Struct template subtract_typeof_helper<quantity< unit< Dim, System >, X >, quantity< unit< Dim, System >, Y >>

boost::units::subtract_typeof_helper<quantity< unit< Dim, System >, X >, quantity< unit< Dim, System >, Y >>

Synopsis

// In header: <boost/units/quantity.hpp>

template<typename Dim, typename System, typename X, typename Y> 
struct subtract_typeof_helper<quantity< unit< Dim, System >, X >, quantity< unit< Dim, System >, Y >> {
  // types
  typedef subtract_typeof_helper< X, Y >::type value_type;
  typedef unit< Dim, System >                  unit_type; 
  typedef quantity< unit_type, value_type >    type;      
};