...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::xpressive::op::make_pair::result<This(First,Second)>
template<typename This, typename First, typename Second> struct result<This(First, Second)> { // types typedef std::pair< UNCVREF(First), UNCVREF(Second)> type; };