Defining Magic Methods On Classes

I would like to define a single object that can be iterated over without having to create a class and then an instance. Something like this: class Thing(object): stuff = ['foo'

Solution 1:

What Ashwini correctly suggested in his comment is the following. This works in Python 2.

classThingType(type):
    __stuff__ = ["foo", "bar", "baz"]

    @classmethoddef__iter__(cls):
        returniter(cls.__stuff__)

classThing(object):
    __metaclass__ = ThingType

for thing in Thing:
    print thing

And this works in Python 3:

classThingType(type):
    __stuff__ = ["foo", "bar", "baz"]

    @classmethoddef__iter__(cls):
        returniter(cls.__stuff__)

classThing(object, metaclass=ThingType):
    passfor thing in Thing:
    print(thing)

Solution 2:

Does Thing actually need to be a type? You could make it an object that has type-like callable behavior, which would probably be simpler:

classRealThing(object):
  passclassThingFactory(object):
  def__iter__(self):
    returniter(["foo", "bar", "baz"])

  def__call__(self):
    return RealThing()

Thing = ThingFactory()