...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::units::quantity< BOOST_UNITS_DIMENSIONLESS_UNIT(S), Y >
// In header: <boost/units/cmath.hpp> quantity< BOOST_UNITS_DIMENSIONLESS_UNIT(S), Y >;