1/*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
3 Copyright (c) 2005-2006 Dan Marsden
4 Copyright (c) 2018 Kohei Takahashi
5
6 Distributed under the Boost Software License, Version 1.0. (See accompanying
7 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
8==============================================================================*/
9#if !defined(BOOST_FUSION_AT_IMPL_20061029_1946)
10#define BOOST_FUSION_AT_IMPL_20061029_1946
11
12#include <boost/fusion/support/config.hpp>
13#include <boost/fusion/sequence/intrinsic/at.hpp>
14#include <boost/utility/result_of.hpp>
15
16namespace boost { namespace fusion {
17 struct transform_view_tag;
18 struct transform_view2_tag;
19
20 namespace extension
21 {
22 template<typename Tag>
23 struct at_impl;
24
25 template<>
26 struct at_impl<transform_view_tag>
27 {
28 template<typename Seq, typename N>
29 struct apply
30 {
31 typedef typename Seq::transform_type F;
32 typedef typename result_of::at<typename Seq::sequence_type, N>::type value_type;
33 typedef typename boost::result_of<F(value_type)>::type type;
34
35 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
36 static type call(Seq& seq)
37 {
38 return seq.f(boost::fusion::at<N>(seq.seq));
39 }
40 };
41 };
42
43 template<>
44 struct at_impl<transform_view2_tag>
45 {
46 template<typename Seq, typename N>
47 struct apply
48 {
49 typedef typename Seq::transform_type F;
50 typedef typename result_of::at<typename Seq::sequence1_type, N>::type value1_type;
51 typedef typename result_of::at<typename Seq::sequence2_type, N>::type value2_type;
52 typedef typename boost::result_of<F(value1_type, value2_type)>::type type;
53
54 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
55 static type call(Seq& seq)
56 {
57 return seq.f(boost::fusion::at<N>(seq.seq1), boost::fusion::at<N>(seq.seq2));
58 }
59 };
60 };
61 }
62}}
63
64#endif
65