string_view revision 360784 
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> >
195class _LIBCPP_TEMPLATE_VIS basic_string_view {
196public:
197    // types
198    typedef _Traits                                    traits_type;
199    typedef _CharT                                     value_type;
200    typedef _CharT*                                    pointer;
201    typedef const _CharT*                              const_pointer;
202    typedef _CharT&                                    reference;
203    typedef const _CharT&                              const_reference;
204    typedef const_pointer                              const_iterator; // See [string.view.iterators]
205    typedef const_iterator                             iterator;
206    typedef _VSTD::reverse_iterator<const_iterator>    const_reverse_iterator;
207    typedef const_reverse_iterator                     reverse_iterator;
208    typedef size_t                                     size_type;
209    typedef ptrdiff_t                                  difference_type;
210    static _LIBCPP_CONSTEXPR const size_type npos = -1; // size_type(-1);
211
212    static_assert((!is_array<value_type>::value), "Character type of basic_string_view must not be an array");
213    static_assert(( is_standard_layout<value_type>::value), "Character type of basic_string_view must be standard-layout");
214    static_assert(( is_trivial<value_type>::value), "Character type of basic_string_view must be trivial");
215    static_assert((is_same<_CharT, typename traits_type::char_type>::value),
216                  "traits_type::char_type must be the same type as CharT");
217
218    // [string.view.cons], construct/copy
219    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
220    basic_string_view() _NOEXCEPT : __data (nullptr), __size(0) {}
221
222    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
223    basic_string_view(const basic_string_view&) _NOEXCEPT = default;
224
225    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
226    basic_string_view& operator=(const basic_string_view&) _NOEXCEPT = default;
227
228    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
229    basic_string_view(const _CharT* __s, size_type __len) _NOEXCEPT
230        : __data(__s), __size(__len)
231    {
232#if _LIBCPP_STD_VER > 11
233    _LIBCPP_ASSERT(__len == 0 || __s != nullptr, "string_view::string_view(_CharT *, size_t): received nullptr");
234#endif
235    }
236
237    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
238    basic_string_view(const _CharT* __s)
239        : __data(__s), __size(std::__char_traits_length_checked<_Traits>(__s)) {}
240
241    // [string.view.iterators], iterators
242    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
243    const_iterator begin()  const _NOEXCEPT { return cbegin(); }
244
245    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
246    const_iterator end()    const _NOEXCEPT { return cend(); }
247
248    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
249    const_iterator cbegin() const _NOEXCEPT { return __data; }
250
251    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
252    const_iterator cend()   const _NOEXCEPT { return __data + __size; }
253
254    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
255    const_reverse_iterator rbegin()   const _NOEXCEPT { return const_reverse_iterator(cend()); }
256
257    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
258    const_reverse_iterator rend()     const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
259
260    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
261    const_reverse_iterator crbegin()  const _NOEXCEPT { return const_reverse_iterator(cend()); }
262
263    _LIBCPP_CONSTEXPR_AFTER_CXX14 _LIBCPP_INLINE_VISIBILITY
264    const_reverse_iterator crend()    const _NOEXCEPT { return const_reverse_iterator(cbegin()); }
265
266    // [string.view.capacity], capacity
267    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
268    size_type size()     const _NOEXCEPT { return __size; }
269
270    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
271    size_type length()   const _NOEXCEPT { return __size; }
272
273    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
274    size_type max_size() const _NOEXCEPT { return numeric_limits<size_type>::max(); }
275
276    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
277    bool empty()         const _NOEXCEPT { return __size == 0; }
278
279    // [string.view.access], element access
280    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
281    const_reference operator[](size_type __pos) const _NOEXCEPT { return __data[__pos]; }
282
283    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
284    const_reference at(size_type __pos) const
285    {
286        return __pos >= size()
287            ? (__throw_out_of_range("string_view::at"), __data[0])
288            : __data[__pos];
289    }
290
291    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
292    const_reference front() const _NOEXCEPT
293    {
294        return _LIBCPP_ASSERT(!empty(), "string_view::front(): string is empty"), __data[0];
295    }
296
297    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
298    const_reference back() const _NOEXCEPT
299    {
300        return _LIBCPP_ASSERT(!empty(), "string_view::back(): string is empty"), __data[__size-1];
301    }
302
303    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
304    const_pointer data() const _NOEXCEPT { return __data; }
305
306    // [string.view.modifiers], modifiers:
307    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
308    void remove_prefix(size_type __n) _NOEXCEPT
309    {
310        _LIBCPP_ASSERT(__n <= size(), "remove_prefix() can't remove more than size()");
311        __data += __n;
312        __size -= __n;
313    }
314
315    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
316    void remove_suffix(size_type __n) _NOEXCEPT
317    {
318        _LIBCPP_ASSERT(__n <= size(), "remove_suffix() can't remove more than size()");
319        __size -= __n;
320    }
321
322    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
323    void swap(basic_string_view& __other) _NOEXCEPT
324    {
325        const value_type *__p = __data;
326        __data = __other.__data;
327        __other.__data = __p;
328
329        size_type __sz = __size;
330        __size = __other.__size;
331        __other.__size = __sz;
332    }
333
334    _LIBCPP_INLINE_VISIBILITY
335    size_type copy(_CharT* __s, size_type __n, size_type __pos = 0) const
336    {
337        if (__pos > size())
338            __throw_out_of_range("string_view::copy");
339        size_type __rlen = _VSTD::min(__n, size() - __pos);
340        _Traits::copy(__s, data() + __pos, __rlen);
341        return __rlen;
342    }
343
344    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
345    basic_string_view substr(size_type __pos = 0, size_type __n = npos) const
346    {
347        return __pos > size()
348            ? (__throw_out_of_range("string_view::substr"), basic_string_view())
349            : basic_string_view(data() + __pos, _VSTD::min(__n, size() - __pos));
350    }
351
352    _LIBCPP_CONSTEXPR_AFTER_CXX11 int compare(basic_string_view __sv) const _NOEXCEPT
353    {
354        size_type __rlen = _VSTD::min( size(), __sv.size());
355        int __retval = _Traits::compare(data(), __sv.data(), __rlen);
356        if ( __retval == 0 ) // first __rlen chars matched
357            __retval = size() == __sv.size() ? 0 : ( size() < __sv.size() ? -1 : 1 );
358        return __retval;
359    }
360
361    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
362    int compare(size_type __pos1, size_type __n1, basic_string_view __sv) const
363    {
364        return substr(__pos1, __n1).compare(__sv);
365    }
366
367    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
368    int compare(                       size_type __pos1, size_type __n1,
369                basic_string_view __sv, size_type __pos2, size_type __n2) const
370    {
371        return substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
372    }
373
374    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
375    int compare(const _CharT* __s) const _NOEXCEPT
376    {
377        return compare(basic_string_view(__s));
378    }
379
380    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
381    int compare(size_type __pos1, size_type __n1, const _CharT* __s) const
382    {
383        return substr(__pos1, __n1).compare(basic_string_view(__s));
384    }
385
386    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
387    int compare(size_type __pos1, size_type __n1, const _CharT* __s, size_type __n2) const
388    {
389        return substr(__pos1, __n1).compare(basic_string_view(__s, __n2));
390    }
391
392    // find
393    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
394    size_type find(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
395    {
396        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
397        return __str_find<value_type, size_type, traits_type, npos>
398            (data(), size(), __s.data(), __pos, __s.size());
399    }
400
401    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
402    size_type find(_CharT __c, size_type __pos = 0) const _NOEXCEPT
403    {
404        return __str_find<value_type, size_type, traits_type, npos>
405            (data(), size(), __c, __pos);
406    }
407
408    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
409    size_type find(const _CharT* __s, size_type __pos, size_type __n) const
410    {
411        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find(): received nullptr");
412        return __str_find<value_type, size_type, traits_type, npos>
413            (data(), size(), __s, __pos, __n);
414    }
415
416    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
417    size_type find(const _CharT* __s, size_type __pos = 0) const
418    {
419        _LIBCPP_ASSERT(__s != nullptr, "string_view::find(): received nullptr");
420        return __str_find<value_type, size_type, traits_type, npos>
421            (data(), size(), __s, __pos, traits_type::length(__s));
422    }
423
424    // rfind
425    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
426    size_type rfind(basic_string_view __s, size_type __pos = npos) const _NOEXCEPT
427    {
428        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find(): received nullptr");
429        return __str_rfind<value_type, size_type, traits_type, npos>
430            (data(), size(), __s.data(), __pos, __s.size());
431    }
432
433    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
434    size_type rfind(_CharT __c, size_type __pos = npos) const _NOEXCEPT
435    {
436        return __str_rfind<value_type, size_type, traits_type, npos>
437            (data(), size(), __c, __pos);
438    }
439
440    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
441    size_type rfind(const _CharT* __s, size_type __pos, size_type __n) const
442    {
443        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::rfind(): received nullptr");
444        return __str_rfind<value_type, size_type, traits_type, npos>
445            (data(), size(), __s, __pos, __n);
446    }
447
448    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
449    size_type rfind(const _CharT* __s, size_type __pos=npos) const
450    {
451        _LIBCPP_ASSERT(__s != nullptr, "string_view::rfind(): received nullptr");
452        return __str_rfind<value_type, size_type, traits_type, npos>
453            (data(), size(), __s, __pos, traits_type::length(__s));
454    }
455
456    // find_first_of
457    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
458    size_type find_first_of(basic_string_view __s, size_type __pos = 0) const _NOEXCEPT
459    {
460        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_of(): received nullptr");
461        return __str_find_first_of<value_type, size_type, traits_type, npos>
462            (data(), size(), __s.data(), __pos, __s.size());
463    }
464
465    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
466    size_type find_first_of(_CharT __c, size_type __pos = 0) const _NOEXCEPT
467    { return find(__c, __pos); }
468
469    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
470    size_type find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
471    {
472        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_first_of(): received nullptr");
473        return __str_find_first_of<value_type, size_type, traits_type, npos>
474            (data(), size(), __s, __pos, __n);
475    }
476
477    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
478    size_type find_first_of(const _CharT* __s, size_type __pos=0) const
479    {
480        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_of(): received nullptr");
481        return __str_find_first_of<value_type, size_type, traits_type, npos>
482            (data(), size(), __s, __pos, traits_type::length(__s));
483    }
484
485    // find_last_of
486    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
487    size_type find_last_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
488    {
489        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_of(): received nullptr");
490        return __str_find_last_of<value_type, size_type, traits_type, npos>
491            (data(), size(), __s.data(), __pos, __s.size());
492    }
493
494    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
495    size_type find_last_of(_CharT __c, size_type __pos = npos) const _NOEXCEPT
496    { return rfind(__c, __pos); }
497
498    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
499    size_type find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
500    {
501        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_last_of(): received nullptr");
502        return __str_find_last_of<value_type, size_type, traits_type, npos>
503            (data(), size(), __s, __pos, __n);
504    }
505
506    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
507    size_type find_last_of(const _CharT* __s, size_type __pos=npos) const
508    {
509        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_of(): received nullptr");
510        return __str_find_last_of<value_type, size_type, traits_type, npos>
511            (data(), size(), __s, __pos, traits_type::length(__s));
512    }
513
514    // find_first_not_of
515    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
516    size_type find_first_not_of(basic_string_view __s, size_type __pos=0) const _NOEXCEPT
517    {
518        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_first_not_of(): received nullptr");
519        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
520            (data(), size(), __s.data(), __pos, __s.size());
521    }
522
523    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
524    size_type find_first_not_of(_CharT __c, size_type __pos=0) const _NOEXCEPT
525    {
526        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
527            (data(), size(), __c, __pos);
528    }
529
530    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
531    size_type find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
532    {
533        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_first_not_of(): received nullptr");
534        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
535            (data(), size(), __s, __pos, __n);
536    }
537
538    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
539    size_type find_first_not_of(const _CharT* __s, size_type __pos=0) const
540    {
541        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_first_not_of(): received nullptr");
542        return __str_find_first_not_of<value_type, size_type, traits_type, npos>
543            (data(), size(), __s, __pos, traits_type::length(__s));
544    }
545
546    // find_last_not_of
547    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
548    size_type find_last_not_of(basic_string_view __s, size_type __pos=npos) const _NOEXCEPT
549    {
550        _LIBCPP_ASSERT(__s.size() == 0 || __s.data() != nullptr, "string_view::find_last_not_of(): received nullptr");
551        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
552            (data(), size(), __s.data(), __pos, __s.size());
553    }
554
555    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
556    size_type find_last_not_of(_CharT __c, size_type __pos=npos) const _NOEXCEPT
557    {
558        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
559            (data(), size(), __c, __pos);
560    }
561
562    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
563    size_type find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
564    {
565        _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string_view::find_last_not_of(): received nullptr");
566        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
567            (data(), size(), __s, __pos, __n);
568    }
569
570    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
571    size_type find_last_not_of(const _CharT* __s, size_type __pos=npos) const
572    {
573        _LIBCPP_ASSERT(__s != nullptr, "string_view::find_last_not_of(): received nullptr");
574        return __str_find_last_not_of<value_type, size_type, traits_type, npos>
575            (data(), size(), __s, __pos, traits_type::length(__s));
576    }
577
578#if _LIBCPP_STD_VER > 17
579    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
580    bool starts_with(basic_string_view __s) const _NOEXCEPT
581    { return size() >= __s.size() && compare(0, __s.size(), __s) == 0; }
582
583    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
584    bool starts_with(value_type __c) const _NOEXCEPT
585    { return !empty() && _Traits::eq(front(), __c); }
586
587    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
588    bool starts_with(const value_type* __s) const _NOEXCEPT
589    { return starts_with(basic_string_view(__s)); }
590
591    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
592    bool ends_with(basic_string_view __s) const _NOEXCEPT
593    { return size() >= __s.size() && compare(size() - __s.size(), npos, __s) == 0; }
594
595    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
596    bool ends_with(value_type __c) const _NOEXCEPT
597    { return !empty() && _Traits::eq(back(), __c); }
598
599    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
600    bool ends_with(const value_type* __s) const _NOEXCEPT
601    { return ends_with(basic_string_view(__s)); }
602#endif
603
604private:
605    const   value_type* __data;
606    size_type           __size;
607};
608
609
610// [string.view.comparison]
611// operator ==
612template<class _CharT, class _Traits>
613_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
614bool operator==(basic_string_view<_CharT, _Traits> __lhs,
615                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
616{
617    if ( __lhs.size() != __rhs.size()) return false;
618    return __lhs.compare(__rhs) == 0;
619}
620
621template<class _CharT, class _Traits>
622_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
623bool operator==(basic_string_view<_CharT, _Traits> __lhs,
624                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
625{
626    if ( __lhs.size() != __rhs.size()) return false;
627    return __lhs.compare(__rhs) == 0;
628}
629
630template<class _CharT, class _Traits>
631_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
632bool operator==(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
633                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
634{
635    if ( __lhs.size() != __rhs.size()) return false;
636    return __lhs.compare(__rhs) == 0;
637}
638
639
640// operator !=
641template<class _CharT, class _Traits>
642_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
643bool operator!=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
644{
645    if ( __lhs.size() != __rhs.size())
646        return true;
647    return __lhs.compare(__rhs) != 0;
648}
649
650template<class _CharT, class _Traits>
651_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
652bool operator!=(basic_string_view<_CharT, _Traits> __lhs,
653                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
654{
655    if ( __lhs.size() != __rhs.size())
656        return true;
657    return __lhs.compare(__rhs) != 0;
658}
659
660template<class _CharT, class _Traits>
661_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
662bool operator!=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
663                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
664{
665    if ( __lhs.size() != __rhs.size())
666        return true;
667    return __lhs.compare(__rhs) != 0;
668}
669
670
671// operator <
672template<class _CharT, class _Traits>
673_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
674bool operator<(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
675{
676    return __lhs.compare(__rhs) < 0;
677}
678
679template<class _CharT, class _Traits>
680_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
681bool operator<(basic_string_view<_CharT, _Traits> __lhs,
682                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
683{
684    return __lhs.compare(__rhs) < 0;
685}
686
687template<class _CharT, class _Traits>
688_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
689bool operator<(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
690                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
691{
692    return __lhs.compare(__rhs) < 0;
693}
694
695
696// operator >
697template<class _CharT, class _Traits>
698_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
699bool operator> (basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
700{
701    return __lhs.compare(__rhs) > 0;
702}
703
704template<class _CharT, class _Traits>
705_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
706bool operator>(basic_string_view<_CharT, _Traits> __lhs,
707                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
708{
709    return __lhs.compare(__rhs) > 0;
710}
711
712template<class _CharT, class _Traits>
713_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
714bool operator>(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
715                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
716{
717    return __lhs.compare(__rhs) > 0;
718}
719
720
721// operator <=
722template<class _CharT, class _Traits>
723_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
724bool operator<=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
725{
726    return __lhs.compare(__rhs) <= 0;
727}
728
729template<class _CharT, class _Traits>
730_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
731bool operator<=(basic_string_view<_CharT, _Traits> __lhs,
732                typename common_type<basic_string_view<_CharT, _Traits> >::type __rhs) _NOEXCEPT
733{
734    return __lhs.compare(__rhs) <= 0;
735}
736
737template<class _CharT, class _Traits>
738_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
739bool operator<=(typename common_type<basic_string_view<_CharT, _Traits> >::type __lhs,
740                basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
741{
742    return __lhs.compare(__rhs) <= 0;
743}
744
745
746// operator >=
747template<class _CharT, class _Traits>
748_LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
749bool operator>=(basic_string_view<_CharT, _Traits> __lhs, basic_string_view<_CharT, _Traits> __rhs) _NOEXCEPT
750{
751    return __lhs.compare(__rhs) >= 0;
752}
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
772template<class _CharT, class _Traits>
773basic_ostream<_CharT, _Traits>&
774operator<<(basic_ostream<_CharT, _Traits>& __os,
775           basic_string_view<_CharT, _Traits> __str);
776
777typedef basic_string_view<char>     string_view;
778#ifndef _LIBCPP_NO_HAS_CHAR8_T
779typedef basic_string_view<char8_t>  u8string_view;
780#endif
781typedef basic_string_view<char16_t> u16string_view;
782typedef basic_string_view<char32_t> u32string_view;
783typedef basic_string_view<wchar_t>  wstring_view;
784
785// [string.view.hash]
786template<class _CharT>
787struct _LIBCPP_TEMPLATE_VIS hash<basic_string_view<_CharT, char_traits<_CharT> > >
788    : public unary_function<basic_string_view<_CharT, char_traits<_CharT> >, size_t>
789{
790    _LIBCPP_INLINE_VISIBILITY
791    size_t operator()(const basic_string_view<_CharT, char_traits<_CharT> > __val) const _NOEXCEPT {
792        return __do_string_hash(__val.data(), __val.data() + __val.size());
793    }
794};
795
796
797#if _LIBCPP_STD_VER > 11
798inline namespace literals
799{
800  inline namespace string_view_literals
801  {
802    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
803    basic_string_view<char> operator "" sv(const char *__str, size_t __len) _NOEXCEPT
804    {
805        return basic_string_view<char> (__str, __len);
806    }
807
808    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
809    basic_string_view<wchar_t> operator "" sv(const wchar_t *__str, size_t __len) _NOEXCEPT
810    {
811        return basic_string_view<wchar_t> (__str, __len);
812    }
813
814#ifndef _LIBCPP_NO_HAS_CHAR8_T
815    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
816    basic_string_view<char8_t> operator "" sv(const char8_t *__str, size_t __len) _NOEXCEPT
817    {
818        return basic_string_view<char8_t> (__str, __len);
819    }
820#endif
821
822    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
823    basic_string_view<char16_t> operator "" sv(const char16_t *__str, size_t __len) _NOEXCEPT
824    {
825        return basic_string_view<char16_t> (__str, __len);
826    }
827
828    inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
829    basic_string_view<char32_t> operator "" sv(const char32_t *__str, size_t __len) _NOEXCEPT
830    {
831        return basic_string_view<char32_t> (__str, __len);
832    }
833  }
834}
835#endif
836_LIBCPP_END_NAMESPACE_STD
837
838_LIBCPP_POP_MACROS
839
840#endif // _LIBCPP_STRING_VIEW
841