xref: /freebsd-12.1/contrib/libc++/include/string (revision cc65eb4e)
1// -*- C++ -*-
2//===--------------------------- string -----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is distributed under the University of Illinois Open Source
7// License. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_STRING
12#define _LIBCPP_STRING
13
14/*
15    string synopsis
16
17namespace std
18{
19
20template <class stateT>
21class fpos
22{
23private:
24    stateT st;
25public:
26    fpos(streamoff = streamoff());
27
28    operator streamoff() const;
29
30    stateT state() const;
31    void state(stateT);
32
33    fpos& operator+=(streamoff);
34    fpos  operator+ (streamoff) const;
35    fpos& operator-=(streamoff);
36    fpos  operator- (streamoff) const;
37};
38
39template <class stateT> streamoff operator-(const fpos<stateT>& x, const fpos<stateT>& y);
40
41template <class stateT> bool operator==(const fpos<stateT>& x, const fpos<stateT>& y);
42template <class stateT> bool operator!=(const fpos<stateT>& x, const fpos<stateT>& y);
43
44template <class charT>
45struct char_traits
46{
47    typedef charT     char_type;
48    typedef ...       int_type;
49    typedef streamoff off_type;
50    typedef streampos pos_type;
51    typedef mbstate_t state_type;
52
53    static void assign(char_type& c1, const char_type& c2) noexcept;
54    static constexpr bool eq(char_type c1, char_type c2) noexcept;
55    static constexpr bool lt(char_type c1, char_type c2) noexcept;
56
57    static int              compare(const char_type* s1, const char_type* s2, size_t n);
58    static size_t           length(const char_type* s);
59    static const char_type* find(const char_type* s, size_t n, const char_type& a);
60    static char_type*       move(char_type* s1, const char_type* s2, size_t n);
61    static char_type*       copy(char_type* s1, const char_type* s2, size_t n);
62    static char_type*       assign(char_type* s, size_t n, char_type a);
63
64    static constexpr int_type  not_eof(int_type c) noexcept;
65    static constexpr char_type to_char_type(int_type c) noexcept;
66    static constexpr int_type  to_int_type(char_type c) noexcept;
67    static constexpr bool      eq_int_type(int_type c1, int_type c2) noexcept;
68    static constexpr int_type  eof() noexcept;
69};
70
71template <> struct char_traits<char>;
72template <> struct char_traits<wchar_t>;
73
74template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
75class basic_string
76{
77public:
78// types:
79    typedef traits traits_type;
80    typedef typename traits_type::char_type value_type;
81    typedef Allocator allocator_type;
82    typedef typename allocator_type::size_type size_type;
83    typedef typename allocator_type::difference_type difference_type;
84    typedef typename allocator_type::reference reference;
85    typedef typename allocator_type::const_reference const_reference;
86    typedef typename allocator_type::pointer pointer;
87    typedef typename allocator_type::const_pointer const_pointer;
88    typedef implementation-defined iterator;
89    typedef implementation-defined const_iterator;
90    typedef std::reverse_iterator<iterator> reverse_iterator;
91    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
92
93    static const size_type npos = -1;
94
95    basic_string()
96        noexcept(is_nothrow_default_constructible<allocator_type>::value);
97    explicit basic_string(const allocator_type& a);
98    basic_string(const basic_string& str);
99    basic_string(basic_string&& str)
100        noexcept(is_nothrow_move_constructible<allocator_type>::value);
101    basic_string(const basic_string& str, size_type pos,
102                 const allocator_type& a = allocator_type());
103    basic_string(const basic_string& str, size_type pos, size_type n,
104                 const Allocator& a = Allocator());
105    template<class T>
106        basic_string(const T& t, size_type pos, size_type n, const Allocator& a = Allocator()); // C++17
107    explicit basic_string(const basic_string_view<charT, traits> sv, const Allocator& a = Allocator());
108    basic_string(const value_type* s, const allocator_type& a = allocator_type());
109    basic_string(const value_type* s, size_type n, const allocator_type& a = allocator_type());
110    basic_string(size_type n, value_type c, const allocator_type& a = allocator_type());
111    template<class InputIterator>
112        basic_string(InputIterator begin, InputIterator end,
113                     const allocator_type& a = allocator_type());
114    basic_string(initializer_list<value_type>, const Allocator& = Allocator());
115    basic_string(const basic_string&, const Allocator&);
116    basic_string(basic_string&&, const Allocator&);
117
118    ~basic_string();
119
120    operator basic_string_view<charT, traits>() const noexcept;
121
122    basic_string& operator=(const basic_string& str);
123    basic_string& operator=(basic_string_view<charT, traits> sv);
124    basic_string& operator=(basic_string&& str)
125        noexcept(
126             allocator_type::propagate_on_container_move_assignment::value ||
127             allocator_type::is_always_equal::value ); // C++17
128    basic_string& operator=(const value_type* s);
129    basic_string& operator=(value_type c);
130    basic_string& operator=(initializer_list<value_type>);
131
132    iterator       begin() noexcept;
133    const_iterator begin() const noexcept;
134    iterator       end() noexcept;
135    const_iterator end() const noexcept;
136
137    reverse_iterator       rbegin() noexcept;
138    const_reverse_iterator rbegin() const noexcept;
139    reverse_iterator       rend() noexcept;
140    const_reverse_iterator rend() const noexcept;
141
142    const_iterator         cbegin() const noexcept;
143    const_iterator         cend() const noexcept;
144    const_reverse_iterator crbegin() const noexcept;
145    const_reverse_iterator crend() const noexcept;
146
147    size_type size() const noexcept;
148    size_type length() const noexcept;
149    size_type max_size() const noexcept;
150    size_type capacity() const noexcept;
151
152    void resize(size_type n, value_type c);
153    void resize(size_type n);
154
155    void reserve(size_type res_arg = 0);
156    void shrink_to_fit();
157    void clear() noexcept;
158    bool empty() const noexcept;
159
160    const_reference operator[](size_type pos) const;
161    reference       operator[](size_type pos);
162
163    const_reference at(size_type n) const;
164    reference       at(size_type n);
165
166    basic_string& operator+=(const basic_string& str);
167    basic_string& operator+=(basic_string_view<charT, traits> sv);
168    basic_string& operator+=(const value_type* s);
169    basic_string& operator+=(value_type c);
170    basic_string& operator+=(initializer_list<value_type>);
171
172    basic_string& append(const basic_string& str);
173    basic_string& append(basic_string_view<charT, traits> sv);
174    basic_string& append(const basic_string& str, size_type pos, size_type n=npos); //C++14
175    template <class T>
176        basic_string& append(const T& t, size_type pos, size_type n=npos); // C++17
177    basic_string& append(const value_type* s, size_type n);
178    basic_string& append(const value_type* s);
179    basic_string& append(size_type n, value_type c);
180    template<class InputIterator>
181        basic_string& append(InputIterator first, InputIterator last);
182    basic_string& append(initializer_list<value_type>);
183
184    void push_back(value_type c);
185    void pop_back();
186    reference       front();
187    const_reference front() const;
188    reference       back();
189    const_reference back() const;
190
191    basic_string& assign(const basic_string& str);
192    basic_string& assign(basic_string_view<charT, traits> sv);
193    basic_string& assign(basic_string&& str);
194    basic_string& assign(const basic_string& str, size_type pos, size_type n=npos); // C++14
195    template <class T>
196        basic_string& assign(const T& t, size_type pos, size_type n=npos); // C++17
197    basic_string& assign(const value_type* s, size_type n);
198    basic_string& assign(const value_type* s);
199    basic_string& assign(size_type n, value_type c);
200    template<class InputIterator>
201        basic_string& assign(InputIterator first, InputIterator last);
202    basic_string& assign(initializer_list<value_type>);
203
204    basic_string& insert(size_type pos1, const basic_string& str);
205    basic_string& insert(size_type pos1, basic_string_view<charT, traits> sv);
206    basic_string& insert(size_type pos1, const basic_string& str,
207                         size_type pos2, size_type n);
208    template <class T>
209        basic_string& insert(size_type pos1, const T& t, size_type pos2, size_type n); // C++17
210    basic_string& insert(size_type pos, const value_type* s, size_type n=npos); //C++14
211    basic_string& insert(size_type pos, const value_type* s);
212    basic_string& insert(size_type pos, size_type n, value_type c);
213    iterator      insert(const_iterator p, value_type c);
214    iterator      insert(const_iterator p, size_type n, value_type c);
215    template<class InputIterator>
216        iterator insert(const_iterator p, InputIterator first, InputIterator last);
217    iterator      insert(const_iterator p, initializer_list<value_type>);
218
219    basic_string& erase(size_type pos = 0, size_type n = npos);
220    iterator      erase(const_iterator position);
221    iterator      erase(const_iterator first, const_iterator last);
222
223    basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
224    basic_string& replace(size_type pos1, size_type n1, basic_string_view<charT, traits> sv);
225    basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
226                          size_type pos2, size_type n2=npos); // C++14
227    template <class T>
228        basic_string& replace(size_type pos1, size_type n1, const T& t,
229                              size_type pos2, size_type n); // C++17
230    basic_string& replace(size_type pos, size_type n1, const value_type* s, size_type n2);
231    basic_string& replace(size_type pos, size_type n1, const value_type* s);
232    basic_string& replace(size_type pos, size_type n1, size_type n2, value_type c);
233    basic_string& replace(const_iterator i1, const_iterator i2, const basic_string& str);
234    basic_string& replace(const_iterator i1, const_iterator i2, basic_string_view<charT, traits> sv);
235    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s, size_type n);
236    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s);
237    basic_string& replace(const_iterator i1, const_iterator i2, size_type n, value_type c);
238    template<class InputIterator>
239        basic_string& replace(const_iterator i1, const_iterator i2, InputIterator j1, InputIterator j2);
240    basic_string& replace(const_iterator i1, const_iterator i2, initializer_list<value_type>);
241
242    size_type copy(value_type* s, size_type n, size_type pos = 0) const;
243    basic_string substr(size_type pos = 0, size_type n = npos) const;
244
245    void swap(basic_string& str)
246        noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
247                 allocator_traits<allocator_type>::is_always_equal::value);  // C++17
248
249    const value_type* c_str() const noexcept;
250    const value_type* data() const noexcept;
251          value_type* data()       noexcept;   // C++17
252
253    allocator_type get_allocator() const noexcept;
254
255    size_type find(const basic_string& str, size_type pos = 0) const noexcept;
256    size_type find(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
257    size_type find(const value_type* s, size_type pos, size_type n) const noexcept;
258    size_type find(const value_type* s, size_type pos = 0) const noexcept;
259    size_type find(value_type c, size_type pos = 0) const noexcept;
260
261    size_type rfind(const basic_string& str, size_type pos = npos) const noexcept;
262    size_type ffind(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
263    size_type rfind(const value_type* s, size_type pos, size_type n) const noexcept;
264    size_type rfind(const value_type* s, size_type pos = npos) const noexcept;
265    size_type rfind(value_type c, size_type pos = npos) const noexcept;
266
267    size_type find_first_of(const basic_string& str, size_type pos = 0) const noexcept;
268    size_type find_first_of(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
269    size_type find_first_of(const value_type* s, size_type pos, size_type n) const noexcept;
270    size_type find_first_of(const value_type* s, size_type pos = 0) const noexcept;
271    size_type find_first_of(value_type c, size_type pos = 0) const noexcept;
272
273    size_type find_last_of(const basic_string& str, size_type pos = npos) const noexcept;
274    size_type find_last_of(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
275    size_type find_last_of(const value_type* s, size_type pos, size_type n) const noexcept;
276    size_type find_last_of(const value_type* s, size_type pos = npos) const noexcept;
277    size_type find_last_of(value_type c, size_type pos = npos) const noexcept;
278
279    size_type find_first_not_of(const basic_string& str, size_type pos = 0) const noexcept;
280    size_type find_first_not_of(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
281    size_type find_first_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
282    size_type find_first_not_of(const value_type* s, size_type pos = 0) const noexcept;
283    size_type find_first_not_of(value_type c, size_type pos = 0) const noexcept;
284
285    size_type find_last_not_of(const basic_string& str, size_type pos = npos) const noexcept;
286    size_type find_last_not_of(basic_string_view<charT, traits> sv, size_type pos = 0) const noexcept;
287    size_type find_last_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
288    size_type find_last_not_of(const value_type* s, size_type pos = npos) const noexcept;
289    size_type find_last_not_of(value_type c, size_type pos = npos) const noexcept;
290
291    int compare(const basic_string& str) const noexcept;
292    int compare(basic_string_view<charT, traits> sv) const noexcept;
293    int compare(size_type pos1, size_type n1, const basic_string& str) const;
294    int compare(size_type pos1, size_type n1, basic_string_view<charT, traits> sv) const;
295    int compare(size_type pos1, size_type n1, const basic_string& str,
296                size_type pos2, size_type n2=npos) const; // C++14
297    template <class T>
298        int compare(size_type pos1, size_type n1, const T& t,
299                    size_type pos2, size_type n2=npos) const; // C++17
300    int compare(const value_type* s) const noexcept;
301    int compare(size_type pos1, size_type n1, const value_type* s) const;
302    int compare(size_type pos1, size_type n1, const value_type* s, size_type n2) const;
303
304    bool __invariants() const;
305};
306
307template<class charT, class traits, class Allocator>
308basic_string<charT, traits, Allocator>
309operator+(const basic_string<charT, traits, Allocator>& lhs,
310          const basic_string<charT, traits, Allocator>& rhs);
311
312template<class charT, class traits, class Allocator>
313basic_string<charT, traits, Allocator>
314operator+(const charT* lhs , const basic_string<charT,traits,Allocator>&rhs);
315
316template<class charT, class traits, class Allocator>
317basic_string<charT, traits, Allocator>
318operator+(charT lhs, const basic_string<charT,traits,Allocator>& rhs);
319
320template<class charT, class traits, class Allocator>
321basic_string<charT, traits, Allocator>
322operator+(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs);
323
324template<class charT, class traits, class Allocator>
325basic_string<charT, traits, Allocator>
326operator+(const basic_string<charT, traits, Allocator>& lhs, charT rhs);
327
328template<class charT, class traits, class Allocator>
329bool operator==(const basic_string<charT, traits, Allocator>& lhs,
330                const basic_string<charT, traits, Allocator>& rhs) noexcept;
331
332template<class charT, class traits, class Allocator>
333bool operator==(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
334
335template<class charT, class traits, class Allocator>
336bool operator==(const basic_string<charT,traits,Allocator>& lhs, const charT* rhs) noexcept;
337
338template<class charT, class traits, class Allocator>
339bool operator!=(const basic_string<charT,traits,Allocator>& lhs,
340                const basic_string<charT, traits, Allocator>& rhs) noexcept;
341
342template<class charT, class traits, class Allocator>
343bool operator!=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
344
345template<class charT, class traits, class Allocator>
346bool operator!=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
347
348template<class charT, class traits, class Allocator>
349bool operator< (const basic_string<charT, traits, Allocator>& lhs,
350                const basic_string<charT, traits, Allocator>& rhs) noexcept;
351
352template<class charT, class traits, class Allocator>
353bool operator< (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
354
355template<class charT, class traits, class Allocator>
356bool operator< (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
357
358template<class charT, class traits, class Allocator>
359bool operator> (const basic_string<charT, traits, Allocator>& lhs,
360                const basic_string<charT, traits, Allocator>& rhs) noexcept;
361
362template<class charT, class traits, class Allocator>
363bool operator> (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
364
365template<class charT, class traits, class Allocator>
366bool operator> (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
367
368template<class charT, class traits, class Allocator>
369bool operator<=(const basic_string<charT, traits, Allocator>& lhs,
370                const basic_string<charT, traits, Allocator>& rhs) noexcept;
371
372template<class charT, class traits, class Allocator>
373bool operator<=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
374
375template<class charT, class traits, class Allocator>
376bool operator<=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
377
378template<class charT, class traits, class Allocator>
379bool operator>=(const basic_string<charT, traits, Allocator>& lhs,
380                const basic_string<charT, traits, Allocator>& rhs) noexcept;
381
382template<class charT, class traits, class Allocator>
383bool operator>=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
384
385template<class charT, class traits, class Allocator>
386bool operator>=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
387
388template<class charT, class traits, class Allocator>
389void swap(basic_string<charT, traits, Allocator>& lhs,
390          basic_string<charT, traits, Allocator>& rhs)
391            noexcept(noexcept(lhs.swap(rhs)));
392
393template<class charT, class traits, class Allocator>
394basic_istream<charT, traits>&
395operator>>(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
396
397template<class charT, class traits, class Allocator>
398basic_ostream<charT, traits>&
399operator<<(basic_ostream<charT, traits>& os, const basic_string<charT, traits, Allocator>& str);
400
401template<class charT, class traits, class Allocator>
402basic_istream<charT, traits>&
403getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str,
404        charT delim);
405
406template<class charT, class traits, class Allocator>
407basic_istream<charT, traits>&
408getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
409
410typedef basic_string<char>    string;
411typedef basic_string<wchar_t> wstring;
412typedef basic_string<char16_t> u16string;
413typedef basic_string<char32_t> u32string;
414
415int                stoi  (const string& str, size_t* idx = 0, int base = 10);
416long               stol  (const string& str, size_t* idx = 0, int base = 10);
417unsigned long      stoul (const string& str, size_t* idx = 0, int base = 10);
418long long          stoll (const string& str, size_t* idx = 0, int base = 10);
419unsigned long long stoull(const string& str, size_t* idx = 0, int base = 10);
420
421float       stof (const string& str, size_t* idx = 0);
422double      stod (const string& str, size_t* idx = 0);
423long double stold(const string& str, size_t* idx = 0);
424
425string to_string(int val);
426string to_string(unsigned val);
427string to_string(long val);
428string to_string(unsigned long val);
429string to_string(long long val);
430string to_string(unsigned long long val);
431string to_string(float val);
432string to_string(double val);
433string to_string(long double val);
434
435int                stoi  (const wstring& str, size_t* idx = 0, int base = 10);
436long               stol  (const wstring& str, size_t* idx = 0, int base = 10);
437unsigned long      stoul (const wstring& str, size_t* idx = 0, int base = 10);
438long long          stoll (const wstring& str, size_t* idx = 0, int base = 10);
439unsigned long long stoull(const wstring& str, size_t* idx = 0, int base = 10);
440
441float       stof (const wstring& str, size_t* idx = 0);
442double      stod (const wstring& str, size_t* idx = 0);
443long double stold(const wstring& str, size_t* idx = 0);
444
445wstring to_wstring(int val);
446wstring to_wstring(unsigned val);
447wstring to_wstring(long val);
448wstring to_wstring(unsigned long val);
449wstring to_wstring(long long val);
450wstring to_wstring(unsigned long long val);
451wstring to_wstring(float val);
452wstring to_wstring(double val);
453wstring to_wstring(long double val);
454
455template <> struct hash<string>;
456template <> struct hash<u16string>;
457template <> struct hash<u32string>;
458template <> struct hash<wstring>;
459
460basic_string<char>     operator "" s( const char *str,     size_t len ); // C++14
461basic_string<wchar_t>  operator "" s( const wchar_t *str,  size_t len ); // C++14
462basic_string<char16_t> operator "" s( const char16_t *str, size_t len ); // C++14
463basic_string<char32_t> operator "" s( const char32_t *str, size_t len ); // C++14
464
465}  // std
466
467*/
468
469#include <__config>
470#include <string_view>
471#include <iosfwd>
472#include <cstring>
473#include <cstdio>  // For EOF.
474#include <cwchar>
475#include <algorithm>
476#include <iterator>
477#include <utility>
478#include <memory>
479#include <stdexcept>
480#include <type_traits>
481#include <initializer_list>
482#include <__functional_base>
483#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
484#include <cstdint>
485#endif
486
487#include <__undef_min_max>
488
489#include <__debug>
490
491#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
492#pragma GCC system_header
493#endif
494
495_LIBCPP_BEGIN_NAMESPACE_STD
496
497// fpos
498
499template <class _StateT>
500class _LIBCPP_TEMPLATE_VIS fpos
501{
502private:
503    _StateT __st_;
504    streamoff __off_;
505public:
506    _LIBCPP_INLINE_VISIBILITY fpos(streamoff __off = streamoff()) : __st_(), __off_(__off) {}
507
508    _LIBCPP_INLINE_VISIBILITY operator streamoff() const {return __off_;}
509
510    _LIBCPP_INLINE_VISIBILITY _StateT state() const {return __st_;}
511    _LIBCPP_INLINE_VISIBILITY void state(_StateT __st) {__st_ = __st;}
512
513    _LIBCPP_INLINE_VISIBILITY fpos& operator+=(streamoff __off) {__off_ += __off; return *this;}
514    _LIBCPP_INLINE_VISIBILITY fpos  operator+ (streamoff __off) const {fpos __t(*this); __t += __off; return __t;}
515    _LIBCPP_INLINE_VISIBILITY fpos& operator-=(streamoff __off) {__off_ -= __off; return *this;}
516    _LIBCPP_INLINE_VISIBILITY fpos  operator- (streamoff __off) const {fpos __t(*this); __t -= __off; return __t;}
517};
518
519template <class _StateT>
520inline _LIBCPP_INLINE_VISIBILITY
521streamoff operator-(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
522    {return streamoff(__x) - streamoff(__y);}
523
524template <class _StateT>
525inline _LIBCPP_INLINE_VISIBILITY
526bool operator==(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
527    {return streamoff(__x) == streamoff(__y);}
528
529template <class _StateT>
530inline _LIBCPP_INLINE_VISIBILITY
531bool operator!=(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
532    {return streamoff(__x) != streamoff(__y);}
533
534// basic_string
535
536template<class _CharT, class _Traits, class _Allocator>
537basic_string<_CharT, _Traits, _Allocator>
538operator+(const basic_string<_CharT, _Traits, _Allocator>& __x,
539          const basic_string<_CharT, _Traits, _Allocator>& __y);
540
541template<class _CharT, class _Traits, class _Allocator>
542basic_string<_CharT, _Traits, _Allocator>
543operator+(const _CharT* __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
544
545template<class _CharT, class _Traits, class _Allocator>
546basic_string<_CharT, _Traits, _Allocator>
547operator+(_CharT __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
548
549template<class _CharT, class _Traits, class _Allocator>
550basic_string<_CharT, _Traits, _Allocator>
551operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, const _CharT* __y);
552
553template<class _CharT, class _Traits, class _Allocator>
554basic_string<_CharT, _Traits, _Allocator>
555operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, _CharT __y);
556
557template <bool>
558class _LIBCPP_TEMPLATE_VIS __basic_string_common
559{
560protected:
561    _LIBCPP_NORETURN void __throw_length_error() const;
562    _LIBCPP_NORETURN void __throw_out_of_range() const;
563};
564
565template <bool __b>
566void
567__basic_string_common<__b>::__throw_length_error() const
568{
569    _VSTD::__throw_length_error("basic_string");
570}
571
572template <bool __b>
573void
574__basic_string_common<__b>::__throw_out_of_range() const
575{
576    _VSTD::__throw_out_of_range("basic_string");
577}
578
579#ifdef _LIBCPP_MSVC
580#pragma warning( push )
581#pragma warning( disable: 4231 )
582#endif // _LIBCPP_MSVC
583_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __basic_string_common<true>)
584#ifdef _LIBCPP_MSVC
585#pragma warning( pop )
586#endif // _LIBCPP_MSVC
587
588#ifdef _LIBCPP_NO_EXCEPTIONS
589template <class _Iter>
590struct __libcpp_string_gets_noexcept_iterator_impl : public true_type {};
591#elif defined(_LIBCPP_HAS_NO_NOEXCEPT)
592template <class _Iter>
593struct __libcpp_string_gets_noexcept_iterator_impl : public false_type {};
594#else
595template <class _Iter, bool = __is_forward_iterator<_Iter>::value>
596struct __libcpp_string_gets_noexcept_iterator_impl : public _LIBCPP_BOOL_CONSTANT((
597    noexcept(++(declval<_Iter&>())) &&
598    is_nothrow_assignable<_Iter&, _Iter>::value &&
599    noexcept(declval<_Iter>() == declval<_Iter>()) &&
600    noexcept(*declval<_Iter>())
601)) {};
602
603template <class _Iter>
604struct __libcpp_string_gets_noexcept_iterator_impl<_Iter, false> : public false_type {};
605#endif
606
607
608template <class _Iter>
609struct __libcpp_string_gets_noexcept_iterator
610    : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value || __libcpp_string_gets_noexcept_iterator_impl<_Iter>::value) {};
611
612template <class _CharT, class _Traits, class _Tp>
613struct __can_be_converted_to_string_view : public _LIBCPP_BOOL_CONSTANT(
614	( is_convertible<const _Tp&, basic_string_view<_CharT, _Traits> >::value &&
615     !is_convertible<const _Tp&, const _CharT*>::value)) {};
616
617#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
618
619template <class _CharT, size_t = sizeof(_CharT)>
620struct __padding
621{
622    unsigned char __xx[sizeof(_CharT)-1];
623};
624
625template <class _CharT>
626struct __padding<_CharT, 1>
627{
628};
629
630#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
631
632template<class _CharT, class _Traits, class _Allocator>
633class _LIBCPP_TEMPLATE_VIS basic_string
634    : private __basic_string_common<true>
635{
636public:
637    typedef basic_string                                 __self;
638    typedef basic_string_view<_CharT, _Traits>           __self_view;
639    typedef _Traits                                      traits_type;
640    typedef typename traits_type::char_type              value_type;
641    typedef _Allocator                                   allocator_type;
642    typedef allocator_traits<allocator_type>             __alloc_traits;
643    typedef typename __alloc_traits::size_type           size_type;
644    typedef typename __alloc_traits::difference_type     difference_type;
645    typedef value_type&                                  reference;
646    typedef const value_type&                            const_reference;
647    typedef typename __alloc_traits::pointer             pointer;
648    typedef typename __alloc_traits::const_pointer       const_pointer;
649
650    static_assert(is_pod<value_type>::value, "Character type of basic_string must be a POD");
651    static_assert((is_same<_CharT, value_type>::value),
652                  "traits_type::char_type must be the same type as CharT");
653    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
654                  "Allocator::value_type must be same type as value_type");
655#if defined(_LIBCPP_RAW_ITERATORS)
656    typedef pointer                                      iterator;
657    typedef const_pointer                                const_iterator;
658#else  // defined(_LIBCPP_RAW_ITERATORS)
659    typedef __wrap_iter<pointer>                         iterator;
660    typedef __wrap_iter<const_pointer>                   const_iterator;
661#endif  // defined(_LIBCPP_RAW_ITERATORS)
662    typedef _VSTD::reverse_iterator<iterator>             reverse_iterator;
663    typedef _VSTD::reverse_iterator<const_iterator>       const_reverse_iterator;
664
665private:
666
667#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
668
669    struct __long
670    {
671        pointer   __data_;
672        size_type __size_;
673        size_type __cap_;
674    };
675
676#if _LIBCPP_BIG_ENDIAN
677    enum {__short_mask = 0x01};
678    enum {__long_mask  = 0x1ul};
679#else  // _LIBCPP_BIG_ENDIAN
680    enum {__short_mask = 0x80};
681    enum {__long_mask  = ~(size_type(~0) >> 1)};
682#endif  // _LIBCPP_BIG_ENDIAN
683
684    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
685                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
686
687    struct __short
688    {
689        value_type __data_[__min_cap];
690        struct
691            : __padding<value_type>
692        {
693            unsigned char __size_;
694        };
695    };
696
697#else
698
699    struct __long
700    {
701        size_type __cap_;
702        size_type __size_;
703        pointer   __data_;
704    };
705
706#if _LIBCPP_BIG_ENDIAN
707    enum {__short_mask = 0x80};
708    enum {__long_mask  = ~(size_type(~0) >> 1)};
709#else  // _LIBCPP_BIG_ENDIAN
710    enum {__short_mask = 0x01};
711    enum {__long_mask  = 0x1ul};
712#endif  // _LIBCPP_BIG_ENDIAN
713
714    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
715                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
716
717    struct __short
718    {
719        union
720        {
721            unsigned char __size_;
722            value_type __lx;
723        };
724        value_type __data_[__min_cap];
725    };
726
727#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
728
729    union __ulx{__long __lx; __short __lxx;};
730
731    enum {__n_words = sizeof(__ulx) / sizeof(size_type)};
732
733    struct __raw
734    {
735        size_type __words[__n_words];
736    };
737
738    struct __rep
739    {
740        union
741        {
742            __long  __l;
743            __short __s;
744            __raw   __r;
745        };
746    };
747
748    __compressed_pair<__rep, allocator_type> __r_;
749
750public:
751    static const size_type npos = -1;
752
753    _LIBCPP_INLINE_VISIBILITY basic_string()
754        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
755
756    _LIBCPP_INLINE_VISIBILITY explicit basic_string(const allocator_type& __a)
757#if _LIBCPP_STD_VER <= 14
758        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value);
759#else
760        _NOEXCEPT;
761#endif
762
763    basic_string(const basic_string& __str);
764    basic_string(const basic_string& __str, const allocator_type& __a);
765
766#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
767    _LIBCPP_INLINE_VISIBILITY
768    basic_string(basic_string&& __str)
769#if _LIBCPP_STD_VER <= 14
770        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
771#else
772        _NOEXCEPT;
773#endif
774
775    _LIBCPP_INLINE_VISIBILITY
776    basic_string(basic_string&& __str, const allocator_type& __a);
777#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
778    _LIBCPP_INLINE_VISIBILITY basic_string(const value_type* __s);
779    _LIBCPP_INLINE_VISIBILITY
780    basic_string(const value_type* __s, const allocator_type& __a);
781    _LIBCPP_INLINE_VISIBILITY
782    basic_string(const value_type* __s, size_type __n);
783    _LIBCPP_INLINE_VISIBILITY
784    basic_string(const value_type* __s, size_type __n, const allocator_type& __a);
785    _LIBCPP_INLINE_VISIBILITY
786    basic_string(size_type __n, value_type __c);
787    _LIBCPP_INLINE_VISIBILITY
788    basic_string(size_type __n, value_type __c, const allocator_type& __a);
789    basic_string(const basic_string& __str, size_type __pos, size_type __n,
790                 const allocator_type& __a = allocator_type());
791    _LIBCPP_INLINE_VISIBILITY
792    basic_string(const basic_string& __str, size_type __pos,
793                 const allocator_type& __a = allocator_type());
794    template<class _Tp>
795        basic_string(const _Tp& __t, size_type __pos, size_type __n,
796                     const allocator_type& __a = allocator_type(),
797                     typename enable_if<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, void>::type* = 0);
798    _LIBCPP_INLINE_VISIBILITY explicit
799    basic_string(__self_view __sv);
800    _LIBCPP_INLINE_VISIBILITY
801    basic_string(__self_view __sv, const allocator_type& __a);
802    template<class _InputIterator>
803        _LIBCPP_INLINE_VISIBILITY
804        basic_string(_InputIterator __first, _InputIterator __last);
805    template<class _InputIterator>
806        _LIBCPP_INLINE_VISIBILITY
807        basic_string(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
808#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
809    _LIBCPP_INLINE_VISIBILITY
810    basic_string(initializer_list<value_type> __il);
811    _LIBCPP_INLINE_VISIBILITY
812    basic_string(initializer_list<value_type> __il, const allocator_type& __a);
813#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
814
815    inline ~basic_string();
816
817    _LIBCPP_INLINE_VISIBILITY
818    operator __self_view() const _NOEXCEPT { return __self_view(data(), size()); }
819
820    basic_string& operator=(const basic_string& __str);
821
822#ifndef _LIBCPP_CXX03_LANG
823    template <class = void>
824#endif
825    _LIBCPP_INLINE_VISIBILITY
826    basic_string& operator=(__self_view __sv)  {return assign(__sv);}
827#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
828    _LIBCPP_INLINE_VISIBILITY
829    basic_string& operator=(basic_string&& __str)
830        _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value));
831#endif
832    _LIBCPP_INLINE_VISIBILITY basic_string& operator=(const value_type* __s) {return assign(__s);}
833    basic_string& operator=(value_type __c);
834#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
835    _LIBCPP_INLINE_VISIBILITY
836    basic_string& operator=(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
837#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
838
839#if _LIBCPP_DEBUG_LEVEL >= 2
840    _LIBCPP_INLINE_VISIBILITY
841    iterator begin() _NOEXCEPT
842        {return iterator(this, __get_pointer());}
843    _LIBCPP_INLINE_VISIBILITY
844    const_iterator begin() const _NOEXCEPT
845        {return const_iterator(this, __get_pointer());}
846    _LIBCPP_INLINE_VISIBILITY
847    iterator end() _NOEXCEPT
848        {return iterator(this, __get_pointer() + size());}
849    _LIBCPP_INLINE_VISIBILITY
850    const_iterator end() const _NOEXCEPT
851        {return const_iterator(this, __get_pointer() + size());}
852#else
853    _LIBCPP_INLINE_VISIBILITY
854    iterator begin() _NOEXCEPT
855        {return iterator(__get_pointer());}
856    _LIBCPP_INLINE_VISIBILITY
857    const_iterator begin() const _NOEXCEPT
858        {return const_iterator(__get_pointer());}
859    _LIBCPP_INLINE_VISIBILITY
860    iterator end() _NOEXCEPT
861        {return iterator(__get_pointer() + size());}
862    _LIBCPP_INLINE_VISIBILITY
863    const_iterator end() const _NOEXCEPT
864        {return const_iterator(__get_pointer() + size());}
865#endif  // _LIBCPP_DEBUG_LEVEL >= 2
866    _LIBCPP_INLINE_VISIBILITY
867    reverse_iterator rbegin() _NOEXCEPT
868        {return reverse_iterator(end());}
869    _LIBCPP_INLINE_VISIBILITY
870    const_reverse_iterator rbegin() const _NOEXCEPT
871        {return const_reverse_iterator(end());}
872    _LIBCPP_INLINE_VISIBILITY
873    reverse_iterator rend() _NOEXCEPT
874        {return reverse_iterator(begin());}
875    _LIBCPP_INLINE_VISIBILITY
876    const_reverse_iterator rend() const _NOEXCEPT
877        {return const_reverse_iterator(begin());}
878
879    _LIBCPP_INLINE_VISIBILITY
880    const_iterator cbegin() const _NOEXCEPT
881        {return begin();}
882    _LIBCPP_INLINE_VISIBILITY
883    const_iterator cend() const _NOEXCEPT
884        {return end();}
885    _LIBCPP_INLINE_VISIBILITY
886    const_reverse_iterator crbegin() const _NOEXCEPT
887        {return rbegin();}
888    _LIBCPP_INLINE_VISIBILITY
889    const_reverse_iterator crend() const _NOEXCEPT
890        {return rend();}
891
892    _LIBCPP_INLINE_VISIBILITY size_type size() const _NOEXCEPT
893        {return __is_long() ? __get_long_size() : __get_short_size();}
894    _LIBCPP_INLINE_VISIBILITY size_type length() const _NOEXCEPT {return size();}
895    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT;
896    _LIBCPP_INLINE_VISIBILITY size_type capacity() const _NOEXCEPT
897        {return (__is_long() ? __get_long_cap()
898                             : static_cast<size_type>(__min_cap)) - 1;}
899
900    void resize(size_type __n, value_type __c);
901    _LIBCPP_INLINE_VISIBILITY void resize(size_type __n) {resize(__n, value_type());}
902
903    void reserve(size_type res_arg = 0);
904    _LIBCPP_INLINE_VISIBILITY
905    void shrink_to_fit() _NOEXCEPT {reserve();}
906    _LIBCPP_INLINE_VISIBILITY
907    void clear() _NOEXCEPT;
908    _LIBCPP_INLINE_VISIBILITY bool empty() const _NOEXCEPT {return size() == 0;}
909
910    _LIBCPP_INLINE_VISIBILITY const_reference operator[](size_type __pos) const _NOEXCEPT;
911    _LIBCPP_INLINE_VISIBILITY reference       operator[](size_type __pos)       _NOEXCEPT;
912
913    const_reference at(size_type __n) const;
914    reference       at(size_type __n);
915
916    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const basic_string& __str) {return append(__str);}
917    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(__self_view __sv)          {return append(__sv);}
918    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const value_type* __s)     {return append(__s);}
919    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(value_type __c)            {push_back(__c); return *this;}
920#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
921    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(initializer_list<value_type> __il) {return append(__il);}
922#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
923
924    _LIBCPP_INLINE_VISIBILITY
925    basic_string& append(const basic_string& __str);
926    _LIBCPP_INLINE_VISIBILITY
927    basic_string& append(__self_view __sv) { return append(__sv.data(), __sv.size()); }
928    basic_string& append(const basic_string& __str, size_type __pos, size_type __n=npos);
929    template <class _Tp>
930        typename enable_if
931        <
932            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
933            basic_string&
934        >::type
935                  append(const _Tp& __t, size_type __pos, size_type __n=npos);
936    basic_string& append(const value_type* __s, size_type __n);
937    basic_string& append(const value_type* __s);
938    basic_string& append(size_type __n, value_type __c);
939    template <class _ForwardIterator>
940    inline basic_string& __append_forward_unsafe(_ForwardIterator, _ForwardIterator);
941    template<class _InputIterator>
942        typename enable_if
943        <
944            __is_exactly_input_iterator<_InputIterator>::value
945                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
946            basic_string&
947        >::type
948    _LIBCPP_INLINE_VISIBILITY
949    append(_InputIterator __first, _InputIterator __last) {
950      const basic_string __temp (__first, __last, __alloc());
951      append(__temp.data(), __temp.size());
952      return *this;
953    }
954    template<class _ForwardIterator>
955        typename enable_if
956        <
957            __is_forward_iterator<_ForwardIterator>::value
958                && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
959            basic_string&
960        >::type
961    _LIBCPP_INLINE_VISIBILITY
962    append(_ForwardIterator __first, _ForwardIterator __last) {
963      return __append_forward_unsafe(__first, __last);
964    }
965
966#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
967    _LIBCPP_INLINE_VISIBILITY
968    basic_string& append(initializer_list<value_type> __il) {return append(__il.begin(), __il.size());}
969#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
970
971    void push_back(value_type __c);
972    _LIBCPP_INLINE_VISIBILITY
973    void pop_back();
974    _LIBCPP_INLINE_VISIBILITY reference       front();
975    _LIBCPP_INLINE_VISIBILITY const_reference front() const;
976    _LIBCPP_INLINE_VISIBILITY reference       back();
977    _LIBCPP_INLINE_VISIBILITY const_reference back() const;
978
979    _LIBCPP_INLINE_VISIBILITY
980    basic_string& assign(__self_view __sv) { return assign(__sv.data(), __sv.size()); }
981    _LIBCPP_INLINE_VISIBILITY
982    basic_string& assign(const basic_string& __str) { return *this = __str; }
983#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
984    _LIBCPP_INLINE_VISIBILITY
985    basic_string& assign(basic_string&& str)
986        _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value))
987        {*this = _VSTD::move(str); return *this;}
988#endif
989    basic_string& assign(const basic_string& __str, size_type __pos, size_type __n=npos);
990    template <class _Tp>
991        typename enable_if
992        <
993            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
994            basic_string&
995        >::type
996                  assign(const _Tp & __t, size_type pos, size_type n=npos);
997    basic_string& assign(const value_type* __s, size_type __n);
998    basic_string& assign(const value_type* __s);
999    basic_string& assign(size_type __n, value_type __c);
1000    template<class _InputIterator>
1001        typename enable_if
1002        <
1003           __is_exactly_input_iterator<_InputIterator>::value
1004                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
1005            basic_string&
1006        >::type
1007        assign(_InputIterator __first, _InputIterator __last);
1008    template<class _ForwardIterator>
1009        typename enable_if
1010        <
1011            __is_forward_iterator<_ForwardIterator>::value
1012                 && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
1013            basic_string&
1014        >::type
1015        assign(_ForwardIterator __first, _ForwardIterator __last);
1016#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1017    _LIBCPP_INLINE_VISIBILITY
1018    basic_string& assign(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
1019#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1020
1021    _LIBCPP_INLINE_VISIBILITY
1022    basic_string& insert(size_type __pos1, const basic_string& __str);
1023    _LIBCPP_INLINE_VISIBILITY
1024    basic_string& insert(size_type __pos1, __self_view __sv) { return insert(__pos1, __sv.data(), __sv.size()); }
1025    template <class _Tp>
1026        typename enable_if
1027        <
1028            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1029            basic_string&
1030        >::type
1031                  insert(size_type __pos1, const _Tp& __t, size_type __pos2, size_type __n=npos);
1032    basic_string& insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n=npos);
1033    basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
1034    basic_string& insert(size_type __pos, const value_type* __s);
1035    basic_string& insert(size_type __pos, size_type __n, value_type __c);
1036    iterator      insert(const_iterator __pos, value_type __c);
1037    _LIBCPP_INLINE_VISIBILITY
1038    iterator      insert(const_iterator __pos, size_type __n, value_type __c);
1039    template<class _InputIterator>
1040        typename enable_if
1041        <
1042           __is_exactly_input_iterator<_InputIterator>::value
1043                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
1044            iterator
1045        >::type
1046        insert(const_iterator __pos, _InputIterator __first, _InputIterator __last);
1047    template<class _ForwardIterator>
1048        typename enable_if
1049        <
1050            __is_forward_iterator<_ForwardIterator>::value
1051                 && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
1052            iterator
1053        >::type
1054        insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last);
1055#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1056    _LIBCPP_INLINE_VISIBILITY
1057    iterator insert(const_iterator __pos, initializer_list<value_type> __il)
1058                    {return insert(__pos, __il.begin(), __il.end());}
1059#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1060
1061    basic_string& erase(size_type __pos = 0, size_type __n = npos);
1062    _LIBCPP_INLINE_VISIBILITY
1063    iterator      erase(const_iterator __pos);
1064    _LIBCPP_INLINE_VISIBILITY
1065    iterator      erase(const_iterator __first, const_iterator __last);
1066
1067    _LIBCPP_INLINE_VISIBILITY
1068    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str);
1069    _LIBCPP_INLINE_VISIBILITY
1070    basic_string& replace(size_type __pos1, size_type __n1, __self_view __sv) { return replace(__pos1, __n1, __sv.data(), __sv.size()); }
1071    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos);
1072    template <class _Tp>
1073        typename enable_if
1074        <
1075            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1076            basic_string&
1077        >::type
1078                  replace(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2=npos);
1079    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2);
1080    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s);
1081    basic_string& replace(size_type __pos, size_type __n1, size_type __n2, value_type __c);
1082    _LIBCPP_INLINE_VISIBILITY
1083    basic_string& replace(const_iterator __i1, const_iterator __i2, const basic_string& __str);
1084    _LIBCPP_INLINE_VISIBILITY
1085    basic_string& replace(const_iterator __i1, const_iterator __i2, __self_view __sv) { return replace(__i1 - begin(), __i2 - __i1, __sv); }
1086    _LIBCPP_INLINE_VISIBILITY
1087    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n);
1088    _LIBCPP_INLINE_VISIBILITY
1089    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s);
1090    _LIBCPP_INLINE_VISIBILITY
1091    basic_string& replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c);
1092    template<class _InputIterator>
1093        typename enable_if
1094        <
1095            __is_input_iterator<_InputIterator>::value,
1096            basic_string&
1097        >::type
1098        replace(const_iterator __i1, const_iterator __i2, _InputIterator __j1, _InputIterator __j2);
1099#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1100    _LIBCPP_INLINE_VISIBILITY
1101    basic_string& replace(const_iterator __i1, const_iterator __i2, initializer_list<value_type> __il)
1102        {return replace(__i1, __i2, __il.begin(), __il.end());}
1103#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1104
1105    size_type copy(value_type* __s, size_type __n, size_type __pos = 0) const;
1106    _LIBCPP_INLINE_VISIBILITY
1107    basic_string substr(size_type __pos = 0, size_type __n = npos) const;
1108
1109    _LIBCPP_INLINE_VISIBILITY
1110    void swap(basic_string& __str)
1111#if _LIBCPP_STD_VER >= 14
1112        _NOEXCEPT_DEBUG;
1113#else
1114        _NOEXCEPT_DEBUG_(!__alloc_traits::propagate_on_container_swap::value ||
1115                    __is_nothrow_swappable<allocator_type>::value);
1116#endif
1117
1118    _LIBCPP_INLINE_VISIBILITY
1119    const value_type* c_str() const _NOEXCEPT {return data();}
1120    _LIBCPP_INLINE_VISIBILITY
1121    const value_type* data() const _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
1122#if _LIBCPP_STD_VER > 14
1123    _LIBCPP_INLINE_VISIBILITY
1124    value_type* data()             _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
1125#endif
1126
1127    _LIBCPP_INLINE_VISIBILITY
1128    allocator_type get_allocator() const _NOEXCEPT {return __alloc();}
1129
1130    _LIBCPP_INLINE_VISIBILITY
1131    size_type find(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1132    _LIBCPP_INLINE_VISIBILITY
1133    size_type find(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1134    size_type find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1135    _LIBCPP_INLINE_VISIBILITY
1136    size_type find(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1137    size_type find(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1138
1139    _LIBCPP_INLINE_VISIBILITY
1140    size_type rfind(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1141    _LIBCPP_INLINE_VISIBILITY
1142    size_type rfind(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1143    size_type rfind(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1144    _LIBCPP_INLINE_VISIBILITY
1145    size_type rfind(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1146    size_type rfind(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1147
1148    _LIBCPP_INLINE_VISIBILITY
1149    size_type find_first_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1150    _LIBCPP_INLINE_VISIBILITY
1151    size_type find_first_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1152    size_type find_first_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1153    _LIBCPP_INLINE_VISIBILITY
1154    size_type find_first_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1155    _LIBCPP_INLINE_VISIBILITY
1156    size_type find_first_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1157
1158    _LIBCPP_INLINE_VISIBILITY
1159    size_type find_last_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1160    _LIBCPP_INLINE_VISIBILITY
1161    size_type find_last_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1162    size_type find_last_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1163    _LIBCPP_INLINE_VISIBILITY
1164    size_type find_last_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1165    _LIBCPP_INLINE_VISIBILITY
1166    size_type find_last_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1167
1168    _LIBCPP_INLINE_VISIBILITY
1169    size_type find_first_not_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1170    _LIBCPP_INLINE_VISIBILITY
1171    size_type find_first_not_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1172    size_type find_first_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1173    _LIBCPP_INLINE_VISIBILITY
1174    size_type find_first_not_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1175    _LIBCPP_INLINE_VISIBILITY
1176    size_type find_first_not_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1177
1178    _LIBCPP_INLINE_VISIBILITY
1179    size_type find_last_not_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1180    _LIBCPP_INLINE_VISIBILITY
1181    size_type find_last_not_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1182    size_type find_last_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1183    _LIBCPP_INLINE_VISIBILITY
1184    size_type find_last_not_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1185    _LIBCPP_INLINE_VISIBILITY
1186    size_type find_last_not_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1187
1188    _LIBCPP_INLINE_VISIBILITY
1189    int compare(const basic_string& __str) const _NOEXCEPT;
1190    _LIBCPP_INLINE_VISIBILITY
1191    int compare(__self_view __sv) const _NOEXCEPT;
1192    _LIBCPP_INLINE_VISIBILITY
1193    int compare(size_type __pos1, size_type __n1, __self_view __sv) const;
1194    _LIBCPP_INLINE_VISIBILITY
1195    int compare(size_type __pos1, size_type __n1, const basic_string& __str) const;
1196    int compare(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos) const;
1197    template <class _Tp>
1198    inline _LIBCPP_INLINE_VISIBILITY
1199        typename enable_if
1200        <
1201            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1202            int
1203        >::type
1204        compare(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2=npos) const;
1205    int compare(const value_type* __s) const _NOEXCEPT;
1206    int compare(size_type __pos1, size_type __n1, const value_type* __s) const;
1207    int compare(size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const;
1208
1209    _LIBCPP_INLINE_VISIBILITY bool __invariants() const;
1210
1211    _LIBCPP_INLINE_VISIBILITY
1212    bool __is_long() const _NOEXCEPT
1213        {return bool(__r_.first().__s.__size_ & __short_mask);}
1214
1215#if _LIBCPP_DEBUG_LEVEL >= 2
1216
1217    bool __dereferenceable(const const_iterator* __i) const;
1218    bool __decrementable(const const_iterator* __i) const;
1219    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
1220    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
1221
1222#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1223
1224private:
1225    _LIBCPP_INLINE_VISIBILITY
1226    allocator_type& __alloc() _NOEXCEPT
1227        {return __r_.second();}
1228    _LIBCPP_INLINE_VISIBILITY
1229    const allocator_type& __alloc() const _NOEXCEPT
1230        {return __r_.second();}
1231
1232#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1233
1234    _LIBCPP_INLINE_VISIBILITY
1235    void __set_short_size(size_type __s) _NOEXCEPT
1236#   if _LIBCPP_BIG_ENDIAN
1237        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1238#   else
1239        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1240#   endif
1241
1242    _LIBCPP_INLINE_VISIBILITY
1243    size_type __get_short_size() const _NOEXCEPT
1244#   if _LIBCPP_BIG_ENDIAN
1245        {return __r_.first().__s.__size_ >> 1;}
1246#   else
1247        {return __r_.first().__s.__size_;}
1248#   endif
1249
1250#else  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1251
1252    _LIBCPP_INLINE_VISIBILITY
1253    void __set_short_size(size_type __s) _NOEXCEPT
1254#   if _LIBCPP_BIG_ENDIAN
1255        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1256#   else
1257        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1258#   endif
1259
1260    _LIBCPP_INLINE_VISIBILITY
1261    size_type __get_short_size() const _NOEXCEPT
1262#   if _LIBCPP_BIG_ENDIAN
1263        {return __r_.first().__s.__size_;}
1264#   else
1265        {return __r_.first().__s.__size_ >> 1;}
1266#   endif
1267
1268#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1269
1270    _LIBCPP_INLINE_VISIBILITY
1271    void __set_long_size(size_type __s) _NOEXCEPT
1272        {__r_.first().__l.__size_ = __s;}
1273    _LIBCPP_INLINE_VISIBILITY
1274    size_type __get_long_size() const _NOEXCEPT
1275        {return __r_.first().__l.__size_;}
1276    _LIBCPP_INLINE_VISIBILITY
1277    void __set_size(size_type __s) _NOEXCEPT
1278        {if (__is_long()) __set_long_size(__s); else __set_short_size(__s);}
1279
1280    _LIBCPP_INLINE_VISIBILITY
1281    void __set_long_cap(size_type __s) _NOEXCEPT
1282        {__r_.first().__l.__cap_  = __long_mask | __s;}
1283    _LIBCPP_INLINE_VISIBILITY
1284    size_type __get_long_cap() const _NOEXCEPT
1285        {return __r_.first().__l.__cap_ & size_type(~__long_mask);}
1286
1287    _LIBCPP_INLINE_VISIBILITY
1288    void __set_long_pointer(pointer __p) _NOEXCEPT
1289        {__r_.first().__l.__data_ = __p;}
1290    _LIBCPP_INLINE_VISIBILITY
1291    pointer __get_long_pointer() _NOEXCEPT
1292        {return __r_.first().__l.__data_;}
1293    _LIBCPP_INLINE_VISIBILITY
1294    const_pointer __get_long_pointer() const _NOEXCEPT
1295        {return __r_.first().__l.__data_;}
1296    _LIBCPP_INLINE_VISIBILITY
1297    pointer __get_short_pointer() _NOEXCEPT
1298        {return pointer_traits<pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1299    _LIBCPP_INLINE_VISIBILITY
1300    const_pointer __get_short_pointer() const _NOEXCEPT
1301        {return pointer_traits<const_pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1302    _LIBCPP_INLINE_VISIBILITY
1303    pointer __get_pointer() _NOEXCEPT
1304        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1305    _LIBCPP_INLINE_VISIBILITY
1306    const_pointer __get_pointer() const _NOEXCEPT
1307        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1308
1309    _LIBCPP_INLINE_VISIBILITY
1310    void __zero() _NOEXCEPT
1311        {
1312            size_type (&__a)[__n_words] = __r_.first().__r.__words;
1313            for (unsigned __i = 0; __i < __n_words; ++__i)
1314                __a[__i] = 0;
1315        }
1316
1317    template <size_type __a> static
1318        _LIBCPP_INLINE_VISIBILITY
1319        size_type __align_it(size_type __s) _NOEXCEPT
1320            {return (__s + (__a-1)) & ~(__a-1);}
1321    enum {__alignment = 16};
1322    static _LIBCPP_INLINE_VISIBILITY
1323    size_type __recommend(size_type __s) _NOEXCEPT
1324        {return (__s < __min_cap ? static_cast<size_type>(__min_cap) :
1325                 __align_it<sizeof(value_type) < __alignment ?
1326                            __alignment/sizeof(value_type) : 1 > (__s+1)) - 1;}
1327
1328    inline _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
1329    void __init(const value_type* __s, size_type __sz, size_type __reserve);
1330    inline _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
1331    void __init(const value_type* __s, size_type __sz);
1332    inline _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
1333    void __init(size_type __n, value_type __c);
1334
1335    template <class _InputIterator>
1336    inline _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
1337    typename enable_if
1338    <
1339        __is_exactly_input_iterator<_InputIterator>::value,
1340        void
1341    >::type
1342    __init(_InputIterator __first, _InputIterator __last);
1343
1344    template <class _ForwardIterator>
1345    inline _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
1346    typename enable_if
1347    <
1348        __is_forward_iterator<_ForwardIterator>::value,
1349        void
1350    >::type
1351    __init(_ForwardIterator __first, _ForwardIterator __last);
1352
1353    void __grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1354                   size_type __n_copy,  size_type __n_del,     size_type __n_add = 0);
1355    void __grow_by_and_replace(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1356                               size_type __n_copy,  size_type __n_del,
1357                               size_type __n_add, const value_type* __p_new_stuff);
1358
1359    _LIBCPP_INLINE_VISIBILITY
1360    void __erase_to_end(size_type __pos);
1361
1362    _LIBCPP_INLINE_VISIBILITY
1363    void __copy_assign_alloc(const basic_string& __str)
1364        {__copy_assign_alloc(__str, integral_constant<bool,
1365                      __alloc_traits::propagate_on_container_copy_assignment::value>());}
1366
1367    _LIBCPP_INLINE_VISIBILITY
1368    void __copy_assign_alloc(const basic_string& __str, true_type)
1369        {
1370            if (__alloc() != __str.__alloc())
1371            {
1372                clear();
1373                shrink_to_fit();
1374            }
1375            __alloc() = __str.__alloc();
1376        }
1377
1378    _LIBCPP_INLINE_VISIBILITY
1379    void __copy_assign_alloc(const basic_string&, false_type) _NOEXCEPT
1380        {}
1381
1382#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1383    _LIBCPP_INLINE_VISIBILITY
1384    void __move_assign(basic_string& __str, false_type)
1385        _NOEXCEPT_(__alloc_traits::is_always_equal::value);
1386    _LIBCPP_INLINE_VISIBILITY
1387    void __move_assign(basic_string& __str, true_type)
1388#if _LIBCPP_STD_VER > 14
1389        _NOEXCEPT;
1390#else
1391        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
1392#endif
1393#endif
1394
1395    _LIBCPP_INLINE_VISIBILITY
1396    void
1397    __move_assign_alloc(basic_string& __str)
1398        _NOEXCEPT_(
1399            !__alloc_traits::propagate_on_container_move_assignment::value ||
1400            is_nothrow_move_assignable<allocator_type>::value)
1401    {__move_assign_alloc(__str, integral_constant<bool,
1402                      __alloc_traits::propagate_on_container_move_assignment::value>());}
1403
1404    _LIBCPP_INLINE_VISIBILITY
1405    void __move_assign_alloc(basic_string& __c, true_type)
1406        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1407        {
1408            __alloc() = _VSTD::move(__c.__alloc());
1409        }
1410
1411    _LIBCPP_INLINE_VISIBILITY
1412    void __move_assign_alloc(basic_string&, false_type)
1413        _NOEXCEPT
1414        {}
1415
1416    _LIBCPP_INLINE_VISIBILITY void __invalidate_all_iterators();
1417    _LIBCPP_INLINE_VISIBILITY void __invalidate_iterators_past(size_type);
1418
1419    friend basic_string operator+<>(const basic_string&, const basic_string&);
1420    friend basic_string operator+<>(const value_type*, const basic_string&);
1421    friend basic_string operator+<>(value_type, const basic_string&);
1422    friend basic_string operator+<>(const basic_string&, const value_type*);
1423    friend basic_string operator+<>(const basic_string&, value_type);
1424};
1425
1426template <class _CharT, class _Traits, class _Allocator>
1427inline _LIBCPP_INLINE_VISIBILITY
1428void
1429basic_string<_CharT, _Traits, _Allocator>::__invalidate_all_iterators()
1430{
1431#if _LIBCPP_DEBUG_LEVEL >= 2
1432    __get_db()->__invalidate_all(this);
1433#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1434}
1435
1436template <class _CharT, class _Traits, class _Allocator>
1437inline _LIBCPP_INLINE_VISIBILITY
1438void
1439basic_string<_CharT, _Traits, _Allocator>::__invalidate_iterators_past(size_type
1440#if _LIBCPP_DEBUG_LEVEL >= 2
1441                                                                        __pos
1442#endif
1443                                                                      )
1444{
1445#if _LIBCPP_DEBUG_LEVEL >= 2
1446    __c_node* __c = __get_db()->__find_c_and_lock(this);
1447    if (__c)
1448    {
1449        const_pointer __new_last = __get_pointer() + __pos;
1450        for (__i_node** __p = __c->end_; __p != __c->beg_; )
1451        {
1452            --__p;
1453            const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
1454            if (__i->base() > __new_last)
1455            {
1456                (*__p)->__c_ = nullptr;
1457                if (--__c->end_ != __p)
1458                    memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
1459            }
1460        }
1461        __get_db()->unlock();
1462    }
1463#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1464}
1465
1466template <class _CharT, class _Traits, class _Allocator>
1467inline _LIBCPP_INLINE_VISIBILITY
1468basic_string<_CharT, _Traits, _Allocator>::basic_string()
1469    _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
1470{
1471#if _LIBCPP_DEBUG_LEVEL >= 2
1472    __get_db()->__insert_c(this);
1473#endif
1474    __zero();
1475}
1476
1477template <class _CharT, class _Traits, class _Allocator>
1478inline _LIBCPP_INLINE_VISIBILITY
1479basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __a)
1480#if _LIBCPP_STD_VER <= 14
1481        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
1482#else
1483        _NOEXCEPT
1484#endif
1485: __r_(__a)
1486{
1487#if _LIBCPP_DEBUG_LEVEL >= 2
1488    __get_db()->__insert_c(this);
1489#endif
1490    __zero();
1491}
1492
1493template <class _CharT, class _Traits, class _Allocator>
1494void basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s,
1495                                                       size_type __sz,
1496                                                       size_type __reserve)
1497{
1498    if (__reserve > max_size())
1499        this->__throw_length_error();
1500    pointer __p;
1501    if (__reserve < __min_cap)
1502    {
1503        __set_short_size(__sz);
1504        __p = __get_short_pointer();
1505    }
1506    else
1507    {
1508        size_type __cap = __recommend(__reserve);
1509        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1510        __set_long_pointer(__p);
1511        __set_long_cap(__cap+1);
1512        __set_long_size(__sz);
1513    }
1514    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
1515    traits_type::assign(__p[__sz], value_type());
1516}
1517
1518template <class _CharT, class _Traits, class _Allocator>
1519void
1520basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz)
1521{
1522    if (__sz > max_size())
1523        this->__throw_length_error();
1524    pointer __p;
1525    if (__sz < __min_cap)
1526    {
1527        __set_short_size(__sz);
1528        __p = __get_short_pointer();
1529    }
1530    else
1531    {
1532        size_type __cap = __recommend(__sz);
1533        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1534        __set_long_pointer(__p);
1535        __set_long_cap(__cap+1);
1536        __set_long_size(__sz);
1537    }
1538    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
1539    traits_type::assign(__p[__sz], value_type());
1540}
1541
1542template <class _CharT, class _Traits, class _Allocator>
1543inline _LIBCPP_INLINE_VISIBILITY
1544basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s)
1545{
1546    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*) detected nullptr");
1547    __init(__s, traits_type::length(__s));
1548#if _LIBCPP_DEBUG_LEVEL >= 2
1549    __get_db()->__insert_c(this);
1550#endif
1551}
1552
1553template <class _CharT, class _Traits, class _Allocator>
1554inline _LIBCPP_INLINE_VISIBILITY
1555basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, const allocator_type& __a)
1556    : __r_(__a)
1557{
1558    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*, allocator) detected nullptr");
1559    __init(__s, traits_type::length(__s));
1560#if _LIBCPP_DEBUG_LEVEL >= 2
1561    __get_db()->__insert_c(this);
1562#endif
1563}
1564
1565template <class _CharT, class _Traits, class _Allocator>
1566inline _LIBCPP_INLINE_VISIBILITY
1567basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n)
1568{
1569    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n) detected nullptr");
1570    __init(__s, __n);
1571#if _LIBCPP_DEBUG_LEVEL >= 2
1572    __get_db()->__insert_c(this);
1573#endif
1574}
1575
1576template <class _CharT, class _Traits, class _Allocator>
1577inline _LIBCPP_INLINE_VISIBILITY
1578basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n, const allocator_type& __a)
1579    : __r_(__a)
1580{
1581    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n, allocator) detected nullptr");
1582    __init(__s, __n);
1583#if _LIBCPP_DEBUG_LEVEL >= 2
1584    __get_db()->__insert_c(this);
1585#endif
1586}
1587
1588template <class _CharT, class _Traits, class _Allocator>
1589basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str)
1590    : __r_(__alloc_traits::select_on_container_copy_construction(__str.__alloc()))
1591{
1592    if (!__str.__is_long())
1593        __r_.first().__r = __str.__r_.first().__r;
1594    else
1595        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1596#if _LIBCPP_DEBUG_LEVEL >= 2
1597    __get_db()->__insert_c(this);
1598#endif
1599}
1600
1601template <class _CharT, class _Traits, class _Allocator>
1602basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, const allocator_type& __a)
1603    : __r_(__a)
1604{
1605    if (!__str.__is_long())
1606        __r_.first().__r = __str.__r_.first().__r;
1607    else
1608        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1609#if _LIBCPP_DEBUG_LEVEL >= 2
1610    __get_db()->__insert_c(this);
1611#endif
1612}
1613
1614#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1615
1616template <class _CharT, class _Traits, class _Allocator>
1617inline _LIBCPP_INLINE_VISIBILITY
1618basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str)
1619#if _LIBCPP_STD_VER <= 14
1620        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
1621#else
1622        _NOEXCEPT
1623#endif
1624    : __r_(_VSTD::move(__str.__r_))
1625{
1626    __str.__zero();
1627#if _LIBCPP_DEBUG_LEVEL >= 2
1628    __get_db()->__insert_c(this);
1629    if (__is_long())
1630        __get_db()->swap(this, &__str);
1631#endif
1632}
1633
1634template <class _CharT, class _Traits, class _Allocator>
1635inline _LIBCPP_INLINE_VISIBILITY
1636basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str, const allocator_type& __a)
1637    : __r_(__a)
1638{
1639    if (__str.__is_long() && __a != __str.__alloc()) // copy, not move
1640        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1641    else
1642    {
1643        __r_.first().__r = __str.__r_.first().__r;
1644        __str.__zero();
1645    }
1646#if _LIBCPP_DEBUG_LEVEL >= 2
1647    __get_db()->__insert_c(this);
1648    if (__is_long())
1649        __get_db()->swap(this, &__str);
1650#endif
1651}
1652
1653#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1654
1655template <class _CharT, class _Traits, class _Allocator>
1656void
1657basic_string<_CharT, _Traits, _Allocator>::__init(size_type __n, value_type __c)
1658{
1659    if (__n > max_size())
1660        this->__throw_length_error();
1661    pointer __p;
1662    if (__n < __min_cap)
1663    {
1664        __set_short_size(__n);
1665        __p = __get_short_pointer();
1666    }
1667    else
1668    {
1669        size_type __cap = __recommend(__n);
1670        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1671        __set_long_pointer(__p);
1672        __set_long_cap(__cap+1);
1673        __set_long_size(__n);
1674    }
1675    traits_type::assign(_VSTD::__to_raw_pointer(__p), __n, __c);
1676    traits_type::assign(__p[__n], value_type());
1677}
1678
1679template <class _CharT, class _Traits, class _Allocator>
1680inline _LIBCPP_INLINE_VISIBILITY
1681basic_string<_CharT, _Traits, _Allocator>::basic_string(size_type __n, value_type __c)
1682{
1683    __init(__n, __c);
1684#if _LIBCPP_DEBUG_LEVEL >= 2
1685    __get_db()->__insert_c(this);
1686#endif
1687}
1688
1689template <class _CharT, class _Traits, class _Allocator>
1690inline _LIBCPP_INLINE_VISIBILITY
1691basic_string<_CharT, _Traits, _Allocator>::basic_string(size_type __n, value_type __c, const allocator_type& __a)
1692    : __r_(__a)
1693{
1694    __init(__n, __c);
1695#if _LIBCPP_DEBUG_LEVEL >= 2
1696    __get_db()->__insert_c(this);
1697#endif
1698}
1699
1700template <class _CharT, class _Traits, class _Allocator>
1701basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, size_type __pos, size_type __n,
1702                                                        const allocator_type& __a)
1703    : __r_(__a)
1704{
1705    size_type __str_sz = __str.size();
1706    if (__pos > __str_sz)
1707        this->__throw_out_of_range();
1708    __init(__str.data() + __pos, _VSTD::min(__n, __str_sz - __pos));
1709#if _LIBCPP_DEBUG_LEVEL >= 2
1710    __get_db()->__insert_c(this);
1711#endif
1712}
1713
1714template <class _CharT, class _Traits, class _Allocator>
1715inline _LIBCPP_INLINE_VISIBILITY
1716basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, size_type __pos,
1717                                                        const allocator_type& __a)
1718    : __r_(__a)
1719{
1720    size_type __str_sz = __str.size();
1721    if (__pos > __str_sz)
1722        this->__throw_out_of_range();
1723    __init(__str.data() + __pos, __str_sz - __pos);
1724#if _LIBCPP_DEBUG_LEVEL >= 2
1725    __get_db()->__insert_c(this);
1726#endif
1727}
1728
1729template <class _CharT, class _Traits, class _Allocator>
1730template <class _Tp>
1731basic_string<_CharT, _Traits, _Allocator>::basic_string(
1732             const _Tp& __t, size_type __pos, size_type __n, const allocator_type& __a,
1733			 typename enable_if<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, void>::type *)
1734    : __r_(__a)
1735{
1736	__self_view __sv = __self_view(__t).substr(__pos, __n);
1737    __init(__sv.data(), __sv.size());
1738#if _LIBCPP_DEBUG_LEVEL >= 2
1739    __get_db()->__insert_c(this);
1740#endif
1741}
1742
1743template <class _CharT, class _Traits, class _Allocator>
1744inline _LIBCPP_INLINE_VISIBILITY
1745basic_string<_CharT, _Traits, _Allocator>::basic_string(__self_view __sv)
1746{
1747    __init(__sv.data(), __sv.size());
1748#if _LIBCPP_DEBUG_LEVEL >= 2
1749    __get_db()->__insert_c(this);
1750#endif
1751}
1752
1753template <class _CharT, class _Traits, class _Allocator>
1754inline _LIBCPP_INLINE_VISIBILITY
1755basic_string<_CharT, _Traits, _Allocator>::basic_string(__self_view __sv, const allocator_type& __a)
1756    : __r_(__a)
1757{
1758    __init(__sv.data(), __sv.size());
1759#if _LIBCPP_DEBUG_LEVEL >= 2
1760    __get_db()->__insert_c(this);
1761#endif
1762}
1763
1764template <class _CharT, class _Traits, class _Allocator>
1765template <class _InputIterator>
1766typename enable_if
1767<
1768    __is_exactly_input_iterator<_InputIterator>::value,
1769    void
1770>::type
1771basic_string<_CharT, _Traits, _Allocator>::__init(_InputIterator __first, _InputIterator __last)
1772{
1773    __zero();
1774#ifndef _LIBCPP_NO_EXCEPTIONS
1775    try
1776    {
1777#endif  // _LIBCPP_NO_EXCEPTIONS
1778    for (; __first != __last; ++__first)
1779        push_back(*__first);
1780#ifndef _LIBCPP_NO_EXCEPTIONS
1781    }
1782    catch (...)
1783    {
1784        if (__is_long())
1785            __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
1786        throw;
1787    }
1788#endif  // _LIBCPP_NO_EXCEPTIONS
1789}
1790
1791template <class _CharT, class _Traits, class _Allocator>
1792template <class _ForwardIterator>
1793typename enable_if
1794<
1795    __is_forward_iterator<_ForwardIterator>::value,
1796    void
1797>::type
1798basic_string<_CharT, _Traits, _Allocator>::__init(_ForwardIterator __first, _ForwardIterator __last)
1799{
1800    size_type __sz = static_cast<size_type>(_VSTD::distance(__first, __last));
1801    if (__sz > max_size())
1802        this->__throw_length_error();
1803    pointer __p;
1804    if (__sz < __min_cap)
1805    {
1806        __set_short_size(__sz);
1807        __p = __get_short_pointer();
1808    }
1809    else
1810    {
1811        size_type __cap = __recommend(__sz);
1812        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1813        __set_long_pointer(__p);
1814        __set_long_cap(__cap+1);
1815        __set_long_size(__sz);
1816    }
1817    for (; __first != __last; ++__first, (void) ++__p)
1818        traits_type::assign(*__p, *__first);
1819    traits_type::assign(*__p, value_type());
1820}
1821
1822template <class _CharT, class _Traits, class _Allocator>
1823template<class _InputIterator>
1824inline _LIBCPP_INLINE_VISIBILITY
1825basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last)
1826{
1827    __init(__first, __last);
1828#if _LIBCPP_DEBUG_LEVEL >= 2
1829    __get_db()->__insert_c(this);
1830#endif
1831}
1832
1833template <class _CharT, class _Traits, class _Allocator>
1834template<class _InputIterator>
1835inline _LIBCPP_INLINE_VISIBILITY
1836basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last,
1837                                                        const allocator_type& __a)
1838    : __r_(__a)
1839{
1840    __init(__first, __last);
1841#if _LIBCPP_DEBUG_LEVEL >= 2
1842    __get_db()->__insert_c(this);
1843#endif
1844}
1845
1846#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1847
1848template <class _CharT, class _Traits, class _Allocator>
1849inline _LIBCPP_INLINE_VISIBILITY
1850basic_string<_CharT, _Traits, _Allocator>::basic_string(initializer_list<value_type> __il)
1851{
1852    __init(__il.begin(), __il.end());
1853#if _LIBCPP_DEBUG_LEVEL >= 2
1854    __get_db()->__insert_c(this);
1855#endif
1856}
1857
1858template <class _CharT, class _Traits, class _Allocator>
1859inline _LIBCPP_INLINE_VISIBILITY
1860basic_string<_CharT, _Traits, _Allocator>::basic_string(initializer_list<value_type> __il, const allocator_type& __a)
1861    : __r_(__a)
1862{
1863    __init(__il.begin(), __il.end());
1864#if _LIBCPP_DEBUG_LEVEL >= 2
1865    __get_db()->__insert_c(this);
1866#endif
1867}
1868
1869#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1870
1871template <class _CharT, class _Traits, class _Allocator>
1872basic_string<_CharT, _Traits, _Allocator>::~basic_string()
1873{
1874#if _LIBCPP_DEBUG_LEVEL >= 2
1875    __get_db()->__erase_c(this);
1876#endif
1877    if (__is_long())
1878        __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
1879}
1880
1881template <class _CharT, class _Traits, class _Allocator>
1882void
1883basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace
1884    (size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1885     size_type __n_copy,  size_type __n_del,     size_type __n_add, const value_type* __p_new_stuff)
1886{
1887    size_type __ms = max_size();
1888    if (__delta_cap > __ms - __old_cap - 1)
1889        this->__throw_length_error();
1890    pointer __old_p = __get_pointer();
1891    size_type __cap = __old_cap < __ms / 2 - __alignment ?
1892                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
1893                          __ms - 1;
1894    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
1895    __invalidate_all_iterators();
1896    if (__n_copy != 0)
1897        traits_type::copy(_VSTD::__to_raw_pointer(__p),
1898                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
1899    if (__n_add != 0)
1900        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy, __p_new_stuff, __n_add);
1901    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
1902    if (__sec_cp_sz != 0)
1903        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
1904                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del, __sec_cp_sz);
1905    if (__old_cap+1 != __min_cap)
1906        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
1907    __set_long_pointer(__p);
1908    __set_long_cap(__cap+1);
1909    __old_sz = __n_copy + __n_add + __sec_cp_sz;
1910    __set_long_size(__old_sz);
1911    traits_type::assign(__p[__old_sz], value_type());
1912}
1913
1914template <class _CharT, class _Traits, class _Allocator>
1915void
1916basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1917                                                     size_type __n_copy,  size_type __n_del,     size_type __n_add)
1918{
1919    size_type __ms = max_size();
1920    if (__delta_cap > __ms - __old_cap)
1921        this->__throw_length_error();
1922    pointer __old_p = __get_pointer();
1923    size_type __cap = __old_cap < __ms / 2 - __alignment ?
1924                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
1925                          __ms - 1;
1926    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
1927    __invalidate_all_iterators();
1928    if (__n_copy != 0)
1929        traits_type::copy(_VSTD::__to_raw_pointer(__p),
1930                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
1931    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
1932    if (__sec_cp_sz != 0)
1933        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
1934                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del,
1935                          __sec_cp_sz);
1936    if (__old_cap+1 != __min_cap)
1937        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
1938    __set_long_pointer(__p);
1939    __set_long_cap(__cap+1);
1940}
1941
1942// assign
1943
1944template <class _CharT, class _Traits, class _Allocator>
1945basic_string<_CharT, _Traits, _Allocator>&
1946basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n)
1947{
1948    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::assign received nullptr");
1949    size_type __cap = capacity();
1950    if (__cap >= __n)
1951    {
1952        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
1953        traits_type::move(__p, __s, __n);
1954        traits_type::assign(__p[__n], value_type());
1955        __set_size(__n);
1956        __invalidate_iterators_past(__n);
1957    }
1958    else
1959    {
1960        size_type __sz = size();
1961        __grow_by_and_replace(__cap, __n - __cap, __sz, 0, __sz, __n, __s);
1962    }
1963    return *this;
1964}
1965
1966template <class _CharT, class _Traits, class _Allocator>
1967basic_string<_CharT, _Traits, _Allocator>&
1968basic_string<_CharT, _Traits, _Allocator>::assign(size_type __n, value_type __c)
1969{
1970    size_type __cap = capacity();
1971    if (__cap < __n)
1972    {
1973        size_type __sz = size();
1974        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
1975    }
1976    else
1977        __invalidate_iterators_past(__n);
1978    value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
1979    traits_type::assign(__p, __n, __c);
1980    traits_type::assign(__p[__n], value_type());
1981    __set_size(__n);
1982    return *this;
1983}
1984
1985template <class _CharT, class _Traits, class _Allocator>
1986basic_string<_CharT, _Traits, _Allocator>&
1987basic_string<_CharT, _Traits, _Allocator>::operator=(value_type __c)
1988{
1989    pointer __p;
1990    if (__is_long())
1991    {
1992        __p = __get_long_pointer();
1993        __set_long_size(1);
1994    }
1995    else
1996    {
1997        __p = __get_short_pointer();
1998        __set_short_size(1);
1999    }
2000    traits_type::assign(*__p, __c);
2001    traits_type::assign(*++__p, value_type());
2002    __invalidate_iterators_past(1);
2003    return *this;
2004}
2005
2006template <class _CharT, class _Traits, class _Allocator>
2007basic_string<_CharT, _Traits, _Allocator>&
2008basic_string<_CharT, _Traits, _Allocator>::operator=(const basic_string& __str)
2009{
2010    if (this != &__str)
2011    {
2012        __copy_assign_alloc(__str);
2013        assign(__str.data(), __str.size());
2014    }
2015    return *this;
2016}
2017
2018#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2019
2020template <class _CharT, class _Traits, class _Allocator>
2021inline _LIBCPP_INLINE_VISIBILITY
2022void
2023basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, false_type)
2024    _NOEXCEPT_(__alloc_traits::is_always_equal::value)
2025{
2026    if (__alloc() != __str.__alloc())
2027        assign(__str);
2028    else
2029        __move_assign(__str, true_type());
2030}
2031
2032template <class _CharT, class _Traits, class _Allocator>
2033inline _LIBCPP_INLINE_VISIBILITY
2034void
2035basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, true_type)
2036#if _LIBCPP_STD_VER > 14
2037    _NOEXCEPT
2038#else
2039    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
2040#endif
2041{
2042    clear();
2043    shrink_to_fit();
2044    __r_.first() = __str.__r_.first();
2045    __move_assign_alloc(__str);
2046    __str.__zero();
2047}
2048
2049template <class _CharT, class _Traits, class _Allocator>
2050inline _LIBCPP_INLINE_VISIBILITY
2051basic_string<_CharT, _Traits, _Allocator>&
2052basic_string<_CharT, _Traits, _Allocator>::operator=(basic_string&& __str)
2053    _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value))
2054{
2055    __move_assign(__str, integral_constant<bool,
2056          __alloc_traits::propagate_on_container_move_assignment::value>());
2057    return *this;
2058}
2059
2060#endif
2061
2062template <class _CharT, class _Traits, class _Allocator>
2063template<class _InputIterator>
2064typename enable_if
2065<
2066     __is_exactly_input_iterator <_InputIterator>::value
2067          || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
2068    basic_string<_CharT, _Traits, _Allocator>&
2069>::type
2070basic_string<_CharT, _Traits, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
2071{
2072    const basic_string __temp(__first, __last, __alloc());
2073    assign(__temp.data(), __temp.size());
2074    return *this;
2075}
2076
2077template <class _CharT, class _Traits, class _Allocator>
2078template<class _ForwardIterator>
2079typename enable_if
2080<
2081    __is_forward_iterator<_ForwardIterator>::value
2082         && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
2083    basic_string<_CharT, _Traits, _Allocator>&
2084>::type
2085basic_string<_CharT, _Traits, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last)
2086{
2087    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2088    size_type __cap = capacity();
2089    if (__cap < __n)
2090    {
2091        size_type __sz = size();
2092        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
2093    }
2094    else
2095        __invalidate_iterators_past(__n);
2096    pointer __p = __get_pointer();
2097    for (; __first != __last; ++__first, ++__p)
2098        traits_type::assign(*__p, *__first);
2099    traits_type::assign(*__p, value_type());
2100    __set_size(__n);
2101    return *this;
2102}
2103
2104template <class _CharT, class _Traits, class _Allocator>
2105basic_string<_CharT, _Traits, _Allocator>&
2106basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str, size_type __pos, size_type __n)
2107{
2108    size_type __sz = __str.size();
2109    if (__pos > __sz)
2110        this->__throw_out_of_range();
2111    return assign(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2112}
2113
2114template <class _CharT, class _Traits, class _Allocator>
2115template <class _Tp>
2116typename enable_if
2117<
2118    __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2119	basic_string<_CharT, _Traits, _Allocator>&
2120>::type
2121basic_string<_CharT, _Traits, _Allocator>::assign(const _Tp & __t, size_type __pos, size_type __n)
2122{
2123    __self_view __sv = __t;
2124    size_type __sz = __sv.size();
2125    if (__pos > __sz)
2126        this->__throw_out_of_range();
2127    return assign(__sv.data() + __pos, _VSTD::min(__n, __sz - __pos));
2128}
2129
2130
2131template <class _CharT, class _Traits, class _Allocator>
2132basic_string<_CharT, _Traits, _Allocator>&
2133basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s)
2134{
2135    _LIBCPP_ASSERT(__s != nullptr, "string::assign received nullptr");
2136    return assign(__s, traits_type::length(__s));
2137}
2138
2139// append
2140
2141template <class _CharT, class _Traits, class _Allocator>
2142basic_string<_CharT, _Traits, _Allocator>&
2143basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s, size_type __n)
2144{
2145    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::append received nullptr");
2146    size_type __cap = capacity();
2147    size_type __sz = size();
2148    if (__cap - __sz >= __n)
2149    {
2150        if (__n)
2151        {
2152            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2153            traits_type::copy(__p + __sz, __s, __n);
2154            __sz += __n;
2155            __set_size(__sz);
2156            traits_type::assign(__p[__sz], value_type());
2157        }
2158    }
2159    else
2160        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __sz, 0, __n, __s);
2161    return *this;
2162}
2163
2164template <class _CharT, class _Traits, class _Allocator>
2165basic_string<_CharT, _Traits, _Allocator>&
2166basic_string<_CharT, _Traits, _Allocator>::append(size_type __n, value_type __c)
2167{
2168    if (__n)
2169    {
2170        size_type __cap = capacity();
2171        size_type __sz = size();
2172        if (__cap - __sz < __n)
2173            __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2174        pointer __p = __get_pointer();
2175        traits_type::assign(_VSTD::__to_raw_pointer(__p) + __sz, __n, __c);
2176        __sz += __n;
2177        __set_size(__sz);
2178        traits_type::assign(__p[__sz], value_type());
2179    }
2180    return *this;
2181}
2182
2183template <class _CharT, class _Traits, class _Allocator>
2184void
2185basic_string<_CharT, _Traits, _Allocator>::push_back(value_type __c)
2186{
2187    bool __is_short = !__is_long();
2188    size_type __cap;
2189    size_type __sz;
2190    if (__is_short)
2191    {
2192        __cap = __min_cap - 1;
2193        __sz = __get_short_size();
2194    }
2195    else
2196    {
2197        __cap = __get_long_cap() - 1;
2198        __sz = __get_long_size();
2199    }
2200    if (__sz == __cap)
2201    {
2202        __grow_by(__cap, 1, __sz, __sz, 0);
2203        __is_short = !__is_long();
2204    }
2205    pointer __p;
2206    if (__is_short)
2207    {
2208        __p = __get_short_pointer() + __sz;
2209        __set_short_size(__sz+1);
2210    }
2211    else
2212    {
2213        __p = __get_long_pointer() + __sz;
2214        __set_long_size(__sz+1);
2215    }
2216    traits_type::assign(*__p, __c);
2217    traits_type::assign(*++__p, value_type());
2218}
2219
2220template <class _Tp>
2221bool __ptr_in_range (const _Tp* __p, const _Tp* __first, const _Tp* __last)
2222{
2223    return __first <= __p && __p < __last;
2224}
2225
2226template <class _Tp1, class _Tp2>
2227bool __ptr_in_range (const _Tp1*, const _Tp2*, const _Tp2*)
2228{
2229    return false;
2230}
2231
2232template <class _CharT, class _Traits, class _Allocator>
2233template<class _ForwardIterator>
2234basic_string<_CharT, _Traits, _Allocator>&
2235basic_string<_CharT, _Traits, _Allocator>::__append_forward_unsafe(
2236    _ForwardIterator __first, _ForwardIterator __last)
2237{
2238    static_assert(__is_forward_iterator<_ForwardIterator>::value,
2239                  "function requires a ForwardIterator");
2240    size_type __sz = size();
2241    size_type __cap = capacity();
2242    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2243    if (__n)
2244    {
2245        if ( __ptr_in_range(&*__first, data(), data() + size()))
2246        {
2247            const basic_string __temp (__first, __last, __alloc());
2248            append(__temp.data(), __temp.size());
2249        }
2250        else
2251        {
2252            if (__cap - __sz < __n)
2253                __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2254            pointer __p = __get_pointer() + __sz;
2255            for (; __first != __last; ++__p, ++__first)
2256                traits_type::assign(*__p, *__first);
2257            traits_type::assign(*__p, value_type());
2258            __set_size(__sz + __n);
2259        }
2260    }
2261    return *this;
2262}
2263
2264template <class _CharT, class _Traits, class _Allocator>
2265inline _LIBCPP_INLINE_VISIBILITY
2266basic_string<_CharT, _Traits, _Allocator>&
2267basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str)
2268{
2269    return append(__str.data(), __str.size());
2270}
2271
2272template <class _CharT, class _Traits, class _Allocator>
2273basic_string<_CharT, _Traits, _Allocator>&
2274basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str, size_type __pos, size_type __n)
2275{
2276    size_type __sz = __str.size();
2277    if (__pos > __sz)
2278        this->__throw_out_of_range();
2279    return append(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2280}
2281
2282template <class _CharT, class _Traits, class _Allocator>
2283template <class _Tp>
2284    typename enable_if
2285    <
2286        __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2287        basic_string<_CharT, _Traits, _Allocator>&
2288    >::type
2289basic_string<_CharT, _Traits, _Allocator>::append(const _Tp & __t, size_type __pos, size_type __n)
2290{
2291    __self_view __sv = __t;
2292    size_type __sz = __sv.size();
2293    if (__pos > __sz)
2294        this->__throw_out_of_range();
2295    return append(__sv.data() + __pos, _VSTD::min(__n, __sz - __pos));
2296}
2297
2298template <class _CharT, class _Traits, class _Allocator>
2299basic_string<_CharT, _Traits, _Allocator>&
2300basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s)
2301{
2302    _LIBCPP_ASSERT(__s != nullptr, "string::append received nullptr");
2303    return append(__s, traits_type::length(__s));
2304}
2305
2306// insert
2307
2308template <class _CharT, class _Traits, class _Allocator>
2309basic_string<_CharT, _Traits, _Allocator>&
2310basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s, size_type __n)
2311{
2312    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::insert received nullptr");
2313    size_type __sz = size();
2314    if (__pos > __sz)
2315        this->__throw_out_of_range();
2316    size_type __cap = capacity();
2317    if (__cap - __sz >= __n)
2318    {
2319        if (__n)
2320        {
2321            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2322            size_type __n_move = __sz - __pos;
2323            if (__n_move != 0)
2324            {
2325                if (__p + __pos <= __s && __s < __p + __sz)
2326                    __s += __n;
2327                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2328            }
2329            traits_type::move(__p + __pos, __s, __n);
2330            __sz += __n;
2331            __set_size(__sz);
2332            traits_type::assign(__p[__sz], value_type());
2333        }
2334    }
2335    else
2336        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __pos, 0, __n, __s);
2337    return *this;
2338}
2339
2340template <class _CharT, class _Traits, class _Allocator>
2341basic_string<_CharT, _Traits, _Allocator>&
2342basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n, value_type __c)
2343{
2344    size_type __sz = size();
2345    if (__pos > __sz)
2346        this->__throw_out_of_range();
2347    if (__n)
2348    {
2349        size_type __cap = capacity();
2350        value_type* __p;
2351        if (__cap - __sz >= __n)
2352        {
2353            __p = _VSTD::__to_raw_pointer(__get_pointer());
2354            size_type __n_move = __sz - __pos;
2355            if (__n_move != 0)
2356                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2357        }
2358        else
2359        {
2360            __grow_by(__cap, __sz + __n - __cap, __sz, __pos, 0, __n);
2361            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2362        }
2363        traits_type::assign(__p + __pos, __n, __c);
2364        __sz += __n;
2365        __set_size(__sz);
2366        traits_type::assign(__p[__sz], value_type());
2367    }
2368    return *this;
2369}
2370
2371template <class _CharT, class _Traits, class _Allocator>
2372template<class _InputIterator>
2373typename enable_if
2374<
2375   __is_exactly_input_iterator<_InputIterator>::value
2376        || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
2377   typename basic_string<_CharT, _Traits, _Allocator>::iterator
2378>::type
2379basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _InputIterator __first, _InputIterator __last)
2380{
2381#if _LIBCPP_DEBUG_LEVEL >= 2
2382    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2383        "string::insert(iterator, range) called with an iterator not"
2384        " referring to this string");
2385#endif
2386    const basic_string __temp(__first, __last, __alloc());
2387    return insert(__pos, __temp.data(), __temp.data() + __temp.size());
2388}
2389
2390template <class _CharT, class _Traits, class _Allocator>
2391template<class _ForwardIterator>
2392typename enable_if
2393<
2394    __is_forward_iterator<_ForwardIterator>::value
2395        && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
2396    typename basic_string<_CharT, _Traits, _Allocator>::iterator
2397>::type
2398basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last)
2399{
2400#if _LIBCPP_DEBUG_LEVEL >= 2
2401    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2402        "string::insert(iterator, range) called with an iterator not"
2403        " referring to this string");
2404#endif
2405    size_type __ip = static_cast<size_type>(__pos - begin());
2406    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2407    if (__n)
2408    {
2409        if ( __ptr_in_range(&*__first, data(), data() + size()))
2410        {
2411            const basic_string __temp(__first, __last, __alloc());
2412            return insert(__pos, __temp.data(), __temp.data() + __temp.size());
2413        }
2414
2415        size_type __sz = size();
2416        size_type __cap = capacity();
2417        value_type* __p;
2418        if (__cap - __sz >= __n)
2419        {
2420            __p = _VSTD::__to_raw_pointer(__get_pointer());
2421            size_type __n_move = __sz - __ip;
2422            if (__n_move != 0)
2423                traits_type::move(__p + __ip + __n, __p + __ip, __n_move);
2424        }
2425        else
2426        {
2427            __grow_by(__cap, __sz + __n - __cap, __sz, __ip, 0, __n);
2428            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2429        }
2430        __sz += __n;
2431        __set_size(__sz);
2432        traits_type::assign(__p[__sz], value_type());
2433        for (__p += __ip; __first != __last; ++__p, ++__first)
2434            traits_type::assign(*__p, *__first);
2435    }
2436    return begin() + __ip;
2437}
2438
2439template <class _CharT, class _Traits, class _Allocator>
2440inline _LIBCPP_INLINE_VISIBILITY
2441basic_string<_CharT, _Traits, _Allocator>&
2442basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str)
2443{
2444    return insert(__pos1, __str.data(), __str.size());
2445}
2446
2447template <class _CharT, class _Traits, class _Allocator>
2448basic_string<_CharT, _Traits, _Allocator>&
2449basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str,
2450                                                  size_type __pos2, size_type __n)
2451{
2452    size_type __str_sz = __str.size();
2453    if (__pos2 > __str_sz)
2454        this->__throw_out_of_range();
2455    return insert(__pos1, __str.data() + __pos2, _VSTD::min(__n, __str_sz - __pos2));
2456}
2457
2458template <class _CharT, class _Traits, class _Allocator>
2459template <class _Tp>
2460typename enable_if
2461<
2462    __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2463	basic_string<_CharT, _Traits, _Allocator>&
2464>::type
2465basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const _Tp& __t,
2466                                                  size_type __pos2, size_type __n)
2467{
2468    __self_view __sv = __t;
2469    size_type __str_sz = __sv.size();
2470    if (__pos2 > __str_sz)
2471        this->__throw_out_of_range();
2472    return insert(__pos1, __sv.data() + __pos2, _VSTD::min(__n, __str_sz - __pos2));
2473}
2474
2475template <class _CharT, class _Traits, class _Allocator>
2476basic_string<_CharT, _Traits, _Allocator>&
2477basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s)
2478{
2479    _LIBCPP_ASSERT(__s != nullptr, "string::insert received nullptr");
2480    return insert(__pos, __s, traits_type::length(__s));
2481}
2482
2483template <class _CharT, class _Traits, class _Allocator>
2484typename basic_string<_CharT, _Traits, _Allocator>::iterator
2485basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_type __c)
2486{
2487    size_type __ip = static_cast<size_type>(__pos - begin());
2488    size_type __sz = size();
2489    size_type __cap = capacity();
2490    value_type* __p;
2491    if (__cap == __sz)
2492    {
2493        __grow_by(__cap, 1, __sz, __ip, 0, 1);
2494        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2495    }
2496    else
2497    {
2498        __p = _VSTD::__to_raw_pointer(__get_pointer());
2499        size_type __n_move = __sz - __ip;
2500        if (__n_move != 0)
2501            traits_type::move(__p + __ip + 1, __p + __ip, __n_move);
2502    }
2503    traits_type::assign(__p[__ip], __c);
2504    traits_type::assign(__p[++__sz], value_type());
2505    __set_size(__sz);
2506    return begin() + static_cast<difference_type>(__ip);
2507}
2508
2509template <class _CharT, class _Traits, class _Allocator>
2510inline _LIBCPP_INLINE_VISIBILITY
2511typename basic_string<_CharT, _Traits, _Allocator>::iterator
2512basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, size_type __n, value_type __c)
2513{
2514#if _LIBCPP_DEBUG_LEVEL >= 2
2515    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2516        "string::insert(iterator, n, value) called with an iterator not"
2517        " referring to this string");
2518#endif
2519    difference_type __p = __pos - begin();
2520    insert(static_cast<size_type>(__p), __n, __c);
2521    return begin() + __p;
2522}
2523
2524// replace
2525
2526template <class _CharT, class _Traits, class _Allocator>
2527basic_string<_CharT, _Traits, _Allocator>&
2528basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2)
2529{
2530    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::replace received nullptr");
2531    size_type __sz = size();
2532    if (__pos > __sz)
2533        this->__throw_out_of_range();
2534    __n1 = _VSTD::min(__n1, __sz - __pos);
2535    size_type __cap = capacity();
2536    if (__cap - __sz + __n1 >= __n2)
2537    {
2538        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2539        if (__n1 != __n2)
2540        {
2541            size_type __n_move = __sz - __pos - __n1;
2542            if (__n_move != 0)
2543            {
2544                if (__n1 > __n2)
2545                {
2546                    traits_type::move(__p + __pos, __s, __n2);
2547                    traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2548                    goto __finish;
2549                }
2550                if (__p + __pos < __s && __s < __p + __sz)
2551                {
2552                    if (__p + __pos + __n1 <= __s)
2553                        __s += __n2 - __n1;
2554                    else // __p + __pos < __s < __p + __pos + __n1
2555                    {
2556                        traits_type::move(__p + __pos, __s, __n1);
2557                        __pos += __n1;
2558                        __s += __n2;
2559                        __n2 -= __n1;
2560                        __n1 = 0;
2561                    }
2562                }
2563                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2564            }
2565        }
2566        traits_type::move(__p + __pos, __s, __n2);
2567__finish:
2568        __sz += __n2 - __n1;
2569        __set_size(__sz);
2570        __invalidate_iterators_past(__sz);
2571        traits_type::assign(__p[__sz], value_type());
2572    }
2573    else
2574        __grow_by_and_replace(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2, __s);
2575    return *this;
2576}
2577
2578template <class _CharT, class _Traits, class _Allocator>
2579basic_string<_CharT, _Traits, _Allocator>&
2580basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, size_type __n2, value_type __c)
2581{
2582    size_type __sz = size();
2583    if (__pos > __sz)
2584        this->__throw_out_of_range();
2585    __n1 = _VSTD::min(__n1, __sz - __pos);
2586    size_type __cap = capacity();
2587    value_type* __p;
2588    if (__cap - __sz + __n1 >= __n2)
2589    {
2590        __p = _VSTD::__to_raw_pointer(__get_pointer());
2591        if (__n1 != __n2)
2592        {
2593            size_type __n_move = __sz - __pos - __n1;
2594            if (__n_move != 0)
2595                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2596        }
2597    }
2598    else
2599    {
2600        __grow_by(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2);
2601        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2602    }
2603    traits_type::assign(__p + __pos, __n2, __c);
2604    __sz += __n2 - __n1;
2605    __set_size(__sz);
2606    __invalidate_iterators_past(__sz);
2607    traits_type::assign(__p[__sz], value_type());
2608    return *this;
2609}
2610
2611template <class _CharT, class _Traits, class _Allocator>
2612template<class _InputIterator>
2613typename enable_if
2614<
2615    __is_input_iterator<_InputIterator>::value,
2616    basic_string<_CharT, _Traits, _Allocator>&
2617>::type
2618basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2,
2619                                                   _InputIterator __j1, _InputIterator __j2)
2620{
2621    const basic_string __temp(__j1, __j2, __alloc());
2622    return this->replace(__i1, __i2, __temp);
2623}
2624
2625template <class _CharT, class _Traits, class _Allocator>
2626inline _LIBCPP_INLINE_VISIBILITY
2627basic_string<_CharT, _Traits, _Allocator>&
2628basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str)
2629{
2630    return replace(__pos1, __n1, __str.data(), __str.size());
2631}
2632
2633template <class _CharT, class _Traits, class _Allocator>
2634basic_string<_CharT, _Traits, _Allocator>&
2635basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str,
2636                                                   size_type __pos2, size_type __n2)
2637{
2638    size_type __str_sz = __str.size();
2639    if (__pos2 > __str_sz)
2640        this->__throw_out_of_range();
2641    return replace(__pos1, __n1, __str.data() + __pos2, _VSTD::min(__n2, __str_sz - __pos2));
2642}
2643
2644template <class _CharT, class _Traits, class _Allocator>
2645template <class _Tp>
2646typename enable_if
2647<
2648	__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2649	basic_string<_CharT, _Traits, _Allocator>&
2650>::type
2651basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const _Tp& __t,
2652                                                   size_type __pos2, size_type __n2)
2653{
2654    __self_view __sv = __t;
2655    size_type __str_sz = __sv.size();
2656    if (__pos2 > __str_sz)
2657        this->__throw_out_of_range();
2658    return replace(__pos1, __n1, __sv.data() + __pos2, _VSTD::min(__n2, __str_sz - __pos2));
2659}
2660
2661template <class _CharT, class _Traits, class _Allocator>
2662basic_string<_CharT, _Traits, _Allocator>&
2663basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s)
2664{
2665    _LIBCPP_ASSERT(__s != nullptr, "string::replace received nullptr");
2666    return replace(__pos, __n1, __s, traits_type::length(__s));
2667}
2668
2669template <class _CharT, class _Traits, class _Allocator>
2670inline _LIBCPP_INLINE_VISIBILITY
2671basic_string<_CharT, _Traits, _Allocator>&
2672basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const basic_string& __str)
2673{
2674    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1),
2675                   __str.data(), __str.size());
2676}
2677
2678template <class _CharT, class _Traits, class _Allocator>
2679inline _LIBCPP_INLINE_VISIBILITY
2680basic_string<_CharT, _Traits, _Allocator>&
2681basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n)
2682{
2683    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s, __n);
2684}
2685
2686template <class _CharT, class _Traits, class _Allocator>
2687inline _LIBCPP_INLINE_VISIBILITY
2688basic_string<_CharT, _Traits, _Allocator>&
2689basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s)
2690{
2691    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s);
2692}
2693
2694template <class _CharT, class _Traits, class _Allocator>
2695inline _LIBCPP_INLINE_VISIBILITY
2696basic_string<_CharT, _Traits, _Allocator>&
2697basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c)
2698{
2699    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __n, __c);
2700}
2701
2702// erase
2703
2704template <class _CharT, class _Traits, class _Allocator>
2705basic_string<_CharT, _Traits, _Allocator>&
2706basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos, size_type __n)
2707{
2708    size_type __sz = size();
2709    if (__pos > __sz)
2710        this->__throw_out_of_range();
2711    if (__n)
2712    {
2713        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2714        __n = _VSTD::min(__n, __sz - __pos);
2715        size_type __n_move = __sz - __pos - __n;
2716        if (__n_move != 0)
2717            traits_type::move(__p + __pos, __p + __pos + __n, __n_move);
2718        __sz -= __n;
2719        __set_size(__sz);
2720        __invalidate_iterators_past(__sz);
2721        traits_type::assign(__p[__sz], value_type());
2722    }
2723    return *this;
2724}
2725
2726template <class _CharT, class _Traits, class _Allocator>
2727inline _LIBCPP_INLINE_VISIBILITY
2728typename basic_string<_CharT, _Traits, _Allocator>::iterator
2729basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __pos)
2730{
2731#if _LIBCPP_DEBUG_LEVEL >= 2
2732    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2733        "string::erase(iterator) called with an iterator not"
2734        " referring to this string");
2735#endif
2736    _LIBCPP_ASSERT(__pos != end(),
2737        "string::erase(iterator) called with a non-dereferenceable iterator");
2738    iterator __b = begin();
2739    size_type __r = static_cast<size_type>(__pos - __b);
2740    erase(__r, 1);
2741    return __b + static_cast<difference_type>(__r);
2742}
2743
2744template <class _CharT, class _Traits, class _Allocator>
2745inline _LIBCPP_INLINE_VISIBILITY
2746typename basic_string<_CharT, _Traits, _Allocator>::iterator
2747basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __first, const_iterator __last)
2748{
2749#if _LIBCPP_DEBUG_LEVEL >= 2
2750    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
2751        "string::erase(iterator,  iterator) called with an iterator not"
2752        " referring to this string");
2753#endif
2754    _LIBCPP_ASSERT(__first <= __last, "string::erase(first, last) called with invalid range");
2755    iterator __b = begin();
2756    size_type __r = static_cast<size_type>(__first - __b);
2757    erase(__r, static_cast<size_type>(__last - __first));
2758    return __b + static_cast<difference_type>(__r);
2759}
2760
2761template <class _CharT, class _Traits, class _Allocator>
2762inline _LIBCPP_INLINE_VISIBILITY
2763void
2764basic_string<_CharT, _Traits, _Allocator>::pop_back()
2765{
2766    _LIBCPP_ASSERT(!empty(), "string::pop_back(): string is already empty");
2767    size_type __sz;
2768    if (__is_long())
2769    {
2770        __sz = __get_long_size() - 1;
2771        __set_long_size(__sz);
2772        traits_type::assign(*(__get_long_pointer() + __sz), value_type());
2773    }
2774    else
2775    {
2776        __sz = __get_short_size() - 1;
2777        __set_short_size(__sz);
2778        traits_type::assign(*(__get_short_pointer() + __sz), value_type());
2779    }
2780    __invalidate_iterators_past(__sz);
2781}
2782
2783template <class _CharT, class _Traits, class _Allocator>
2784inline _LIBCPP_INLINE_VISIBILITY
2785void
2786basic_string<_CharT, _Traits, _Allocator>::clear() _NOEXCEPT
2787{
2788    __invalidate_all_iterators();
2789    if (__is_long())
2790    {
2791        traits_type::assign(*__get_long_pointer(), value_type());
2792        __set_long_size(0);
2793    }
2794    else
2795    {
2796        traits_type::assign(*__get_short_pointer(), value_type());
2797        __set_short_size(0);
2798    }
2799}
2800
2801template <class _CharT, class _Traits, class _Allocator>
2802inline _LIBCPP_INLINE_VISIBILITY
2803void
2804basic_string<_CharT, _Traits, _Allocator>::__erase_to_end(size_type __pos)
2805{
2806    if (__is_long())
2807    {
2808        traits_type::assign(*(__get_long_pointer() + __pos), value_type());
2809        __set_long_size(__pos);
2810    }
2811    else
2812    {
2813        traits_type::assign(*(__get_short_pointer() + __pos), value_type());
2814        __set_short_size(__pos);
2815    }
2816    __invalidate_iterators_past(__pos);
2817}
2818
2819template <class _CharT, class _Traits, class _Allocator>
2820void
2821basic_string<_CharT, _Traits, _Allocator>::resize(size_type __n, value_type __c)
2822{
2823    size_type __sz = size();
2824    if (__n > __sz)
2825        append(__n - __sz, __c);
2826    else
2827        __erase_to_end(__n);
2828}
2829
2830template <class _CharT, class _Traits, class _Allocator>
2831inline _LIBCPP_INLINE_VISIBILITY
2832typename basic_string<_CharT, _Traits, _Allocator>::size_type
2833basic_string<_CharT, _Traits, _Allocator>::max_size() const _NOEXCEPT
2834{
2835    size_type __m = __alloc_traits::max_size(__alloc());
2836#if _LIBCPP_BIG_ENDIAN
2837    return (__m <= ~__long_mask ? __m : __m/2) - __alignment;
2838#else
2839    return __m - __alignment;
2840#endif
2841}
2842
2843template <class _CharT, class _Traits, class _Allocator>
2844void
2845basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __res_arg)
2846{
2847    if (__res_arg > max_size())
2848        this->__throw_length_error();
2849    size_type __cap = capacity();
2850    size_type __sz = size();
2851    __res_arg = _VSTD::max(__res_arg, __sz);
2852    __res_arg = __recommend(__res_arg);
2853    if (__res_arg != __cap)
2854    {
2855        pointer __new_data, __p;
2856        bool __was_long, __now_long;
2857        if (__res_arg == __min_cap - 1)
2858        {
2859            __was_long = true;
2860            __now_long = false;
2861            __new_data = __get_short_pointer();
2862            __p = __get_long_pointer();
2863        }
2864        else
2865        {
2866            if (__res_arg > __cap)
2867                __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
2868            else
2869            {
2870            #ifndef _LIBCPP_NO_EXCEPTIONS
2871                try
2872                {
2873            #endif  // _LIBCPP_NO_EXCEPTIONS
2874                    __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
2875            #ifndef _LIBCPP_NO_EXCEPTIONS
2876                }
2877                catch (...)
2878                {
2879                    return;
2880                }
2881            #else  // _LIBCPP_NO_EXCEPTIONS
2882                if (__new_data == nullptr)
2883                    return;
2884            #endif  // _LIBCPP_NO_EXCEPTIONS
2885            }
2886            __now_long = true;
2887            __was_long = __is_long();
2888            __p = __get_pointer();
2889        }
2890        traits_type::copy(_VSTD::__to_raw_pointer(__new_data),
2891                          _VSTD::__to_raw_pointer(__p), size()+1);
2892        if (__was_long)
2893            __alloc_traits::deallocate(__alloc(), __p, __cap+1);
2894        if (__now_long)
2895        {
2896            __set_long_cap(__res_arg+1);
2897            __set_long_size(__sz);
2898            __set_long_pointer(__new_data);
2899        }
2900        else
2901            __set_short_size(__sz);
2902        __invalidate_all_iterators();
2903    }
2904}
2905
2906template <class _CharT, class _Traits, class _Allocator>
2907inline _LIBCPP_INLINE_VISIBILITY
2908typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2909basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos) const _NOEXCEPT
2910{
2911    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
2912    return *(data() + __pos);
2913}
2914
2915template <class _CharT, class _Traits, class _Allocator>
2916inline _LIBCPP_INLINE_VISIBILITY
2917typename basic_string<_CharT, _Traits, _Allocator>::reference
2918basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos) _NOEXCEPT
2919{
2920    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
2921    return *(__get_pointer() + __pos);
2922}
2923
2924template <class _CharT, class _Traits, class _Allocator>
2925typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2926basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) const
2927{
2928    if (__n >= size())
2929        this->__throw_out_of_range();
2930    return (*this)[__n];
2931}
2932
2933template <class _CharT, class _Traits, class _Allocator>
2934typename basic_string<_CharT, _Traits, _Allocator>::reference
2935basic_string<_CharT, _Traits, _Allocator>::at(size_type __n)
2936{
2937    if (__n >= size())
2938        this->__throw_out_of_range();
2939    return (*this)[__n];
2940}
2941
2942template <class _CharT, class _Traits, class _Allocator>
2943inline _LIBCPP_INLINE_VISIBILITY
2944typename basic_string<_CharT, _Traits, _Allocator>::reference
2945basic_string<_CharT, _Traits, _Allocator>::front()
2946{
2947    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
2948    return *__get_pointer();
2949}
2950
2951template <class _CharT, class _Traits, class _Allocator>
2952inline _LIBCPP_INLINE_VISIBILITY
2953typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2954basic_string<_CharT, _Traits, _Allocator>::front() const
2955{
2956    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
2957    return *data();
2958}
2959
2960template <class _CharT, class _Traits, class _Allocator>
2961inline _LIBCPP_INLINE_VISIBILITY
2962typename basic_string<_CharT, _Traits, _Allocator>::reference
2963basic_string<_CharT, _Traits, _Allocator>::back()
2964{
2965    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
2966    return *(__get_pointer() + size() - 1);
2967}
2968
2969template <class _CharT, class _Traits, class _Allocator>
2970inline _LIBCPP_INLINE_VISIBILITY
2971typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2972basic_string<_CharT, _Traits, _Allocator>::back() const
2973{
2974    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
2975    return *(data() + size() - 1);
2976}
2977
2978template <class _CharT, class _Traits, class _Allocator>
2979typename basic_string<_CharT, _Traits, _Allocator>::size_type
2980basic_string<_CharT, _Traits, _Allocator>::copy(value_type* __s, size_type __n, size_type __pos) const
2981{
2982    size_type __sz = size();
2983    if (__pos > __sz)
2984        this->__throw_out_of_range();
2985    size_type __rlen = _VSTD::min(__n, __sz - __pos);
2986    traits_type::copy(__s, data() + __pos, __rlen);
2987    return __rlen;
2988}
2989
2990template <class _CharT, class _Traits, class _Allocator>
2991inline _LIBCPP_INLINE_VISIBILITY
2992basic_string<_CharT, _Traits, _Allocator>
2993basic_string<_CharT, _Traits, _Allocator>::substr(size_type __pos, size_type __n) const
2994{
2995    return basic_string(*this, __pos, __n, __alloc());
2996}
2997
2998template <class _CharT, class _Traits, class _Allocator>
2999inline _LIBCPP_INLINE_VISIBILITY
3000void
3001basic_string<_CharT, _Traits, _Allocator>::swap(basic_string& __str)
3002#if _LIBCPP_STD_VER >= 14
3003        _NOEXCEPT_DEBUG
3004#else
3005        _NOEXCEPT_DEBUG_(!__alloc_traits::propagate_on_container_swap::value ||
3006                    __is_nothrow_swappable<allocator_type>::value)
3007#endif
3008{
3009#if _LIBCPP_DEBUG_LEVEL >= 2
3010    if (!__is_long())
3011        __get_db()->__invalidate_all(this);
3012    if (!__str.__is_long())
3013        __get_db()->__invalidate_all(&__str);
3014    __get_db()->swap(this, &__str);
3015#endif
3016    _LIBCPP_ASSERT(
3017        __alloc_traits::propagate_on_container_swap::value ||
3018        __alloc_traits::is_always_equal::value ||
3019        __alloc() == __str.__alloc(), "swapping non-equal allocators");
3020    _VSTD::swap(__r_.first(), __str.__r_.first());
3021    __swap_allocator(__alloc(), __str.__alloc());
3022}
3023
3024// find
3025
3026template <class _Traits>
3027struct _LIBCPP_HIDDEN __traits_eq
3028{
3029    typedef typename _Traits::char_type char_type;
3030    _LIBCPP_INLINE_VISIBILITY
3031    bool operator()(const char_type& __x, const char_type& __y) _NOEXCEPT
3032        {return _Traits::eq(__x, __y);}
3033};
3034
3035template<class _CharT, class _Traits, class _Allocator>
3036typename basic_string<_CharT, _Traits, _Allocator>::size_type
3037basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3038                                                size_type __pos,
3039                                                size_type __n) const _NOEXCEPT
3040{
3041    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find(): received nullptr");
3042    return __str_find<value_type, size_type, traits_type, npos>
3043        (data(), size(), __s, __pos, __n);
3044}
3045
3046template<class _CharT, class _Traits, class _Allocator>
3047inline _LIBCPP_INLINE_VISIBILITY
3048typename basic_string<_CharT, _Traits, _Allocator>::size_type
3049basic_string<_CharT, _Traits, _Allocator>::find(const basic_string& __str,
3050                                                size_type __pos) const _NOEXCEPT
3051{
3052    return __str_find<value_type, size_type, traits_type, npos>
3053        (data(), size(), __str.data(), __pos, __str.size());
3054}
3055
3056template<class _CharT, class _Traits, class _Allocator>
3057inline _LIBCPP_INLINE_VISIBILITY
3058typename basic_string<_CharT, _Traits, _Allocator>::size_type
3059basic_string<_CharT, _Traits, _Allocator>::find(__self_view __sv,
3060                                                size_type __pos) const _NOEXCEPT
3061{
3062    return __str_find<value_type, size_type, traits_type, npos>
3063        (data(), size(), __sv.data(), __pos, __sv.size());
3064}
3065
3066template<class _CharT, class _Traits, class _Allocator>
3067inline _LIBCPP_INLINE_VISIBILITY
3068typename basic_string<_CharT, _Traits, _Allocator>::size_type
3069basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3070                                                size_type __pos) const _NOEXCEPT
3071{
3072    _LIBCPP_ASSERT(__s != nullptr, "string::find(): received nullptr");
3073    return __str_find<value_type, size_type, traits_type, npos>
3074        (data(), size(), __s, __pos, traits_type::length(__s));
3075}
3076
3077template<class _CharT, class _Traits, class _Allocator>
3078typename basic_string<_CharT, _Traits, _Allocator>::size_type
3079basic_string<_CharT, _Traits, _Allocator>::find(value_type __c,
3080                                                size_type __pos) const _NOEXCEPT
3081{
3082    return __str_find<value_type, size_type, traits_type, npos>
3083        (data(), size(), __c, __pos);
3084}
3085
3086// rfind
3087
3088template<class _CharT, class _Traits, class _Allocator>
3089typename basic_string<_CharT, _Traits, _Allocator>::size_type
3090basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3091                                                 size_type __pos,
3092                                                 size_type __n) const _NOEXCEPT
3093{
3094    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::rfind(): received nullptr");
3095    return __str_rfind<value_type, size_type, traits_type, npos>
3096        (data(), size(), __s, __pos, __n);
3097}
3098
3099template<class _CharT, class _Traits, class _Allocator>
3100inline _LIBCPP_INLINE_VISIBILITY
3101typename basic_string<_CharT, _Traits, _Allocator>::size_type
3102basic_string<_CharT, _Traits, _Allocator>::rfind(const basic_string& __str,
3103                                                 size_type __pos) const _NOEXCEPT
3104{
3105    return __str_rfind<value_type, size_type, traits_type, npos>
3106        (data(), size(), __str.data(), __pos, __str.size());
3107}
3108
3109template<class _CharT, class _Traits, class _Allocator>
3110inline _LIBCPP_INLINE_VISIBILITY
3111typename basic_string<_CharT, _Traits, _Allocator>::size_type
3112basic_string<_CharT, _Traits, _Allocator>::rfind(__self_view __sv,
3113                                                size_type __pos) const _NOEXCEPT
3114{
3115    return __str_rfind<value_type, size_type, traits_type, npos>
3116        (data(), size(), __sv.data(), __pos, __sv.size());
3117}
3118
3119template<class _CharT, class _Traits, class _Allocator>
3120inline _LIBCPP_INLINE_VISIBILITY
3121typename basic_string<_CharT, _Traits, _Allocator>::size_type
3122basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3123                                                 size_type __pos) const _NOEXCEPT
3124{
3125    _LIBCPP_ASSERT(__s != nullptr, "string::rfind(): received nullptr");
3126    return __str_rfind<value_type, size_type, traits_type, npos>
3127        (data(), size(), __s, __pos, traits_type::length(__s));
3128}
3129
3130template<class _CharT, class _Traits, class _Allocator>
3131typename basic_string<_CharT, _Traits, _Allocator>::size_type
3132basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c,
3133                                                 size_type __pos) const _NOEXCEPT
3134{
3135    return __str_rfind<value_type, size_type, traits_type, npos>
3136        (data(), size(), __c, __pos);
3137}
3138
3139// find_first_of
3140
3141template<class _CharT, class _Traits, class _Allocator>
3142typename basic_string<_CharT, _Traits, _Allocator>::size_type
3143basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3144                                                         size_type __pos,
3145                                                         size_type __n) const _NOEXCEPT
3146{
3147    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_of(): received nullptr");
3148    return __str_find_first_of<value_type, size_type, traits_type, npos>
3149        (data(), size(), __s, __pos, __n);
3150}
3151
3152template<class _CharT, class _Traits, class _Allocator>
3153inline _LIBCPP_INLINE_VISIBILITY
3154typename basic_string<_CharT, _Traits, _Allocator>::size_type
3155basic_string<_CharT, _Traits, _Allocator>::find_first_of(const basic_string& __str,
3156                                                         size_type __pos) const _NOEXCEPT
3157{
3158    return __str_find_first_of<value_type, size_type, traits_type, npos>
3159        (data(), size(), __str.data(), __pos, __str.size());
3160}
3161
3162template<class _CharT, class _Traits, class _Allocator>
3163inline _LIBCPP_INLINE_VISIBILITY
3164typename basic_string<_CharT, _Traits, _Allocator>::size_type
3165basic_string<_CharT, _Traits, _Allocator>::find_first_of(__self_view __sv,
3166                                                size_type __pos) const _NOEXCEPT
3167{
3168    return __str_find_first_of<value_type, size_type, traits_type, npos>
3169        (data(), size(), __sv.data(), __pos, __sv.size());
3170}
3171
3172template<class _CharT, class _Traits, class _Allocator>
3173inline _LIBCPP_INLINE_VISIBILITY
3174typename basic_string<_CharT, _Traits, _Allocator>::size_type
3175basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3176                                                         size_type __pos) const _NOEXCEPT
3177{
3178    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_of(): received nullptr");
3179    return __str_find_first_of<value_type, size_type, traits_type, npos>
3180        (data(), size(), __s, __pos, traits_type::length(__s));
3181}
3182
3183template<class _CharT, class _Traits, class _Allocator>
3184inline _LIBCPP_INLINE_VISIBILITY
3185typename basic_string<_CharT, _Traits, _Allocator>::size_type
3186basic_string<_CharT, _Traits, _Allocator>::find_first_of(value_type __c,
3187                                                         size_type __pos) const _NOEXCEPT
3188{
3189    return find(__c, __pos);
3190}
3191
3192// find_last_of
3193
3194template<class _CharT, class _Traits, class _Allocator>
3195typename basic_string<_CharT, _Traits, _Allocator>::size_type
3196basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3197                                                        size_type __pos,
3198                                                        size_type __n) const _NOEXCEPT
3199{
3200    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_of(): received nullptr");
3201    return __str_find_last_of<value_type, size_type, traits_type, npos>
3202        (data(), size(), __s, __pos, __n);
3203}
3204
3205template<class _CharT, class _Traits, class _Allocator>
3206inline _LIBCPP_INLINE_VISIBILITY
3207typename basic_string<_CharT, _Traits, _Allocator>::size_type
3208basic_string<_CharT, _Traits, _Allocator>::find_last_of(const basic_string& __str,
3209                                                        size_type __pos) const _NOEXCEPT
3210{
3211    return __str_find_last_of<value_type, size_type, traits_type, npos>
3212        (data(), size(), __str.data(), __pos, __str.size());
3213}
3214
3215template<class _CharT, class _Traits, class _Allocator>
3216inline _LIBCPP_INLINE_VISIBILITY
3217typename basic_string<_CharT, _Traits, _Allocator>::size_type
3218basic_string<_CharT, _Traits, _Allocator>::find_last_of(__self_view __sv,
3219                                                size_type __pos) const _NOEXCEPT
3220{
3221    return __str_find_last_of<value_type, size_type, traits_type, npos>
3222        (data(), size(), __sv.data(), __pos, __sv.size());
3223}
3224
3225template<class _CharT, class _Traits, class _Allocator>
3226inline _LIBCPP_INLINE_VISIBILITY
3227typename basic_string<_CharT, _Traits, _Allocator>::size_type
3228basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3229                                                        size_type __pos) const _NOEXCEPT
3230{
3231    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_of(): received nullptr");
3232    return __str_find_last_of<value_type, size_type, traits_type, npos>
3233        (data(), size(), __s, __pos, traits_type::length(__s));
3234}
3235
3236template<class _CharT, class _Traits, class _Allocator>
3237inline _LIBCPP_INLINE_VISIBILITY
3238typename basic_string<_CharT, _Traits, _Allocator>::size_type
3239basic_string<_CharT, _Traits, _Allocator>::find_last_of(value_type __c,
3240                                                        size_type __pos) const _NOEXCEPT
3241{
3242    return rfind(__c, __pos);
3243}
3244
3245// find_first_not_of
3246
3247template<class _CharT, class _Traits, class _Allocator>
3248typename basic_string<_CharT, _Traits, _Allocator>::size_type
3249basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3250                                                             size_type __pos,
3251                                                             size_type __n) const _NOEXCEPT
3252{
3253    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_not_of(): received nullptr");
3254    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3255        (data(), size(), __s, __pos, __n);
3256}
3257
3258template<class _CharT, class _Traits, class _Allocator>
3259inline _LIBCPP_INLINE_VISIBILITY
3260typename basic_string<_CharT, _Traits, _Allocator>::size_type
3261basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const basic_string& __str,
3262                                                             size_type __pos) const _NOEXCEPT
3263{
3264    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3265        (data(), size(), __str.data(), __pos, __str.size());
3266}
3267
3268template<class _CharT, class _Traits, class _Allocator>
3269inline _LIBCPP_INLINE_VISIBILITY
3270typename basic_string<_CharT, _Traits, _Allocator>::size_type
3271basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(__self_view __sv,
3272                                                size_type __pos) const _NOEXCEPT
3273{
3274    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3275        (data(), size(), __sv.data(), __pos, __sv.size());
3276}
3277
3278template<class _CharT, class _Traits, class _Allocator>
3279inline _LIBCPP_INLINE_VISIBILITY
3280typename basic_string<_CharT, _Traits, _Allocator>::size_type
3281basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3282                                                             size_type __pos) const _NOEXCEPT
3283{
3284    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_not_of(): received nullptr");
3285    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3286        (data(), size(), __s, __pos, traits_type::length(__s));
3287}
3288
3289template<class _CharT, class _Traits, class _Allocator>
3290inline _LIBCPP_INLINE_VISIBILITY
3291typename basic_string<_CharT, _Traits, _Allocator>::size_type
3292basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c,
3293                                                             size_type __pos) const _NOEXCEPT
3294{
3295    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3296        (data(), size(), __c, __pos);
3297}
3298
3299// find_last_not_of
3300
3301template<class _CharT, class _Traits, class _Allocator>
3302typename basic_string<_CharT, _Traits, _Allocator>::size_type
3303basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3304                                                            size_type __pos,
3305                                                            size_type __n) const _NOEXCEPT
3306{
3307    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_not_of(): received nullptr");
3308    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3309        (data(), size(), __s, __pos, __n);
3310}
3311
3312template<class _CharT, class _Traits, class _Allocator>
3313inline _LIBCPP_INLINE_VISIBILITY
3314typename basic_string<_CharT, _Traits, _Allocator>::size_type
3315basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const basic_string& __str,
3316                                                            size_type __pos) const _NOEXCEPT
3317{
3318    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3319        (data(), size(), __str.data(), __pos, __str.size());
3320}
3321
3322template<class _CharT, class _Traits, class _Allocator>
3323inline _LIBCPP_INLINE_VISIBILITY
3324typename basic_string<_CharT, _Traits, _Allocator>::size_type
3325basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(__self_view __sv,
3326                                                size_type __pos) const _NOEXCEPT
3327{
3328    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3329        (data(), size(), __sv.data(), __pos, __sv.size());
3330}
3331
3332template<class _CharT, class _Traits, class _Allocator>
3333inline _LIBCPP_INLINE_VISIBILITY
3334typename basic_string<_CharT, _Traits, _Allocator>::size_type
3335basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3336                                                            size_type __pos) const _NOEXCEPT
3337{
3338    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_not_of(): received nullptr");
3339    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3340        (data(), size(), __s, __pos, traits_type::length(__s));
3341}
3342
3343template<class _CharT, class _Traits, class _Allocator>
3344inline _LIBCPP_INLINE_VISIBILITY
3345typename basic_string<_CharT, _Traits, _Allocator>::size_type
3346basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(value_type __c,
3347                                                            size_type __pos) const _NOEXCEPT
3348{
3349    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3350        (data(), size(), __c, __pos);
3351}
3352
3353// compare
3354
3355template <class _CharT, class _Traits, class _Allocator>
3356inline _LIBCPP_INLINE_VISIBILITY
3357int
3358basic_string<_CharT, _Traits, _Allocator>::compare(__self_view __sv) const _NOEXCEPT
3359{
3360    size_t __lhs_sz = size();
3361    size_t __rhs_sz = __sv.size();
3362    int __result = traits_type::compare(data(), __sv.data(),
3363                                        _VSTD::min(__lhs_sz, __rhs_sz));
3364    if (__result != 0)
3365        return __result;
3366    if (__lhs_sz < __rhs_sz)
3367        return -1;
3368    if (__lhs_sz > __rhs_sz)
3369        return 1;
3370    return 0;
3371}
3372
3373template <class _CharT, class _Traits, class _Allocator>
3374inline _LIBCPP_INLINE_VISIBILITY
3375int
3376basic_string<_CharT, _Traits, _Allocator>::compare(const basic_string& __str) const _NOEXCEPT
3377{
3378    return compare(__self_view(__str));
3379}
3380
3381template <class _CharT, class _Traits, class _Allocator>
3382int
3383basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3384                                                   size_type __n1,
3385                                                   const value_type* __s,
3386                                                   size_type __n2) const
3387{
3388    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::compare(): received nullptr");
3389    size_type __sz = size();
3390    if (__pos1 > __sz || __n2 == npos)
3391        this->__throw_out_of_range();
3392    size_type __rlen = _VSTD::min(__n1, __sz - __pos1);
3393    int __r = traits_type::compare(data() + __pos1, __s, _VSTD::min(__rlen, __n2));
3394    if (__r == 0)
3395    {
3396        if (__rlen < __n2)
3397            __r = -1;
3398        else if (__rlen > __n2)
3399            __r = 1;
3400    }
3401    return __r;
3402}
3403
3404template <class _CharT, class _Traits, class _Allocator>
3405inline _LIBCPP_INLINE_VISIBILITY
3406int
3407basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3408                                                   size_type __n1,
3409                                                   __self_view __sv) const
3410{
3411    return compare(__pos1, __n1, __sv.data(), __sv.size());
3412}
3413
3414template <class _CharT, class _Traits, class _Allocator>
3415inline _LIBCPP_INLINE_VISIBILITY
3416int
3417basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3418                                                   size_type __n1,
3419                                                   const basic_string& __str) const
3420{
3421    return compare(__pos1, __n1, __str.data(), __str.size());
3422}
3423
3424template <class _CharT, class _Traits, class _Allocator>
3425template <class _Tp>
3426typename enable_if
3427<
3428	__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
3429	int
3430>::type
3431basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3432                                                   size_type __n1,
3433                                                   const _Tp& __t,
3434                                                   size_type __pos2,
3435                                                   size_type __n2) const
3436{
3437    __self_view __sv = __t;
3438    return __self_view(*this).substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
3439}
3440
3441template <class _CharT, class _Traits, class _Allocator>
3442int
3443basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3444                                                   size_type __n1,
3445                                                   const basic_string& __str,
3446                                                   size_type __pos2,
3447                                                   size_type __n2) const
3448{
3449        return compare(__pos1, __n1, __self_view(__str), __pos2, __n2);
3450}
3451
3452template <class _CharT, class _Traits, class _Allocator>
3453int
3454basic_string<_CharT, _Traits, _Allocator>::compare(const value_type* __s) const _NOEXCEPT
3455{
3456    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3457    return compare(0, npos, __s, traits_type::length(__s));
3458}
3459
3460template <class _CharT, class _Traits, class _Allocator>
3461int
3462basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3463                                                   size_type __n1,
3464                                                   const value_type* __s) const
3465{
3466    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3467    return compare(__pos1, __n1, __s, traits_type::length(__s));
3468}
3469
3470// __invariants
3471
3472template<class _CharT, class _Traits, class _Allocator>
3473inline _LIBCPP_INLINE_VISIBILITY
3474bool
3475basic_string<_CharT, _Traits, _Allocator>::__invariants() const
3476{
3477    if (size() > capacity())
3478        return false;
3479    if (capacity() < __min_cap - 1)
3480        return false;
3481    if (data() == 0)
3482        return false;
3483    if (data()[size()] != value_type(0))
3484        return false;
3485    return true;
3486}
3487
3488// operator==
3489
3490template<class _CharT, class _Traits, class _Allocator>
3491inline _LIBCPP_INLINE_VISIBILITY
3492bool
3493operator==(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3494           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3495{
3496    size_t __lhs_sz = __lhs.size();
3497    return __lhs_sz == __rhs.size() && _Traits::compare(__lhs.data(),
3498                                                        __rhs.data(),
3499                                                        __lhs_sz) == 0;
3500}
3501
3502template<class _Allocator>
3503inline _LIBCPP_INLINE_VISIBILITY
3504bool
3505operator==(const basic_string<char, char_traits<char>, _Allocator>& __lhs,
3506           const basic_string<char, char_traits<char>, _Allocator>& __rhs) _NOEXCEPT
3507{
3508    size_t __lhs_sz = __lhs.size();
3509    if (__lhs_sz != __rhs.size())
3510        return false;
3511    const char* __lp = __lhs.data();
3512    const char* __rp = __rhs.data();
3513    if (__lhs.__is_long())
3514        return char_traits<char>::compare(__lp, __rp, __lhs_sz) == 0;
3515    for (; __lhs_sz != 0; --__lhs_sz, ++__lp, ++__rp)
3516        if (*__lp != *__rp)
3517            return false;
3518    return true;
3519}
3520
3521template<class _CharT, class _Traits, class _Allocator>
3522inline _LIBCPP_INLINE_VISIBILITY
3523bool
3524operator==(const _CharT* __lhs,
3525           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3526{
3527    typedef basic_string<_CharT, _Traits, _Allocator> _String;
3528    _LIBCPP_ASSERT(__lhs != nullptr, "operator==(char*, basic_string): received nullptr");
3529    size_t __lhs_len = _Traits::length(__lhs);
3530    if (__lhs_len != __rhs.size()) return false;
3531    return __rhs.compare(0, _String::npos, __lhs, __lhs_len) == 0;
3532}
3533
3534template<class _CharT, class _Traits, class _Allocator>
3535inline _LIBCPP_INLINE_VISIBILITY
3536bool
3537operator==(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3538           const _CharT* __rhs) _NOEXCEPT
3539{
3540    typedef basic_string<_CharT, _Traits, _Allocator> _String;
3541    _LIBCPP_ASSERT(__rhs != nullptr, "operator==(basic_string, char*): received nullptr");
3542    size_t __rhs_len = _Traits::length(__rhs);
3543    if (__rhs_len != __lhs.size()) return false;
3544    return __lhs.compare(0, _String::npos, __rhs, __rhs_len) == 0;
3545}
3546
3547template<class _CharT, class _Traits, class _Allocator>
3548inline _LIBCPP_INLINE_VISIBILITY
3549bool
3550operator!=(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3551           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3552{
3553    return !(__lhs == __rhs);
3554}
3555
3556template<class _CharT, class _Traits, class _Allocator>
3557inline _LIBCPP_INLINE_VISIBILITY
3558bool
3559operator!=(const _CharT* __lhs,
3560           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3561{
3562    return !(__lhs == __rhs);
3563}
3564
3565template<class _CharT, class _Traits, class _Allocator>
3566inline _LIBCPP_INLINE_VISIBILITY
3567bool
3568operator!=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3569           const _CharT* __rhs) _NOEXCEPT
3570{
3571    return !(__lhs == __rhs);
3572}
3573
3574// operator<
3575
3576template<class _CharT, class _Traits, class _Allocator>
3577inline _LIBCPP_INLINE_VISIBILITY
3578bool
3579operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3580           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3581{
3582    return __lhs.compare(__rhs) < 0;
3583}
3584
3585template<class _CharT, class _Traits, class _Allocator>
3586inline _LIBCPP_INLINE_VISIBILITY
3587bool
3588operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3589           const _CharT* __rhs) _NOEXCEPT
3590{
3591    return __lhs.compare(__rhs) < 0;
3592}
3593
3594template<class _CharT, class _Traits, class _Allocator>
3595inline _LIBCPP_INLINE_VISIBILITY
3596bool
3597operator< (const _CharT* __lhs,
3598           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3599{
3600    return __rhs.compare(__lhs) > 0;
3601}
3602
3603// operator>
3604
3605template<class _CharT, class _Traits, class _Allocator>
3606inline _LIBCPP_INLINE_VISIBILITY
3607bool
3608operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3609           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3610{
3611    return __rhs < __lhs;
3612}
3613
3614template<class _CharT, class _Traits, class _Allocator>
3615inline _LIBCPP_INLINE_VISIBILITY
3616bool
3617operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3618           const _CharT* __rhs) _NOEXCEPT
3619{
3620    return __rhs < __lhs;
3621}
3622
3623template<class _CharT, class _Traits, class _Allocator>
3624inline _LIBCPP_INLINE_VISIBILITY
3625bool
3626operator> (const _CharT* __lhs,
3627           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3628{
3629    return __rhs < __lhs;
3630}
3631
3632// operator<=
3633
3634template<class _CharT, class _Traits, class _Allocator>
3635inline _LIBCPP_INLINE_VISIBILITY
3636bool
3637operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3638           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3639{
3640    return !(__rhs < __lhs);
3641}
3642
3643template<class _CharT, class _Traits, class _Allocator>
3644inline _LIBCPP_INLINE_VISIBILITY
3645bool
3646operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3647           const _CharT* __rhs) _NOEXCEPT
3648{
3649    return !(__rhs < __lhs);
3650}
3651
3652template<class _CharT, class _Traits, class _Allocator>
3653inline _LIBCPP_INLINE_VISIBILITY
3654bool
3655operator<=(const _CharT* __lhs,
3656           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3657{
3658    return !(__rhs < __lhs);
3659}
3660
3661// operator>=
3662
3663template<class _CharT, class _Traits, class _Allocator>
3664inline _LIBCPP_INLINE_VISIBILITY
3665bool
3666operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3667           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3668{
3669    return !(__lhs < __rhs);
3670}
3671
3672template<class _CharT, class _Traits, class _Allocator>
3673inline _LIBCPP_INLINE_VISIBILITY
3674bool
3675operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3676           const _CharT* __rhs) _NOEXCEPT
3677{
3678    return !(__lhs < __rhs);
3679}
3680
3681template<class _CharT, class _Traits, class _Allocator>
3682inline _LIBCPP_INLINE_VISIBILITY
3683bool
3684operator>=(const _CharT* __lhs,
3685           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3686{
3687    return !(__lhs < __rhs);
3688}
3689
3690// operator +
3691
3692template<class _CharT, class _Traits, class _Allocator>
3693basic_string<_CharT, _Traits, _Allocator>
3694operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3695          const basic_string<_CharT, _Traits, _Allocator>& __rhs)
3696{
3697    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3698    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3699    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3700    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3701    __r.append(__rhs.data(), __rhs_sz);
3702    return __r;
3703}
3704
3705template<class _CharT, class _Traits, class _Allocator>
3706basic_string<_CharT, _Traits, _Allocator>
3707operator+(const _CharT* __lhs , const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3708{
3709    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3710    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = _Traits::length(__lhs);
3711    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3712    __r.__init(__lhs, __lhs_sz, __lhs_sz + __rhs_sz);
3713    __r.append(__rhs.data(), __rhs_sz);
3714    return __r;
3715}
3716
3717template<class _CharT, class _Traits, class _Allocator>
3718basic_string<_CharT, _Traits, _Allocator>
3719operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3720{
3721    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3722    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3723    __r.__init(&__lhs, 1, 1 + __rhs_sz);
3724    __r.append(__rhs.data(), __rhs_sz);
3725    return __r;
3726}
3727
3728template<class _CharT, class _Traits, class _Allocator>
3729basic_string<_CharT, _Traits, _Allocator>
3730operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs)
3731{
3732    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3733    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3734    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = _Traits::length(__rhs);
3735    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3736    __r.append(__rhs, __rhs_sz);
3737    return __r;
3738}
3739
3740template<class _CharT, class _Traits, class _Allocator>
3741basic_string<_CharT, _Traits, _Allocator>
3742operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, _CharT __rhs)
3743{
3744    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3745    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3746    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + 1);
3747    __r.push_back(__rhs);
3748    return __r;
3749}
3750
3751#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3752
3753template<class _CharT, class _Traits, class _Allocator>
3754inline _LIBCPP_INLINE_VISIBILITY
3755basic_string<_CharT, _Traits, _Allocator>
3756operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs)
3757{
3758    return _VSTD::move(__lhs.append(__rhs));
3759}
3760
3761template<class _CharT, class _Traits, class _Allocator>
3762inline _LIBCPP_INLINE_VISIBILITY
3763basic_string<_CharT, _Traits, _Allocator>
3764operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
3765{
3766    return _VSTD::move(__rhs.insert(0, __lhs));
3767}
3768
3769template<class _CharT, class _Traits, class _Allocator>
3770inline _LIBCPP_INLINE_VISIBILITY
3771basic_string<_CharT, _Traits, _Allocator>
3772operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
3773{
3774    return _VSTD::move(__lhs.append(__rhs));
3775}
3776
3777template<class _CharT, class _Traits, class _Allocator>
3778inline _LIBCPP_INLINE_VISIBILITY
3779basic_string<_CharT, _Traits, _Allocator>
3780operator+(const _CharT* __lhs , basic_string<_CharT,_Traits,_Allocator>&& __rhs)
3781{
3782    return _VSTD::move(__rhs.insert(0, __lhs));
3783}
3784
3785template<class _CharT, class _Traits, class _Allocator>
3786inline _LIBCPP_INLINE_VISIBILITY
3787basic_string<_CharT, _Traits, _Allocator>
3788operator+(_CharT __lhs, basic_string<_CharT,_Traits,_Allocator>&& __rhs)
3789{
3790    __rhs.insert(__rhs.begin(), __lhs);
3791    return _VSTD::move(__rhs);
3792}
3793
3794template<class _CharT, class _Traits, class _Allocator>
3795inline _LIBCPP_INLINE_VISIBILITY
3796basic_string<_CharT, _Traits, _Allocator>
3797operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const _CharT* __rhs)
3798{
3799    return _VSTD::move(__lhs.append(__rhs));
3800}
3801
3802template<class _CharT, class _Traits, class _Allocator>
3803inline _LIBCPP_INLINE_VISIBILITY
3804basic_string<_CharT, _Traits, _Allocator>
3805operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, _CharT __rhs)
3806{
3807    __lhs.push_back(__rhs);
3808    return _VSTD::move(__lhs);
3809}
3810
3811#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3812
3813// swap
3814
3815template<class _CharT, class _Traits, class _Allocator>
3816inline _LIBCPP_INLINE_VISIBILITY
3817void
3818swap(basic_string<_CharT, _Traits, _Allocator>& __lhs,
3819     basic_string<_CharT, _Traits, _Allocator>& __rhs)
3820     _NOEXCEPT_(_NOEXCEPT_(__lhs.swap(__rhs)))
3821{
3822    __lhs.swap(__rhs);
3823}
3824
3825#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
3826
3827typedef basic_string<char16_t> u16string;
3828typedef basic_string<char32_t> u32string;
3829
3830#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
3831
3832_LIBCPP_FUNC_VIS int                stoi  (const string& __str, size_t* __idx = 0, int __base = 10);
3833_LIBCPP_FUNC_VIS long               stol  (const string& __str, size_t* __idx = 0, int __base = 10);
3834_LIBCPP_FUNC_VIS unsigned long      stoul (const string& __str, size_t* __idx = 0, int __base = 10);
3835_LIBCPP_FUNC_VIS long long          stoll (const string& __str, size_t* __idx = 0, int __base = 10);
3836_LIBCPP_FUNC_VIS unsigned long long stoull(const string& __str, size_t* __idx = 0, int __base = 10);
3837
3838_LIBCPP_FUNC_VIS float       stof (const string& __str, size_t* __idx = 0);
3839_LIBCPP_FUNC_VIS double      stod (const string& __str, size_t* __idx = 0);
3840_LIBCPP_FUNC_VIS long double stold(const string& __str, size_t* __idx = 0);
3841
3842_LIBCPP_FUNC_VIS string to_string(int __val);
3843_LIBCPP_FUNC_VIS string to_string(unsigned __val);
3844_LIBCPP_FUNC_VIS string to_string(long __val);
3845_LIBCPP_FUNC_VIS string to_string(unsigned long __val);
3846_LIBCPP_FUNC_VIS string to_string(long long __val);
3847_LIBCPP_FUNC_VIS string to_string(unsigned long long __val);
3848_LIBCPP_FUNC_VIS string to_string(float __val);
3849_LIBCPP_FUNC_VIS string to_string(double __val);
3850_LIBCPP_FUNC_VIS string to_string(long double __val);
3851
3852_LIBCPP_FUNC_VIS int                stoi  (const wstring& __str, size_t* __idx = 0, int __base = 10);
3853_LIBCPP_FUNC_VIS long               stol  (const wstring& __str, size_t* __idx = 0, int __base = 10);
3854_LIBCPP_FUNC_VIS unsigned long      stoul (const wstring& __str, size_t* __idx = 0, int __base = 10);
3855_LIBCPP_FUNC_VIS long long          stoll (const wstring& __str, size_t* __idx = 0, int __base = 10);
3856_LIBCPP_FUNC_VIS unsigned long long stoull(const wstring& __str, size_t* __idx = 0, int __base = 10);
3857
3858_LIBCPP_FUNC_VIS float       stof (const wstring& __str, size_t* __idx = 0);
3859_LIBCPP_FUNC_VIS double      stod (const wstring& __str, size_t* __idx = 0);
3860_LIBCPP_FUNC_VIS long double stold(const wstring& __str, size_t* __idx = 0);
3861
3862_LIBCPP_FUNC_VIS wstring to_wstring(int __val);
3863_LIBCPP_FUNC_VIS wstring to_wstring(unsigned __val);
3864_LIBCPP_FUNC_VIS wstring to_wstring(long __val);
3865_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long __val);
3866_LIBCPP_FUNC_VIS wstring to_wstring(long long __val);
3867_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long long __val);
3868_LIBCPP_FUNC_VIS wstring to_wstring(float __val);
3869_LIBCPP_FUNC_VIS wstring to_wstring(double __val);
3870_LIBCPP_FUNC_VIS wstring to_wstring(long double __val);
3871
3872template<class _CharT, class _Traits, class _Allocator>
3873    const typename basic_string<_CharT, _Traits, _Allocator>::size_type
3874                   basic_string<_CharT, _Traits, _Allocator>::npos;
3875
3876template<class _CharT, class _Traits, class _Allocator>
3877struct _LIBCPP_TEMPLATE_VIS hash<basic_string<_CharT, _Traits, _Allocator> >
3878    : public unary_function<basic_string<_CharT, _Traits, _Allocator>, size_t>
3879{
3880    size_t
3881        operator()(const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT;
3882};
3883
3884template<class _CharT, class _Traits, class _Allocator>
3885size_t
3886hash<basic_string<_CharT, _Traits, _Allocator> >::operator()(
3887        const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT
3888{
3889    return __do_string_hash(__val.data(), __val.data() + __val.size());
3890}
3891
3892template<class _CharT, class _Traits, class _Allocator>
3893basic_ostream<_CharT, _Traits>&
3894operator<<(basic_ostream<_CharT, _Traits>& __os,
3895           const basic_string<_CharT, _Traits, _Allocator>& __str);
3896
3897template<class _CharT, class _Traits, class _Allocator>
3898basic_istream<_CharT, _Traits>&
3899operator>>(basic_istream<_CharT, _Traits>& __is,
3900           basic_string<_CharT, _Traits, _Allocator>& __str);
3901
3902template<class _CharT, class _Traits, class _Allocator>
3903basic_istream<_CharT, _Traits>&
3904getline(basic_istream<_CharT, _Traits>& __is,
3905        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
3906
3907template<class _CharT, class _Traits, class _Allocator>
3908inline _LIBCPP_INLINE_VISIBILITY
3909basic_istream<_CharT, _Traits>&
3910getline(basic_istream<_CharT, _Traits>& __is,
3911        basic_string<_CharT, _Traits, _Allocator>& __str);
3912
3913#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3914
3915template<class _CharT, class _Traits, class _Allocator>
3916inline _LIBCPP_INLINE_VISIBILITY
3917basic_istream<_CharT, _Traits>&
3918getline(basic_istream<_CharT, _Traits>&& __is,
3919        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
3920
3921template<class _CharT, class _Traits, class _Allocator>
3922inline _LIBCPP_INLINE_VISIBILITY
3923basic_istream<_CharT, _Traits>&
3924getline(basic_istream<_CharT, _Traits>&& __is,
3925        basic_string<_CharT, _Traits, _Allocator>& __str);
3926
3927#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3928
3929#if _LIBCPP_DEBUG_LEVEL >= 2
3930
3931template<class _CharT, class _Traits, class _Allocator>
3932bool
3933basic_string<_CharT, _Traits, _Allocator>::__dereferenceable(const const_iterator* __i) const
3934{
3935    return this->data() <= _VSTD::__to_raw_pointer(__i->base()) &&
3936           _VSTD::__to_raw_pointer(__i->base()) < this->data() + this->size();
3937}
3938
3939template<class _CharT, class _Traits, class _Allocator>
3940bool
3941basic_string<_CharT, _Traits, _Allocator>::__decrementable(const const_iterator* __i) const
3942{
3943    return this->data() < _VSTD::__to_raw_pointer(__i->base()) &&
3944           _VSTD::__to_raw_pointer(__i->base()) <= this->data() + this->size();
3945}
3946
3947template<class _CharT, class _Traits, class _Allocator>
3948bool
3949basic_string<_CharT, _Traits, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
3950{
3951    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
3952    return this->data() <= __p && __p <= this->data() + this->size();
3953}
3954
3955template<class _CharT, class _Traits, class _Allocator>
3956bool
3957basic_string<_CharT, _Traits, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
3958{
3959    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
3960    return this->data() <= __p && __p < this->data() + this->size();
3961}
3962
3963#endif  // _LIBCPP_DEBUG_LEVEL >= 2
3964
3965#if _LIBCPP_STD_VER > 11
3966// Literal suffixes for basic_string [basic.string.literals]
3967inline namespace literals
3968{
3969  inline namespace string_literals
3970  {
3971    inline _LIBCPP_INLINE_VISIBILITY
3972    basic_string<char> operator "" s( const char *__str, size_t __len )
3973    {
3974        return basic_string<char> (__str, __len);
3975    }
3976
3977    inline _LIBCPP_INLINE_VISIBILITY
3978    basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
3979    {
3980        return basic_string<wchar_t> (__str, __len);
3981    }
3982
3983    inline _LIBCPP_INLINE_VISIBILITY
3984    basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
3985    {
3986        return basic_string<char16_t> (__str, __len);
3987    }
3988
3989    inline _LIBCPP_INLINE_VISIBILITY
3990    basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
3991    {
3992        return basic_string<char32_t> (__str, __len);
3993    }
3994  }
3995}
3996#endif
3997
3998_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_string<char>)
3999_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_string<wchar_t>)
4000_LIBCPP_EXTERN_TEMPLATE(string operator+<char, char_traits<char>, allocator<char> >(char const*, string const&))
4001
4002_LIBCPP_END_NAMESPACE_STD
4003
4004#endif  // _LIBCPP_STRING
4005