1 /*=============================================================================
2     Boost.Wave: A Standard compliant C++ preprocessor library
3 
4     http://www.boost.org/
5 
6     Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under the Boost
7     Software License, Version 1.0. (See accompanying file
8     LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 =============================================================================*/
10 
11 #if !defined(TRANSFORM_ITERATOR_HPP_D492C659_88C7_4258_8C42_192F9AE80EC0_INCLUDED)
12 #define TRANSFORM_ITERATOR_HPP_D492C659_88C7_4258_8C42_192F9AE80EC0_INCLUDED
13 
14 #include <boost/config.hpp>
15 #include <boost/iterator_adaptors.hpp>
16 #include <boost/iterator/transform_iterator.hpp>
17 
18 #include <boost/assert.hpp>
19 
20 // this must occur after all of the includes and before any code appears
21 #ifdef BOOST_HAS_ABI_HEADERS
22 #include BOOST_ABI_PREFIX
23 #endif
24 
25 ///////////////////////////////////////////////////////////////////////////////
26 namespace boost {
27 namespace wave {
28 namespace impl {
29 
30 ///////////////////////////////////////////////////////////////////////////////
31 //
32 //  The new Boost.Iterator library already conatins a transform_iterator usable
33 //  for our needs. The code below wraps this up.
34 //
35 ///////////////////////////////////////////////////////////////////////////////
36     template <class AdaptableUnaryFunctionT, class IteratorT>
37     class ref_transform_iterator_generator
38     {
39         typedef typename AdaptableUnaryFunctionT::result_type   return_type;
40         typedef typename AdaptableUnaryFunctionT::argument_type argument_type;
41 
42     public:
43         typedef boost::transform_iterator<
44                 return_type (*)(argument_type), IteratorT, return_type>
45             type;
46     };
47 
48     template <class AdaptableUnaryFunctionT, class IteratorT>
49     inline
50     typename ref_transform_iterator_generator<
51         AdaptableUnaryFunctionT, IteratorT>::type
make_ref_transform_iterator(IteratorT base,AdaptableUnaryFunctionT const & f)52     make_ref_transform_iterator(
53         IteratorT base, AdaptableUnaryFunctionT const &f)
54     {
55         typedef typename ref_transform_iterator_generator<
56                 AdaptableUnaryFunctionT, IteratorT>::type
57             iterator_type;
58         return iterator_type(base, f.transform);
59     }
60 
61     //  Retrieve the token value given a parse node
62     //  This is used in conjunction with the ref_transform_iterator above, to
63     //  get the token values while iterating directly over the parse tree.
64     template <typename TokenT, typename ParseTreeNodeT>
65     struct get_token_value {
66 
67         typedef TokenT const &result_type;
68         typedef ParseTreeNodeT const &argument_type;
69 
70         static result_type
transformboost::wave::impl::get_token_value71         transform (argument_type node)
72         {
73             BOOST_ASSERT(1 == std::distance(node.value.begin(),
74                 node.value.end()));
75             return *node.value.begin();
76         }
77     };
78 
79 ///////////////////////////////////////////////////////////////////////////////
80 }   // namespace impl
81 }   // namespace wave
82 }   // namespace boost
83 
84 // the suffix header occurs after all of the code
85 #ifdef BOOST_HAS_ABI_HEADERS
86 #include BOOST_ABI_SUFFIX
87 #endif
88 
89 #endif // !defined(TRANSFORM_ITERATOR_HPP_D492C659_88C7_4258_8C42_192F9AE80EC0_INCLUDED)
90