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Python

Posted by omri golan
omri golan
Courses Plus Student 15,836 Points

python function returns a none value for no reason

def getUsername():
    username = raw_input("Enter Your Username: ")
    if not username[0].isalpha():
        print "wrong"
        getUsername()
    else:
        return username

this function return None if i run it more then once can anybody tell me why ?

1 Answer

Michael Hulet
Michael Hulet
47,913 Points
Michael Hulet
Michael Hulet
47,913 Points

I haven't explicitly tested, but it's likely because this is intended to be a recursive function, but you don't return the call when it's called from within itself. Instead, when called from inside itself, the innermost return value is discarded, and None is passed up and returned by the original invocation. You can fix it like this:

def getUsername():
    username = raw_input("Enter Your Username: ")
    if not username[0].isalpha():
        print "wrong"
        # You need to have a return statement here
        return getUsername()
    else:
        return username