I'm kinda new to coding and I'd like to be able to stop the program and if possible throw up a custom error message from within a function
(as in:
def Rounded_square(lots of inputs):
radius = (calculation)
if radius < 0:
stop.program("The radius is negative")
)
You want to raise an exception
raise ValueError("radius should be positive")
import os
os.exit("The radius is negative") , the value inside the exit() function will be printed to stderr and the return code will be 1 (thanks to @peter-wood for that revelation)
and just before that you can just use print for the message
exit, Python converts it to a string, prints it to stderr, and exits with code 1. See sys.exit
You can throw exceptions using raise statement in python:
raise Exception('Message') # Exception: Message
It is also possible to create custom exceptions:
class MyException(Exception):
pass
raise MyException('Message') # MyException: Message
So you should use:
raise TypeError('The radius is negative')
You should read some tutorials, about exceptions: https://www.tutorialspoint.com/python/python_exceptions.htm
