1 
2 #ifndef BOOST_MPL_TRANSFORM_HPP_INCLUDED
3 #define BOOST_MPL_TRANSFORM_HPP_INCLUDED
4 
5 // Copyright Aleksey Gurtovoy 2000-2004
6 // Copyright David Abrahams 2003-2004
7 //
8 // Distributed under the Boost Software License, Version 1.0.
9 // (See accompanying file LICENSE_1_0.txt or copy at
10 // http://www.boost.org/LICENSE_1_0.txt)
11 //
12 // See http://www.boost.org/libs/mpl for documentation.
13 
14 // $Id$
15 // $Date$
16 // $Revision$
17 
18 #include <boost/mpl/fold.hpp>
19 #include <boost/mpl/reverse_fold.hpp>
20 #include <boost/mpl/pair_view.hpp>
21 #include <boost/mpl/is_sequence.hpp>
22 #include <boost/mpl/eval_if.hpp>
23 #include <boost/mpl/lambda.hpp>
24 #include <boost/mpl/bind.hpp>
25 #include <boost/mpl/or.hpp>
26 #include <boost/mpl/not.hpp>
27 #include <boost/mpl/aux_/na.hpp>
28 #include <boost/mpl/aux_/inserter_algorithm.hpp>
29 
30 namespace boost { namespace mpl {
31 
32 namespace aux {
33 
34 template<
35       typename Seq
36     , typename Op
37     , typename In
38     >
39 struct transform1_impl
40     : fold<
41           Seq
42         , typename In::state
43         , bind2< typename lambda< typename In::operation >::type
44             , _1
45             , bind1< typename lambda<Op>::type, _2>
46             >
47         >
48 {
49 };
50 
51 template<
52       typename Seq
53     , typename Op
54     , typename In
55     >
56 struct reverse_transform1_impl
57     : reverse_fold<
58           Seq
59         , typename In::state
60         , bind2< typename lambda< typename In::operation >::type
61             , _1
62             , bind1< typename lambda<Op>::type, _2>
63             >
64         >
65 {
66 };
67 
68 template<
69       typename Seq1
70     , typename Seq2
71     , typename Op
72     , typename In
73     >
74 struct transform2_impl
75     : fold<
76           pair_view<Seq1,Seq2>
77         , typename In::state
78         , bind2< typename lambda< typename In::operation >::type
79             , _1
80             , bind2<
81                   typename lambda<Op>::type
82                 , bind1<first<>,_2>
83                 , bind1<second<>,_2>
84                 >
85             >
86         >
87 {
88 };
89 
90 template<
91       typename Seq1
92     , typename Seq2
93     , typename Op
94     , typename In
95     >
96 struct reverse_transform2_impl
97     : reverse_fold<
98           pair_view<Seq1,Seq2>
99         , typename In::state
100         , bind2< typename lambda< typename In::operation >::type
101             , _1
102             , bind2< typename lambda< Op >::type
103                 , bind1<first<>,_2>
104                 , bind1<second<>,_2>
105                 >
106             >
107         >
108 {
109 };
110 
111 } // namespace aux
112 
113 BOOST_MPL_AUX_INSERTER_ALGORITHM_DEF(3, transform1)
114 BOOST_MPL_AUX_INSERTER_ALGORITHM_DEF(4, transform2)
115 
116 #define AUX778076_TRANSFORM_DEF(name)                                   \
117 template<                                                               \
118       typename BOOST_MPL_AUX_NA_PARAM(Seq1)                             \
119     , typename BOOST_MPL_AUX_NA_PARAM(Seq2OrOperation)                  \
120     , typename BOOST_MPL_AUX_NA_PARAM(OperationOrInserter)              \
121     , typename BOOST_MPL_AUX_NA_PARAM(Inserter)                         \
122     >                                                                   \
123 struct name                                                             \
124 {                                                                       \
125     typedef typename eval_if<                                           \
126           or_<                                                          \
127               is_na<OperationOrInserter>                                \
128             , is_lambda_expression< Seq2OrOperation >                   \
129             , not_< is_sequence<Seq2OrOperation> >                      \
130             >                                                           \
131         , name##1<Seq1,Seq2OrOperation,OperationOrInserter>             \
132         , name##2<Seq1,Seq2OrOperation,OperationOrInserter,Inserter>    \
133         >::type type;                                                   \
134 };                                                                      \
135 BOOST_MPL_AUX_NA_SPEC(4, name)                                          \
136 /**/
137 
138 AUX778076_TRANSFORM_DEF(transform)
139 AUX778076_TRANSFORM_DEF(reverse_transform)
140 
141 #undef AUX778076_TRANSFORM_DEF
142 
143 }}
144 
145 #endif // BOOST_MPL_TRANSFORM_HPP_INCLUDED
146