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[Python-Dev] PEP 435 - reference implementation discussion

Ethan Furman ethan at stoneleaf.us
Sun May 5 08:17:19 CEST 2013 
On 05/04/2013 10:59 PM, Ethan Furman wrote:
> On 05/04/2013 08:50 PM, Tim Delaney wrote:
>>
>> Think I've come up with a system that works for my auto-numbering case without knowing the internals of enum_type. Patch
>> passes all existing test cases. The patch does two things:
>>

[snip]

>> 2. Instead of directly setting the _name and _value of the enum_item, it lets the Enum class do it via Enum.__init__().
>> Subclasses can override this. This gives Enums a 2-phase construction just like other classes.
>
> Not sure I care for this.  Enums are, at least in theory, immutable objects, and immutable objects don't call __init__.

Okay, still thinking about `value`, but as far as `name` goes, it should not be passed -- it must be the same as it was 
in the class definition or we could end up with something like:

--> class AreYouKiddingMe(WierdEnum):
...     who = 1
...     what = 2
...     when = 3
...     where = 4
...     why = 5

--> list(AreYouKiddingMe)
[
   <AreYouKiddingMe.him: 1>,
   <AreYouKiddingMe.that: 2>,
   <AreYouKiddingMe.now: 3>,
   <AreYouKiddingMe.here: 4>,
   <AreYouKiddingMe.because: 5>,
]

and that's assuming we made more changes to support such insane behavior; otherwise it would just break.

So no passing of `name`, it gets set in the metaclass.

--
~Ethan~
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