[docs] Possible Documentation bug: Chapter 8. Errors and Exceptions

[Rahul Babtiwale]

Hello,

I was going through the chapter as per the below link :
https://docs.python.org/3/tutorial/errors.html#handling-exceptions

The code shown is as below:

class B(Exception):
    pass
class C(B):
    pass
class D(C):
    pass
for cls in [B, C, D]:
    try:
        raise cls()
    except D:
        print("D")
    except C:
        print("C")
    except B:
        print("B")

- Now as per the above code the statement written below confused me a little:


*"A class in an except
<https://docs.python.org/3/reference/compound_stmts.html#except>
clause is compatible with an exception if it is
the same class or a base class thereof (but not the other way around — an
except clause listing a derived class is not compatible with a base class)."*

- A class in the except clause is compatible with an exception if it
is the same class: I agree to this.

- However, the next part "or a base class thereof" confused me. Does
this mean that if it is a base class
(i.e a class which inherits from the exception class and is the base
class of all the other classes C & D) only then will it be compatible?

- Because if i reverse the order of the except clauses, the only
prints would be 'B','B' and 'B'.

I think this elaboration needs to be done.

I would request you to provide your insights on this.

Thanks and Regards,

Rahul
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