Question

for example:

obj1 = ClassName()
obj1.name = "name1"
obj2 = ClassName()
obj2.name = "name2"
obj3 = ClassName()
obj3.name = "name3"
obj4 = ClassName()
obj4.name = "name4"

and we have static variable that return number of objects:
ClassName.counter

How i can get obj1.name, obj2.name and other, but if objects count can be dynamic(using cycle for example) ?

PS: more good if you can say me how to do that in the python, but only design will be good also.

Answer 1

Well… it’s actually not recommended to do this type of staff, being a little incomprehensible and prone to bugs…however, you could do it this way:

class MyClass(object):
    names_list = []
    _name = None

    def get_name(self):
        return self._name
    def set_name(self, name):
        assert self._name is None
        self._name = name
        self.names_list.append(name)
    name = property(get_name, set_name)

obj1 = MyClass()
obj1.name = 'name1'

obj2 = MyClass()
obj2.name = 'name2'

print obj1.names_list
print len(obj1.names_list)

It works. It’s ugly. Using some external factory to handle it is probably much better. If you want to store links to existing instances, some array/dictionary with weakrefs would probably be a fine solution.