...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::log::sources::swap
// In header: <boost/log/sources/threading_models.hpp> template<typename MutexT> void swap(multi_thread_model< MutexT > &, multi_thread_model< MutexT > &);