Chris@16: // Boost.Units - A C++ library for zero-overhead dimensional analysis and 
Chris@16: // unit/quantity manipulation and conversion
Chris@16: //
Chris@16: // Copyright (C) 2003-2008 Matthias Christian Schabel
Chris@16: // Copyright (C) 2008 Steven Watanabe
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_UNITS_DIMENSION_IMPL_HPP
Chris@16: #define BOOST_UNITS_DIMENSION_IMPL_HPP
Chris@16: 
Chris@16: #include <boost/mpl/begin_end.hpp>
Chris@16: #include <boost/mpl/deref.hpp>
Chris@16: #include <boost/mpl/if.hpp>
Chris@16: #include <boost/mpl/list.hpp>
Chris@16: #include <boost/mpl/next.hpp>
Chris@16: #include <boost/mpl/size.hpp>
Chris@16: #include <boost/mpl/less.hpp>
Chris@16: 
Chris@16: #include <boost/units/config.hpp>
Chris@16: #include <boost/units/dimensionless_type.hpp>
Chris@16: #include <boost/units/static_rational.hpp>
Chris@16: #include <boost/units/units_fwd.hpp>
Chris@16: #include <boost/units/detail/dimension_list.hpp>
Chris@16: #include <boost/units/detail/push_front_if.hpp>
Chris@16: #include <boost/units/detail/push_front_or_add.hpp>
Chris@16: 
Chris@16: /// \file 
Chris@16: /// \brief Core class and metaprogramming utilities for compile-time dimensional analysis.
Chris@16: 
Chris@16: namespace boost {
Chris@16: 
Chris@16: namespace units {
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: template<int N>
Chris@16: struct insertion_sort_dims_insert;
Chris@16: 
Chris@16: template<bool is_greater>
Chris@16: struct insertion_sort_dims_comparison_impl;
Chris@16: 
Chris@16: // have to recursively add the element to the next sequence.
Chris@16: template<>
Chris@16: struct insertion_sort_dims_comparison_impl<true> {
Chris@16:     template<class Begin, int N, class T>
Chris@16:     struct apply {
Chris@16:         typedef list<
Chris@16:             typename Begin::item,
Chris@16:             typename insertion_sort_dims_insert<N - 1>::template apply<
Chris@16:                 typename Begin::next,
Chris@16:                 T
Chris@16:             >::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: // either prepend the current element or join it to
Chris@16: // the first remaining element of the sequence.
Chris@16: template<>
Chris@16: struct insertion_sort_dims_comparison_impl<false> {
Chris@16:     template<class Begin, int N, class T>
Chris@16:     struct apply {
Chris@16:         typedef typename push_front_or_add<Begin, T>::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct insertion_sort_dims_insert {
Chris@16:     template<class Begin, class T>
Chris@16:     struct apply {
Chris@16:         typedef typename insertion_sort_dims_comparison_impl<mpl::less<typename Begin::item, T>::value>::template apply<
Chris@16:             Begin,
Chris@16:             N,
Chris@16:             T
Chris@16:         >::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct insertion_sort_dims_insert<0> {
Chris@16:     template<class Begin, class T>
Chris@16:     struct apply {
Chris@16:         typedef list<T, dimensionless_type> type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct insertion_sort_dims_mpl_sequence {
Chris@16:     template<class Begin>
Chris@16:     struct apply {
Chris@16:         typedef typename insertion_sort_dims_mpl_sequence<N - 1>::template apply<typename mpl::next<Begin>::type>::type next;
Chris@16:         typedef typename insertion_sort_dims_insert<(next::size::value)>::template apply<next, typename mpl::deref<Begin>::type>::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct insertion_sort_dims_mpl_sequence<0> {
Chris@16:     template<class Begin>
Chris@16:     struct apply {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct insertion_sort_dims_impl {
Chris@16:     template<class Begin>
Chris@16:     struct apply {
Chris@16:         typedef typename insertion_sort_dims_impl<N - 1>::template apply<typename Begin::next>::type next;
Chris@16:         typedef typename insertion_sort_dims_insert<(next::size::value)>::template apply<next, typename Begin::item>::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct insertion_sort_dims_impl<0> {
Chris@16:     template<class Begin>
Chris@16:     struct apply {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<class T>
Chris@16: struct sort_dims
Chris@16: {
Chris@16:     typedef typename insertion_sort_dims_mpl_sequence<mpl::size<T>::value>::template apply<typename mpl::begin<T>::type>::type type;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: template<class T, class Next>
Chris@16: struct sort_dims<list<T, Next> >
Chris@16: {
Chris@16:     typedef typename insertion_sort_dims_impl<list<T, Next>::size::value>::template apply<list<T, Next> >::type type;
Chris@16: };
Chris@16: 
Chris@16: /// sorted sequences can be merged in linear time
Chris@16: template<bool less, bool greater>
Chris@16: struct merge_dimensions_func;
Chris@16: 
Chris@16: template<int N1, int N2>
Chris@16: struct merge_dimensions_impl;
Chris@16: 
Chris@16: template<>
Chris@16: struct merge_dimensions_func<true, false>
Chris@16: {
Chris@16:     template<typename Begin1, typename Begin2, int N1, int N2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef list<
Chris@16:             typename Begin1::item,
Chris@16:             typename merge_dimensions_impl<N1 - 1, N2>::template apply<
Chris@16:                 typename Begin1::next,
Chris@16:                 Begin2
Chris@16:             >::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct merge_dimensions_func<false, true> {
Chris@16:     template<typename Begin1, typename Begin2, int N1, int N2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef list<
Chris@16:             typename Begin2::item,
Chris@16:             typename merge_dimensions_impl<N2 - 1, N1>::template apply<
Chris@16:                 typename Begin2::next,
Chris@16:                 Begin1
Chris@16:             >::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct merge_dimensions_func<false, false> {
Chris@16:     template<typename Begin1, typename Begin2, int N1, int N2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef typename mpl::plus<typename Begin1::item, typename Begin2::item>::type combined;
Chris@16:         typedef typename push_front_if<!is_empty_dim<combined>::value>::template apply<
Chris@16:             typename merge_dimensions_impl<N1 - 1, N2 - 1>::template apply<
Chris@16:                 typename Begin1::next,
Chris@16:                 typename Begin2::next
Chris@16:             >::type,
Chris@16:             combined
Chris@16:         >::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N1, int N2>
Chris@16: struct merge_dimensions_impl {
Chris@16:     template<typename Begin1, typename Begin2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef typename Begin1::item dim1;
Chris@16:         typedef typename Begin2::item dim2;
Chris@16: 
Chris@16:         typedef typename merge_dimensions_func<(mpl::less<dim1,dim2>::value == true),
Chris@16:                 (mpl::less<dim2,dim1>::value == true)>::template apply<
Chris@16:             Begin1,
Chris@16:             Begin2,
Chris@16:             N1,
Chris@16:             N2
Chris@16:         >::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<typename Sequence1, typename Sequence2>
Chris@16: struct merge_dimensions
Chris@16: {
Chris@16:     typedef typename detail::merge_dimensions_impl<Sequence1::size::value, 
Chris@16:                                                    Sequence2::size::value>::template 
Chris@16:         apply<
Chris@16:             Sequence1,
Chris@16:             Sequence2
Chris@16:         >::type type;
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct iterator_to_list
Chris@16: {
Chris@16:     template<typename Begin>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef list<
Chris@16:             typename Begin::item,
Chris@16:             typename iterator_to_list<N - 1>::template apply<
Chris@16:                 typename Begin::next
Chris@16:             >::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct iterator_to_list<0>
Chris@16: {
Chris@16:     template<typename Begin>
Chris@16:     struct apply {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct merge_dimensions_impl<N, 0>
Chris@16: {
Chris@16:     template<typename Begin1, typename Begin2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef typename iterator_to_list<N>::template apply<Begin1>::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct merge_dimensions_impl<0, N>
Chris@16: {
Chris@16:     template<typename Begin1, typename Begin2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef typename iterator_to_list<N>::template apply<Begin2>::type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct merge_dimensions_impl<0, 0>
Chris@16: {
Chris@16:     template<typename Begin1, typename Begin2>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct static_inverse_impl
Chris@16: {
Chris@16:     template<typename Begin>
Chris@16:     struct apply {
Chris@16:         typedef list<
Chris@16:             typename mpl::negate<typename Begin::item>::type,
Chris@16:             typename static_inverse_impl<N - 1>::template apply<
Chris@16:                 typename Begin::next
Chris@16:             >::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct static_inverse_impl<0>
Chris@16: {
Chris@16:     template<typename Begin>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct static_power_impl
Chris@16: {
Chris@16:     template<typename Begin, typename Ex>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef list<
Chris@16:             typename mpl::times<typename Begin::item, Ex>::type,
Chris@16:             typename detail::static_power_impl<N - 1>::template apply<typename Begin::next, Ex>::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct static_power_impl<0>
Chris@16: {
Chris@16:     template<typename Begin, typename Ex>
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<int N>
Chris@16: struct static_root_impl {
Chris@16:     template<class Begin, class Ex>
Chris@16:     struct apply {
Chris@16:         typedef list<
Chris@16:             typename mpl::divides<typename Begin::item, Ex>::type,
Chris@16:             typename detail::static_root_impl<N - 1>::template apply<typename Begin::next, Ex>::type
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct static_root_impl<0> {
Chris@16:     template<class Begin, class Ex>
Chris@16:     struct apply 
Chris@16:     {
Chris@16:         typedef dimensionless_type type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: } // namespace detail
Chris@16: 
Chris@16: } // namespace units
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_UNITS_DIMENSION_IMPL_HPP