1 /*=============================================================================
2     Copyright (c) 2001-2011 Joel de Guzman
3 
4     Distributed under the Boost Software License, Version 1.0. (See accompanying
5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 ==============================================================================*/
7 #if !defined(FUSION_INSERT_07222005_0730)
8 #define FUSION_INSERT_07222005_0730
9 
10 #include <boost/fusion/support/config.hpp>
11 #include <boost/fusion/support/detail/as_fusion_element.hpp>
12 #include <boost/fusion/iterator/mpl/convert_iterator.hpp>
13 #include <boost/fusion/view/joint_view/joint_view.hpp>
14 #include <boost/fusion/view/single_view/single_view.hpp>
15 #include <boost/fusion/view/iterator_range/iterator_range.hpp>
16 #include <boost/fusion/sequence/intrinsic/begin.hpp>
17 #include <boost/fusion/sequence/intrinsic/end.hpp>
18 #include <boost/fusion/adapted/mpl/mpl_iterator.hpp>
19 #include <boost/fusion/support/is_sequence.hpp>
20 #include <boost/utility/enable_if.hpp>
21 
22 namespace boost { namespace fusion
23 {
24     namespace result_of
25     {
26         template <typename Sequence, typename Position, typename T>
27         struct insert
28         {
29             typedef typename detail::as_fusion_element<T>::type element_type;
30             typedef typename convert_iterator<Position>::type pos_type;
31             typedef typename result_of::begin<Sequence>::type first_type;
32             typedef typename result_of::end<Sequence>::type last_type;
33 
34             typedef iterator_range<first_type, pos_type> left_type;
35             typedef iterator_range<pos_type, last_type> right_type;
36             typedef fusion::single_view<element_type> single_view;
37             typedef joint_view<left_type, single_view const> left_insert_type;
38             typedef joint_view<left_insert_type, right_type> type;
39         };
40     }
41 
42     template <typename Sequence, typename Position, typename T>
43     BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
44     inline typename
45         lazy_enable_if<
46             traits::is_sequence<Sequence>
47           , result_of::insert<Sequence const, Position, T>
48         >::type
insert(Sequence const & seq,Position const & pos,T const & x)49     insert(Sequence const& seq, Position const& pos, T const& x)
50     {
51         typedef result_of::insert<
52             Sequence const, Position, T>
53         result_of;
54         typedef typename result_of::left_type left_type;
55         typedef typename result_of::right_type right_type;
56         typedef typename result_of::single_view single_view;
57         typedef typename result_of::left_insert_type left_insert_type;
58         typedef typename result_of::type result;
59 
60         left_type left(fusion::begin(seq), convert_iterator<Position>::call(pos));
61         right_type right(convert_iterator<Position>::call(pos), fusion::end(seq));
62         single_view insert(x);
63         left_insert_type left_insert(left, insert);
64         return result(left_insert, right);
65     }
66 }}
67 
68 #endif
69 
70