...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::base_from_member
// In header: <boost/utility/base_from_member.hpp> template<typename MemberType, int UniqueID = 0> class base_from_member { public: // protected member functions template<typename ... T, typename EnableIf = unspecified> explicit base_from_member(T &&...) noexcept(BOOST_NOEXCEPT_EXPR(::new((void *) 0) MemberType(static_cast< T && >(x)...))); };