// 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) 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_HOMOGENEOUS_SYSTEM_HPP_INCLUDED #define BOOST_UNITS_HOMOGENEOUS_SYSTEM_HPP_INCLUDED #include <boost/mpl/bool.hpp> #include <boost/units/config.hpp> #include <boost/units/static_rational.hpp> #ifdef BOOST_UNITS_CHECK_HOMOGENEOUS_UNITS #include <boost/type_traits/is_same.hpp> #include <boost/mpl/not.hpp> #include <boost/units/detail/linear_algebra.hpp> #endif namespace boost { namespace units { /// A system that can uniquely represent any unit /// which can be composed from a linearly independent set /// of base units. It is safe to rebind a unit with /// such a system to different dimensions. /// /// Do not construct this template directly. Use /// make_system instead. template<class L> struct homogeneous_system { /// INTERNAL ONLY typedef L type; }; template<class T, class E> struct static_power; template<class T, class R> struct static_root; /// INTERNAL ONLY template<class L, long N, long D> struct static_power<homogeneous_system<L>, static_rational<N,D> > { typedef homogeneous_system<L> type; }; /// INTERNAL ONLY template<class L, long N, long D> struct static_root<homogeneous_system<L>, static_rational<N,D> > { typedef homogeneous_system<L> type; }; namespace detail { template<class System, class Dimensions> struct check_system; #ifdef BOOST_UNITS_CHECK_HOMOGENEOUS_UNITS template<class L, class Dimensions> struct check_system<homogeneous_system<L>, Dimensions> : boost::mpl::not_< boost::is_same< typename calculate_base_unit_exponents< L, Dimensions >::type, inconsistent > > {}; #else template<class L, class Dimensions> struct check_system<homogeneous_system<L>, Dimensions> : mpl::true_ {}; #endif } // namespace detail } // namespace units } // namespace boost #if BOOST_UNITS_HAS_BOOST_TYPEOF #include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP() BOOST_TYPEOF_REGISTER_TEMPLATE(boost::units::homogeneous_system, (class)) #endif #endif