[ZODB-Dev] __setstate__

[Neil Schemenauer]

On Wed, Mar 27, 2002 at 10:43:49PM +0100, Magnus Lyck? wrote:
> I have a number of classes that subclass Persistence.Persistent.
> 
> I want to upgrade attributes for some of them, and understand
> that I should do this in __setstate__.

Yes.

> Can someone give an example of how to do this?


    class MyObject(Persistent):
        ...

        def __setstate__(self, dict):
            self.__dict__.update(dict)
            <do other things with MyObject instance>

        ...


> Do I need to call __setstate__ of a base class (Persistence.Persistent)
> in my own __setstate__?

Not necessary.

> Should I do something about __getstate__ as well?

Nope.

> Are there any particular gotchas or better alternatives?

Changes that you make in the __setstate__ will not dirty the object.

  Neil