Python cant get isdigit() work with len()-CodePudding

Ok ran into wall too much. Could use some help. Thank you

def code(text: str) -> str:
emp_str = ""

    for m in text:
        if m.isdigit():  # Picks the numbers from text.
            emp_str = emp_str   m
            if 0 < len(emp_str) < 11:
                return "Not enough numbers!"
            if len(emp_str) > 11:
                return "Too many numbers!"
    else:
        return emp_str

if __name__ == '__main__':
    
    print(code(""))
    print(code("123456789123456789"))"
    print(code("ID code is: 49403136526"))
    print(code("efs4  9   #4aw0h 3r 1a36g5j2!!6-"))

End result should be:

Not enough numbers!
Too many numbers!
49403136526
49403136526

But instead i get:


Not enough numbers!
Not enough numbers!
Not enough numbers!

It semi works if i change this part of the code len(emp_str) < 11: to if len(emp_str) < 0:

Result:


Too many numbers!
49403136526
49403136526

Edited what i ment was the results look like the first line print answer is missing i know that len("") is 0.

CodePudding user response：

Better to use re, I think. Like this:

import re

def code2(text: str):
    matches = re.findall("\\d", text)
    num_digits = len(matches) if matches else 0
    if 0 <= num_digits < 11:
        return "Not enough numbers!"
    if num_digits > 11:
        return "Too many numbers!"

    return "".join(matches)

CodePudding user response：

There are several things wrong: you return a message only when some character isdigit. First loop over the text and then assess the number of digits. Also don't forget to check for 0 in condition if 0 <= len(s) < 11. Try following code:

s = ''
for m in text:
    if m.isdigit():
        s  = m
if 0 <= len(s) < 11:
    return "Not enough numbers!"
elif len(s) >= 11:
    return "Too many numbers!"
return s

CodePudding user response：

I've never had much luck with isdigit(). I use a try/except statement to accomplish this

def code(text: str) -> str:
    emp_str = ""

    for m in text:
        try:
            int_buffer = int(m). # try to make string into an integer
            emp_str = emp_str   m
            if len(emp_str) > 11:
                return "Too many numbers!"
            if not len(emp_str):
                return "Not enough numbers!"
        except Value error:
            pass
    return emp_str

if __name__ == '__main__':

    print(code(""))
    print(code("123456789123456789"))"
    print(code("ID code is: 49403136526"))
    print(code("efs4  9   #4aw0h 3r 1a36g5j2!!6-"))