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The C and C++ Include Header Files

cat -n /usr/include/c++/15/bits/stringfwd.h

     1	// <string> Forward declarations -*- C++ -*-
     2	
     3	// Copyright (C) 2001-2025 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 bits/stringfwd.h
    26	 *  This is an internal header file, included by other library headers.
    27	 *  Do not attempt to use it directly. @headername{string}
    28	 */
    29	
    30	//
    31	// ISO C++ 14882: 21 Strings library
    32	//
    33	
    34	#ifndef _STRINGFWD_H
    35	#define _STRINGFWD_H 1
    36	
    37	#ifdef _GLIBCXX_SYSHDR
    38	#pragma GCC system_header
    39	#endif
    40	
    41	#include <bits/c++config.h>
    42	#include <bits/memoryfwd.h>
    43	
    44	namespace std _GLIBCXX_VISIBILITY(default)
    45	{
    46	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    47	
    48	  /**
    49	   *  @defgroup strings Strings
    50	   *
    51	   *  @{
    52	  */
    53	
    54	  template<class _CharT>
    55	    struct char_traits;
    56	
    57	  template<> struct char_traits<char>;
    58	
    59	  template<> struct char_traits<wchar_t>;
    60	
    61	#ifdef _GLIBCXX_USE_CHAR8_T
    62	  template<> struct char_traits<char8_t>;
    63	#endif
    64	
    65	#if __cplusplus >= 201103L
    66	  template<> struct char_traits<char16_t>;
    67	  template<> struct char_traits<char32_t>;
    68	#endif
    69	
    70	_GLIBCXX_BEGIN_NAMESPACE_CXX11
    71	
    72	  template<typename _CharT, typename _Traits = char_traits<_CharT>,
    73	           typename _Alloc = allocator<_CharT> >
    74	    class basic_string;
    75	
    76	_GLIBCXX_END_NAMESPACE_CXX11
    77	
    78	  /// A string of @c char
    79	  typedef basic_string<char>    string;
    80	
    81	  /// A string of @c wchar_t
    82	  typedef basic_string<wchar_t> wstring;
    83	
    84	#ifdef _GLIBCXX_USE_CHAR8_T
    85	  /// A string of @c char8_t
    86	  typedef basic_string<char8_t> u8string;
    87	#endif
    88	
    89	#if __cplusplus >= 201103L
    90	  /// A string of @c char16_t
    91	  typedef basic_string<char16_t> u16string;
    92	
    93	  /// A string of @c char32_t
    94	  typedef basic_string<char32_t> u32string;
    95	#endif
    96	
    97	  /** @}  */
    98	
    99	_GLIBCXX_END_NAMESPACE_VERSION
   100	} // namespace std
   101	
   102	#endif	// _STRINGFWD_H