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    // 7.9, basic_string_view non-member comparison functions
23    template<class charT, class traits>
24    constexpr bool operator==(basic_string_view<charT, traits> x,
25                              basic_string_view<charT, traits> y) noexcept;
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    // see below, sufficient additional overloads of comparison functions
42
43    // 7.10, Inserters and extractors
44    template<class charT, class traits>
45      basic_ostream<charT, traits>&
46        operator<<(basic_ostream<charT, traits>& os,
47                   basic_string_view<charT, traits> str);
48
49    // basic_string_view typedef names
50    typedef basic_string_view<char> string_view;
51    typedef basic_string_view<char16_t> u16string_view;
52    typedef basic_string_view<char32_t> u32string_view;
53    typedef basic_string_view<wchar_t> wstring_view;
54
55    template<class charT, class traits = char_traits<charT>>
56    class basic_string_view {
57      public:
58      // types
59      typedef traits traits_type;
60      typedef charT value_type;
61      typedef charT* pointer;
62      typedef const charT* const_pointer;
63      typedef charT& reference;
64      typedef const charT& const_reference;
65      typedef implementation-defined const_iterator;
66      typedef const_iterator iterator;
67      typedef reverse_iterator<const_iterator> const_reverse_iterator;
68      typedef const_reverse_iterator reverse_iterator;
69      typedef size_t size_type;
70      typedef ptrdiff_t difference_type;
71      static constexpr size_type npos = size_type(-1);
72
73      // 7.3, basic_string_view constructors and assignment operators
74      constexpr basic_string_view() noexcept;
75      constexpr basic_string_view(const basic_string_view&) noexcept = default;
76      basic_string_view& operator=(const basic_string_view&) noexcept = default;
77      template<class Allocator>
78      constexpr basic_string_view(const charT* str);
79      constexpr basic_string_view(const charT* str, size_type len);
80
81      // 7.4, basic_string_view iterator support
82      constexpr const_iterator begin() const noexcept;
83      constexpr const_iterator end() const noexcept;
84      constexpr const_iterator cbegin() const noexcept;
85      constexpr const_iterator cend() const noexcept;
86      const_reverse_iterator rbegin() const noexcept;
87      const_reverse_iterator rend() const noexcept;
88      const_reverse_iterator crbegin() const noexcept;
89      const_reverse_iterator crend() const noexcept;
90
91      // 7.5, basic_string_view capacity
92      constexpr size_type size() const noexcept;
93      constexpr size_type length() const noexcept;
94      constexpr size_type max_size() const noexcept;
95      constexpr bool empty() const noexcept;
96
97      // 7.6, basic_string_view element access
98      constexpr const_reference operator[](size_type pos) const;
99      constexpr const_reference at(size_type pos) const;
100      constexpr const_reference front() const;
101      constexpr const_reference back() const;
102      constexpr const_pointer data() const noexcept;
103
104      // 7.7, basic_string_view modifiers
105      constexpr void remove_prefix(size_type n);
106      constexpr void remove_suffix(size_type n);
107      constexpr void swap(basic_string_view& s) noexcept;
108
109      size_type copy(charT* s, size_type n, size_type pos = 0) const;
110
111      constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const;
112      constexpr int compare(basic_string_view s) const noexcept;
113      constexpr int compare(size_type pos1, size_type n1, basic_string_view s) const;
114      constexpr int compare(size_type pos1, size_type n1,
115                            basic_string_view s, size_type pos2, size_type n2) const;
116      constexpr int compare(const charT* s) const;
117      constexpr int compare(size_type pos1, size_type n1, const charT* s) const;
118      constexpr int compare(size_type pos1, size_type n1,
119                            const charT* s, size_type n2) const;
120      constexpr size_type find(basic_string_view s, size_type pos = 0) const noexcept;
121      constexpr size_type find(charT c, size_type pos = 0) const noexcept;
122      constexpr size_type find(const charT* s, size_type pos, size_type n) const;
123      constexpr size_type find(const charT* s, size_type pos = 0) const;
124      constexpr size_type rfind(basic_string_view s, size_type pos = npos) const noexcept;
125      constexpr size_type rfind(charT c, size_type pos = npos) const noexcept;
126      constexpr size_type rfind(const charT* s, size_type pos, size_type n) const;
127      constexpr size_type rfind(const charT* s, size_type pos = npos) const;
128      constexpr size_type find_first_of(basic_string_view s, size_type pos = 0) const noexcept;
129      constexpr size_type find_first_of(charT c, size_type pos = 0) const noexcept;
130      constexpr size_type find_first_of(const charT* s, size_type pos, size_type n) const;
131      constexpr size_type find_first_of(const charT* s, size_type pos = 0) const;
132      constexpr size_type find_last_of(basic_string_view s, size_type pos = npos) const noexcept;
133      constexpr size_type find_last_of(charT c, size_type pos = npos) const noexcept;
134      constexpr size_type find_last_of(const charT* s, size_type pos, size_type n) const;
135      constexpr size_type find_last_of(const charT* s, size_type pos = npos) const;
136      constexpr size_type find_first_not_of(basic_string_view s, size_type pos = 0) const noexcept;
137      constexpr size_type find_first_not_of(charT c, size_type pos = 0) const noexcept;
138      constexpr size_type find_first_not_of(const charT* s, size_type pos, size_type n) const;
139      constexpr size_type find_first_not_of(const charT* s, size_type pos = 0) const;
140      constexpr size_type find_last_not_of(basic_string_view s, size_type pos = npos) const noexcept;
141      constexpr size_type find_last_not_of(charT c, size_type pos = npos) const noexcept;
142      constexpr size_type find_last_not_of(const charT* s, size_type pos, size_type n) const;
143      constexpr size_type find_last_not_of(const charT* s, size_type pos = npos) const;
144
145      constexpr bool starts_with(basic_string_view s) const noexcept; // C++2a
146      constexpr bool starts_with(charT c) const noexcept;             // C++2a
147      constexpr bool starts_with(const charT* s) const;               // C++2a
148      constexpr bool ends_with(basic_string_view s) const noexcept;   // C++2a
149      constexpr bool ends_with(charT c) const noexcept;               // C++2a
150      constexpr bool ends_with(const charT* s) const;                 // C++2a
151
152     private:
153      const_pointer data_;  // exposition only
154      size_type     size_;  // exposition only
155    };
156
157  // 7.11, Hash support
158  template <class T> struct hash;
159  template <> struct hash<string_view>;
160  template <> struct hash<u16string_view>;
161  template <> struct hash<u32string_view>;
162  template <> struct hash<wstring_view>;
163
164  constexpr basic_string_view<char>     operator "" sv( const char *str,     size_t len ) noexcept;
165  constexpr basic_string_view<wchar_t>  operator "" sv( const wchar_t *str,  size_t len ) noexcept;
166  constexpr basic_string_view<char16_t> operator "" sv( const char16_t *str, size_t len ) noexcept;
167  constexpr basic_string_view<char32_t> operator "" sv( const char32_t *str, size_t len ) noexcept;
168
169}  // namespace std
170
171
172*/
173
174#include <__config>
175#include <__string>
176#include <iosfwd>
177#include <algorithm>
178#include <iterator>
179#include <limits>
180#include <stdexcept>
181#include <version>
182#include <__debug>
183
184#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
185#pragma GCC system_header
186#endif
187
188_LIBCPP_PUSH_MACROS
189#include <__undef_macros>
190
191
192_LIBCPP_BEGIN_NAMESPACE_STD
193
194template<class _CharT, class _Traits = char_traits<_CharT> >
195    class _LIBCPP_TEMPLATE_VIS basic_string_view;
196
197typedef basic_string_view<char>     string_view;
198#ifndef _LIBCPP_NO_HAS_CHAR8_T
199typedef basic_string_view<char8_t>  u8string_view;
200#endif
201typedef basic_string_view<char16_t> u16string_view;
202typedef basic_string_view<char32_t> u32string_view;
203typedef basic_string_view<wchar_t>  wstring_view;
204
205template<class _CharT, class _Traits>
206class
207    _LIBCPP_PREFERRED_NAME(string_view)
208#ifndef _LIBCPP_NO_HAS_CHAR8_T
209    _LIBCPP_PREFERRED_NAME(u8string_view)
210#endif
211    _LIBCPP_PREFERRED_NAME(u16string_view)
212    _LIBCPP_PREFERRED_NAME(u32string_view)
213    _LIBCPP_PREFERRED_NAME(wstring_view)
214    basic_string_view {
215public:
216    // types
217    typedef _Traits                                    traits_type;
218    typedef _CharT                                     value_type;
219    typedef _CharT*                                    pointer;
220    typedef const _CharT*                              const_pointer;
221    typedef _CharT&                                    reference;
222    typedef const _CharT&                              const_reference;
223    typedef const_pointer                              const_iterator; // See [string.view.iterators]
224    typedef const_iterator                             iterator;
225    typedef _VSTD::reverse_iterator<const_iterator>    const_reverse_iterator;
226    typedef const_reverse_iterator                     reverse_iterator;
227    typedef size_t                                     size_type;
228    typedef ptrdiff_t                                  difference_type;
229    static _LIBCPP_CONSTEXPR const size_type npos = -1; // size_type(-1);
230
231    static_assert((!is_array<value_type>::value), "Character type of basic_string_view must not be an array");
232    static_assert(( is_standard_layout<value_type>::value), "Character type of basic_string_view must be standard-layout");
233    static_assert(( is_trivial<value_type>::value), "Character type of basic_string_view must be trivial");
234    static_assert((is_same<_CharT, typename traits_type::char_type>::value),
235                  "traits_type::char_type must be the same type as CharT");
236
237    // [string.view.cons], construct/copy
238    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
239    basic_string_view() _NOEXCEPT : __data (nullptr), __size(0) {}
240
241    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
242    basic_string_view(const basic_string_view&) _NOEXCEPT = default;
243
244    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
245    basic_string_view& operator=(const basic_string_view&) _NOEXCEPT = default;
246
247    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
248    basic_string_view(const _CharT* __s, size_type __len) _NOEXCEPT
249        : __data(__s), __size(__len)
250    {
251#if _LIBCPP_STD_VER > 11
252    _LIBCPP_ASSERT(__len == 0 || __s != nullptr, "string_view::string_view(_CharT *, size_t): received nullptr");
253#endif
254    }
255
256    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
257    basic_string_view(const _CharT* __s)
258        : __data(__s), __size(_VSTD::__char_traits_length_checked<_Traits>(__s)) {}
259
260    // [string.view.iterators], iterators
261    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
262    const_iterator begin()  const _NOEXCEPT { return cbegin(); }
263
264    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
265    const_iterator end()    const _NOEXCEPT { return cend(); }
266
267    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
268    const_iterator cbegin() const _NOEXCEPT { return __data; }
269
270    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
271    const_iterator cend()   const _NOEXCEPT { return __data + __size; }
272
273    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
274    const_reverse_iterator rbegin()   const _NOEXCEPT { return const_reverse_iterator(cend()); }
275
276    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
277    const_reverse_iterator rend()     const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
278
279    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
280    const_reverse_iterator crbegin()  const _NOEXCEPT { return const_reverse_iterator(cend()); }
281
282    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
283    const_reverse_iterator crend()    const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
284
285    // [string.view.capacity], capacity
286    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
287    size_type size()     const _NOEXCEPT { return __size; }
288
289    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
290    size_type length()   const _NOEXCEPT { return __size; }
291
292    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
293    size_type max_size() const _NOEXCEPT { return numeric_limits<size_type>::max(); }
294
295    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
296    bool empty()         const _NOEXCEPT { return __size == 0; }
297
298    // [string.view.access], element access
299    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
300    const_reference operator[](size_type __pos) const _NOEXCEPT {
301      return _LIBCPP_ASSERT(__pos < size(), "string_view[] index out of bounds"), __data[__pos];
302    }
303
304    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
305    const_reference at(size_type __pos) const
306    {
307        return __pos >= size()
308            ? (__throw_out_of_range("string_view::at"), __data[0])
309            : __data[__pos];
310    }
311
312    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
313    const_reference front() const _NOEXCEPT
314    {
315        return _LIBCPP_ASSERT(!empty(), "string_view::front(): string is empty"), __data[0];
316    }
317
318    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
319    const_reference back() const _NOEXCEPT
320    {
321        return _LIBCPP_ASSERT(!empty(), "string_view::back(): string is empty"), __data[__size-1];
322    }
323
324    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
325    const_pointer data() const _NOEXCEPT { return __data; }
326
327    // [string.view.modifiers], modifiers:
328    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
329    void remove_prefix(size_type __n) _NOEXCEPT
330    {
331        _LIBCPP_ASSERT(__n <= size(), "remove_prefix() can't remove more than size()");
332        __data += __n;
333        __size -= __n;
334    }
335
336    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
337    void remove_suffix(size_type __n) _NOEXCEPT
338    {
339        _LIBCPP_ASSERT(__n <= size(), "remove_suffix() can't remove more than size()");
340        __size -= __n;
341    }
342
343    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
344    void swap(basic_string_view& __other) _NOEXCEPT
345    {
346        const value_type *__p = __data;
347        __data = __other.__data;
348        __other.__data = __p;
349
350        size_type __sz = __size;
351        __size = __other.__size;
352        __other.__size = __sz;
353    }
354
355    _LIBCPP_INLINE_VISIBILITY
356    size_type copy(_CharT* __s, size_type __n, size_type __pos = 0) const
357    {
358        if (__pos > size())
359            __throw_out_of_range("string_view::copy");
360        size_type __rlen = _VSTD::min(__n, size() - __pos);
361        _Traits::copy(__s, data() + __pos, __rlen);
362        return __rlen;
363    }
364
365    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
366    basic_string_view substr(size_type __pos = 0, size_type __n = npos) const
367    {
368        return __pos > size()
369            ? (__throw_out_of_range("string_view::substr"), basic_string_view())
370            : basic_string_view(data() + __pos, _VSTD::min(__n, size() - __pos));
371    }
372
373    _LIBCPP_CONSTEXPR_AFTER_CXX11 int compare(basic_string_view __sv) const _NOEXCEPT
374    {
375        size_type __rlen = _VSTD::min( size(), __sv.size());
376        int __retval = _Traits::compare(data(), __sv.data(), __rlen);
377        if ( __retval == 0 ) // first __rlen chars matched
378            __retval = size() == __sv.size() ? 0 : ( size() < __sv.size() ? -1 : 1 );
379        return __retval;
380    }
381
382    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
383    int compare(size_type __pos1, size_type __n1, basic_string_view __sv) const
384    {
385        return substr(__pos1, __n1).compare(__sv);
386    }
387
388    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
389    int compare(                       size_type __pos1, size_type __n1,
390                basic_string_view __sv, size_type __pos2, size_type __n2) const
391    {
392        return substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
393    }
394
395    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
396    int compare(const _CharT* __s) const _NOEXCEPT
397    {
398        return compare(basic_string_view(__s));
399    }
400
401    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
402    int compare(size_type __pos1, size_type __n1, const _CharT* __s) const
403    {
404        return substr(__pos1, __n1).compare(basic_string_view(__s));
405    }
406
407    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
408    int compare(size_type __pos1, size_type __n1, const _CharT* __s, size_type __n2) const
409    {
410        return substr(__pos1, __n1).compare(basic_string_view(__s, __n2));
411    }
412
413    // find
414    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
415    size_type find(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
416    {
417        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
418        return __str_find<value_type, size_type, traits_type, npos>
419            (data(), size(), __s.data(), __pos, __s.size());
420    }
421
422    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
423    size_type find(_CharT __c, size_type __pos = 0) const _NOEXCEPT
424    {
425        return __str_find<value_type, size_type, traits_type, npos>
426            (data(), size(), __c, __pos);
427    }
428
429    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
430    size_type find(const _CharT* __s, size_type __pos, size_type __n) const
431    {
432        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find(): received nullptr");
433        return __str_find<value_type, size_type, traits_type, npos>
434            (data(), size(), __s, __pos, __n);
435    }
436
437    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
438    size_type find(const _CharT* __s, size_type __pos = 0) const
439    {
440        _LIBCPP_ASSERT(__s != nullptr, "string_view::find(): received nullptr");
441        return __str_find<value_type, size_type, traits_type, npos>
442            (data(), size(), __s, __pos, traits_type::length(__s));
443    }
444
445    // rfind
446    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
447    size_type rfind(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT
448    {
449        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
450        return __str_rfind<value_type, size_type, traits_type, npos>
451            (data(), size(), __s.data(), __pos, __s.size());
452    }
453
454    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
455    size_type rfind(_CharT __c, size_type __pos = npos) const _NOEXCEPT
456    {
457        return __str_rfind<value_type, size_type, traits_type, npos>
458            (data(), size(), __c, __pos);
459    }
460
461    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
462    size_type rfind(const _CharT* __s, size_type __pos, size_type __n) const
463    {
464        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::rfind(): received nullptr");
465        return __str_rfind<value_type, size_type, traits_type, npos>
466            (data(), size(), __s, __pos, __n);
467    }
468
469    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
470    size_type rfind(const _CharT* __s, size_type __pos=npos) const
471    {
472        _LIBCPP_ASSERT(__s != nullptr, "string_view::rfind(): received nullptr");
473        return __str_rfind<value_type, size_type, traits_type, npos>
474            (data(), size(), __s, __pos, traits_type::length(__s));
475    }
476
477    // find_first_of
478    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
479    size_type find_first_of(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
480    {
481        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_of(): received nullptr");
482        return __str_find_first_of<value_type, size_type, traits_type, npos>
483            (data(), size(), __s.data(), __pos, __s.size());
484    }
485
486    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
487    size_type find_first_of(_CharT __c, size_type __pos = 0) const _NOEXCEPT
488    { return find(__c, __pos); }
489
490    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
491    size_type find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
492    {
493        _LIBCPP_ASSERT(__n == 0 || __s != 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, __pos, __n);
496    }
497
498    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
499    size_type find_first_of(const _CharT* __s, size_type __pos=0) const
500    {
501        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_of(): received nullptr");
502        return __str_find_first_of<value_type, size_type, traits_type, npos>
503            (data(), size(), __s, __pos, traits_type::length(__s));
504    }
505
506    // find_last_of
507    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
508    size_type find_last_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
509    {
510        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_of(): received nullptr");
511        return __str_find_last_of<value_type, size_type, traits_type, npos>
512            (data(), size(), __s.data(), __pos, __s.size());
513    }
514
515    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
516    size_type find_last_of(_CharT __c, size_type __pos = npos) const _NOEXCEPT
517    { return rfind(__c, __pos); }
518
519    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
520    size_type find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
521    {
522        _LIBCPP_ASSERT(__n == 0 || __s != 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, __pos, __n);
525    }
526
527    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
528    size_type find_last_of(const _CharT* __s, size_type __pos=npos) const
529    {
530        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_of(): received nullptr");
531        return __str_find_last_of<value_type, size_type, traits_type, npos>
532            (data(), size(), __s, __pos, traits_type::length(__s));
533    }
534
535    // find_first_not_of
536    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
537    size_type find_first_not_of(basic_string_view __s, size_type __pos=0) const _NOEXCEPT
538    {
539        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_not_of(): received nullptr");
540        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
541            (data(), size(), __s.data(), __pos, __s.size());
542    }
543
544    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
545    size_type find_first_not_of(_CharT __c, size_type __pos=0) const _NOEXCEPT
546    {
547        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
548            (data(), size(), __c, __pos);
549    }
550
551    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
552    size_type find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
553    {
554        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_first_not_of(): received nullptr");
555        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
556            (data(), size(), __s, __pos, __n);
557    }
558
559    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
560    size_type find_first_not_of(const _CharT* __s, size_type __pos=0) const
561    {
562        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_not_of(): received nullptr");
563        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
564            (data(), size(), __s, __pos, traits_type::length(__s));
565    }
566
567    // find_last_not_of
568    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
569    size_type find_last_not_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
570    {
571        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_not_of(): received nullptr");
572        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
573            (data(), size(), __s.data(), __pos, __s.size());
574    }
575
576    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
577    size_type find_last_not_of(_CharT __c, size_type __pos=npos) const _NOEXCEPT
578    {
579        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
580            (data(), size(), __c, __pos);
581    }
582
583    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
584    size_type find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
585    {
586        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_last_not_of(): received nullptr");
587        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
588            (data(), size(), __s, __pos, __n);
589    }
590
591    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
592    size_type find_last_not_of(const _CharT* __s, size_type __pos=npos) const
593    {
594        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_not_of(): received nullptr");
595        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
596            (data(), size(), __s, __pos, traits_type::length(__s));
597    }
598
599#if _LIBCPP_STD_VER > 17
600    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
601    bool starts_with(basic_string_view __s) const _NOEXCEPT
602    { return size() >= __s.size() && compare(0, __s.size(), __s) == 0; }
603
604    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
605    bool starts_with(value_type __c) const _NOEXCEPT
606    { return !empty() && _Traits::eq(front(), __c); }
607
608    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
609    bool starts_with(const value_type* __s) const _NOEXCEPT
610    { return starts_with(basic_string_view(__s)); }
611
612    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
613    bool ends_with(basic_string_view __s) const _NOEXCEPT
614    { return size() >= __s.size() && compare(size() - __s.size(), npos, __s) == 0; }
615
616    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
617    bool ends_with(value_type __c) const _NOEXCEPT
618    { return !empty() && _Traits::eq(back(), __c); }
619
620    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
621    bool ends_with(const value_type* __s) const _NOEXCEPT
622    { return ends_with(basic_string_view(__s)); }
623#endif
624
625private:
626    const   value_type* __data;
627    size_type           __size;
628};
629
630
631// [string.view.comparison]
632// operator ==
633template<class _CharT, class _Traits>
634_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
635bool operator==(basic_string_view<_CharT, _Traits> __lhs,
636                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
637{
638    if ( __lhs.size() != __rhs.size()) return false;
639    return __lhs.compare(__rhs) == 0;
640}
641
642template<class _CharT, class _Traits>
643_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
644bool operator==(basic_string_view<_CharT, _Traits> __lhs,
645                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
646{
647    if ( __lhs.size() != __rhs.size()) return false;
648    return __lhs.compare(__rhs) == 0;
649}
650
651template<class _CharT, class _Traits>
652_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
653bool operator==(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
654                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
655{
656    if ( __lhs.size() != __rhs.size()) return false;
657    return __lhs.compare(__rhs) == 0;
658}
659
660
661// operator !=
662template<class _CharT, class _Traits>
663_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
664bool operator!=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
665{
666    if ( __lhs.size() != __rhs.size())
667        return true;
668    return __lhs.compare(__rhs) != 0;
669}
670
671template<class _CharT, class _Traits>
672_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
673bool operator!=(basic_string_view<_CharT, _Traits> __lhs,
674                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
675{
676    if ( __lhs.size() != __rhs.size())
677        return true;
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())
687        return true;
688    return __lhs.compare(__rhs) != 0;
689}
690
691
692// operator <
693template<class _CharT, class _Traits>
694_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
695bool operator<(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
696{
697    return __lhs.compare(__rhs) < 0;
698}
699
700template<class _CharT, class _Traits>
701_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
702bool operator<(basic_string_view<_CharT, _Traits> __lhs,
703                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
704{
705    return __lhs.compare(__rhs) < 0;
706}
707
708template<class _CharT, class _Traits>
709_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
710bool operator<(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
711                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
712{
713    return __lhs.compare(__rhs) < 0;
714}
715
716
717// operator >
718template<class _CharT, class _Traits>
719_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
720bool operator> (basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
721{
722    return __lhs.compare(__rhs) > 0;
723}
724
725template<class _CharT, class _Traits>
726_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
727bool operator>(basic_string_view<_CharT, _Traits> __lhs,
728                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
729{
730    return __lhs.compare(__rhs) > 0;
731}
732
733template<class _CharT, class _Traits>
734_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
735bool operator>(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
736                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
737{
738    return __lhs.compare(__rhs) > 0;
739}
740
741
742// operator <=
743template<class _CharT, class _Traits>
744_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
745bool operator<=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
746{
747    return __lhs.compare(__rhs) <= 0;
748}
749
750template<class _CharT, class _Traits>
751_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
752bool operator<=(basic_string_view<_CharT, _Traits> __lhs,
753                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
754{
755    return __lhs.compare(__rhs) <= 0;
756}
757
758template<class _CharT, class _Traits>
759_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
760bool operator<=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
761                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
762{
763    return __lhs.compare(__rhs) <= 0;
764}
765
766
767// operator >=
768template<class _CharT, class _Traits>
769_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
770bool operator>=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
771{
772    return __lhs.compare(__rhs) >= 0;
773}
774
775
776template<class _CharT, class _Traits>
777_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
778bool operator>=(basic_string_view<_CharT, _Traits> __lhs,
779                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
780{
781    return __lhs.compare(__rhs) >= 0;
782}
783
784template<class _CharT, class _Traits>
785_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
786bool operator>=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
787                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
788{
789    return __lhs.compare(__rhs) >= 0;
790}
791
792
793template<class _CharT, class _Traits>
794basic_ostream<_CharT, _Traits>&
795operator<<(basic_ostream<_CharT, _Traits>& __os,
796           basic_string_view<_CharT, _Traits> __str);
797
798// [string.view.hash]
799template<class _CharT>
800struct _LIBCPP_TEMPLATE_VIS hash<basic_string_view<_CharT, char_traits<_CharT> > >
801    : public unary_function<basic_string_view<_CharT, char_traits<_CharT> >, size_t>
802{
803    _LIBCPP_INLINE_VISIBILITY
804    size_t operator()(const basic_string_view<_CharT, char_traits<_CharT> > __val) const _NOEXCEPT {
805        return __do_string_hash(__val.data(), __val.data() + __val.size());
806    }
807};
808
809
810#if _LIBCPP_STD_VER > 11
811inline namespace literals
812{
813  inline namespace string_view_literals
814  {
815    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
816    basic_string_view<char> operator "" sv(const char *__str, size_t __len) _NOEXCEPT
817    {
818        return basic_string_view<char> (__str, __len);
819    }
820
821    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
822    basic_string_view<wchar_t> operator "" sv(const wchar_t *__str, size_t __len) _NOEXCEPT
823    {
824        return basic_string_view<wchar_t> (__str, __len);
825    }
826
827#ifndef _LIBCPP_NO_HAS_CHAR8_T
828    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
829    basic_string_view<char8_t> operator "" sv(const char8_t *__str, size_t __len) _NOEXCEPT
830    {
831        return basic_string_view<char8_t> (__str, __len);
832    }
833#endif
834
835    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
836    basic_string_view<char16_t> operator "" sv(const char16_t *__str, size_t __len) _NOEXCEPT
837    {
838        return basic_string_view<char16_t> (__str, __len);
839    }
840
841    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
842    basic_string_view<char32_t> operator "" sv(const char32_t *__str, size_t __len) _NOEXCEPT
843    {
844        return basic_string_view<char32_t> (__str, __len);
845    }
846  }
847}
848#endif
849_LIBCPP_END_NAMESPACE_STD
850
851_LIBCPP_POP_MACROS
852
853#endif // _LIBCPP_STRING_VIEW
854