libstdc++
iosfwd
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1 // <iosfwd> Forward declarations -*- C++ -*-
2 
3 // Copyright (C) 1997-2022 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/iosfwd
26  * This is a Standard C++ Library header.
27  */
28 
29 //
30 // ISO C++ 14882: 27.2 Forward declarations
31 //
32 
33 #ifndef _GLIBCXX_IOSFWD
34 #define _GLIBCXX_IOSFWD 1
35 
36 #pragma GCC system_header
37 
38 #include <bits/c++config.h>
39 #include <bits/stringfwd.h> // For string forward declarations.
40 #include <bits/postypes.h>
41 
42 namespace std _GLIBCXX_VISIBILITY(default)
43 {
44 _GLIBCXX_BEGIN_NAMESPACE_VERSION
45 
46  /**
47  * @defgroup io I/O
48  *
49  * Nearly all of the I/O classes are parameterized on the type of
50  * characters they read and write. (The major exception is ios_base at
51  * the top of the hierarchy.) This is a change from pre-Standard
52  * streams, which were not templates.
53  *
54  * For ease of use and compatibility, all of the basic_* I/O-related
55  * classes are given typedef names for both of the builtin character
56  * widths (wide and narrow). The typedefs are the same as the
57  * pre-Standard names, for example:
58  *
59  * @code
60  * typedef basic_ifstream<char> ifstream;
61  * @endcode
62  *
63  * Because properly forward-declaring these classes can be difficult, you
64  * should not do it yourself. Instead, include the &lt;iosfwd&gt;
65  * header, which contains only declarations of all the I/O classes as
66  * well as the typedefs. Trying to forward-declare the typedefs
67  * themselves (e.g., <code>class ostream;</code>) is not valid ISO C++.
68  *
69  * For more specific declarations, see
70  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/io.html#std.io.objects
71  *
72  * @{
73  */
74  class ios_base;
75 
76  template<typename _CharT, typename _Traits = char_traits<_CharT> >
77  class basic_ios;
78 
79  template<typename _CharT, typename _Traits = char_traits<_CharT> >
80  class basic_streambuf;
81 
82  template<typename _CharT, typename _Traits = char_traits<_CharT> >
83  class basic_istream;
84 
85  template<typename _CharT, typename _Traits = char_traits<_CharT> >
86  class basic_ostream;
87 
88  template<typename _CharT, typename _Traits = char_traits<_CharT> >
89  class basic_iostream;
90 
91 
92 _GLIBCXX_BEGIN_NAMESPACE_CXX11
93 
94  template<typename _CharT, typename _Traits = char_traits<_CharT>,
95  typename _Alloc = allocator<_CharT> >
96  class basic_stringbuf;
97 
98  template<typename _CharT, typename _Traits = char_traits<_CharT>,
99  typename _Alloc = allocator<_CharT> >
100  class basic_istringstream;
101 
102  template<typename _CharT, typename _Traits = char_traits<_CharT>,
103  typename _Alloc = allocator<_CharT> >
104  class basic_ostringstream;
105 
106  template<typename _CharT, typename _Traits = char_traits<_CharT>,
107  typename _Alloc = allocator<_CharT> >
108  class basic_stringstream;
109 
110 _GLIBCXX_END_NAMESPACE_CXX11
111 
112  template<typename _CharT, typename _Traits = char_traits<_CharT> >
113  class basic_filebuf;
114 
115  template<typename _CharT, typename _Traits = char_traits<_CharT> >
116  class basic_ifstream;
117 
118  template<typename _CharT, typename _Traits = char_traits<_CharT> >
119  class basic_ofstream;
120 
121  template<typename _CharT, typename _Traits = char_traits<_CharT> >
122  class basic_fstream;
123 
124  template<typename _CharT, typename _Traits = char_traits<_CharT> >
125  class istreambuf_iterator;
126 
127  template<typename _CharT, typename _Traits = char_traits<_CharT> >
128  class ostreambuf_iterator;
129 
130 
131  /// Base class for @c char streams.
132  typedef basic_ios<char> ios;
133 
134  /// Base class for @c char buffers.
135  typedef basic_streambuf<char> streambuf;
136 
137  /// Base class for @c char input streams.
138  typedef basic_istream<char> istream;
139 
140  /// Base class for @c char output streams.
141  typedef basic_ostream<char> ostream;
142 
143  /// Base class for @c char mixed input and output streams.
144  typedef basic_iostream<char> iostream;
145 
146  /// Class for @c char memory buffers.
147  typedef basic_stringbuf<char> stringbuf;
148 
149  /// Class for @c char input memory streams.
150  typedef basic_istringstream<char> istringstream;
151 
152  /// Class for @c char output memory streams.
153  typedef basic_ostringstream<char> ostringstream;
154 
155  /// Class for @c char mixed input and output memory streams.
156  typedef basic_stringstream<char> stringstream;
157 
158  /// Class for @c char file buffers.
159  typedef basic_filebuf<char> filebuf;
160 
161  /// Class for @c char input file streams.
162  typedef basic_ifstream<char> ifstream;
163 
164  /// Class for @c char output file streams.
165  typedef basic_ofstream<char> ofstream;
166 
167  /// Class for @c char mixed input and output file streams.
168  typedef basic_fstream<char> fstream;
169 
170 #ifdef _GLIBCXX_USE_WCHAR_T
171  /// Base class for @c wchar_t streams.
172  typedef basic_ios<wchar_t> wios;
173 
174  /// Base class for @c wchar_t buffers.
175  typedef basic_streambuf<wchar_t> wstreambuf;
176 
177  /// Base class for @c wchar_t input streams.
178  typedef basic_istream<wchar_t> wistream;
179 
180  /// Base class for @c wchar_t output streams.
181  typedef basic_ostream<wchar_t> wostream;
182 
183  /// Base class for @c wchar_t mixed input and output streams.
184  typedef basic_iostream<wchar_t> wiostream;
185 
186  /// Class for @c wchar_t memory buffers.
187  typedef basic_stringbuf<wchar_t> wstringbuf;
188 
189  /// Class for @c wchar_t input memory streams.
190  typedef basic_istringstream<wchar_t> wistringstream;
191 
192  /// Class for @c wchar_t output memory streams.
193  typedef basic_ostringstream<wchar_t> wostringstream;
194 
195  /// Class for @c wchar_t mixed input and output memory streams.
196  typedef basic_stringstream<wchar_t> wstringstream;
197 
198  /// Class for @c wchar_t file buffers.
199  typedef basic_filebuf<wchar_t> wfilebuf;
200 
201  /// Class for @c wchar_t input file streams.
202  typedef basic_ifstream<wchar_t> wifstream;
203 
204  /// Class for @c wchar_t output file streams.
205  typedef basic_ofstream<wchar_t> wofstream;
206 
207  /// Class for @c wchar_t mixed input and output file streams.
208  typedef basic_fstream<wchar_t> wfstream;
209 #endif
210 
211 #if __cplusplus >= 202002L && _GLIBCXX_USE_CXX11_ABI
212  template<typename _CharT, typename _Traits = char_traits<_CharT>,
213  typename _Allocator = allocator<_CharT>>
214  class basic_syncbuf;
215  template<typename _CharT, typename _Traits = char_traits<_CharT>,
216  typename _Allocator = allocator<_CharT>>
217  class basic_osyncstream;
218 
219  using syncbuf = basic_syncbuf<char>;
220  using osyncstream = basic_osyncstream<char>;
221 
222 #ifdef _GLIBCXX_USE_WCHAR_T
223  using wsyncbuf = basic_syncbuf<wchar_t>;
224  using wosyncstream = basic_osyncstream<wchar_t>;
225 #endif
226 #endif // C++20 && CXX11_ABI
227 
228 #if __cplusplus > 202002L
229  template<typename _CharT, typename _Traits = char_traits<_CharT>>
230  class basic_spanbuf;
231  template<typename _CharT, typename _Traits = char_traits<_CharT>>
232  class basic_ispanstream;
233  template<typename _CharT, typename _Traits = char_traits<_CharT>>
234  class basic_ospanstream;
235  template<typename _CharT, typename _Traits = char_traits<_CharT>>
236  class basic_spanstream;
237 
238  using spanbuf = basic_spanbuf<char>;
239  using ispanstream = basic_ispanstream<char>;
240  using ospanstream = basic_ospanstream<char>;
241  using spanstream = basic_spanstream<char>;
242 
243 #ifdef _GLIBCXX_USE_WCHAR_T
244  using wspanbuf = basic_spanbuf<wchar_t>;
245  using wispanstream = basic_ispanstream<wchar_t>;
246  using wospanstream = basic_ospanstream<wchar_t>;
247  using wspanstream = basic_spanstream<wchar_t>;
248 #endif
249 #endif // C++23
250 
251  /** @} */
252 
253 _GLIBCXX_END_NAMESPACE_VERSION
254 } // namespace
255 
256 #endif /* _GLIBCXX_IOSFWD */