This library provides three Singleton templates that share an identical interface :

- boost::singleton : can be used to create Singletons with synchronized initialization. If further synchronization is required it has to be implemented by the user.

- boost::mutexed_singleton : additionally ensures that concurrent access to the instance is mutually exclusive. In other words, only one thread can access the instance at a given time.

- boost::thread_specific_singleton : instances exist once per thread.

Tobias Schwinger

http://torjo.com/tobias/

What to include in Review Comments
==================================

Your comments may be brief or lengthy, but basically the Review Manager
needs your evaluation of the library. If you identify problems along
the way, please note if they are minor, serious, or showstoppers.

Here are some questions you might want to answer in your review:

* What is your evaluation of the design?
* What is your evaluation of the implementation?
* What is your evaluation of the documentation?
* What is your evaluation of the potential usefulness of the library?
* Did you try to use the library? With what compiler?
   Did you have any problems?
* How much effort did you put into your evaluation?
   A glance? A quick reading? In-depth study?
* Are you knowledgeable about the problem domain?

And finally, every review should answer this question:

* Do you think the library should be accepted as a Boost library?
   Be sure to say this explicitly so that your other comments
   don't obscure your overall opinion.

-- 
http://John.Torjo.com -- C++ expert
... call me only if you want things done right