Javascript style dot notation for dictionary keys unpythonic?

This is a simpler version of your DictObj class:

class DictObj(object):
    def __getattr__(self, attr):
        return self.__dict__.get(attr)

>>> d = DictObj()
>>> d.something = 'one'
>>> print d.something
one
>>> print d.somethingelse
None
>>> 

Your DictObj example is actually quite common. Object-style dot-notation access can be a win if you are dealing with ‘things that resemble objects’, ie. they have fixed property names containing only characters valid in Python identifiers. Stuff like database rows or form submissions can be usefully stored in this kind of object, making code a little more readable without the excess of ['item access'].

The implementation is a bit limited - you don't get the nice constructor syntax of dict, len(), comparisons, 'in', iteration or nice reprs. You can of course implement those things yourself, but in the new-style-classes world you can get them for free by simply subclassing dict:

class AttrDict(dict):
    __getattr__ = dict.__getitem__
    __setattr__ = dict.__setitem__
    __delattr__ = dict.__delitem__

To get the default-to-None behaviour, simply subclass Python 2.5's collections.defaultdict class instead of dict.

With regards to the DictObj, would the following work for you? A blank class will allow you to arbitrarily add to or replace stuff in a container object.

class Container(object):
    pass

>>> myContainer = Container()
>>> myContainer.spam = "in a can"
>>> myContainer.eggs = "in a shell"

If you want to not throw an AttributeError when there is no attribute, what do you think about the following? Personally, I'd prefer to use a dict for clarity, or to use a try/except clause.

class QuietContainer(object):
    def __getattr__(self, attribute):
        try:
            return object.__getattr__(self,attribute)
        except AttributeError:
            return None

>>> cont = QuietContainer()
>>> print cont.me
None

Right?