1/*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
3 Copyright (c) 2001-2011 Hartmut Kaiser
4 Copyright (c) 2010 Bryce Lelbach
5
6 Distributed under the Boost Software License, Version 1.0. (See accompanying
7 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
8================================================_==============================*/
9#if !defined(BOOST_SPIRIT_STRING_TRAITS_OCTOBER_2008_1252PM)
10#define BOOST_SPIRIT_STRING_TRAITS_OCTOBER_2008_1252PM
11
12#if defined(_MSC_VER)
13#pragma once
14#endif
15
16#include <boost/spirit/home/support/container.hpp>
17#include <string>
18#include <boost/mpl/bool.hpp>
19#include <boost/mpl/identity.hpp>
20#include <boost/mpl/if.hpp>
21#include <boost/proto/proto_fwd.hpp> // for BOOST_PROTO_DISABLE_IF_IS_CONST
22#include <boost/type_traits/is_const.hpp>
23#if defined(__GNUC__) && (__GNUC__ < 4)
24#include <boost/type_traits/add_const.hpp>
25#endif
26
27namespace boost { namespace spirit { namespace traits
28{
29 ///////////////////////////////////////////////////////////////////////////
30 // Determine if T is a character type
31 ///////////////////////////////////////////////////////////////////////////
32 template <typename T>
33 struct is_char : mpl::false_ {};
34
35 template <typename T>
36 struct is_char<T const> : is_char<T> {};
37
38 template <>
39 struct is_char<char> : mpl::true_ {};
40
41 template <>
42 struct is_char<wchar_t> : mpl::true_ {};
43
44 ///////////////////////////////////////////////////////////////////////////
45 // Determine if T is a string
46 ///////////////////////////////////////////////////////////////////////////
47 template <typename T>
48 struct is_string : mpl::false_ {};
49
50 template <typename T>
51 struct is_string<T const> : is_string<T> {};
52
53 template <>
54 struct is_string<char const*> : mpl::true_ {};
55
56 template <>
57 struct is_string<wchar_t const*> : mpl::true_ {};
58
59 template <>
60 struct is_string<char*> : mpl::true_ {};
61
62 template <>
63 struct is_string<wchar_t*> : mpl::true_ {};
64
65 template <std::size_t N>
66 struct is_string<char[N]> : mpl::true_ {};
67
68 template <std::size_t N>
69 struct is_string<wchar_t[N]> : mpl::true_ {};
70
71 template <std::size_t N>
72 struct is_string<char const[N]> : mpl::true_ {};
73
74 template <std::size_t N>
75 struct is_string<wchar_t const[N]> : mpl::true_ {};
76
77 template <std::size_t N>
78 struct is_string<char(&)[N]> : mpl::true_ {};
79
80 template <std::size_t N>
81 struct is_string<wchar_t(&)[N]> : mpl::true_ {};
82
83 template <std::size_t N>
84 struct is_string<char const(&)[N]> : mpl::true_ {};
85
86 template <std::size_t N>
87 struct is_string<wchar_t const(&)[N]> : mpl::true_ {};
88
89 template <typename T, typename Traits, typename Allocator>
90 struct is_string<std::basic_string<T, Traits, Allocator> > : mpl::true_ {};
91
92 ///////////////////////////////////////////////////////////////////////////
93 // Get the underlying char type of a string
94 ///////////////////////////////////////////////////////////////////////////
95 template <typename T>
96 struct char_type_of;
97
98 template <typename T>
99 struct char_type_of<T const> : char_type_of<T> {};
100
101 template <>
102 struct char_type_of<char> : mpl::identity<char> {};
103
104 template <>
105 struct char_type_of<wchar_t> : mpl::identity<wchar_t> {};
106
107 template <>
108 struct char_type_of<char const*> : mpl::identity<char const> {};
109
110 template <>
111 struct char_type_of<wchar_t const*> : mpl::identity<wchar_t const> {};
112
113 template <>
114 struct char_type_of<char*> : mpl::identity<char> {};
115
116 template <>
117 struct char_type_of<wchar_t*> : mpl::identity<wchar_t> {};
118
119 template <std::size_t N>
120 struct char_type_of<char[N]> : mpl::identity<char> {};
121
122 template <std::size_t N>
123 struct char_type_of<wchar_t[N]> : mpl::identity<wchar_t> {};
124
125 template <std::size_t N>
126 struct char_type_of<char const[N]> : mpl::identity<char const> {};
127
128 template <std::size_t N>
129 struct char_type_of<wchar_t const[N]> : mpl::identity<wchar_t const> {};
130
131 template <std::size_t N>
132 struct char_type_of<char(&)[N]> : mpl::identity<char> {};
133
134 template <std::size_t N>
135 struct char_type_of<wchar_t(&)[N]> : mpl::identity<wchar_t> {};
136
137 template <std::size_t N>
138 struct char_type_of<char const(&)[N]> : mpl::identity<char const> {};
139
140 template <std::size_t N>
141 struct char_type_of<wchar_t const(&)[N]> : mpl::identity<wchar_t const> {};
142
143 template <typename T, typename Traits, typename Allocator>
144 struct char_type_of<std::basic_string<T, Traits, Allocator> >
145 : mpl::identity<T> {};
146
147 ///////////////////////////////////////////////////////////////////////////
148 // Get the C string from a string
149 ///////////////////////////////////////////////////////////////////////////
150 template <typename String>
151 struct extract_c_string;
152
153 template <typename String>
154 struct extract_c_string
155 {
156 typedef typename char_type_of<String>::type char_type;
157
158 template <typename T>
159 static T const* call (T* str)
160 {
161 return (T const*)str;
162 }
163
164 template <typename T>
165 static T const* call (T const* str)
166 {
167 return str;
168 }
169 };
170
171 // Forwarder that strips const
172 template <typename T>
173 struct extract_c_string<T const>
174 {
175 typedef typename extract_c_string<T>::char_type char_type;
176
177 static typename extract_c_string<T>::char_type const* call (T const str)
178 {
179 return extract_c_string<T>::call(str);
180 }
181 };
182
183 // Forwarder that strips references
184 template <typename T>
185 struct extract_c_string<T&>
186 {
187 typedef typename extract_c_string<T>::char_type char_type;
188
189 static typename extract_c_string<T>::char_type const* call (T& str)
190 {
191 return extract_c_string<T>::call(str);
192 }
193 };
194
195 // Forwarder that strips const references
196 template <typename T>
197 struct extract_c_string<T const&>
198 {
199 typedef typename extract_c_string<T>::char_type char_type;
200
201 static typename extract_c_string<T>::char_type const* call (T const& str)
202 {
203 return extract_c_string<T>::call(str);
204 }
205 };
206
207 template <typename T, typename Traits, typename Allocator>
208 struct extract_c_string<std::basic_string<T, Traits, Allocator> >
209 {
210 typedef T char_type;
211
212 typedef std::basic_string<T, Traits, Allocator> string;
213
214 static T const* call (string const& str)
215 {
216 return str.c_str();
217 }
218 };
219
220 template <typename T>
221 typename extract_c_string<T*>::char_type const*
222 get_c_string (T* str)
223 {
224 return extract_c_string<T*>::call(str);
225 }
226
227 template <typename T>
228 typename extract_c_string<T const*>::char_type const*
229 get_c_string (T const* str)
230 {
231 return extract_c_string<T const*>::call(str);
232 }
233
234 template <typename String>
235 typename extract_c_string<String>::char_type const*
236 get_c_string (String& str)
237 {
238 return extract_c_string<String>::call(str);
239 }
240
241 template <typename String>
242 typename extract_c_string<String>::char_type const*
243 get_c_string (String const& str)
244 {
245 return extract_c_string<String>::call(str);
246 }
247
248 ///////////////////////////////////////////////////////////////////////////
249 // Get the begin/end iterators from a string
250 ///////////////////////////////////////////////////////////////////////////
251
252 // Implementation for C-style strings.
253
254// gcc 3.x.x has problems resolving ambiguities here
255#if defined(__GNUC__) && (__GNUC__ < 4)
256 template <typename T>
257 inline typename add_const<T>::type * get_begin(T* str) { return str; }
258
259 template <typename T>
260 inline typename add_const<T>::type* get_end(T* str)
261 {
262 T* last = str;
263 while (*last)
264 last++;
265 return last;
266 }
267#else
268 template <typename T>
269 inline T const* get_begin(T const* str) { return str; }
270
271 template <typename T>
272 inline T* get_begin(T* str) { return str; }
273
274 template <typename T>
275 inline T const* get_end(T const* str)
276 {
277 T const* last = str;
278 while (*last)
279 last++;
280 return last;
281 }
282
283 template <typename T>
284 inline T* get_end(T* str)
285 {
286 T* last = str;
287 while (*last)
288 last++;
289 return last;
290 }
291#endif
292
293 // Implementation for containers (includes basic_string).
294 template <typename T, typename Str>
295 inline typename Str::const_iterator get_begin(Str const& str)
296 { return str.begin(); }
297
298 template <typename T, typename Str>
299 inline typename Str::iterator
300 get_begin(Str& str BOOST_PROTO_DISABLE_IF_IS_CONST(Str))
301 { return str.begin(); }
302
303 template <typename T, typename Str>
304 inline typename Str::const_iterator get_end(Str const& str)
305 { return str.end(); }
306
307 template <typename T, typename Str>
308 inline typename Str::iterator
309 get_end(Str& str BOOST_PROTO_DISABLE_IF_IS_CONST(Str))
310 { return str.end(); }
311
312 // Default implementation for other types: try a C-style string
313 // conversion.
314 // These overloads are explicitly disabled for containers,
315 // as they would be ambiguous with the previous ones.
316 template <typename T, typename Str>
317 inline typename disable_if<is_container<Str>
318 , T const*>::type get_begin(Str const& str)
319 { return str; }
320
321 template <typename T, typename Str>
322 inline typename disable_if<is_container<Str>
323 , T const*>::type get_end(Str const& str)
324 { return get_end(get_begin<T>(str)); }
325}
326
327namespace result_of
328{
329 template <typename Char, typename T, typename Enable = void>
330 struct get_begin
331 {
332 typedef typename traits::char_type_of<T>::type char_type;
333
334 typedef typename mpl::if_<
335 is_const<char_type>
336 , char_type const
337 , char_type
338 >::type* type;
339 };
340
341 template <typename Char, typename Str>
342 struct get_begin<Char, Str
343 , typename enable_if<traits::is_container<Str> >::type>
344 {
345 typedef typename mpl::if_<
346 is_const<Str>
347 , typename Str::const_iterator
348 , typename Str::iterator
349 >::type type;
350 };
351
352 template <typename Char, typename T>
353 struct get_end : get_begin<Char, T> {};
354}
355
356}}
357
358#endif
359