1 /*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
3 Copyright (c) 2005-2006 Dan Marsden
5 Distributed under the Boost Software License, Version 1.0. (See accompanying
6 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7 ==============================================================================*/
8 #if !defined(BOOST_FUSION_VALUE_AT_IMPL_20061101_0745)
9 #define BOOST_FUSION_VALUE_AT_IMPL_20061101_0745
11 #include <boost/fusion/support/config.hpp>
12 #include <boost/mpl/apply.hpp>
13 #include <boost/fusion/view/transform_view/detail/apply_transform_result.hpp>
14 #include <boost/fusion/sequence/intrinsic/value_at.hpp>
16 namespace boost { namespace fusion {
17 struct transform_view_tag;
18 struct transform_view2_tag;
22 template<typename Tag>
26 struct value_at_impl<transform_view_tag>
28 template<typename Seq, typename N>
31 typedef typename Seq::transform_type F;
32 typedef detail::apply_transform_result<F> transform_type;
33 typedef typename boost::fusion::result_of::value_at<typename Seq::sequence_type, N>::type value_type;
34 typedef typename mpl::apply<transform_type, value_type>::type type;
39 struct value_at_impl<transform_view2_tag>
41 template<typename Seq, typename N>
44 typedef typename Seq::transform_type F;
45 typedef detail::apply_transform_result<F> transform_type;
46 typedef typename boost::fusion::result_of::value_at<typename Seq::sequence1_type, N>::type value1_type;
47 typedef typename boost::fusion::result_of::value_at<typename Seq::sequence2_type, N>::type value2_type;
48 typedef typename mpl::apply<transform_type, value1_type, value2_type>::type type;