...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::accumulators::as_feature<tag::variance(immediate)>
// In header: <boost/accumulators/statistics/variance.hpp> struct as_feature<tag::variance(immediate)> { // types typedef tag::variance type; };