How to use "raise" keyword in Python [duplicate] How to use "raise" keyword in Python [duplicate] python python

How to use "raise" keyword in Python [duplicate]


It has 2 purposes.

yentup has given the first one.

It's used for raising your own errors.

if something:    raise Exception('My error!')

The second is to reraise the current exception in an exception handler, so that it can be handled further up the call stack.

try:  generate_exception()except SomeException as e:  if not can_handle(e):    raise  handle_exception(e)


It's used for raising errors.

if something:    raise Exception('My error!')

Some examples here


raise without any arguments is a special use of python syntax. It means get the exception and re-raise it. If this usage it could have been called reraise.

    raise

From The Python Language Reference:

If no expressions are present, raise re-raises the last exception that was active in the current scope.

If raise is used alone without any argument is strictly used for reraise-ing. If done in the situation that is not at a reraise of another exception, the following error is shown:RuntimeError: No active exception to reraise


matomo