What about removing the using-declaration, "using std::swap;", and adding an extra function, boost_swap_impl::swap<T>? Which would directly call std::swap, as follows:
namespace boost_swap_impl { template<class T> void swap(T& left, T& right) { std::swap(left,right); } }
Hmmm... not such a good idea of mine! Doing so would lead to ambiguity when the type T would /not/ have its own swap overload, while it would have the std namespace as an associated namespace. For example, when T would be a pointer-to-std::string or an std::time_base::dateorder enum. I wish this boost_swap_impl::swap could have been a little less "specialized"! (But still, it would need to be more specialized than boost::swap itself!) Anyway, I think we should add unit tests for std types! Kind regards, Niels