1 | /*============================================================================= |
---|---|
2 | Copyright (c) 2001-2011 Joel de Guzman |
3 | Copyright (c) 2005 Eric Niebler |
4 | |
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(FUSION_NEXT_IMPL_07172005_0836) |
9 | #define FUSION_NEXT_IMPL_07172005_0836 |
10 | |
11 | #include <boost/fusion/support/config.hpp> |
12 | #include <boost/fusion/iterator/next.hpp> |
13 | #include <boost/fusion/iterator/equal_to.hpp> |
14 | #include <boost/mpl/eval_if.hpp> |
15 | #include <boost/mpl/identity.hpp> |
16 | #include <boost/type_traits/is_const.hpp> |
17 | #include <boost/type_traits/add_const.hpp> |
18 | |
19 | namespace boost { namespace fusion |
20 | { |
21 | struct cons_iterator_tag; |
22 | |
23 | template <typename Cons> |
24 | struct cons_iterator; |
25 | |
26 | namespace extension |
27 | { |
28 | template <typename Tag> |
29 | struct next_impl; |
30 | |
31 | template <> |
32 | struct next_impl<cons_iterator_tag> |
33 | { |
34 | template <typename Iterator> |
35 | struct apply |
36 | { |
37 | typedef typename Iterator::cons_type cons_type; |
38 | typedef typename cons_type::cdr_type cdr_type; |
39 | |
40 | typedef cons_iterator< |
41 | typename mpl::eval_if< |
42 | is_const<cons_type> |
43 | , add_const<cdr_type> |
44 | , mpl::identity<cdr_type> |
45 | >::type> |
46 | type; |
47 | |
48 | BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED |
49 | static type |
50 | call(Iterator const& i) |
51 | { |
52 | return type(i.cons.cdr); |
53 | } |
54 | }; |
55 | }; |
56 | } |
57 | }} |
58 | |
59 | #endif |
60 | |
61 | |
62 |