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_CONS_07172005_0843)
9 #define FUSION_CONS_07172005_0843
10 
11 #include <boost/fusion/support/config.hpp>
12 #include <boost/fusion/support/void.hpp>
13 #include <boost/fusion/support/detail/enabler.hpp>
14 #include <boost/fusion/container/list/cons_fwd.hpp>
15 #include <boost/fusion/support/detail/access.hpp>
16 #include <boost/fusion/sequence/intrinsic/begin.hpp>
17 #include <boost/fusion/sequence/intrinsic/end.hpp>
18 #include <boost/fusion/iterator/next.hpp>
19 #include <boost/fusion/iterator/deref.hpp>
20 #include <boost/fusion/container/list/nil.hpp>
21 #include <boost/fusion/container/list/cons_iterator.hpp>
22 #include <boost/fusion/container/list/detail/begin_impl.hpp>
23 #include <boost/fusion/container/list/detail/end_impl.hpp>
24 #include <boost/fusion/container/list/detail/at_impl.hpp>
25 #include <boost/fusion/container/list/detail/value_at_impl.hpp>
26 #include <boost/fusion/container/list/detail/empty_impl.hpp>
27 #include <boost/type_traits/is_convertible.hpp>
28 #include <boost/type_traits/is_base_of.hpp>
29 #include <boost/utility/enable_if.hpp>
30 #include <boost/fusion/support/sequence_base.hpp>
31 #include <boost/fusion/support/is_sequence.hpp>
32 #include <boost/mpl/int.hpp>
33 #include <boost/mpl/bool.hpp>
34 #include <boost/mpl/and.hpp>
35 #include <boost/mpl/not.hpp>
36 
37 namespace boost { namespace fusion
38 {
39     struct cons_tag;
40     struct forward_traversal_tag;
41     struct fusion_sequence_tag;
42 
43     template <typename Car, typename Cdr /*= nil_*/>
44     struct cons : sequence_base<cons<Car, Cdr> >
45     {
46         typedef mpl::int_<Cdr::size::value+1> size;
47         typedef cons_tag fusion_tag;
48         typedef fusion_sequence_tag tag; // this gets picked up by MPL
49         typedef mpl::false_ is_view;
50         typedef forward_traversal_tag category;
51         typedef Car car_type;
52         typedef Cdr cdr_type;
53 
54         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons55         cons()
56             : car(), cdr() {}
57 
58         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons59         explicit cons(typename detail::call_param<Car>::type in_car)
60             : car(in_car), cdr() {}
61 
62         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons63         cons(
64             typename detail::call_param<Car>::type in_car
65           , typename detail::call_param<Cdr>::type in_cdr)
66             : car(in_car), cdr(in_cdr) {}
67 
68         template <typename Car2, typename Cdr2>
69         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons70         cons(cons<Car2, Cdr2> const& rhs)
71             : car(rhs.car), cdr(rhs.cdr) {}
72 
73         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons74         cons(cons const& rhs)
75             : car(rhs.car), cdr(rhs.cdr) {}
76 
77         template <typename Sequence>
78         BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons79         cons(
80             Sequence const& seq
81           , typename boost::enable_if<
82                 mpl::and_<
83                     traits::is_sequence<Sequence>
84                   , mpl::not_<is_base_of<cons, Sequence> >
85                   , mpl::not_<is_convertible<Sequence, Car> > > // use copy to car instead
86               , detail::enabler_
87             >::type = detail::enabler
88         )
89             : car(*fusion::begin(seq))
90             , cdr(fusion::next(fusion::begin(seq)), mpl::true_()) {}
91 
92         template <typename Iterator>
93         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
consboost::fusion::cons94         cons(Iterator const& iter, mpl::true_ /*this_is_an_iterator*/)
95             : car(*iter)
96             , cdr(fusion::next(iter), mpl::true_()) {}
97 
98         template <typename Car2, typename Cdr2>
99         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
operator =boost::fusion::cons100         cons& operator=(cons<Car2, Cdr2> const& rhs)
101         {
102             car = rhs.car;
103             cdr = rhs.cdr;
104             return *this;
105         }
106 
107         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
operator =boost::fusion::cons108         cons& operator=(cons const& rhs)
109         {
110             car = rhs.car;
111             cdr = rhs.cdr;
112             return *this;
113         }
114 
115         template <typename Sequence>
116         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
117         typename boost::enable_if<
118             mpl::and_<
119                 traits::is_sequence<Sequence>
120               , mpl::not_<is_convertible<Sequence, Car> > >
121           , cons&>::type
operator =boost::fusion::cons122         operator=(Sequence const& seq)
123         {
124             typedef typename result_of::begin<Sequence const>::type Iterator;
125             Iterator iter = fusion::begin(seq);
126             this->assign_from_iter(iter);
127             return *this;
128         }
129 
130         template <typename Iterator>
131         BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
assign_from_iterboost::fusion::cons132         void assign_from_iter(Iterator const& iter)
133         {
134             car = *iter;
135             cdr.assign_from_iter(fusion::next(iter));
136         }
137 
138         car_type car;
139         cdr_type cdr;
140     };
141 }}
142 
143 #endif
144 
145