this works fine when you run through it with the correct value, but if you input an incorrect value > 5 then it begins the playerscore function again and allows for a new value to be entered but returns “None”

teamlist = []

def playercreator():
    counter=0
    while counter < 3:
        name = playername()
        score = playerscore()
        print(score) #check - this one goes wrong when returned after the if/else in playerscore()
        teamlist.append(name+" "+str(score))
        counter = counter + 1

def playername():
    name=input("What name do you want for your player?n")
    return (name)

def playerscore():
    global teamtotal
    score=input("input score?n")
    print(score) #check
    if int(score)>5:
        print("Your attack score must be between 0 and 5")
        print(score) #check
        playerscore()
    else:
        return int(score)

playercreator()

for x in teamlist:
    print(x)

for example, these are the inputs and outputs:

What name do you want for your player?
p1
input score?
3
What name do you want for your player?
p2
input score?
6
Your attack score must be between 0 and 5
input score?
5
What name do you want for your player?
p3
input score?
2

p1 3
p2 None
p3 2

I feel like there’s something obvious that i’m missing. Can anyone point me in the right direction?

Asked By: mjolnir

||

Source

Answer 1

You are missing a return statement in the if block (when the score is greater than 5):

def playerscore():
    global teamtotal
    score=input("input score?n")
    if int(score)>5:
        print("Your attack score must be between 0 and 5")        
        return playerscore()
    else:
        return int(score)

Output:

What name do you want for your player?
shovon
input score?
2
2
What name do you want for your player?
sorida
input score?
23
Your attack score must be between 0 and 5
input score?
43
Your attack score must be between 0 and 5
input score?
234
Your attack score must be between 0 and 5
input score?
1
1
What name do you want for your player?
shody
input score?
2
2
shovon 2
sorida 1
shody 2

From official documentation:

In fact, even functions without a return statement do return a value, albeit a rather boring one. This value is called None (it’s a built-in name).

Answered By: arsho

Answer 2

When you are doing this:

if int(score)>5:
    playerscore()

you call playerscore function without return statement. This produces None value.

Answered By: py_dude

Answer 3

When function doesn’t return anything, value will be None.

So you should check your code for the case where score is larger than 5. (Compare it to the case where score is not larger than five.)

Answered By: ypcs

Answer 4

The type of recursion you’re trying to do with your code will work with a small correction on your code… which follows:

def playerscore():
global teamtotal
score=input("input score?n")
print(score) #check
if int(score)>5:
    print("Your attack score must be between 0 and 5")
    print(score) #check
    return playerscore()
else:
    return int(score)

You can notice that this time, we returned playerscore(). As it seems like you’re learning the basics, I’d like to propose a slightly different approach, as you’ll get a ValueError exception if the player types a string (some letters) instead of a number. You can keep using your recursive function in the exception catch, and use a while loop to make the player to keep the number within your desired range. Here follows my suggestion to prevent the ValueError exception:

def playerscore():
global teamtotal
score=input("input score?n")
try:
    while int(score) < 0 or int(score) > 5:
        print("Your attack score must be between 0 and 5")
        print(score)  # check
        score = input("input score?n")
except ValueError:
    print("Your attack score must be A NUMBER between 0 and 5")
    return playerscore()
return int(score)

I hope that helps. Regards.

Answered By: Marco Gomez

Python: None value when returning from function

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