1 // Boost.Units - A C++ library for zero-overhead dimensional analysis and 2 // unit/quantity manipulation and conversion 3 // 4 // Copyright (C) 2003-2008 Matthias Christian Schabel 5 // Copyright (C) 2008 Steven Watanabe 6 // 7 // Distributed under the Boost Software License, Version 1.0. (See 8 // accompanying file LICENSE_1_0.txt or copy at 9 // http://www.boost.org/LICENSE_1_0.txt) 10 11 #ifndef BOOST_UNITS_IS_DIMENSIONLESS_HPP 12 #define BOOST_UNITS_IS_DIMENSIONLESS_HPP 13 14 /// 15 /// \file 16 /// \brief Check if a unit or quantity is dimensionless. 17 /// 18 19 #include <boost/mpl/bool.hpp> 20 #include <boost/units/units_fwd.hpp> 21 22 namespace boost { 23 24 namespace units { 25 26 template<class T> 27 struct is_dimensionless : 28 public mpl::false_ 29 { }; 30 31 /// Check if a unit is dimensionless. 32 template<class System> 33 struct is_dimensionless< unit<dimensionless_type,System> > : 34 public mpl::true_ 35 { }; 36 37 /// Check if a quantity is dimensionless. 38 template<class Unit,class Y> 39 struct is_dimensionless< quantity<Unit,Y> > : 40 public is_dimensionless<Unit> 41 { }; 42 43 } // namespace units 44 45 } // namespace boost 46 47 #endif // BOOST_UNITS_IS_DIMENSIONLESS_HPP 48