Nested Properties

nestprop.py

class Outer(object):
    """
    >>> Outer.class_attr
    'ca0'
    >>> outer = Outer("ia0", "ia1", "ia2")
    >>> outer.inst_attr
    'ia0'
    >>> outer.inner
    <__main__.Outer.Inner object at 0x...>
    >>> outer.inner.class_attr
    'ca1'
    >>> outer.inner.outer
    <__main__.Outer object at 0x...>
    >>> outer.inner.inst_attr
    'ia1'
    >>> outer.inner.enclosed_class_attr
    'ca0'
    >>> outer.inner.enclosed_inst_attr
    'ia0'
    >>> outer.inner.inner
    <__main__.Outer.Inner.Inner object at 0x...>
    >>> outer.inner.inner.class_attr
    'ca2'
    >>> outer.inner.inner.outer
    <__main__.Outer.Inner object at 0x...>
    >>> outer.inner.inner.inst_attr
    'ia2'
    >>> outer.inner.inner.enclosed_class_attr
    'ca1'
    >>> outer.inner.inner.enclosed_inst_attr
    'ia1'
    >>> outer.inner.inner.twice_enclosed_class_attr
    'ca0'
    >>> outer.inner.inner.twice_enclosed_inst_attr
    'ia0'
    """

    class_attr = "ca0"

    def __init__(self, ia0=None, ia1=None, ia2=None):

        self.inst_attr = ia0
        self._inner = self.Inner(self, ia1=ia1, ia2=ia2)

    @property
    def inner(self):
        return self._inner

    class Inner(object):

        class_attr = "ca1"

        def __init__(self, outer, ia1=None, ia2=None):

            self.outer = outer
            self.inst_attr = ia1
            self.enclosed_class_attr = outer.class_attr
            self.enclosed_inst_attr = outer.inst_attr
            self._inner = self.Inner(self, ia2=ia2)

        @property
        def inner(self):
            return self._inner

        class Inner(object):

            class_attr = "ca2"

            def __init__(self, outer, ia2=None):

                self.outer = outer
                self.inst_attr = ia2
                self.enclosed_class_attr = outer.class_attr
                self.enclosed_inst_attr = outer.inst_attr
                self.twice_enclosed_class_attr = outer.outer.class_attr
                self.twice_enclosed_inst_attr = outer.outer.inst_attr


if __name__ == "__main__":
    import doctest
    doctest.testmod(optionflags=doctest.ELLIPSIS)