xref: /netbsd-src/external/apache2/llvm/dist/libcxx/include/string_view (revision 4d6fc14bc9b0c5bf3e30be318c143ee82cadd108)
1// -*- C++ -*-
2//===------------------------ string_view ---------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_STRING_VIEW
11#define _LIBCPP_STRING_VIEW
12
13/*
14string_view synopsis
15
16namespace std {
17
18    // 7.2, Class template basic_string_view
19    template<class charT, class traits = char_traits<charT>>
20        class basic_string_view;
21
22    template<class charT, class traits>
23    inline constexpr bool ranges::enable_borrowed_range<basic_string_view<charT, traits>> = true;  // C++20
24
25    // 7.9, basic_string_view non-member comparison functions
26    template<class charT, class traits>
27    constexpr bool operator==(basic_string_view<charT, traits> x,
28                              basic_string_view<charT, traits> y) noexcept;
29    template<class charT, class traits>
30    constexpr bool operator!=(basic_string_view<charT, traits> x,
31                              basic_string_view<charT, traits> y) noexcept;
32    template<class charT, class traits>
33    constexpr bool operator< (basic_string_view<charT, traits> x,
34                                 basic_string_view<charT, traits> y) noexcept;
35    template<class charT, class traits>
36    constexpr bool operator> (basic_string_view<charT, traits> x,
37                              basic_string_view<charT, traits> y) noexcept;
38    template<class charT, class traits>
39    constexpr bool operator<=(basic_string_view<charT, traits> x,
40                                 basic_string_view<charT, traits> y) noexcept;
41    template<class charT, class traits>
42    constexpr bool operator>=(basic_string_view<charT, traits> x,
43                              basic_string_view<charT, traits> y) noexcept;
44    // see below, sufficient additional overloads of comparison functions
45
46    // 7.10, Inserters and extractors
47    template<class charT, class traits>
48      basic_ostream<charT, traits>&
49        operator<<(basic_ostream<charT, traits>& os,
50                   basic_string_view<charT, traits> str);
51
52    // basic_string_view typedef names
53    typedef basic_string_view<char> string_view;
54    typedef basic_string_view<char8_t> u8string_view; // C++20
55    typedef basic_string_view<char16_t> u16string_view;
56    typedef basic_string_view<char32_t> u32string_view;
57    typedef basic_string_view<wchar_t> wstring_view;
58
59    template<class charT, class traits = char_traits<charT>>
60    class basic_string_view {
61      public:
62      // types
63      typedef traits traits_type;
64      typedef charT value_type;
65      typedef charT* pointer;
66      typedef const charT* const_pointer;
67      typedef charT& reference;
68      typedef const charT& const_reference;
69      typedef implementation-defined const_iterator;
70      typedef const_iterator iterator;
71      typedef reverse_iterator<const_iterator> const_reverse_iterator;
72      typedef const_reverse_iterator reverse_iterator;
73      typedef size_t size_type;
74      typedef ptrdiff_t difference_type;
75      static constexpr size_type npos = size_type(-1);
76
77      // 7.3, basic_string_view constructors and assignment operators
78      constexpr basic_string_view() noexcept;
79      constexpr basic_string_view(const basic_string_view&) noexcept = default;
80      basic_string_view& operator=(const basic_string_view&) noexcept = default;
81      template<class Allocator>
82      constexpr basic_string_view(const charT* str);
83      constexpr basic_string_view(const charT* str, size_type len);
84
85      // 7.4, basic_string_view iterator support
86      constexpr const_iterator begin() const noexcept;
87      constexpr const_iterator end() const noexcept;
88      constexpr const_iterator cbegin() const noexcept;
89      constexpr const_iterator cend() const noexcept;
90      const_reverse_iterator rbegin() const noexcept;
91      const_reverse_iterator rend() const noexcept;
92      const_reverse_iterator crbegin() const noexcept;
93      const_reverse_iterator crend() const noexcept;
94
95      // 7.5, basic_string_view capacity
96      constexpr size_type size() const noexcept;
97      constexpr size_type length() const noexcept;
98      constexpr size_type max_size() const noexcept;
99      constexpr bool empty() const noexcept;
100
101      // 7.6, basic_string_view element access
102      constexpr const_reference operator[](size_type pos) const;
103      constexpr const_reference at(size_type pos) const;
104      constexpr const_reference front() const;
105      constexpr const_reference back() const;
106      constexpr const_pointer data() const noexcept;
107
108      // 7.7, basic_string_view modifiers
109      constexpr void remove_prefix(size_type n);
110      constexpr void remove_suffix(size_type n);
111      constexpr void swap(basic_string_view& s) noexcept;
112
113      size_type copy(charT* s, size_type n, size_type pos = 0) const;  // constexpr in C++20
114
115      constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const;
116      constexpr int compare(basic_string_view s) const noexcept;
117      constexpr int compare(size_type pos1, size_type n1, basic_string_view s) const;
118      constexpr int compare(size_type pos1, size_type n1,
119                            basic_string_view s, size_type pos2, size_type n2) const;
120      constexpr int compare(const charT* s) const;
121      constexpr int compare(size_type pos1, size_type n1, const charT* s) const;
122      constexpr int compare(size_type pos1, size_type n1,
123                            const charT* s, size_type n2) const;
124      constexpr size_type find(basic_string_view s, size_type pos = 0) const noexcept;
125      constexpr size_type find(charT c, size_type pos = 0) const noexcept;
126      constexpr size_type find(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
127      constexpr size_type find(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
128      constexpr size_type rfind(basic_string_view s, size_type pos = npos) const noexcept;
129      constexpr size_type rfind(charT c, size_type pos = npos) const noexcept;
130      constexpr size_type rfind(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
131      constexpr size_type rfind(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
132      constexpr size_type find_first_of(basic_string_view s, size_type pos = 0) const noexcept;
133      constexpr size_type find_first_of(charT c, size_type pos = 0) const noexcept;
134      constexpr size_type find_first_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
135      constexpr size_type find_first_of(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
136      constexpr size_type find_last_of(basic_string_view s, size_type pos = npos) const noexcept;
137      constexpr size_type find_last_of(charT c, size_type pos = npos) const noexcept;
138      constexpr size_type find_last_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
139      constexpr size_type find_last_of(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
140      constexpr size_type find_first_not_of(basic_string_view s, size_type pos = 0) const noexcept;
141      constexpr size_type find_first_not_of(charT c, size_type pos = 0) const noexcept;
142      constexpr size_type find_first_not_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
143      constexpr size_type find_first_not_of(const charT* s, size_type pos = 0) const noexcept; // noexcept as an extension
144      constexpr size_type find_last_not_of(basic_string_view s, size_type pos = npos) const noexcept;
145      constexpr size_type find_last_not_of(charT c, size_type pos = npos) const noexcept;
146      constexpr size_type find_last_not_of(const charT* s, size_type pos, size_type n) const noexcept; // noexcept as an extension
147      constexpr size_type find_last_not_of(const charT* s, size_type pos = npos) const noexcept; // noexcept as an extension
148
149      constexpr bool starts_with(basic_string_view s) const noexcept; // C++20
150      constexpr bool starts_with(charT c) const noexcept;             // C++20
151      constexpr bool starts_with(const charT* s) const;               // C++20
152      constexpr bool ends_with(basic_string_view s) const noexcept;   // C++20
153      constexpr bool ends_with(charT c) const noexcept;               // C++20
154      constexpr bool ends_with(const charT* s) const;                 // C++20
155
156      constexpr bool contains(basic_string_view s) const noexcept; // C++2b
157      constexpr bool contains(charT c) const noexcept;             // C++2b
158      constexpr bool contains(const charT* s) const;               // C++2b
159
160     private:
161      const_pointer data_;  // exposition only
162      size_type     size_;  // exposition only
163    };
164
165  // 7.11, Hash support
166  template <class T> struct hash;
167  template <> struct hash<string_view>;
168  template <> struct hash<u8string_view>; // C++20
169  template <> struct hash<u16string_view>;
170  template <> struct hash<u32string_view>;
171  template <> struct hash<wstring_view>;
172
173  constexpr basic_string_view<char>     operator "" sv( const char *str,     size_t len ) noexcept;
174  constexpr basic_string_view<wchar_t>  operator "" sv( const wchar_t *str,  size_t len ) noexcept;
175  constexpr basic_string_view<char8_t>  operator "" sv( const char8_t *str,  size_t len ) noexcept; // C++20
176  constexpr basic_string_view<char16_t> operator "" sv( const char16_t *str, size_t len ) noexcept;
177  constexpr basic_string_view<char32_t> operator "" sv( const char32_t *str, size_t len ) noexcept;
178
179}  // namespace std
180
181
182*/
183
184#include <__config>
185#include <__ranges/enable_borrowed_range.h>
186#include <__string>
187#include <iosfwd>
188#include <algorithm>
189#include <compare>
190#include <iterator>
191#include <limits>
192#include <stdexcept>
193#include <version>
194#include <__debug>
195
196#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
197#pragma GCC system_header
198#endif
199
200_LIBCPP_PUSH_MACROS
201#include <__undef_macros>
202
203
204_LIBCPP_BEGIN_NAMESPACE_STD
205
206template<class _CharT, class _Traits = char_traits<_CharT> >
207    class _LIBCPP_TEMPLATE_VIS basic_string_view;
208
209typedef basic_string_view<char>     string_view;
210#ifndef _LIBCPP_HAS_NO_CHAR8_T
211typedef basic_string_view<char8_t>  u8string_view;
212#endif
213typedef basic_string_view<char16_t> u16string_view;
214typedef basic_string_view<char32_t> u32string_view;
215typedef basic_string_view<wchar_t>  wstring_view;
216
217template<class _CharT, class _Traits>
218class
219    _LIBCPP_PREFERRED_NAME(string_view)
220#ifndef _LIBCPP_HAS_NO_CHAR8_T
221    _LIBCPP_PREFERRED_NAME(u8string_view)
222#endif
223    _LIBCPP_PREFERRED_NAME(u16string_view)
224    _LIBCPP_PREFERRED_NAME(u32string_view)
225    _LIBCPP_PREFERRED_NAME(wstring_view)
226    basic_string_view {
227public:
228    // types
229    typedef _Traits                                    traits_type;
230    typedef _CharT                                     value_type;
231    typedef _CharT*                                    pointer;
232    typedef const _CharT*                              const_pointer;
233    typedef _CharT&                                    reference;
234    typedef const _CharT&                              const_reference;
235    typedef const_pointer                              const_iterator; // See [string.view.iterators]
236    typedef const_iterator                             iterator;
237    typedef _VSTD::reverse_iterator<const_iterator>    const_reverse_iterator;
238    typedef const_reverse_iterator                     reverse_iterator;
239    typedef size_t                                     size_type;
240    typedef ptrdiff_t                                  difference_type;
241    static _LIBCPP_CONSTEXPR const size_type npos = -1; // size_type(-1);
242
243    static_assert((!is_array<value_type>::value), "Character type of basic_string_view must not be an array");
244    static_assert(( is_standard_layout<value_type>::value), "Character type of basic_string_view must be standard-layout");
245    static_assert(( is_trivial<value_type>::value), "Character type of basic_string_view must be trivial");
246    static_assert((is_same<_CharT, typename traits_type::char_type>::value),
247                  "traits_type::char_type must be the same type as CharT");
248
249    // [string.view.cons], construct/copy
250    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
251    basic_string_view() _NOEXCEPT : __data (nullptr), __size(0) {}
252
253    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
254    basic_string_view(const basic_string_view&) _NOEXCEPT = default;
255
256    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
257    basic_string_view& operator=(const basic_string_view&) _NOEXCEPT = default;
258
259    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
260    basic_string_view(const _CharT* __s, size_type __len) _NOEXCEPT
261        : __data(__s), __size(__len)
262    {
263#if _LIBCPP_STD_VER > 11
264    _LIBCPP_ASSERT(__len == 0 || __s != nullptr, "string_view::string_view(_CharT *, size_t): received nullptr");
265#endif
266    }
267
268    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
269    basic_string_view(const _CharT* __s)
270        : __data(__s), __size(_VSTD::__char_traits_length_checked<_Traits>(__s)) {}
271
272    // [string.view.iterators], iterators
273    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
274    const_iterator begin()  const _NOEXCEPT { return cbegin(); }
275
276    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
277    const_iterator end()    const _NOEXCEPT { return cend(); }
278
279    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
280    const_iterator cbegin() const _NOEXCEPT { return __data; }
281
282    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
283    const_iterator cend()   const _NOEXCEPT { return __data + __size; }
284
285    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
286    const_reverse_iterator rbegin()   const _NOEXCEPT { return const_reverse_iterator(cend()); }
287
288    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
289    const_reverse_iterator rend()     const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
290
291    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
292    const_reverse_iterator crbegin()  const _NOEXCEPT { return const_reverse_iterator(cend()); }
293
294    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
295    const_reverse_iterator crend()    const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
296
297    // [string.view.capacity], capacity
298    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
299    size_type size()     const _NOEXCEPT { return __size; }
300
301    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
302    size_type length()   const _NOEXCEPT { return __size; }
303
304    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
305    size_type max_size() const _NOEXCEPT { return numeric_limits<size_type>::max(); }
306
307    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
308    bool empty()         const _NOEXCEPT { return __size == 0; }
309
310    // [string.view.access], element access
311    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
312    const_reference operator[](size_type __pos) const _NOEXCEPT {
313      return _LIBCPP_ASSERT(__pos < size(), "string_view[] index out of bounds"), __data[__pos];
314    }
315
316    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
317    const_reference at(size_type __pos) const
318    {
319        return __pos >= size()
320            ? (__throw_out_of_range("string_view::at"), __data[0])
321            : __data[__pos];
322    }
323
324    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
325    const_reference front() const _NOEXCEPT
326    {
327        return _LIBCPP_ASSERT(!empty(), "string_view::front(): string is empty"), __data[0];
328    }
329
330    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
331    const_reference back() const _NOEXCEPT
332    {
333        return _LIBCPP_ASSERT(!empty(), "string_view::back(): string is empty"), __data[__size-1];
334    }
335
336    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
337    const_pointer data() const _NOEXCEPT { return __data; }
338
339    // [string.view.modifiers], modifiers:
340    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
341    void remove_prefix(size_type __n) _NOEXCEPT
342    {
343        _LIBCPP_ASSERT(__n <= size(), "remove_prefix() can't remove more than size()");
344        __data += __n;
345        __size -= __n;
346    }
347
348    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
349    void remove_suffix(size_type __n) _NOEXCEPT
350    {
351        _LIBCPP_ASSERT(__n <= size(), "remove_suffix() can't remove more than size()");
352        __size -= __n;
353    }
354
355    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
356    void swap(basic_string_view& __other) _NOEXCEPT
357    {
358        const value_type *__p = __data;
359        __data = __other.__data;
360        __other.__data = __p;
361
362        size_type __sz = __size;
363        __size = __other.__size;
364        __other.__size = __sz;
365    }
366
367    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
368    size_type copy(_CharT* __s, size_type __n, size_type __pos = 0) const
369    {
370        if (__pos > size())
371            __throw_out_of_range("string_view::copy");
372        size_type __rlen = _VSTD::min(__n, size() - __pos);
373        _Traits::copy(__s, data() + __pos, __rlen);
374        return __rlen;
375    }
376
377    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
378    basic_string_view substr(size_type __pos = 0, size_type __n = npos) const
379    {
380        return __pos > size()
381            ? (__throw_out_of_range("string_view::substr"), basic_string_view())
382            : basic_string_view(data() + __pos, _VSTD::min(__n, size() - __pos));
383    }
384
385    _LIBCPP_CONSTEXPR_AFTER_CXX11 int compare(basic_string_view __sv) const _NOEXCEPT
386    {
387        size_type __rlen = _VSTD::min( size(), __sv.size());
388        int __retval = _Traits::compare(data(), __sv.data(), __rlen);
389        if ( __retval == 0 ) // first __rlen chars matched
390            __retval = size() == __sv.size() ? 0 : ( size() < __sv.size() ? -1 : 1 );
391        return __retval;
392    }
393
394    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
395    int compare(size_type __pos1, size_type __n1, basic_string_view __sv) const
396    {
397        return substr(__pos1, __n1).compare(__sv);
398    }
399
400    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
401    int compare(                       size_type __pos1, size_type __n1,
402                basic_string_view __sv, size_type __pos2, size_type __n2) const
403    {
404        return substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
405    }
406
407    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
408    int compare(const _CharT* __s) const _NOEXCEPT
409    {
410        return compare(basic_string_view(__s));
411    }
412
413    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
414    int compare(size_type __pos1, size_type __n1, const _CharT* __s) const
415    {
416        return substr(__pos1, __n1).compare(basic_string_view(__s));
417    }
418
419    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
420    int compare(size_type __pos1, size_type __n1, const _CharT* __s, size_type __n2) const
421    {
422        return substr(__pos1, __n1).compare(basic_string_view(__s, __n2));
423    }
424
425    // find
426    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
427    size_type find(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
428    {
429        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
430        return __str_find<value_type, size_type, traits_type, npos>
431            (data(), size(), __s.data(), __pos, __s.size());
432    }
433
434    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
435    size_type find(_CharT __c, size_type __pos = 0) const _NOEXCEPT
436    {
437        return __str_find<value_type, size_type, traits_type, npos>
438            (data(), size(), __c, __pos);
439    }
440
441    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
442    size_type find(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
443    {
444        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find(): received nullptr");
445        return __str_find<value_type, size_type, traits_type, npos>
446            (data(), size(), __s, __pos, __n);
447    }
448
449    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
450    size_type find(const _CharT* __s, size_type __pos = 0) const _NOEXCEPT
451    {
452        _LIBCPP_ASSERT(__s != nullptr, "string_view::find(): received nullptr");
453        return __str_find<value_type, size_type, traits_type, npos>
454            (data(), size(), __s, __pos, traits_type::length(__s));
455    }
456
457    // rfind
458    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
459    size_type rfind(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT
460    {
461        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
462        return __str_rfind<value_type, size_type, traits_type, npos>
463            (data(), size(), __s.data(), __pos, __s.size());
464    }
465
466    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
467    size_type rfind(_CharT __c, size_type __pos = npos) const _NOEXCEPT
468    {
469        return __str_rfind<value_type, size_type, traits_type, npos>
470            (data(), size(), __c, __pos);
471    }
472
473    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
474    size_type rfind(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
475    {
476        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::rfind(): received nullptr");
477        return __str_rfind<value_type, size_type, traits_type, npos>
478            (data(), size(), __s, __pos, __n);
479    }
480
481    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
482    size_type rfind(const _CharT* __s, size_type __pos=npos) const _NOEXCEPT
483    {
484        _LIBCPP_ASSERT(__s != nullptr, "string_view::rfind(): received nullptr");
485        return __str_rfind<value_type, size_type, traits_type, npos>
486            (data(), size(), __s, __pos, traits_type::length(__s));
487    }
488
489    // find_first_of
490    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
491    size_type find_first_of(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
492    {
493        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_of(): received nullptr");
494        return __str_find_first_of<value_type, size_type, traits_type, npos>
495            (data(), size(), __s.data(), __pos, __s.size());
496    }
497
498    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
499    size_type find_first_of(_CharT __c, size_type __pos = 0) const _NOEXCEPT
500    { return find(__c, __pos); }
501
502    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
503    size_type find_first_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
504    {
505        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_first_of(): received nullptr");
506        return __str_find_first_of<value_type, size_type, traits_type, npos>
507            (data(), size(), __s, __pos, __n);
508    }
509
510    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
511    size_type find_first_of(const _CharT* __s, size_type __pos=0) const _NOEXCEPT
512    {
513        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_of(): received nullptr");
514        return __str_find_first_of<value_type, size_type, traits_type, npos>
515            (data(), size(), __s, __pos, traits_type::length(__s));
516    }
517
518    // find_last_of
519    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
520    size_type find_last_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
521    {
522        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_of(): received nullptr");
523        return __str_find_last_of<value_type, size_type, traits_type, npos>
524            (data(), size(), __s.data(), __pos, __s.size());
525    }
526
527    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
528    size_type find_last_of(_CharT __c, size_type __pos = npos) const _NOEXCEPT
529    { return rfind(__c, __pos); }
530
531    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
532    size_type find_last_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
533    {
534        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_last_of(): received nullptr");
535        return __str_find_last_of<value_type, size_type, traits_type, npos>
536            (data(), size(), __s, __pos, __n);
537    }
538
539    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
540    size_type find_last_of(const _CharT* __s, size_type __pos=npos) const _NOEXCEPT
541    {
542        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_of(): received nullptr");
543        return __str_find_last_of<value_type, size_type, traits_type, npos>
544            (data(), size(), __s, __pos, traits_type::length(__s));
545    }
546
547    // find_first_not_of
548    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
549    size_type find_first_not_of(basic_string_view __s, size_type __pos=0) const _NOEXCEPT
550    {
551        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_not_of(): received nullptr");
552        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
553            (data(), size(), __s.data(), __pos, __s.size());
554    }
555
556    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
557    size_type find_first_not_of(_CharT __c, size_type __pos=0) const _NOEXCEPT
558    {
559        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
560            (data(), size(), __c, __pos);
561    }
562
563    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
564    size_type find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
565    {
566        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_first_not_of(): received nullptr");
567        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
568            (data(), size(), __s, __pos, __n);
569    }
570
571    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
572    size_type find_first_not_of(const _CharT* __s, size_type __pos=0) const _NOEXCEPT
573    {
574        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_not_of(): received nullptr");
575        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
576            (data(), size(), __s, __pos, traits_type::length(__s));
577    }
578
579    // find_last_not_of
580    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
581    size_type find_last_not_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
582    {
583        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_not_of(): received nullptr");
584        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
585            (data(), size(), __s.data(), __pos, __s.size());
586    }
587
588    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
589    size_type find_last_not_of(_CharT __c, size_type __pos=npos) const _NOEXCEPT
590    {
591        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
592            (data(), size(), __c, __pos);
593    }
594
595    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
596    size_type find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const _NOEXCEPT
597    {
598        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_last_not_of(): received nullptr");
599        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
600            (data(), size(), __s, __pos, __n);
601    }
602
603    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
604    size_type find_last_not_of(const _CharT* __s, size_type __pos=npos) const _NOEXCEPT
605    {
606        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_not_of(): received nullptr");
607        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
608            (data(), size(), __s, __pos, traits_type::length(__s));
609    }
610
611#if _LIBCPP_STD_VER > 17
612    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
613    bool starts_with(basic_string_view __s) const _NOEXCEPT
614    { return size() >= __s.size() && compare(0, __s.size(), __s) == 0; }
615
616    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
617    bool starts_with(value_type __c) const _NOEXCEPT
618    { return !empty() && _Traits::eq(front(), __c); }
619
620    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
621    bool starts_with(const value_type* __s) const _NOEXCEPT
622    { return starts_with(basic_string_view(__s)); }
623
624    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
625    bool ends_with(basic_string_view __s) const _NOEXCEPT
626    { return size() >= __s.size() && compare(size() - __s.size(), npos, __s) == 0; }
627
628    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
629    bool ends_with(value_type __c) const _NOEXCEPT
630    { return !empty() && _Traits::eq(back(), __c); }
631
632    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
633    bool ends_with(const value_type* __s) const _NOEXCEPT
634    { return ends_with(basic_string_view(__s)); }
635#endif
636
637#if _LIBCPP_STD_VER > 20
638    constexpr _LIBCPP_INLINE_VISIBILITY
639    bool contains(basic_string_view __sv) const noexcept
640    { return find(__sv) != npos; }
641
642    constexpr _LIBCPP_INLINE_VISIBILITY
643    bool contains(value_type __c) const noexcept
644    { return find(__c) != npos; }
645
646    constexpr _LIBCPP_INLINE_VISIBILITY
647    bool contains(const value_type* __s) const
648    { return find(__s) != npos; }
649#endif
650
651private:
652    const   value_type* __data;
653    size_type           __size;
654};
655
656#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_RANGES)
657template <class _CharT, class _Traits>
658inline constexpr bool ranges::enable_borrowed_range<basic_string_view<_CharT, _Traits> > = true;
659#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_RANGES)
660
661// [string.view.comparison]
662// operator ==
663template<class _CharT, class _Traits>
664_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
665bool operator==(basic_string_view<_CharT, _Traits> __lhs,
666                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
667{
668    if ( __lhs.size() != __rhs.size()) return false;
669    return __lhs.compare(__rhs) == 0;
670}
671
672template<class _CharT, class _Traits>
673_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
674bool operator==(basic_string_view<_CharT, _Traits> __lhs,
675                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
676{
677    if ( __lhs.size() != __rhs.size()) return false;
678    return __lhs.compare(__rhs) == 0;
679}
680
681template<class _CharT, class _Traits>
682_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
683bool operator==(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
684                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
685{
686    if ( __lhs.size() != __rhs.size()) return false;
687    return __lhs.compare(__rhs) == 0;
688}
689
690
691// operator !=
692template<class _CharT, class _Traits>
693_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
694bool operator!=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
695{
696    if ( __lhs.size() != __rhs.size())
697        return true;
698    return __lhs.compare(__rhs) != 0;
699}
700
701template<class _CharT, class _Traits>
702_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
703bool operator!=(basic_string_view<_CharT, _Traits> __lhs,
704                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
705{
706    if ( __lhs.size() != __rhs.size())
707        return true;
708    return __lhs.compare(__rhs) != 0;
709}
710
711template<class _CharT, class _Traits>
712_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
713bool operator!=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
714                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
715{
716    if ( __lhs.size() != __rhs.size())
717        return true;
718    return __lhs.compare(__rhs) != 0;
719}
720
721
722// operator <
723template<class _CharT, class _Traits>
724_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
725bool operator<(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
726{
727    return __lhs.compare(__rhs) < 0;
728}
729
730template<class _CharT, class _Traits>
731_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
732bool operator<(basic_string_view<_CharT, _Traits> __lhs,
733                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
734{
735    return __lhs.compare(__rhs) < 0;
736}
737
738template<class _CharT, class _Traits>
739_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
740bool operator<(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
741                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
742{
743    return __lhs.compare(__rhs) < 0;
744}
745
746
747// operator >
748template<class _CharT, class _Traits>
749_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
750bool operator> (basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
751{
752    return __lhs.compare(__rhs) > 0;
753}
754
755template<class _CharT, class _Traits>
756_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
757bool operator>(basic_string_view<_CharT, _Traits> __lhs,
758                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
759{
760    return __lhs.compare(__rhs) > 0;
761}
762
763template<class _CharT, class _Traits>
764_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
765bool operator>(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
766                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
767{
768    return __lhs.compare(__rhs) > 0;
769}
770
771
772// operator <=
773template<class _CharT, class _Traits>
774_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
775bool operator<=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
776{
777    return __lhs.compare(__rhs) <= 0;
778}
779
780template<class _CharT, class _Traits>
781_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
782bool operator<=(basic_string_view<_CharT, _Traits> __lhs,
783                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
784{
785    return __lhs.compare(__rhs) <= 0;
786}
787
788template<class _CharT, class _Traits>
789_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
790bool operator<=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
791                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
792{
793    return __lhs.compare(__rhs) <= 0;
794}
795
796
797// operator >=
798template<class _CharT, class _Traits>
799_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
800bool operator>=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
801{
802    return __lhs.compare(__rhs) >= 0;
803}
804
805
806template<class _CharT, class _Traits>
807_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
808bool operator>=(basic_string_view<_CharT, _Traits> __lhs,
809                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
810{
811    return __lhs.compare(__rhs) >= 0;
812}
813
814template<class _CharT, class _Traits>
815_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
816bool operator>=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
817                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
818{
819    return __lhs.compare(__rhs) >= 0;
820}
821
822
823template<class _CharT, class _Traits>
824basic_ostream<_CharT, _Traits>&
825operator<<(basic_ostream<_CharT, _Traits>& __os,
826           basic_string_view<_CharT, _Traits> __str);
827
828// [string.view.hash]
829template<class _CharT>
830struct _LIBCPP_TEMPLATE_VIS hash<basic_string_view<_CharT, char_traits<_CharT> > >
831    : public unary_function<basic_string_view<_CharT, char_traits<_CharT> >, size_t>
832{
833    _LIBCPP_INLINE_VISIBILITY
834    size_t operator()(const basic_string_view<_CharT, char_traits<_CharT> > __val) const _NOEXCEPT {
835        return __do_string_hash(__val.data(), __val.data() + __val.size());
836    }
837};
838
839
840#if _LIBCPP_STD_VER > 11
841inline namespace literals
842{
843  inline namespace string_view_literals
844  {
845    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
846    basic_string_view<char> operator "" sv(const char *__str, size_t __len) _NOEXCEPT
847    {
848        return basic_string_view<char> (__str, __len);
849    }
850
851    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
852    basic_string_view<wchar_t> operator "" sv(const wchar_t *__str, size_t __len) _NOEXCEPT
853    {
854        return basic_string_view<wchar_t> (__str, __len);
855    }
856
857#ifndef _LIBCPP_HAS_NO_CHAR8_T
858    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
859    basic_string_view<char8_t> operator "" sv(const char8_t *__str, size_t __len) _NOEXCEPT
860    {
861        return basic_string_view<char8_t> (__str, __len);
862    }
863#endif
864
865    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
866    basic_string_view<char16_t> operator "" sv(const char16_t *__str, size_t __len) _NOEXCEPT
867    {
868        return basic_string_view<char16_t> (__str, __len);
869    }
870
871    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
872    basic_string_view<char32_t> operator "" sv(const char32_t *__str, size_t __len) _NOEXCEPT
873    {
874        return basic_string_view<char32_t> (__str, __len);
875    }
876  }
877}
878#endif
879_LIBCPP_END_NAMESPACE_STD
880
881_LIBCPP_POP_MACROS
882
883#endif // _LIBCPP_STRING_VIEW
884