...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::is_dimensionless_unit — check that a type is a dimensionless unit
// In header: <boost/units/is_dimensionless_unit.hpp> template<typename T> struct is_dimensionless_unit : public boost::units::is_unit_of_dimension< T, boost::units::dimensionless_type > { };