libstdc++
iosfwd
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1 // <iosfwd> Forward declarations -*- C++ -*-
2 
3 // Copyright (C) 1997-2024 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/requires_hosted.h> // iostreams
39 
40 #include <bits/c++config.h>
41 #include <bits/stringfwd.h> // For string forward declarations.
42 #include <bits/postypes.h>
43 
44 namespace std _GLIBCXX_VISIBILITY(default)
45 {
46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
47 
48  /**
49  * @defgroup io I/O
50  *
51  * Nearly all of the I/O classes are parameterized on the type of
52  * characters they read and write. (The major exception is ios_base at
53  * the top of the hierarchy.) This is a change from pre-Standard
54  * streams, which were not templates.
55  *
56  * For ease of use and compatibility, all of the basic_* I/O-related
57  * classes are given typedef names for both of the builtin character
58  * widths (wide and narrow). The typedefs are the same as the
59  * pre-Standard names, for example:
60  *
61  * @code
62  * typedef basic_ifstream<char> ifstream;
63  * @endcode
64  *
65  * Because properly forward-declaring these classes can be difficult, you
66  * should not do it yourself. Instead, include the &lt;iosfwd&gt;
67  * header, which contains only declarations of all the I/O classes as
68  * well as the typedefs. Trying to forward-declare the typedefs
69  * themselves (e.g., <code>class ostream;</code>) is not valid ISO C++.
70  *
71  * For more specific declarations, see
72  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/io.html#std.io.objects
73  *
74  * @{
75  */
76  class ios_base;
77 
78  template<typename _CharT, typename _Traits = char_traits<_CharT> >
79  class basic_ios;
80 
81  template<typename _CharT, typename _Traits = char_traits<_CharT> >
82  class basic_streambuf;
83 
84  template<typename _CharT, typename _Traits = char_traits<_CharT> >
85  class basic_istream;
86 
87  template<typename _CharT, typename _Traits = char_traits<_CharT> >
88  class basic_ostream;
89 
90  template<typename _CharT, typename _Traits = char_traits<_CharT> >
91  class basic_iostream;
92 
93 
94 _GLIBCXX_BEGIN_NAMESPACE_CXX11
95 
96  template<typename _CharT, typename _Traits = char_traits<_CharT>,
97  typename _Alloc = allocator<_CharT> >
98  class basic_stringbuf;
99 
100  template<typename _CharT, typename _Traits = char_traits<_CharT>,
101  typename _Alloc = allocator<_CharT> >
102  class basic_istringstream;
103 
104  template<typename _CharT, typename _Traits = char_traits<_CharT>,
105  typename _Alloc = allocator<_CharT> >
106  class basic_ostringstream;
107 
108  template<typename _CharT, typename _Traits = char_traits<_CharT>,
109  typename _Alloc = allocator<_CharT> >
110  class basic_stringstream;
111 
112 _GLIBCXX_END_NAMESPACE_CXX11
113 
114  template<typename _CharT, typename _Traits = char_traits<_CharT> >
115  class basic_filebuf;
116 
117  template<typename _CharT, typename _Traits = char_traits<_CharT> >
118  class basic_ifstream;
119 
120  template<typename _CharT, typename _Traits = char_traits<_CharT> >
121  class basic_ofstream;
122 
123  template<typename _CharT, typename _Traits = char_traits<_CharT> >
124  class basic_fstream;
125 
126  template<typename _CharT, typename _Traits = char_traits<_CharT> >
127  class istreambuf_iterator;
128 
129  template<typename _CharT, typename _Traits = char_traits<_CharT> >
130  class ostreambuf_iterator;
131 
132 
133  /// Base class for @c char streams.
134  typedef basic_ios<char> ios;
135 
136  /// Base class for @c char buffers.
137  typedef basic_streambuf<char> streambuf;
138 
139  /// Base class for @c char input streams.
140  typedef basic_istream<char> istream;
141 
142  /// Base class for @c char output streams.
143  typedef basic_ostream<char> ostream;
144 
145  /// Base class for @c char mixed input and output streams.
146  typedef basic_iostream<char> iostream;
147 
148  /// Class for @c char memory buffers.
149  typedef basic_stringbuf<char> stringbuf;
150 
151  /// Class for @c char input memory streams.
152  typedef basic_istringstream<char> istringstream;
153 
154  /// Class for @c char output memory streams.
155  typedef basic_ostringstream<char> ostringstream;
156 
157  /// Class for @c char mixed input and output memory streams.
158  typedef basic_stringstream<char> stringstream;
159 
160  /// Class for @c char file buffers.
161  typedef basic_filebuf<char> filebuf;
162 
163  /// Class for @c char input file streams.
164  typedef basic_ifstream<char> ifstream;
165 
166  /// Class for @c char output file streams.
167  typedef basic_ofstream<char> ofstream;
168 
169  /// Class for @c char mixed input and output file streams.
170  typedef basic_fstream<char> fstream;
171 
172 #ifdef _GLIBCXX_USE_WCHAR_T
173  /// Base class for @c wchar_t streams.
174  typedef basic_ios<wchar_t> wios;
175 
176  /// Base class for @c wchar_t buffers.
177  typedef basic_streambuf<wchar_t> wstreambuf;
178 
179  /// Base class for @c wchar_t input streams.
180  typedef basic_istream<wchar_t> wistream;
181 
182  /// Base class for @c wchar_t output streams.
183  typedef basic_ostream<wchar_t> wostream;
184 
185  /// Base class for @c wchar_t mixed input and output streams.
186  typedef basic_iostream<wchar_t> wiostream;
187 
188  /// Class for @c wchar_t memory buffers.
189  typedef basic_stringbuf<wchar_t> wstringbuf;
190 
191  /// Class for @c wchar_t input memory streams.
192  typedef basic_istringstream<wchar_t> wistringstream;
193 
194  /// Class for @c wchar_t output memory streams.
195  typedef basic_ostringstream<wchar_t> wostringstream;
196 
197  /// Class for @c wchar_t mixed input and output memory streams.
198  typedef basic_stringstream<wchar_t> wstringstream;
199 
200  /// Class for @c wchar_t file buffers.
201  typedef basic_filebuf<wchar_t> wfilebuf;
202 
203  /// Class for @c wchar_t input file streams.
204  typedef basic_ifstream<wchar_t> wifstream;
205 
206  /// Class for @c wchar_t output file streams.
207  typedef basic_ofstream<wchar_t> wofstream;
208 
209  /// Class for @c wchar_t mixed input and output file streams.
210  typedef basic_fstream<wchar_t> wfstream;
211 #endif
212 
213 #if __cplusplus >= 202002L && _GLIBCXX_USE_CXX11_ABI
214  template<typename _CharT, typename _Traits = char_traits<_CharT>,
215  typename _Allocator = allocator<_CharT>>
216  class basic_syncbuf;
217  template<typename _CharT, typename _Traits = char_traits<_CharT>,
218  typename _Allocator = allocator<_CharT>>
219  class basic_osyncstream;
220 
221  using syncbuf = basic_syncbuf<char>;
222  using osyncstream = basic_osyncstream<char>;
223 
224 #ifdef _GLIBCXX_USE_WCHAR_T
225  using wsyncbuf = basic_syncbuf<wchar_t>;
226  using wosyncstream = basic_osyncstream<wchar_t>;
227 #endif
228 #endif // C++20 && CXX11_ABI
229 
230 #if __cplusplus > 202002L
231  template<typename _CharT, typename _Traits = char_traits<_CharT>>
232  class basic_spanbuf;
233  template<typename _CharT, typename _Traits = char_traits<_CharT>>
234  class basic_ispanstream;
235  template<typename _CharT, typename _Traits = char_traits<_CharT>>
236  class basic_ospanstream;
237  template<typename _CharT, typename _Traits = char_traits<_CharT>>
238  class basic_spanstream;
239 
240  using spanbuf = basic_spanbuf<char>;
241  using ispanstream = basic_ispanstream<char>;
242  using ospanstream = basic_ospanstream<char>;
243  using spanstream = basic_spanstream<char>;
244 
245 #ifdef _GLIBCXX_USE_WCHAR_T
246  using wspanbuf = basic_spanbuf<wchar_t>;
247  using wispanstream = basic_ispanstream<wchar_t>;
248  using wospanstream = basic_ospanstream<wchar_t>;
249  using wspanstream = basic_spanstream<wchar_t>;
250 #endif
251 #endif // C++23
252 
253  /** @} */
254 
255 _GLIBCXX_END_NAMESPACE_VERSION
256 } // namespace
257 
258 #endif /* _GLIBCXX_IOSFWD */