libstdc++
bits/string_view.tcc
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1// Components for manipulating non-owning sequences of characters -*- C++ -*-
2
3// Copyright (C) 2013-2022 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/bits/string_view.tcc
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{string_view}
28 */
29
30//
31// N3762 basic_string_view library
32//
33
34#ifndef _GLIBCXX_STRING_VIEW_TCC
35#define _GLIBCXX_STRING_VIEW_TCC 1
36
37#pragma GCC system_header
38
39#if __cplusplus >= 201703L
40
41namespace std _GLIBCXX_VISIBILITY(default)
42{
43_GLIBCXX_BEGIN_NAMESPACE_VERSION
44
45 template<typename _CharT, typename _Traits>
46 constexpr typename basic_string_view<_CharT, _Traits>::size_type
47 basic_string_view<_CharT, _Traits>::
48 find(const _CharT* __str, size_type __pos, size_type __n) const noexcept
49 {
50 __glibcxx_requires_string_len(__str, __n);
51
52 if (__n == 0)
53 return __pos <= _M_len ? __pos : npos;
54 if (__pos >= _M_len)
55 return npos;
56
57 const _CharT __elem0 = __str[0];
58 const _CharT* __first = _M_str + __pos;
59 const _CharT* const __last = _M_str + _M_len;
60 size_type __len = _M_len - __pos;
61
62 while (__len >= __n)
63 {
64 // Find the first occurrence of __elem0:
65 __first = traits_type::find(__first, __len - __n + 1, __elem0);
66 if (!__first)
67 return npos;
68 // Compare the full strings from the first occurrence of __elem0.
69 // We already know that __first[0] == __s[0] but compare them again
70 // anyway because __s is probably aligned, which helps memcmp.
71 if (traits_type::compare(__first, __str, __n) == 0)
72 return __first - _M_str;
73 __len = __last - ++__first;
74 }
75 return npos;
76 }
77
78 template<typename _CharT, typename _Traits>
79 constexpr typename basic_string_view<_CharT, _Traits>::size_type
80 basic_string_view<_CharT, _Traits>::
81 find(_CharT __c, size_type __pos) const noexcept
82 {
83 size_type __ret = npos;
84 if (__pos < this->_M_len)
85 {
86 const size_type __n = this->_M_len - __pos;
87 const _CharT* __p = traits_type::find(this->_M_str + __pos, __n, __c);
88 if (__p)
89 __ret = __p - this->_M_str;
90 }
91 return __ret;
92 }
93
94 template<typename _CharT, typename _Traits>
95 constexpr typename basic_string_view<_CharT, _Traits>::size_type
96 basic_string_view<_CharT, _Traits>::
97 rfind(const _CharT* __str, size_type __pos, size_type __n) const noexcept
98 {
99 __glibcxx_requires_string_len(__str, __n);
100
101 if (__n <= this->_M_len)
102 {
103 __pos = std::min(size_type(this->_M_len - __n), __pos);
104 do
105 {
106 if (traits_type::compare(this->_M_str + __pos, __str, __n) == 0)
107 return __pos;
108 }
109 while (__pos-- > 0);
110 }
111 return npos;
112 }
113
114 template<typename _CharT, typename _Traits>
115 constexpr typename basic_string_view<_CharT, _Traits>::size_type
116 basic_string_view<_CharT, _Traits>::
117 rfind(_CharT __c, size_type __pos) const noexcept
118 {
119 size_type __size = this->_M_len;
120 if (__size > 0)
121 {
122 if (--__size > __pos)
123 __size = __pos;
124 for (++__size; __size-- > 0; )
125 if (traits_type::eq(this->_M_str[__size], __c))
126 return __size;
127 }
128 return npos;
129 }
130
131 template<typename _CharT, typename _Traits>
132 constexpr typename basic_string_view<_CharT, _Traits>::size_type
133 basic_string_view<_CharT, _Traits>::
134 find_first_of(const _CharT* __str, size_type __pos,
135 size_type __n) const noexcept
136 {
137 __glibcxx_requires_string_len(__str, __n);
138 for (; __n && __pos < this->_M_len; ++__pos)
139 {
140 const _CharT* __p = traits_type::find(__str, __n,
141 this->_M_str[__pos]);
142 if (__p)
143 return __pos;
144 }
145 return npos;
146 }
147
148 template<typename _CharT, typename _Traits>
149 constexpr typename basic_string_view<_CharT, _Traits>::size_type
150 basic_string_view<_CharT, _Traits>::
151 find_last_of(const _CharT* __str, size_type __pos,
152 size_type __n) const noexcept
153 {
154 __glibcxx_requires_string_len(__str, __n);
155 size_type __size = this->size();
156 if (__size && __n)
157 {
158 if (--__size > __pos)
159 __size = __pos;
160 do
161 {
162 if (traits_type::find(__str, __n, this->_M_str[__size]))
163 return __size;
164 }
165 while (__size-- != 0);
166 }
167 return npos;
168 }
169
170 template<typename _CharT, typename _Traits>
171 constexpr typename basic_string_view<_CharT, _Traits>::size_type
172 basic_string_view<_CharT, _Traits>::
173 find_first_not_of(const _CharT* __str, size_type __pos,
174 size_type __n) const noexcept
175 {
176 __glibcxx_requires_string_len(__str, __n);
177 for (; __pos < this->_M_len; ++__pos)
178 if (!traits_type::find(__str, __n, this->_M_str[__pos]))
179 return __pos;
180 return npos;
181 }
182
183 template<typename _CharT, typename _Traits>
184 constexpr typename basic_string_view<_CharT, _Traits>::size_type
185 basic_string_view<_CharT, _Traits>::
186 find_first_not_of(_CharT __c, size_type __pos) const noexcept
187 {
188 for (; __pos < this->_M_len; ++__pos)
189 if (!traits_type::eq(this->_M_str[__pos], __c))
190 return __pos;
191 return npos;
192 }
193
194 template<typename _CharT, typename _Traits>
195 constexpr typename basic_string_view<_CharT, _Traits>::size_type
196 basic_string_view<_CharT, _Traits>::
197 find_last_not_of(const _CharT* __str, size_type __pos,
198 size_type __n) const noexcept
199 {
200 __glibcxx_requires_string_len(__str, __n);
201 size_type __size = this->_M_len;
202 if (__size)
203 {
204 if (--__size > __pos)
205 __size = __pos;
206 do
207 {
208 if (!traits_type::find(__str, __n, this->_M_str[__size]))
209 return __size;
210 }
211 while (__size--);
212 }
213 return npos;
214 }
215
216 template<typename _CharT, typename _Traits>
217 constexpr typename basic_string_view<_CharT, _Traits>::size_type
218 basic_string_view<_CharT, _Traits>::
219 find_last_not_of(_CharT __c, size_type __pos) const noexcept
220 {
221 size_type __size = this->_M_len;
222 if (__size)
223 {
224 if (--__size > __pos)
225 __size = __pos;
226 do
227 {
228 if (!traits_type::eq(this->_M_str[__size], __c))
229 return __size;
230 }
231 while (__size--);
232 }
233 return npos;
234 }
235
236_GLIBCXX_END_NAMESPACE_VERSION
237} // namespace std
238
239#endif // __cplusplus <= 201402L
240
241#endif // _GLIBCXX_STRING_VIEW_TCC
constexpr const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:230
ISO C++ entities toplevel namespace is std.
constexpr auto size(const _Container &__cont) noexcept(noexcept(__cont.size())) -> decltype(__cont.size())
Return the size of a container.
Definition: range_access.h:264