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On Fri, 12 Apr 2013 15:33:02 -0400, Barry Warsaw <barry@python.org> wrote:

> On Apr 12, 2013, at 11:21 AM, Russell E. Owen wrote:

>

> >I, too, would strongly prefer to see ordering within an enum. I use

> >home-made enums heavily in my code and find ordering comparisons useful

> >there.

>

> This was all hashed out in gory detail on python-ideas. �I feel strongly that

> base EnumValues should be unordered, especially because the underlying values

> can be of any type. �What would you expect to happen in this case:

>

> � � class X(Enum):

> � � � � a = 1

> � � � � b = 'hi'

>

> � � if X.a < myvalue < X.b:

> � � � � # whaa?

>

> I think for most use cases, IntEnums will fit the bill for those who want

> ordered comparisons, and it's also easy to subclass EnumValues to specialize

> the behavior (in fact, this is how IntEnums are implemented).

>

> So if you really want ordered-comparisons-with-untyped-enum-values, you can

> have them. :)

You are right, the problem of comparison of disparate types makes ordering
a non-starter. �But by the same token that means you are going to have to
be consistent and give up on having a sorted iteration and a stable repr:

\>>> import enum
\>>> class Foo(enum.Enum):
... � �aa = 1
... � �bb = 2
... � �cc = 'hi'
\>>> Foo

Traceback (most recent call last):
� File "", line 1, in

� File "./enum.py", line 103, in \_\_repr\_\_
� � for k in sorted(cls.\_enums)))

TypeError: unorderable types: str() < int()