preferring [] or () in list of error codes?

Ben Finney ben+python at
Mon Jun 8 23:43:08 EDT 2009

Steven D'Aprano <steven at> writes:

> In addition, using a tuple or a list in this context:
>     if e.message.code in (25401,25402,25408):
> is so idiomatic, that using a set in it's place would be distracting.

I think a list in that context is fine, and that's the idiom I see far
more often than a tuple.

> Rather that efficiently communicating the programmer's intention, it
> would raise in my mind the question "that's strange, why are they
> using a set there instead of a tuple?".

The fact that literal set syntax is a relative newcomer is the primary
reason for that, I'd wager.

 \       “If you are unable to leave your room, expose yourself in the |
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_o__)                                                                  |
Ben Finney

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