Subclassing dict

[marcux]

Hi all!
I want to make a subclass of dict and I have read about subclassing and the super method.
The problem that I do not get is how I override the following method:

dict[key] = value

This creates a new key with the specified value.
I want to override this to make some file writing and the call super, how do I do this?

Many thanks in advance!
Marcux

[Gribouillis]

You must overwrite the __setitem__ method

class mydict(dict):
    def __setitem__(self, key, value):
        doStuff()
        return dict.__setitem__(self, key, value)

[marcux]

Thanks Gribouillis!
That was exactly what I was looking for.
By the way...isn't:

dict.__setitem__(self, key, value)

The old style to call super class?
Aren't you supposed to use super, as in:

super(mydict, self).__setitem__(self, key, value)

Or have I got it all wrong with super classes?

Marcux

[Gribouillis]

Well, super has been around for some time now, but it's not very useful. Better call the parent class directly.

[marcux]

Thanks again!
The last question regarding dict.
How do I override when a user deletes an item with:

del d[key]

Second of all where can I find this info?
It is not specified in the sandard lib. doc.

Many thanks again!
Marcux

[Mathhax0r]

A quick google search of "python special class methods" pulled up this: http://diveintopython3.org/special-method-names.html

[Gribouillis]

It's also in the python documentation :)