Is the 'pass' statement necessary for custom assertions?

Question

Consider:

class MyCleanUpError(Exception):
    """Error raised during teardown."""
    pass

versus:

class MyCleanUpError(Exception):
    """Error raised during teardown."""

I've seen the class declared with and with out the pass statement. Which is appropriate?

The pass statement would be needed if you did not have the doc string. — Stephen Rauch, Apr 18 '18 at 00:59
Possible duplicate of [How to use the pass statement in Python](https://stackoverflow.com/questions/13886168/how-to-use-the-pass-statement-in-python) — Stephen Rauch, Apr 18 '18 at 01:00

score 2 · Answer 1 · answered Apr 18 '18 at 01:01

the pass statement simply does nothing. since """whatever this string is""" is a valid object, it is fine without the pass statement. you can also use ... (Ellipsis) in python 3 +, or 1, or None or whatever you want to do. you just cant do this:

class MyCleanUpError(Exception):

# other code

or else you will get an IndentationError. you also cant use a comment as a placeholder. it is generally appropriate to use pass or ..., because they make more sense than 1 or just having a docstring.

Is the 'pass' statement necessary for custom assertions?

1 Answers1