singleton objects with decorators

[Fredrik Lundh]

Uwe Mayer wrote:

>> It strikes me that I've never wanted or needed a singleton object.
>> Would you mind sharing your use case?  I'm just curious.
>
> I am using a class to manage configuration settings in an application. This
> object should only existe once so that when the user
> changes a setting through a configuration dialog the change imminent in all
> locations where access to config settings are needed.

So use a module-level object, and be done with it.

Or if you're using an application object (you should), just add a config object
to the application object (app.config.param = ...).

Or use a module to hold the configuration data (import config; config.param = ...);
serializing to and from module variables work really well in Python.

> I was using a factory function bevore, but since I am starting to use Python
> 2.4 and I remembered having read about a singleton-decorator I went to look
> deeper into the possibilities.

I'm sure your users would love you even more if you spend that time and
energy adding stuff to the application... ;-)

</F>