Strange boolean value in Python Exception-CodePudding

Recently I came across a strange part of code in one of the repositories I use for work. In this part, an exception is raised with a boolean value:

if current_run_row_count == 0:
        raise InconsistentData(
            "0 rows found", False,
        )

InconsistentData inherits from Exception class:

class InconsistentData(Exception):
    pass

I do not understand what this False corresponding to the exception raise does.

First my guess was that it is some marker whether this exception is actually a warning (I think I might have heard something like this). If it is True, then exception stops program execution, and if it is False, it does not stop it and acts as a warning. It could also be vice versa, but the idea is the same. However, I could not find any information about Exception arguments in Python documentation - for instance, here and here.

Secondly, I thought that maybe this False just does nothing and appears to be a part of the error message. I tested it with two different samples of code.

First one:

if 1 == 1:
    raise Exception("error", False)

print('Hello!')

Output:

Exception: ('error', False)

Second one:

if 1 == 1:
    raise Exception("error", True)

print('Hello!')

Output:

Exception: ('error', True)

So, in both code samples the exception is raised and stops program execution, and this boolean value seems to be a part of the error message. However, according to the code, I have no idea why would anyone include it in the error message. Along with InconsistentData, there are two other custom exceptions: CustomException and ValidationError, and when they are raised, they do not have any boolean values, only an error message represented with text.

CodePudding user response：

It is probably second option - "this False just does nothing and appears to be a part of the error message". I will accept @deceze answer:

It means whatever the author wants it to mean. It has no influence on the exception as such, as you have correctly identified. It's just additional data.