Eric, I've some questions about BOOST_FOREACH (which is pretty cool, BTW). 1. Is it possible to use typeof on gcc, to avoid any possible overhead? While you've posted some results which show that gcc generally can optimise it very well, I'd like to be 100% sure). Something like: #define FOR_EACH(var, container) \ for(typeof(container.begin()) _for_each_i = container.begin(),\ _for_each_e = container.end();\ _for_each_i != _for_each_e; ++_for_each_i)\ if(bool _for_each_continue = false) {}\ else\ for(var = *_for_each_i; !_for_each_continue; _for_each_continue=true) which works perfectly for me. 2. Any chance that BOOST_FOREACH((pair<int, int> p), container) will work? I don't know how to make it work without require paranthethis in all cases, but maybe there's a smart trick. 3. Is it possible that you place this to sandbox, for easier access? - Volodya