...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::unit_test::bt_iterator_traits
// In header: <boost/test/utils/is_forward_iterable.hpp> template<typename T, bool is_forward_iterable = is_forward_iterable<T>::value> struct bt_iterator_traits { };