...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::top::result<This(Sequence)>
// In header: <boost/xpressive/regex_actions.hpp> template<typename This, typename Sequence> struct result<This(Sequence)> { // types typedef remove_reference< Sequence >::type sequence_type; typedef mpl::if_c< is_const< sequence_type >::value, typename sequence_type::value_type const &, typename sequence_type::value_type & >::type type; };