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
42namespace 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 */