| // Boost.Units - A C++ library for zero-overhead dimensional analysis and |
| // unit/quantity manipulation and conversion |
| // |
| // Copyright (C) 2003-2008 Matthias Christian Schabel |
| // Copyright (C) 2007-2008 Steven Watanabe |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See |
| // accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| |
| #ifndef BOOST_UNITS_DETAIL_DIMENSIONLESS_UNIT_HPP |
| #define BOOST_UNITS_DETAIL_DIMENSIONLESS_UNIT_HPP |
| |
| #include <boost/mpl/bool.hpp> |
| #include <boost/units/units_fwd.hpp> |
| |
| namespace boost { |
| namespace units { |
| |
| template<class T> |
| struct heterogeneous_system; |
| |
| template<class T> |
| struct homogeneous_system; |
| |
| template<class T1, class T2, class Scale> |
| struct heterogeneous_system_impl; |
| |
| typedef boost::units::heterogeneous_system< |
| boost::units::heterogeneous_system_impl< |
| boost::units::dimensionless_type, |
| boost::units::dimensionless_type, |
| boost::units::dimensionless_type |
| > |
| > heterogeneous_dimensionless_system; |
| |
| namespace detail { |
| |
| template<class System> |
| struct void_if_dimensionless { |
| typedef int type; |
| }; |
| |
| template<class T> |
| struct void_if_dimensionless<boost::units::homogeneous_system<T> > { |
| typedef void type; |
| }; |
| |
| template<> |
| struct void_if_dimensionless<heterogeneous_dimensionless_system> { |
| typedef void type; |
| }; |
| |
| template<class System, class Test = void> |
| struct void_if_heterogeneous { |
| typedef void type; |
| }; |
| |
| template<class System> |
| struct void_if_heterogeneous<System, typename void_if_dimensionless<System>::type> { |
| typedef int type; |
| }; |
| |
| template<class System, class Enable=void> |
| struct is_dimensionless_system : mpl::false_ {}; |
| |
| template<class System> |
| struct is_dimensionless_system<System, typename void_if_dimensionless<System>::type> : mpl::true_ {}; |
| |
| #define BOOST_UNITS_DIMENSIONLESS_UNIT(T)\ |
| boost::units::unit<\ |
| boost::units::dimensionless_type,\ |
| T,\ |
| typename ::boost::units::detail::void_if_dimensionless<T>::type\ |
| > |
| |
| #define BOOST_UNITS_HETEROGENEOUS_DIMENSIONLESS_UNIT(T)\ |
| boost::units::unit<\ |
| boost::units::dimensionless_type,\ |
| T,\ |
| typename ::boost::units::detail::void_if_heterogeneous<T>::type\ |
| > |
| |
| } |
| } |
| } |
| |
| #endif |