...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::intrusive::hash_key_equal
// In header: <boost/intrusive/hashtable.hpp> template<typename T, typename VoidOrKeyOfValue, typename VoidOrKeyEqual> struct hash_key_equal : public boost::intrusive::get_equal_to< VoidOrKeyEqual, hash_key_types_base< T, VoidOrKeyOfValue >::key_type > { };