[Python-Dev] Purpose of Doctests [Was: Best practices for Enum]

[Nick Coghlan]

On Mon, May 20, 2013 at 10:14 AM, Antoine Pitrou <solipsis at pitrou.net> wrote:
> On Sun, 19 May 2013 20:04:03 -0400
> Ned Batchelder <ned at nedbatchelder.com> wrote:
>> On 5/19/2013 7:22 PM, Mark Janssen wrote:
>> > On Sun, May 19, 2013 at 1:13 PM, Tres Seaver <tseaver at palladion.com> wrote:
>> >> -----BEGIN PGP SIGNED MESSAGE-----
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>> >> On 05/19/2013 10:48 AM, Guido van Rossum wrote:
>> >>> Anyway, if you're doing arithmetic on enums you're doing it wrong.
>> >> Hmm, bitwise operations, even?
>> > I think it's rather pointless to do bitwise operations on python
>> > enums.  We're not that close to the machine.
>>
>> It makes sense if the enums represent bit-oriented values that will be
>> used close to the machine.  Python is used in many disciplines.
>
> Then it's up to the library writer to not use enums in that case.
> (assuming the performance of bitwise operations is critical here, which
> I doubt)

This is the point I was trying to make: once you use IntEnum (as you
would in any case where you need bitwise operators), Enum gets out of
the way for everything other than __str__, __repr__, and one other
slot (that escapes me for the moment...).

The metaclass does extra work at definition time so there shouldn't be
any runtime overhead - the slots should be inherited directly from the
non-Enum parent.

Cheers,
Nick.

--
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia