Python · Errors and files

raise

Raises an exception. Re-raise with a bare raise inside an except block to preserve the traceback.

pythonRunnable example python course

Syntax

raise ValueError("message")

Example

Open in the lab

def positive(n):
    if n <= 0:
        raise ValueError("must be positive")
    return n
try:
    positive(0)
except ValueError as error:
    print(error)

Learn this in the course

Reference pages are the quick answer. The course explains the why, shows the full example and ends with a challenge.

Open the course

raise

Example

More in this group

Learn this in the course