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_DEREF_05042005_1019)
8#define FUSION_DEREF_05042005_1019
9
10#include <boost/fusion/support/config.hpp>
11#include <boost/fusion/support/iterator_base.hpp>
12#include <boost/fusion/support/tag_of.hpp>
13
14namespace boost { namespace fusion
15{
16 // Special tags:
17 struct iterator_facade_tag; // iterator facade tag
18 struct boost_array_iterator_tag; // boost::array iterator tag
19 struct mpl_iterator_tag; // mpl sequence iterator tag
20 struct std_pair_iterator_tag; // std::pair iterator tag
21
22 namespace extension
23 {
24 template <typename Tag>
25 struct deref_impl
26 {
27 template <typename Iterator>
28 struct apply {};
29 };
30
31 template <>
32 struct deref_impl<iterator_facade_tag>
33 {
34 template <typename Iterator>
35 struct apply : Iterator::template deref<Iterator> {};
36 };
37
38 template <>
39 struct deref_impl<boost_array_iterator_tag>;
40
41 template <>
42 struct deref_impl<mpl_iterator_tag>;
43
44 template <>
45 struct deref_impl<std_pair_iterator_tag>;
46 }
47
48 namespace result_of
49 {
50 template <typename Iterator>
51 struct deref
52 : extension::deref_impl<typename detail::tag_of<Iterator>::type>::
53 template apply<Iterator>
54 {};
55 }
56
57 template <typename Iterator>
58 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
59 inline typename result_of::deref<Iterator>::type
60 deref(Iterator const& i)
61 {
62 typedef result_of::deref<Iterator> deref_meta;
63 return deref_meta::call(i);
64 }
65
66 template <typename Iterator>
67 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
68 inline typename result_of::deref<Iterator>::type
69 operator*(iterator_base<Iterator> const& i)
70 {
71 return fusion::deref(i.cast());
72 }
73}}
74
75#endif
76

source code of include/boost/fusion/iterator/deref.hpp