Python | Reraise the Last Exception and Issue Warning
Problem – Reraising the exception, that has been caught in the except block.
Didn't work Traceback (most recent call last): File "", line 1, in File "", line 3, in example ValueError: invalid literal for int() with base 10: 'N/A'
This problem typically arises when there is no need to take any action in response to an exception (e.g., logging, cleanup, etc.). A very common use might be in catch-all exception handlers.
Code #2 : Catching all exception handlers.
Problem 2 – To have a program issue warning messages (e.g., about deprecated features or usage problems).
Code #3: Using the
The arguments to
warn() are a warning message along with a warning class, which is typically one of the following:
UserWarning, DeprecationWarning, SyntaxWarning, RuntimeWarning, ResourceWarning, or FutureWarning.
The handling of warnings depends on how the interpreter is executed and other configuration.
Output when running Python with the
-W all option.
bash % python3 -W all example.py example.py:5: DeprecationWarning: logfile argument is deprecated warnings.warn('logfile argument is deprecated', DeprecationWarning)
Normally, warnings just produce output messages on standard error. To turn warnings into exceptions, use the
-W error option.
bash % python3 -W error example.py Traceback (most recent call last): File "example.py", line 10, in
func(2, 3, logfile ='log.txt') File "example.py", line 5, in func warnings.warn('logfile argument is deprecated', DeprecationWarning) DeprecationWarning: logfile argument is deprecated bash %