Hello, This is just a notification about this thread: http://thread.gmane.org/gmane.comp.lib.boost.devel/259433 It is exactly the problem I predicted a year ago: http://thread.gmane.org/gmane.comp.lang.c++.isocpp.features/17/focus=24 In case you want to discuss it or take any action in response in SD-6. Thanks, Steve.