1/*=============================================================================
2 Copyright (c) 1998-2003 Joel de Guzman
3 http://spirit.sourceforge.net/
4
5 Use, modification and distribution is subject to the Boost Software
6 License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
7 http://www.boost.org/LICENSE_1_0.txt)
8============================================================================*/
9#if !defined(BOOST_SPIRIT_SKIPPER_IPP)
10#define BOOST_SPIRIT_SKIPPER_IPP
11
12///////////////////////////////////////////////////////////////////////////////
13namespace boost { namespace spirit {
14
15BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN
16
17 struct space_parser;
18 template <typename BaseT>
19 struct no_skipper_iteration_policy;
20
21 namespace impl
22 {
23 template <typename ST, typename ScannerT, typename BaseT>
24 inline void
25 skipper_skip(
26 ST const& s,
27 ScannerT const& scan,
28 skipper_iteration_policy<BaseT> const&)
29 {
30 typedef scanner_policies<
31 no_skipper_iteration_policy<
32 BOOST_DEDUCED_TYPENAME ScannerT::iteration_policy_t>,
33 BOOST_DEDUCED_TYPENAME ScannerT::match_policy_t,
34 BOOST_DEDUCED_TYPENAME ScannerT::action_policy_t
35 > policies_t;
36
37 scanner<BOOST_DEDUCED_TYPENAME ScannerT::iterator_t, policies_t>
38 scan2(scan.first, scan.last, policies_t(scan));
39 typedef typename ScannerT::iterator_t iterator_t;
40
41 for (;;)
42 {
43 iterator_t save = scan.first;
44 if (!s.parse(scan2))
45 {
46 scan.first = save;
47 break;
48 }
49 }
50 }
51
52 template <typename ST, typename ScannerT, typename BaseT>
53 inline void
54 skipper_skip(
55 ST const& s,
56 ScannerT const& scan,
57 no_skipper_iteration_policy<BaseT> const&)
58 {
59 for (;;)
60 {
61 typedef typename ScannerT::iterator_t iterator_t;
62 iterator_t save = scan.first;
63 if (!s.parse(scan))
64 {
65 scan.first = save;
66 break;
67 }
68 }
69 }
70
71 template <typename ST, typename ScannerT>
72 inline void
73 skipper_skip(
74 ST const& s,
75 ScannerT const& scan,
76 iteration_policy const&)
77 {
78 for (;;)
79 {
80 typedef typename ScannerT::iterator_t iterator_t;
81 iterator_t save = scan.first;
82 if (!s.parse(scan))
83 {
84 scan.first = save;
85 break;
86 }
87 }
88 }
89
90 template <typename SkipT>
91 struct phrase_parser
92 {
93 template <typename IteratorT, typename ParserT>
94 static parse_info<IteratorT>
95 parse(
96 IteratorT const& first_,
97 IteratorT const& last,
98 ParserT const& p,
99 SkipT const& skip)
100 {
101 typedef skip_parser_iteration_policy<SkipT> it_policy_t;
102 typedef scanner_policies<it_policy_t> scan_policies_t;
103 typedef scanner<IteratorT, scan_policies_t> scanner_t;
104
105 it_policy_t iter_policy(skip);
106 scan_policies_t policies(iter_policy);
107 IteratorT first = first_;
108 scanner_t scan(first, last, policies);
109 match<nil_t> hit = p.parse(scan);
110 return parse_info<IteratorT>(
111 first, hit, hit && (first == last),
112 hit.length());
113 }
114 };
115
116 template <>
117 struct phrase_parser<space_parser>
118 {
119 template <typename IteratorT, typename ParserT>
120 static parse_info<IteratorT>
121 parse(
122 IteratorT const& first_,
123 IteratorT const& last,
124 ParserT const& p,
125 space_parser const&)
126 {
127 typedef skipper_iteration_policy<> it_policy_t;
128 typedef scanner_policies<it_policy_t> scan_policies_t;
129 typedef scanner<IteratorT, scan_policies_t> scanner_t;
130
131 IteratorT first = first_;
132 scanner_t scan(first, last);
133 match<nil_t> hit = p.parse(scan);
134 return parse_info<IteratorT>(
135 first, hit, hit && (first == last),
136 hit.length());
137 }
138 };
139 }
140
141 ///////////////////////////////////////////////////////////////////////////
142 //
143 // Free parse functions using the skippers
144 //
145 ///////////////////////////////////////////////////////////////////////////
146 template <typename IteratorT, typename ParserT, typename SkipT>
147 inline parse_info<IteratorT>
148 parse(
149 IteratorT const& first,
150 IteratorT const& last,
151 parser<ParserT> const& p,
152 parser<SkipT> const& skip)
153 {
154 return impl::phrase_parser<SkipT>::
155 parse(first, last, p.derived(), skip.derived());
156 }
157
158 ///////////////////////////////////////////////////////////////////////////
159 //
160 // Parse function for null terminated strings using the skippers
161 //
162 ///////////////////////////////////////////////////////////////////////////
163 template <typename CharT, typename ParserT, typename SkipT>
164 inline parse_info<CharT const*>
165 parse(
166 CharT const* str,
167 parser<ParserT> const& p,
168 parser<SkipT> const& skip)
169 {
170 CharT const* last = str;
171 while (*last)
172 last++;
173 return parse(str, last, p, skip);
174 }
175
176BOOST_SPIRIT_CLASSIC_NAMESPACE_END
177
178}} // namespace boost::spirit
179
180#endif
181
182

source code of boost/libs/spirit/include/boost/spirit/home/classic/core/scanner/impl/skipper.ipp