Don'T Inherit From Python Baseexception, Here'S Why.
Waylon Walker
Learning in Public @_WaylonWalker
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I ran into a PR this week where the author was inheriting what BaseException rather than exception. I made this example to illustrate the unintended side effects that it can have.
Try running these examples in a .py file for yourself and try to kill them
with control-c.
You cannot Keybard interrupt
Since things such as KeyboardInterrupt are created as an exception that
inherits from BaseException, if you except BaseException you can no longer
KeyboardInterrupt.
from time import sleep while True: try: sleep(30) except BaseException: # ❌ pass
except from Exception or higher
If you except from exception or something than inherits from it you will be better off, and avoid unintended side effects.
from time import sleep while True: try: sleep(30) except Exception: # ✅ pass
This goes with Custom Exceptions as well
When you make custom exceptions expect that users, or your team members will
want to catch them and try to handle them if they can. If you inherit from
BaseException you will put them in a similar situation when they use your
custom Exception.
class MyFancyException(BaseException): # ❌ ... class MyFancyException(Exception): # ✅ ...