1 
2 #ifndef BOOST_MPL_AUX_TRANSFORM_ITER_HPP_INCLUDED
3 #define BOOST_MPL_AUX_TRANSFORM_ITER_HPP_INCLUDED
4 
5 // Copyright Aleksey Gurtovoy 2000-2004
6 //
7 // Distributed under the Boost Software License, Version 1.0.
8 // (See accompanying file LICENSE_1_0.txt or copy at
9 // http://www.boost.org/LICENSE_1_0.txt)
10 //
11 // See http://www.boost.org/libs/mpl for documentation.
12 
13 // $Id$
14 // $Date$
15 // $Revision$
16 
17 #include <boost/mpl/apply.hpp>
18 #include <boost/mpl/iterator_tags.hpp>
19 #include <boost/mpl/next.hpp>
20 #include <boost/mpl/deref.hpp>
21 #include <boost/mpl/aux_/lambda_spec.hpp>
22 #include <boost/mpl/aux_/config/ctps.hpp>
23 #include <boost/type_traits/is_same.hpp>
24 
25 namespace boost { namespace mpl {
26 
27 namespace aux {
28 
29 #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
30 
31 template<
32       typename Iterator
33     , typename LastIterator
34     , typename F
35     >
36 struct transform_iter
37 {
38     typedef Iterator base;
39     typedef forward_iterator_tag category;
40     typedef transform_iter< typename mpl::next<base>::type,LastIterator,F > next;
41 
42     typedef typename apply1<
43           F
44         , typename deref<base>::type
45         >::type type;
46 };
47 
48 template<
49       typename LastIterator
50     , typename F
51     >
52 struct transform_iter< LastIterator,LastIterator,F >
53 {
54     typedef LastIterator base;
55     typedef forward_iterator_tag category;
56 };
57 
58 #else
59 
60 template<
61       typename Iterator
62     , typename LastIterator
63     , typename F
64     >
65 struct transform_iter;
66 
67 template< bool >
68 struct transform_iter_impl
69 {
70     template<
71           typename Iterator
72         , typename LastIterator
73         , typename F
74         >
75     struct result_
76     {
77         typedef Iterator base;
78         typedef forward_iterator_tag category;
79         typedef transform_iter< typename mpl::next<Iterator>::type,LastIterator,F > next;
80 
81         typedef typename apply1<
82               F
83             , typename deref<Iterator>::type
84             >::type type;
85     };
86 };
87 
88 template<>
89 struct transform_iter_impl<true>
90 {
91     template<
92           typename Iterator
93         , typename LastIterator
94         , typename F
95         >
96     struct result_
97     {
98         typedef Iterator base;
99         typedef forward_iterator_tag category;
100     };
101 };
102 
103 template<
104       typename Iterator
105     , typename LastIterator
106     , typename F
107     >
108 struct transform_iter
109     : transform_iter_impl<
110           ::boost::is_same<Iterator,LastIterator>::value
111         >::template result_< Iterator,LastIterator,F >
112 {
113 };
114 
115 #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
116 
117 } // namespace aux
118 
119 BOOST_MPL_AUX_PASS_THROUGH_LAMBDA_SPEC(3, aux::transform_iter)
120 
121 }}
122 
123 #endif // BOOST_MPL_AUX_TRANSFORM_ITER_HPP_INCLUDED
124