libstdc++
string
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1 // Components for manipulating sequences of characters -*- 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/string
26  * This is a Standard C++ Library header.
27  */
28 
29 //
30 // ISO C++ 14882: 21 Strings library
31 //
32 
33 #ifndef _GLIBCXX_STRING
34 #define _GLIBCXX_STRING 1
35 
36 #pragma GCC system_header
37 
38 #include <bits/c++config.h>
39 #include <bits/stringfwd.h>
40 #include <bits/char_traits.h> // NB: In turn includes stl_algobase.h
41 #include <bits/allocator.h>
42 #include <bits/cpp_type_traits.h>
43 #include <bits/localefwd.h> // For operators >>, <<, and getline.
44 #include <bits/ostream_insert.h>
45 #include <bits/stl_iterator_base_types.h>
46 #include <bits/stl_iterator_base_funcs.h>
47 #include <bits/stl_iterator.h>
48 #include <bits/stl_function.h> // For less
49 #include <ext/numeric_traits.h>
50 #include <bits/stl_algobase.h>
51 #include <bits/refwrap.h>
52 #include <bits/range_access.h>
53 #include <bits/basic_string.h>
54 #include <bits/basic_string.tcc>
55 
56 #if __cplusplus >= 201703L && _GLIBCXX_USE_CXX11_ABI
57 namespace std _GLIBCXX_VISIBILITY(default)
58 {
59 _GLIBCXX_BEGIN_NAMESPACE_VERSION
60  namespace pmr {
61  template<typename _Tp> class polymorphic_allocator;
62  template<typename _CharT, typename _Traits = char_traits<_CharT>>
63  using basic_string = std::basic_string<_CharT, _Traits,
64  polymorphic_allocator<_CharT>>;
65  using string = basic_string<char>;
66 #ifdef _GLIBCXX_USE_CHAR8_T
67  using u8string = basic_string<char8_t>;
68 #endif
69  using u16string = basic_string<char16_t>;
70  using u32string = basic_string<char32_t>;
71  using wstring = basic_string<wchar_t>;
72  } // namespace pmr
73 
74  template<typename _Str>
75  struct __hash_string_base
76  : public __hash_base<size_t, _Str>
77  {
78  size_t
79  operator()(const _Str& __s) const noexcept
80  { return hash<basic_string_view<typename _Str::value_type>>{}(__s); }
81  };
82 
83  template<>
84  struct hash<pmr::string>
85  : public __hash_string_base<pmr::string>
86  { };
87 #ifdef _GLIBCXX_USE_CHAR8_T
88  template<>
89  struct hash<pmr::u8string>
90  : public __hash_string_base<pmr::u8string>
91  { };
92 #endif
93  template<>
94  struct hash<pmr::u16string>
95  : public __hash_string_base<pmr::u16string>
96  { };
97  template<>
98  struct hash<pmr::u32string>
99  : public __hash_string_base<pmr::u32string>
100  { };
101  template<>
102  struct hash<pmr::wstring>
103  : public __hash_string_base<pmr::wstring>
104  { };
105 
106 _GLIBCXX_END_NAMESPACE_VERSION
107 } // namespace std
108 #endif // C++17
109 
110 #if __cplusplus > 201703L
111 namespace std _GLIBCXX_VISIBILITY(default)
112 {
113 _GLIBCXX_BEGIN_NAMESPACE_VERSION
114 
115 #define __cpp_lib_erase_if 202002L
116 
117  template<typename _CharT, typename _Traits, typename _Alloc,
118  typename _Predicate>
119  _GLIBCXX20_CONSTEXPR
120  inline typename basic_string<_CharT, _Traits, _Alloc>::size_type
121  erase_if(basic_string<_CharT, _Traits, _Alloc>& __cont, _Predicate __pred)
122  {
123  using namespace __gnu_cxx;
124  const auto __osz = __cont.size();
125  const auto __end = __cont.end();
126  auto __removed = std::__remove_if(__cont.begin(), __end,
127  __ops::__pred_iter(std::ref(__pred)));
128  __cont.erase(__removed, __end);
129  return __osz - __cont.size();
130  }
131 
132  template<typename _CharT, typename _Traits, typename _Alloc, typename _Up>
133  _GLIBCXX20_CONSTEXPR
134  inline typename basic_string<_CharT, _Traits, _Alloc>::size_type
135  erase(basic_string<_CharT, _Traits, _Alloc>& __cont, const _Up& __value)
136  {
137  using namespace __gnu_cxx;
138  const auto __osz = __cont.size();
139  const auto __end = __cont.end();
140  auto __removed = std::__remove_if(__cont.begin(), __end,
141  __ops::__iter_equals_val(__value));
142  __cont.erase(__removed, __end);
143  return __osz - __cont.size();
144  }
145 _GLIBCXX_END_NAMESPACE_VERSION
146 } // namespace std
147 #endif // C++20
148 
149 #endif /* _GLIBCXX_STRING */