July 29, 2009
Correction re singletons
The source code link presented at the main post for my singleton mixin classes was bad until now. It pointed to an earlier version that didn't have thread safety or various other improvements. Sorry.
July 28, 2009
Even more singleton improvements
singletonmixin now deals with cases where you want to be able to include args in calls to S.getInstance() even after the initial instantiation.
July 27, 2009
More singleton improvements
Based on internal work and feedback appearing in comments on this blog, I've updated the Python singleton class I posted way back in 2004. That earlier post remains the place to get the code and place any further comments.
It now handles keyword arguments, and is threadsafe for singleton creation.