How to change behavior of dict() for an instance

Question

So I\'m writing a class that extends a dictionary which right now uses a method \"dictify\" to transform itself into a dict. What I would like to do instead though is change it

Answer 1

edit: As ironchefpython pointed out in comments, this isn't actually doing what I thought it did, as in my example b[1] is still a RecursiveDict. This may still be useful, as you essentially get an object pretty similar Rob Cowie's answer, but it is built on defaultdict.

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You can get the behavior you want (or something very similar) by overriding __repr__, check this out:

class RecursiveDict(defaultdict):
    def __init__(self):
        super(RecursiveDict, self).__init__(RecursiveDict)

    def __repr__(self):
        return repr(dict(self))

>>> a = RecursiveDict()
>>> a[1][2][3] = 4
>>> a             # a looks like a normal dict since repr is overridden
{1: {2: {3: 4}}}
>>> type(a)

>>> b = dict(a)
>>> b             # dict(a) gives us a normal dictionary
{1: {2: {3: 4}}}
>>> b[5][6] = 7   # obviously this won't work anymore
Traceback (most recent call last):
  File "", line 1, in 
KeyError: 5
>>> type(b)

There may be a better way to get to a normal dictionary view of the defaultdict than dict(self) but I couldn't find one, comment if you know how.