As far as I can tell, making a class object iterable by using a metaclass works just fine:
from __future__ import print_function
class IterableCar(type):
def __iter__(cls):
return iter(cls.__name__)
class Car(object):
__metaclass__ = IterableCar
def __init__(self, name):
self.name = name
if __name__=='__main__':
car1 = Car('Mercedes')
car2 = Car('Toyota')
for cars in Car:
print (cars)
Results in:
mgilson$ python ~/sandbox/test.py
C
a
r
Here's an example where I actually track the cars generated:
from __future__ import print_function
import weakref
class IterableCar(type):
_cars = weakref.WeakSet()
def __iter__(cls):
return iter(cls._cars)
def add_car(cls, car):
cls._cars.add(car)
class Car(object):
__metaclass__ = IterableCar
def __init__(self, name):
self.__class__.add_car(self)
self.name = name
if __name__=='__main__':
car1 = Car('Mercedes')
car2 = Car('Toyota')
for cars in Car:
print (cars.name)
Note that if you're using python3.x, to use a metaclass you do:
class Car(metaclass=IterableCar):
...
Rather than:
class Car(object):
__metaclass__ = IterableCar
which likely explains the problem that you're experiencing.
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