On 6 May 2013 08:00, Guido van Rossum <gu...@python.org> wrote: > On Sun, May 5, 2013 at 2:55 PM, Tim Delaney <timothy.c.dela...@gmail.com> > wrote: > > So long as I can get one of the requirements documented to implement an > > auto-number syntax I'll be happy enough with stdlib enums I think. > > Specifically what do you want the PEP to promise? >
It was mentioned in the other threads, but the requirement is either: 1. That the dictionary returned from <enum metaclass>.__prepare__ provide a way to obtain the enum instance names once it's been populated (e.g. once it's been passed as the classdict to __new__). The reference implementation provides a _enum_names list attribute. The enum names need to be available to a metaclass subclass before calling the base metaclass __new__. OR 2. A way for subclasses of Enum to modify the value before it's assigned to the actual enum - see the PEP 435 reference implementation - discussion thread where I modified the reference implementation to give enum instances 2-phase construction, passing the value to Enum.__init__. This way is more limited, as you need to use an appropriate mix-in type which puts certain constraints on the behaviour of the enum instances (e.g. they *have* to be int instances for auto-numbering). The implementation is also more complex, and as noted in that thread, __init__ might not be appropriate for an Enum. Tim Delaney
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