replacing __dict__ with an OrderedDict

alex23 wuwei23 at
Sun Jan 8 23:58:25 EST 2012

On Jan 7, 2:06 am, Ian Kelly < at> wrote:
> <ulrich.eckha... at> wrote:
> > Nonetheless, I'm still wondering if I could somehow replace the dict with an
> > OrderedDict.
> In Python 3, yes.  This is pretty much the entire use case for the new
> __prepare__ method of metaclasses.  See the "OrderedClass" example[...]

This isn't accurate. The OrderedClass example uses an OrderedDict to
remember the method creation order:

	def __new__(cls, name, bases, classdict):
		result = type.__new__(cls, name, bases, dict(classdict))
		result.members = tuple(classdict)
		return result

The instantiated objects __dict__ will still be a regularly
dictionary, while the assignment order is stored in the class
attribute .members.

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