// 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_DETAIL_HETEROGENEOUS_CONVERSION_HPP | |
#define BOOST_UNITS_DETAIL_HETEROGENEOUS_CONVERSION_HPP | |
#include <boost/mpl/minus.hpp> | |
#include <boost/mpl/times.hpp> | |
#include <boost/units/static_rational.hpp> | |
#include <boost/units/homogeneous_system.hpp> | |
#include <boost/units/detail/linear_algebra.hpp> | |
namespace boost { | |
namespace units { | |
namespace detail { | |
struct solve_end { | |
template<class Begin, class Y> | |
struct apply { | |
typedef dimensionless_type type; | |
}; | |
}; | |
struct no_solution {}; | |
template<class X1, class X2, class Next> | |
struct solve_normal { | |
template<class Begin, class Y> | |
struct apply { | |
typedef typename Begin::next next; | |
typedef list< | |
typename mpl::minus< | |
typename mpl::times<X1, Y>::type, | |
typename mpl::times<X2, typename Begin::item>::type | |
>::type, | |
typename Next::template apply<next, Y>::type | |
> type; | |
}; | |
}; | |
template<class Next> | |
struct solve_leading_zeroes { | |
template<class Begin> | |
struct apply { | |
typedef list< | |
typename Begin::item, | |
typename Next::template apply<typename Begin::next>::type | |
> type; | |
}; | |
typedef solve_leading_zeroes type; | |
}; | |
template<> | |
struct solve_leading_zeroes<no_solution> { | |
typedef no_solution type; | |
}; | |
template<class Next> | |
struct solve_first_non_zero { | |
template<class Begin> | |
struct apply { | |
typedef typename Next::template apply< | |
typename Begin::next, | |
typename Begin::item | |
>::type type; | |
}; | |
}; | |
template<class Next> | |
struct solve_internal_zero { | |
template<class Begin, class Y> | |
struct apply { | |
typedef list< | |
typename Begin::item, | |
typename Next::template apply<typename Begin::next, Y>::type | |
> type; | |
}; | |
}; | |
template<class T> | |
struct make_solve_list_internal_zero { | |
template<class Next, class X> | |
struct apply { | |
typedef solve_normal<T, X, Next> type; | |
}; | |
}; | |
template<> | |
struct make_solve_list_internal_zero<static_rational<0> > { | |
template<class Next, class X> | |
struct apply { | |
typedef solve_internal_zero<Next> type; | |
}; | |
}; | |
template<int N> | |
struct make_solve_list_normal { | |
template<class Begin, class X> | |
struct apply { | |
typedef typename make_solve_list_internal_zero< | |
typename Begin::item | |
>::template apply< | |
typename make_solve_list_normal<N-1>::template apply<typename Begin::next, X>::type, | |
X | |
>::type type; | |
}; | |
}; | |
template<> | |
struct make_solve_list_normal<0> { | |
template<class Begin, class X> | |
struct apply { | |
typedef solve_end type; | |
}; | |
}; | |
template<int N> | |
struct make_solve_list_leading_zeroes; | |
template<class T> | |
struct make_solve_list_first_non_zero { | |
template<class Begin, int N> | |
struct apply { | |
typedef solve_first_non_zero< | |
typename make_solve_list_normal<N-1>::template apply< | |
typename Begin::next, | |
typename Begin::item | |
>::type | |
> type; | |
}; | |
}; | |
template<> | |
struct make_solve_list_first_non_zero<static_rational<0> > { | |
template<class Begin, int N> | |
struct apply { | |
typedef typename solve_leading_zeroes< | |
typename make_solve_list_leading_zeroes<N-1>::template apply< | |
typename Begin::next | |
>::type | |
>::type type; | |
}; | |
}; | |
template<int N> | |
struct make_solve_list_leading_zeroes { | |
template<class Begin> | |
struct apply { | |
typedef typename make_solve_list_first_non_zero<typename Begin::item>::template apply<Begin, N>::type type; | |
}; | |
}; | |
template<> | |
struct make_solve_list_leading_zeroes<0> { | |
template<class Begin> | |
struct apply { | |
typedef no_solution type; | |
}; | |
}; | |
template<int N> | |
struct try_add_unit_impl { | |
template<class Begin, class L> | |
struct apply { | |
typedef typename try_add_unit_impl<N-1>::template apply<typename Begin::next, L>::type next; | |
typedef typename Begin::item::template apply<next>::type type; | |
BOOST_STATIC_ASSERT((next::size::value - 1 == type::size::value)); | |
}; | |
}; | |
template<> | |
struct try_add_unit_impl<0> { | |
template<class Begin, class L> | |
struct apply { | |
typedef L type; | |
}; | |
}; | |
template<int N> | |
struct make_homogeneous_system_impl; | |
template<class T, bool is_done> | |
struct make_homogeneous_system_func; | |
template<class T> | |
struct make_homogeneous_system_func<T, false> { | |
template<class Begin, class Current, class Units, class Dimensions, int N> | |
struct apply { | |
typedef typename make_homogeneous_system_impl<N-1>::template apply< | |
typename Begin::next, | |
list<T, Current>, | |
list<typename Begin::item, Units>, | |
Dimensions | |
>::type type; | |
}; | |
}; | |
template<class T> | |
struct make_homogeneous_system_func<T, true> { | |
template<class Begin, class Current, class Units, class Dimensions, int N> | |
struct apply { | |
typedef list<typename Begin::item, Units> type; | |
}; | |
}; | |
template<> | |
struct make_homogeneous_system_func<no_solution, false> { | |
template<class Begin, class Current, class Units, class Dimensions, int N> | |
struct apply { | |
typedef typename make_homogeneous_system_impl<N-1>::template apply< | |
typename Begin::next, | |
Current, | |
Units, | |
Dimensions | |
>::type type; | |
}; | |
}; | |
template<> | |
struct make_homogeneous_system_func<no_solution, true> { | |
template<class Begin, class Current, class Units, class Dimensions, int N> | |
struct apply { | |
typedef typename make_homogeneous_system_impl<N-1>::template apply< | |
typename Begin::next, | |
Current, | |
Units, | |
Dimensions | |
>::type type; | |
}; | |
}; | |
template<int N> | |
struct make_homogeneous_system_impl { | |
template<class Begin, class Current, class Units, class Dimensions> | |
struct apply { | |
typedef typename expand_dimensions<Dimensions::size::value>::template apply< | |
Dimensions, | |
typename Begin::item::dimension_type | |
>::type dimensions; | |
typedef typename try_add_unit_impl<Current::size::value>::template apply<Current, dimensions>::type new_element; | |
typedef typename make_solve_list_leading_zeroes<new_element::size::value>::template apply<new_element>::type new_func; | |
typedef typename make_homogeneous_system_func< | |
new_func, | |
((Current::size::value)+1) == (Dimensions::size::value) | |
>::template apply<Begin, Current, Units, Dimensions, N>::type type; | |
}; | |
}; | |
template<> | |
struct make_homogeneous_system_impl<0> { | |
template<class Begin, class Current, class Units, class Dimensions> | |
struct apply { | |
typedef Units type; | |
}; | |
}; | |
template<class Units> | |
struct make_homogeneous_system { | |
typedef typename find_base_dimensions<Units>::type base_dimensions; | |
typedef homogeneous_system< | |
typename insertion_sort< | |
typename make_homogeneous_system_impl< | |
Units::size::value | |
>::template apply< | |
Units, | |
dimensionless_type, | |
dimensionless_type, | |
base_dimensions | |
>::type | |
>::type | |
> type; | |
}; | |
template<int N> | |
struct extract_base_units { | |
template<class Begin, class T> | |
struct apply { | |
typedef list< | |
typename Begin::item::tag_type, | |
typename extract_base_units<N-1>::template apply<typename Begin::next, T>::type | |
> type; | |
}; | |
}; | |
template<> | |
struct extract_base_units<0> { | |
template<class Begin, class T> | |
struct apply { | |
typedef T type; | |
}; | |
}; | |
} | |
} | |
} | |
#endif |