[Python-Dev] PEP-435 reference implementation (original) (raw)

Barry Warsaw barry at python.org
Wed May 1 17:44:32 CEST 2013

On Apr 30, 2013, at 10:50 PM, Ethan Furman wrote:

The way I had subclassing working originally was for the subclass to create it's own versions of the superclass' enum items -- they weren't the same object, but they were equal:

--> class Color(Enum): ... red = 1 ... green = 2 ... blue = 3 --> class MoreColor(Color): ... cyan = 4 ... magenta = 5 ... yellow = 6 --> Color.red is MoreColor.red False --> Color.red == MoreColor.red True If you switched from is to == would this work for you?

Not really, because in practice you don't compare one enum against another explicitly. You have a value in a variable and you're comparing against a literal enum. So is is still the more natural spelling.

My point is, if you want enums to behave more class-like because you're using the class syntax, then you shouldn't explicitly break this one class-like behavior just to protect some users from themselves. There doesn't even seem to be an easy way to override the default behavior if you really wanted to do it.

-Barry

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