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 rfind(basic_string_view<charT, traits> sv, size_type pos = npos) 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 = npos) 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 = npos) 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 <__debug>
488
489#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
490#pragma GCC system_header
491#endif
492
493_LIBCPP_PUSH_MACROS
494#include <__undef_macros>
495
496
497_LIBCPP_BEGIN_NAMESPACE_STD
498
499// fpos
500
501template <class _StateT>
502class _LIBCPP_TEMPLATE_VIS fpos
503{
504private:
505    _StateT __st_;
506    streamoff __off_;
507public:
508    _LIBCPP_INLINE_VISIBILITY fpos(streamoff __off = streamoff()) : __st_(), __off_(__off) {}
509
510    _LIBCPP_INLINE_VISIBILITY operator streamoff() const {return __off_;}
511
512    _LIBCPP_INLINE_VISIBILITY _StateT state() const {return __st_;}
513    _LIBCPP_INLINE_VISIBILITY void state(_StateT __st) {__st_ = __st;}
514
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    _LIBCPP_INLINE_VISIBILITY fpos& operator-=(streamoff __off) {__off_ -= __off; return *this;}
518    _LIBCPP_INLINE_VISIBILITY fpos  operator- (streamoff __off) const {fpos __t(*this); __t -= __off; return __t;}
519};
520
521template <class _StateT>
522inline _LIBCPP_INLINE_VISIBILITY
523streamoff operator-(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
524    {return streamoff(__x) - streamoff(__y);}
525
526template <class _StateT>
527inline _LIBCPP_INLINE_VISIBILITY
528bool operator==(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
529    {return streamoff(__x) == streamoff(__y);}
530
531template <class _StateT>
532inline _LIBCPP_INLINE_VISIBILITY
533bool operator!=(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
534    {return streamoff(__x) != streamoff(__y);}
535
536// basic_string
537
538template<class _CharT, class _Traits, class _Allocator>
539basic_string<_CharT, _Traits, _Allocator>
540operator+(const basic_string<_CharT, _Traits, _Allocator>& __x,
541          const basic_string<_CharT, _Traits, _Allocator>& __y);
542
543template<class _CharT, class _Traits, class _Allocator>
544basic_string<_CharT, _Traits, _Allocator>
545operator+(const _CharT* __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
546
547template<class _CharT, class _Traits, class _Allocator>
548basic_string<_CharT, _Traits, _Allocator>
549operator+(_CharT __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
550
551template<class _CharT, class _Traits, class _Allocator>
552basic_string<_CharT, _Traits, _Allocator>
553operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, const _CharT* __y);
554
555template<class _CharT, class _Traits, class _Allocator>
556basic_string<_CharT, _Traits, _Allocator>
557operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, _CharT __y);
558
559_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS string operator+<char, char_traits<char>, allocator<char> >(char const*, string const&))
560
561template <bool>
562class _LIBCPP_TEMPLATE_VIS __basic_string_common
563{
564protected:
565    _LIBCPP_NORETURN void __throw_length_error() const;
566    _LIBCPP_NORETURN void __throw_out_of_range() const;
567};
568
569template <bool __b>
570void
571__basic_string_common<__b>::__throw_length_error() const
572{
573    _VSTD::__throw_length_error("basic_string");
574}
575
576template <bool __b>
577void
578__basic_string_common<__b>::__throw_out_of_range() const
579{
580    _VSTD::__throw_out_of_range("basic_string");
581}
582
583_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __basic_string_common<true>)
584
585#ifdef _LIBCPP_NO_EXCEPTIONS
586template <class _Iter>
587struct __libcpp_string_gets_noexcept_iterator_impl : public true_type {};
588#elif defined(_LIBCPP_HAS_NO_NOEXCEPT)
589template <class _Iter>
590struct __libcpp_string_gets_noexcept_iterator_impl : public false_type {};
591#else
592template <class _Iter, bool = __is_forward_iterator<_Iter>::value>
593struct __libcpp_string_gets_noexcept_iterator_impl : public _LIBCPP_BOOL_CONSTANT((
594    noexcept(++(declval<_Iter&>())) && 
595    is_nothrow_assignable<_Iter&, _Iter>::value && 
596    noexcept(declval<_Iter>() == declval<_Iter>()) && 
597    noexcept(*declval<_Iter>())
598)) {};
599
600template <class _Iter> 
601struct __libcpp_string_gets_noexcept_iterator_impl<_Iter, false> : public false_type {};
602#endif
603
604
605template <class _Iter>
606struct __libcpp_string_gets_noexcept_iterator
607    : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value || __libcpp_string_gets_noexcept_iterator_impl<_Iter>::value) {};
608
609template <class _CharT, class _Traits, class _Tp>
610struct __can_be_converted_to_string_view : public _LIBCPP_BOOL_CONSTANT(
611	( is_convertible<const _Tp&, basic_string_view<_CharT, _Traits> >::value &&
612     !is_convertible<const _Tp&, const _CharT*>::value)) {};
613
614#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
615
616template <class _CharT, size_t = sizeof(_CharT)>
617struct __padding
618{
619    unsigned char __xx[sizeof(_CharT)-1];
620};
621
622template <class _CharT>
623struct __padding<_CharT, 1>
624{
625};
626
627#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
628
629template<class _CharT, class _Traits, class _Allocator>
630class _LIBCPP_TEMPLATE_VIS basic_string
631    : private __basic_string_common<true>
632{
633public:
634    typedef basic_string                                 __self;
635    typedef basic_string_view<_CharT, _Traits>           __self_view;
636    typedef _Traits                                      traits_type;
637    typedef _CharT                                       value_type;
638    typedef _Allocator                                   allocator_type;
639    typedef allocator_traits<allocator_type>             __alloc_traits;
640    typedef typename __alloc_traits::size_type           size_type;
641    typedef typename __alloc_traits::difference_type     difference_type;
642    typedef value_type&                                  reference;
643    typedef const value_type&                            const_reference;
644    typedef typename __alloc_traits::pointer             pointer;
645    typedef typename __alloc_traits::const_pointer       const_pointer;
646
647    static_assert(is_pod<value_type>::value, "Character type of basic_string must be a POD");
648    static_assert((is_same<_CharT, typename traits_type::char_type>::value),
649                  "traits_type::char_type must be the same type as CharT");
650    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
651                  "Allocator::value_type must be same type as value_type");
652#if defined(_LIBCPP_RAW_ITERATORS)
653    typedef pointer                                      iterator;
654    typedef const_pointer                                const_iterator;
655#else  // defined(_LIBCPP_RAW_ITERATORS)
656    typedef __wrap_iter<pointer>                         iterator;
657    typedef __wrap_iter<const_pointer>                   const_iterator;
658#endif  // defined(_LIBCPP_RAW_ITERATORS)
659    typedef _VSTD::reverse_iterator<iterator>             reverse_iterator;
660    typedef _VSTD::reverse_iterator<const_iterator>       const_reverse_iterator;
661
662private:
663
664#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
665
666    struct __long
667    {
668        pointer   __data_;
669        size_type __size_;
670        size_type __cap_;
671    };
672
673#ifdef _LIBCPP_BIG_ENDIAN
674    static const size_type __short_mask = 0x01;
675    static const size_type __long_mask  = 0x1ul;
676#else  // _LIBCPP_BIG_ENDIAN
677    static const size_type __short_mask = 0x80;
678    static const size_type __long_mask  = ~(size_type(~0) >> 1);
679#endif  // _LIBCPP_BIG_ENDIAN
680
681    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
682                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
683
684    struct __short
685    {
686        value_type __data_[__min_cap];
687        struct
688            : __padding<value_type>
689        {
690            unsigned char __size_;
691        };
692    };
693
694#else
695
696    struct __long
697    {
698        size_type __cap_;
699        size_type __size_;
700        pointer   __data_;
701    };
702
703#ifdef _LIBCPP_BIG_ENDIAN
704    static const size_type __short_mask = 0x80;
705    static const size_type __long_mask  = ~(size_type(~0) >> 1);
706#else  // _LIBCPP_BIG_ENDIAN
707    static const size_type __short_mask = 0x01;
708    static const size_type __long_mask  = 0x1ul;
709#endif  // _LIBCPP_BIG_ENDIAN
710
711    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
712                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
713
714    struct __short
715    {
716        union
717        {
718            unsigned char __size_;
719            value_type __lx;
720        };
721        value_type __data_[__min_cap];
722    };
723
724#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
725
726    union __ulx{__long __lx; __short __lxx;};
727
728    enum {__n_words = sizeof(__ulx) / sizeof(size_type)};
729
730    struct __raw
731    {
732        size_type __words[__n_words];
733    };
734
735    struct __rep
736    {
737        union
738        {
739            __long  __l;
740            __short __s;
741            __raw   __r;
742        };
743    };
744
745    __compressed_pair<__rep, allocator_type> __r_;
746
747public:
748    static const size_type npos = -1;
749
750    _LIBCPP_INLINE_VISIBILITY basic_string()
751        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
752
753    _LIBCPP_INLINE_VISIBILITY explicit basic_string(const allocator_type& __a)
754#if _LIBCPP_STD_VER <= 14
755        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value);
756#else
757        _NOEXCEPT;
758#endif
759
760    basic_string(const basic_string& __str);
761    basic_string(const basic_string& __str, const allocator_type& __a);
762
763#ifndef _LIBCPP_CXX03_LANG
764    _LIBCPP_INLINE_VISIBILITY
765    basic_string(basic_string&& __str)
766#if _LIBCPP_STD_VER <= 14
767        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
768#else
769        _NOEXCEPT;
770#endif
771
772    _LIBCPP_INLINE_VISIBILITY
773    basic_string(basic_string&& __str, const allocator_type& __a);
774#endif  // _LIBCPP_CXX03_LANG
775    _LIBCPP_INLINE_VISIBILITY basic_string(const _CharT* __s);
776    _LIBCPP_INLINE_VISIBILITY
777    basic_string(const _CharT* __s, const _Allocator& __a);
778    _LIBCPP_INLINE_VISIBILITY
779    basic_string(const _CharT* __s, size_type __n);
780    _LIBCPP_INLINE_VISIBILITY
781    basic_string(const _CharT* __s, size_type __n, const _Allocator& __a);
782    _LIBCPP_INLINE_VISIBILITY
783    basic_string(size_type __n, _CharT __c);
784    _LIBCPP_INLINE_VISIBILITY
785    basic_string(size_type __n, _CharT __c, const _Allocator& __a);
786    basic_string(const basic_string& __str, size_type __pos, size_type __n,
787                 const _Allocator& __a = _Allocator());
788    _LIBCPP_INLINE_VISIBILITY
789    basic_string(const basic_string& __str, size_type __pos,
790                 const _Allocator& __a = _Allocator());
791    template<class _Tp>
792        _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
793        basic_string(const _Tp& __t, size_type __pos, size_type __n,
794                     const allocator_type& __a = allocator_type(),
795                     typename enable_if<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, void>::type* = 0);
796    _LIBCPP_INLINE_VISIBILITY explicit
797    basic_string(__self_view __sv);
798    _LIBCPP_INLINE_VISIBILITY
799    basic_string(__self_view __sv, const _Allocator& __a);
800    template<class _InputIterator>
801        _LIBCPP_INLINE_VISIBILITY
802        basic_string(_InputIterator __first, _InputIterator __last);
803    template<class _InputIterator>
804        _LIBCPP_INLINE_VISIBILITY
805        basic_string(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
806#ifndef _LIBCPP_CXX03_LANG
807    _LIBCPP_INLINE_VISIBILITY
808    basic_string(initializer_list<_CharT> __il);
809    _LIBCPP_INLINE_VISIBILITY
810    basic_string(initializer_list<_CharT> __il, const _Allocator& __a);
811#endif  // _LIBCPP_CXX03_LANG
812
813    inline ~basic_string();
814
815    _LIBCPP_INLINE_VISIBILITY
816    operator __self_view() const _NOEXCEPT { return __self_view(data(), size()); }
817
818    basic_string& operator=(const basic_string& __str);
819
820#ifndef _LIBCPP_CXX03_LANG
821    template <class = void>
822#endif
823    _LIBCPP_INLINE_VISIBILITY
824    basic_string& operator=(__self_view __sv)  {return assign(__sv);}
825#ifndef _LIBCPP_CXX03_LANG
826    _LIBCPP_INLINE_VISIBILITY
827    basic_string& operator=(basic_string&& __str)
828        _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value));
829     _LIBCPP_INLINE_VISIBILITY
830    basic_string& operator=(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
831#endif
832    _LIBCPP_INLINE_VISIBILITY basic_string& operator=(const value_type* __s) {return assign(__s);}
833    basic_string& operator=(value_type __c);
834
835#if _LIBCPP_DEBUG_LEVEL >= 2
836    _LIBCPP_INLINE_VISIBILITY
837    iterator begin() _NOEXCEPT
838        {return iterator(this, __get_pointer());}
839    _LIBCPP_INLINE_VISIBILITY
840    const_iterator begin() const _NOEXCEPT
841        {return const_iterator(this, __get_pointer());}
842    _LIBCPP_INLINE_VISIBILITY
843    iterator end() _NOEXCEPT
844        {return iterator(this, __get_pointer() + size());}
845    _LIBCPP_INLINE_VISIBILITY
846    const_iterator end() const _NOEXCEPT
847        {return const_iterator(this, __get_pointer() + size());}
848#else
849    _LIBCPP_INLINE_VISIBILITY
850    iterator begin() _NOEXCEPT
851        {return iterator(__get_pointer());}
852    _LIBCPP_INLINE_VISIBILITY
853    const_iterator begin() const _NOEXCEPT
854        {return const_iterator(__get_pointer());}
855    _LIBCPP_INLINE_VISIBILITY
856    iterator end() _NOEXCEPT
857        {return iterator(__get_pointer() + size());}
858    _LIBCPP_INLINE_VISIBILITY
859    const_iterator end() const _NOEXCEPT
860        {return const_iterator(__get_pointer() + size());}
861#endif  // _LIBCPP_DEBUG_LEVEL >= 2
862    _LIBCPP_INLINE_VISIBILITY
863    reverse_iterator rbegin() _NOEXCEPT
864        {return reverse_iterator(end());}
865    _LIBCPP_INLINE_VISIBILITY
866    const_reverse_iterator rbegin() const _NOEXCEPT
867        {return const_reverse_iterator(end());}
868    _LIBCPP_INLINE_VISIBILITY
869    reverse_iterator rend() _NOEXCEPT
870        {return reverse_iterator(begin());}
871    _LIBCPP_INLINE_VISIBILITY
872    const_reverse_iterator rend() const _NOEXCEPT
873        {return const_reverse_iterator(begin());}
874
875    _LIBCPP_INLINE_VISIBILITY
876    const_iterator cbegin() const _NOEXCEPT
877        {return begin();}
878    _LIBCPP_INLINE_VISIBILITY
879    const_iterator cend() const _NOEXCEPT
880        {return end();}
881    _LIBCPP_INLINE_VISIBILITY
882    const_reverse_iterator crbegin() const _NOEXCEPT
883        {return rbegin();}
884    _LIBCPP_INLINE_VISIBILITY
885    const_reverse_iterator crend() const _NOEXCEPT
886        {return rend();}
887
888    _LIBCPP_INLINE_VISIBILITY size_type size() const _NOEXCEPT
889        {return __is_long() ? __get_long_size() : __get_short_size();}
890    _LIBCPP_INLINE_VISIBILITY size_type length() const _NOEXCEPT {return size();}
891    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT;
892    _LIBCPP_INLINE_VISIBILITY size_type capacity() const _NOEXCEPT
893        {return (__is_long() ? __get_long_cap()
894                             : static_cast<size_type>(__min_cap)) - 1;}
895
896    void resize(size_type __n, value_type __c);
897    _LIBCPP_INLINE_VISIBILITY void resize(size_type __n) {resize(__n, value_type());}
898
899    void reserve(size_type __res_arg = 0);
900    _LIBCPP_INLINE_VISIBILITY
901    void shrink_to_fit() _NOEXCEPT {reserve();}
902    _LIBCPP_INLINE_VISIBILITY
903    void clear() _NOEXCEPT;
904    _LIBCPP_INLINE_VISIBILITY bool empty() const _NOEXCEPT {return size() == 0;}
905
906    _LIBCPP_INLINE_VISIBILITY const_reference operator[](size_type __pos) const _NOEXCEPT;
907    _LIBCPP_INLINE_VISIBILITY reference       operator[](size_type __pos)       _NOEXCEPT;
908
909    const_reference at(size_type __n) const;
910    reference       at(size_type __n);
911
912    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const basic_string& __str) {return append(__str);}
913    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(__self_view __sv)          {return append(__sv);}
914    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const value_type* __s)     {return append(__s);}
915    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(value_type __c)            {push_back(__c); return *this;}
916#ifndef _LIBCPP_CXX03_LANG
917    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(initializer_list<value_type> __il) {return append(__il);}
918#endif  // _LIBCPP_CXX03_LANG
919
920    _LIBCPP_INLINE_VISIBILITY
921    basic_string& append(const basic_string& __str);
922    _LIBCPP_INLINE_VISIBILITY
923    basic_string& append(__self_view __sv) { return append(__sv.data(), __sv.size()); }
924    basic_string& append(const basic_string& __str, size_type __pos, size_type __n=npos);
925    template <class _Tp>
926    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
927    typename enable_if
928        <
929            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
930            basic_string&
931        >::type
932                  append(const _Tp& __t, size_type __pos, size_type __n=npos);
933    basic_string& append(const value_type* __s, size_type __n);
934    basic_string& append(const value_type* __s);
935    basic_string& append(size_type __n, value_type __c);
936    template <class _ForwardIterator>
937    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
938    basic_string& __append_forward_unsafe(_ForwardIterator, _ForwardIterator);
939    template<class _InputIterator>
940    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
941    typename enable_if
942        <
943            __is_exactly_input_iterator<_InputIterator>::value
944                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
945            basic_string&
946        >::type
947    _LIBCPP_INLINE_VISIBILITY
948    append(_InputIterator __first, _InputIterator __last) {
949      const basic_string __temp (__first, __last, __alloc());
950      append(__temp.data(), __temp.size());
951      return *this;
952    }
953    template<class _ForwardIterator>
954    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
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_CXX03_LANG
967    _LIBCPP_INLINE_VISIBILITY
968    basic_string& append(initializer_list<value_type> __il) {return append(__il.begin(), __il.size());}
969#endif  // _LIBCPP_CXX03_LANG
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_CXX03_LANG
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    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
992    typename enable_if
993        <
994            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
995            basic_string&
996        >::type
997                  assign(const _Tp & __t, size_type __pos, size_type __n=npos);
998    basic_string& assign(const value_type* __s, size_type __n);
999    basic_string& assign(const value_type* __s);
1000    basic_string& assign(size_type __n, value_type __c);
1001    template<class _InputIterator>
1002    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1003    typename enable_if
1004        <
1005           __is_exactly_input_iterator<_InputIterator>::value
1006                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
1007            basic_string&
1008        >::type
1009        assign(_InputIterator __first, _InputIterator __last);
1010    template<class _ForwardIterator>
1011    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1012    typename enable_if
1013        <
1014            __is_forward_iterator<_ForwardIterator>::value
1015                 && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
1016            basic_string&
1017        >::type
1018        assign(_ForwardIterator __first, _ForwardIterator __last);
1019#ifndef _LIBCPP_CXX03_LANG
1020    _LIBCPP_INLINE_VISIBILITY
1021    basic_string& assign(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
1022#endif  // _LIBCPP_CXX03_LANG
1023
1024    _LIBCPP_INLINE_VISIBILITY
1025    basic_string& insert(size_type __pos1, const basic_string& __str);
1026    _LIBCPP_INLINE_VISIBILITY
1027    basic_string& insert(size_type __pos1, __self_view __sv) { return insert(__pos1, __sv.data(), __sv.size()); }
1028    template <class _Tp>
1029    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1030    typename enable_if
1031        <
1032            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1033            basic_string&
1034        >::type
1035                  insert(size_type __pos1, const _Tp& __t, size_type __pos2, size_type __n=npos);
1036    basic_string& insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n=npos);
1037    basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
1038    basic_string& insert(size_type __pos, const value_type* __s);
1039    basic_string& insert(size_type __pos, size_type __n, value_type __c);
1040    iterator      insert(const_iterator __pos, value_type __c);
1041    _LIBCPP_INLINE_VISIBILITY
1042    iterator      insert(const_iterator __pos, size_type __n, value_type __c);
1043    template<class _InputIterator>
1044    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1045    typename enable_if
1046        <
1047           __is_exactly_input_iterator<_InputIterator>::value
1048                || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
1049            iterator
1050        >::type
1051        insert(const_iterator __pos, _InputIterator __first, _InputIterator __last);
1052    template<class _ForwardIterator>
1053    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1054    typename enable_if
1055        <
1056            __is_forward_iterator<_ForwardIterator>::value
1057                 && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
1058            iterator
1059        >::type
1060        insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last);
1061#ifndef _LIBCPP_CXX03_LANG
1062    _LIBCPP_INLINE_VISIBILITY
1063    iterator insert(const_iterator __pos, initializer_list<value_type> __il)
1064                    {return insert(__pos, __il.begin(), __il.end());}
1065#endif  // _LIBCPP_CXX03_LANG
1066
1067    basic_string& erase(size_type __pos = 0, size_type __n = npos);
1068    _LIBCPP_INLINE_VISIBILITY
1069    iterator      erase(const_iterator __pos);
1070    _LIBCPP_INLINE_VISIBILITY
1071    iterator      erase(const_iterator __first, const_iterator __last);
1072
1073    _LIBCPP_INLINE_VISIBILITY
1074    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str);
1075    _LIBCPP_INLINE_VISIBILITY
1076    basic_string& replace(size_type __pos1, size_type __n1, __self_view __sv) { return replace(__pos1, __n1, __sv.data(), __sv.size()); }
1077    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos);
1078    template <class _Tp>
1079    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1080    typename enable_if
1081        <
1082            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1083            basic_string&
1084        >::type
1085                  replace(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2=npos);
1086    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2);
1087    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s);
1088    basic_string& replace(size_type __pos, size_type __n1, size_type __n2, value_type __c);
1089    _LIBCPP_INLINE_VISIBILITY
1090    basic_string& replace(const_iterator __i1, const_iterator __i2, const basic_string& __str);
1091    _LIBCPP_INLINE_VISIBILITY
1092    basic_string& replace(const_iterator __i1, const_iterator __i2, __self_view __sv) { return replace(__i1 - begin(), __i2 - __i1, __sv); }
1093    _LIBCPP_INLINE_VISIBILITY
1094    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n);
1095    _LIBCPP_INLINE_VISIBILITY
1096    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s);
1097    _LIBCPP_INLINE_VISIBILITY
1098    basic_string& replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c);
1099    template<class _InputIterator>
1100    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
1101    typename enable_if
1102        <
1103            __is_input_iterator<_InputIterator>::value,
1104            basic_string&
1105        >::type
1106        replace(const_iterator __i1, const_iterator __i2, _InputIterator __j1, _InputIterator __j2);
1107#ifndef _LIBCPP_CXX03_LANG
1108    _LIBCPP_INLINE_VISIBILITY
1109    basic_string& replace(const_iterator __i1, const_iterator __i2, initializer_list<value_type> __il)
1110        {return replace(__i1, __i2, __il.begin(), __il.end());}
1111#endif  // _LIBCPP_CXX03_LANG
1112
1113    size_type copy(value_type* __s, size_type __n, size_type __pos = 0) const;
1114    _LIBCPP_INLINE_VISIBILITY
1115    basic_string substr(size_type __pos = 0, size_type __n = npos) const;
1116
1117    _LIBCPP_INLINE_VISIBILITY
1118    void swap(basic_string& __str)
1119#if _LIBCPP_STD_VER >= 14
1120        _NOEXCEPT_DEBUG;
1121#else
1122        _NOEXCEPT_DEBUG_(!__alloc_traits::propagate_on_container_swap::value ||
1123                    __is_nothrow_swappable<allocator_type>::value);
1124#endif
1125
1126    _LIBCPP_INLINE_VISIBILITY
1127    const value_type* c_str() const _NOEXCEPT {return data();}
1128    _LIBCPP_INLINE_VISIBILITY
1129    const value_type* data() const _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
1130#if _LIBCPP_STD_VER > 14
1131    _LIBCPP_INLINE_VISIBILITY
1132    value_type* data()             _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
1133#endif
1134
1135    _LIBCPP_INLINE_VISIBILITY
1136    allocator_type get_allocator() const _NOEXCEPT {return __alloc();}
1137
1138    _LIBCPP_INLINE_VISIBILITY
1139    size_type find(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1140    _LIBCPP_INLINE_VISIBILITY
1141    size_type find(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1142    size_type find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1143    _LIBCPP_INLINE_VISIBILITY
1144    size_type find(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1145    size_type find(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1146
1147    _LIBCPP_INLINE_VISIBILITY
1148    size_type rfind(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1149    _LIBCPP_INLINE_VISIBILITY
1150    size_type rfind(__self_view __sv, size_type __pos = npos) const _NOEXCEPT;
1151    size_type rfind(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1152    _LIBCPP_INLINE_VISIBILITY
1153    size_type rfind(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1154    size_type rfind(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1155
1156    _LIBCPP_INLINE_VISIBILITY
1157    size_type find_first_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1158    _LIBCPP_INLINE_VISIBILITY
1159    size_type find_first_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1160    size_type find_first_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1161    _LIBCPP_INLINE_VISIBILITY
1162    size_type find_first_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1163    _LIBCPP_INLINE_VISIBILITY
1164    size_type find_first_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1165
1166    _LIBCPP_INLINE_VISIBILITY
1167    size_type find_last_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1168    _LIBCPP_INLINE_VISIBILITY
1169    size_type find_last_of(__self_view __sv, size_type __pos = npos) const _NOEXCEPT;
1170    size_type find_last_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1171    _LIBCPP_INLINE_VISIBILITY
1172    size_type find_last_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1173    _LIBCPP_INLINE_VISIBILITY
1174    size_type find_last_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1175
1176    _LIBCPP_INLINE_VISIBILITY
1177    size_type find_first_not_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1178    _LIBCPP_INLINE_VISIBILITY
1179    size_type find_first_not_of(__self_view __sv, size_type __pos = 0) const _NOEXCEPT;
1180    size_type find_first_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1181    _LIBCPP_INLINE_VISIBILITY
1182    size_type find_first_not_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1183    _LIBCPP_INLINE_VISIBILITY
1184    size_type find_first_not_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1185
1186    _LIBCPP_INLINE_VISIBILITY
1187    size_type find_last_not_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1188    _LIBCPP_INLINE_VISIBILITY
1189    size_type find_last_not_of(__self_view __sv, size_type __pos = npos) const _NOEXCEPT;
1190    size_type find_last_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1191    _LIBCPP_INLINE_VISIBILITY
1192    size_type find_last_not_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1193    _LIBCPP_INLINE_VISIBILITY
1194    size_type find_last_not_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1195
1196    _LIBCPP_INLINE_VISIBILITY
1197    int compare(const basic_string& __str) const _NOEXCEPT;
1198    _LIBCPP_INLINE_VISIBILITY
1199    int compare(__self_view __sv) const _NOEXCEPT;
1200    _LIBCPP_INLINE_VISIBILITY
1201    int compare(size_type __pos1, size_type __n1, __self_view __sv) const;
1202    _LIBCPP_INLINE_VISIBILITY
1203    int compare(size_type __pos1, size_type __n1, const basic_string& __str) const;
1204    int compare(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos) const;
1205    template <class _Tp>
1206    inline _LIBCPP_INLINE_VISIBILITY
1207        typename enable_if
1208        <
1209            __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
1210            int
1211        >::type
1212        compare(size_type __pos1, size_type __n1, const _Tp& __t, size_type __pos2, size_type __n2=npos) const;
1213    int compare(const value_type* __s) const _NOEXCEPT;
1214    int compare(size_type __pos1, size_type __n1, const value_type* __s) const;
1215    int compare(size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const;
1216
1217    _LIBCPP_INLINE_VISIBILITY bool __invariants() const;
1218
1219    _LIBCPP_INLINE_VISIBILITY
1220    bool __is_long() const _NOEXCEPT
1221        {return bool(__r_.first().__s.__size_ & __short_mask);}
1222
1223#if _LIBCPP_DEBUG_LEVEL >= 2
1224
1225    bool __dereferenceable(const const_iterator* __i) const;
1226    bool __decrementable(const const_iterator* __i) const;
1227    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
1228    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
1229
1230#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1231
1232private:
1233    _LIBCPP_INLINE_VISIBILITY
1234    allocator_type& __alloc() _NOEXCEPT
1235        {return __r_.second();}
1236    _LIBCPP_INLINE_VISIBILITY
1237    const allocator_type& __alloc() const _NOEXCEPT
1238        {return __r_.second();}
1239
1240#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1241
1242    _LIBCPP_INLINE_VISIBILITY
1243    void __set_short_size(size_type __s) _NOEXCEPT
1244#   ifdef _LIBCPP_BIG_ENDIAN
1245        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1246#   else
1247        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1248#   endif
1249
1250    _LIBCPP_INLINE_VISIBILITY
1251    size_type __get_short_size() const _NOEXCEPT
1252#   ifdef _LIBCPP_BIG_ENDIAN
1253        {return __r_.first().__s.__size_ >> 1;}
1254#   else
1255        {return __r_.first().__s.__size_;}
1256#   endif
1257
1258#else  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1259
1260    _LIBCPP_INLINE_VISIBILITY
1261    void __set_short_size(size_type __s) _NOEXCEPT
1262#   ifdef _LIBCPP_BIG_ENDIAN
1263        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1264#   else
1265        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1266#   endif
1267
1268    _LIBCPP_INLINE_VISIBILITY
1269    size_type __get_short_size() const _NOEXCEPT
1270#   ifdef _LIBCPP_BIG_ENDIAN
1271        {return __r_.first().__s.__size_;}
1272#   else
1273        {return __r_.first().__s.__size_ >> 1;}
1274#   endif
1275
1276#endif  // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
1277
1278    _LIBCPP_INLINE_VISIBILITY
1279    void __set_long_size(size_type __s) _NOEXCEPT
1280        {__r_.first().__l.__size_ = __s;}
1281    _LIBCPP_INLINE_VISIBILITY
1282    size_type __get_long_size() const _NOEXCEPT
1283        {return __r_.first().__l.__size_;}
1284    _LIBCPP_INLINE_VISIBILITY
1285    void __set_size(size_type __s) _NOEXCEPT
1286        {if (__is_long()) __set_long_size(__s); else __set_short_size(__s);}
1287
1288    _LIBCPP_INLINE_VISIBILITY
1289    void __set_long_cap(size_type __s) _NOEXCEPT
1290        {__r_.first().__l.__cap_  = __long_mask | __s;}
1291    _LIBCPP_INLINE_VISIBILITY
1292    size_type __get_long_cap() const _NOEXCEPT
1293        {return __r_.first().__l.__cap_ & size_type(~__long_mask);}
1294
1295    _LIBCPP_INLINE_VISIBILITY
1296    void __set_long_pointer(pointer __p) _NOEXCEPT
1297        {__r_.first().__l.__data_ = __p;}
1298    _LIBCPP_INLINE_VISIBILITY
1299    pointer __get_long_pointer() _NOEXCEPT
1300        {return __r_.first().__l.__data_;}
1301    _LIBCPP_INLINE_VISIBILITY
1302    const_pointer __get_long_pointer() const _NOEXCEPT
1303        {return __r_.first().__l.__data_;}
1304    _LIBCPP_INLINE_VISIBILITY
1305    pointer __get_short_pointer() _NOEXCEPT
1306        {return pointer_traits<pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1307    _LIBCPP_INLINE_VISIBILITY
1308    const_pointer __get_short_pointer() const _NOEXCEPT
1309        {return pointer_traits<const_pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1310    _LIBCPP_INLINE_VISIBILITY
1311    pointer __get_pointer() _NOEXCEPT
1312        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1313    _LIBCPP_INLINE_VISIBILITY
1314    const_pointer __get_pointer() const _NOEXCEPT
1315        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1316
1317    _LIBCPP_INLINE_VISIBILITY
1318    void __zero() _NOEXCEPT
1319        {
1320            size_type (&__a)[__n_words] = __r_.first().__r.__words;
1321            for (unsigned __i = 0; __i < __n_words; ++__i)
1322                __a[__i] = 0;
1323        }
1324
1325    template <size_type __a> static
1326        _LIBCPP_INLINE_VISIBILITY
1327        size_type __align_it(size_type __s) _NOEXCEPT
1328            {return (__s + (__a-1)) & ~(__a-1);}
1329    enum {__alignment = 16};
1330    static _LIBCPP_INLINE_VISIBILITY
1331    size_type __recommend(size_type __s) _NOEXCEPT
1332        {return (__s < __min_cap ? static_cast<size_type>(__min_cap) :
1333                 __align_it<sizeof(value_type) < __alignment ?
1334                            __alignment/sizeof(value_type) : 1 > (__s+1)) - 1;}
1335
1336    inline
1337    void __init(const value_type* __s, size_type __sz, size_type __reserve);
1338    inline
1339    void __init(const value_type* __s, size_type __sz);
1340    inline
1341    void __init(size_type __n, value_type __c);
1342
1343    template <class _InputIterator>
1344    inline
1345    typename enable_if
1346    <
1347        __is_exactly_input_iterator<_InputIterator>::value,
1348        void
1349    >::type
1350    __init(_InputIterator __first, _InputIterator __last);
1351
1352    template <class _ForwardIterator>
1353    inline
1354    typename enable_if
1355    <
1356        __is_forward_iterator<_ForwardIterator>::value,
1357        void
1358    >::type
1359    __init(_ForwardIterator __first, _ForwardIterator __last);
1360
1361    void __grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1362                   size_type __n_copy,  size_type __n_del,     size_type __n_add = 0);
1363    void __grow_by_and_replace(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1364                               size_type __n_copy,  size_type __n_del,
1365                               size_type __n_add, const value_type* __p_new_stuff);
1366
1367    _LIBCPP_INLINE_VISIBILITY
1368    void __erase_to_end(size_type __pos);
1369
1370    _LIBCPP_INLINE_VISIBILITY
1371    void __copy_assign_alloc(const basic_string& __str)
1372        {__copy_assign_alloc(__str, integral_constant<bool,
1373                      __alloc_traits::propagate_on_container_copy_assignment::value>());}
1374
1375    _LIBCPP_INLINE_VISIBILITY
1376    void __copy_assign_alloc(const basic_string& __str, true_type)
1377        {
1378            if (__alloc() == __str.__alloc())
1379                __alloc() = __str.__alloc();
1380            else
1381            {
1382                if (!__str.__is_long())
1383                {
1384                    clear();
1385                    shrink_to_fit();
1386                    __alloc() = __str.__alloc();
1387                }
1388                else
1389                {
1390                    allocator_type __a = __str.__alloc();
1391                    pointer __p = __alloc_traits::allocate(__a, __str.__get_long_cap());
1392                    clear();
1393                    shrink_to_fit();
1394                    __alloc() = _VSTD::move(__a);
1395                    __set_long_pointer(__p);
1396                    __set_long_cap(__str.__get_long_cap());
1397                    __set_long_size(__str.size());
1398                }
1399            }
1400        }
1401
1402    _LIBCPP_INLINE_VISIBILITY
1403    void __copy_assign_alloc(const basic_string&, false_type) _NOEXCEPT
1404        {}
1405
1406#ifndef _LIBCPP_CXX03_LANG
1407    _LIBCPP_INLINE_VISIBILITY
1408    void __move_assign(basic_string& __str, false_type)
1409        _NOEXCEPT_(__alloc_traits::is_always_equal::value);
1410    _LIBCPP_INLINE_VISIBILITY
1411    void __move_assign(basic_string& __str, true_type)
1412#if _LIBCPP_STD_VER > 14
1413        _NOEXCEPT;
1414#else
1415        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
1416#endif
1417#endif
1418
1419    _LIBCPP_INLINE_VISIBILITY
1420    void
1421    __move_assign_alloc(basic_string& __str)
1422        _NOEXCEPT_(
1423            !__alloc_traits::propagate_on_container_move_assignment::value ||
1424            is_nothrow_move_assignable<allocator_type>::value)
1425    {__move_assign_alloc(__str, integral_constant<bool,
1426                      __alloc_traits::propagate_on_container_move_assignment::value>());}
1427
1428    _LIBCPP_INLINE_VISIBILITY
1429    void __move_assign_alloc(basic_string& __c, true_type)
1430        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1431        {
1432            __alloc() = _VSTD::move(__c.__alloc());
1433        }
1434
1435    _LIBCPP_INLINE_VISIBILITY
1436    void __move_assign_alloc(basic_string&, false_type)
1437        _NOEXCEPT
1438        {}
1439
1440    _LIBCPP_INLINE_VISIBILITY void __invalidate_all_iterators();
1441    _LIBCPP_INLINE_VISIBILITY void __invalidate_iterators_past(size_type);
1442
1443    friend basic_string operator+<>(const basic_string&, const basic_string&);
1444    friend basic_string operator+<>(const value_type*, const basic_string&);
1445    friend basic_string operator+<>(value_type, const basic_string&);
1446    friend basic_string operator+<>(const basic_string&, const value_type*);
1447    friend basic_string operator+<>(const basic_string&, value_type);
1448};
1449
1450template <class _CharT, class _Traits, class _Allocator>
1451inline _LIBCPP_INLINE_VISIBILITY
1452void
1453basic_string<_CharT, _Traits, _Allocator>::__invalidate_all_iterators()
1454{
1455#if _LIBCPP_DEBUG_LEVEL >= 2
1456    __get_db()->__invalidate_all(this);
1457#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1458}
1459
1460template <class _CharT, class _Traits, class _Allocator>
1461inline _LIBCPP_INLINE_VISIBILITY
1462void
1463basic_string<_CharT, _Traits, _Allocator>::__invalidate_iterators_past(size_type
1464#if _LIBCPP_DEBUG_LEVEL >= 2
1465                                                                        __pos
1466#endif
1467                                                                      )
1468{
1469#if _LIBCPP_DEBUG_LEVEL >= 2
1470    __c_node* __c = __get_db()->__find_c_and_lock(this);
1471    if (__c)
1472    {
1473        const_pointer __new_last = __get_pointer() + __pos;
1474        for (__i_node** __p = __c->end_; __p != __c->beg_; )
1475        {
1476            --__p;
1477            const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
1478            if (__i->base() > __new_last)
1479            {
1480                (*__p)->__c_ = nullptr;
1481                if (--__c->end_ != __p)
1482                    memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
1483            }
1484        }
1485        __get_db()->unlock();
1486    }
1487#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1488}
1489
1490template <class _CharT, class _Traits, class _Allocator>
1491inline _LIBCPP_INLINE_VISIBILITY
1492basic_string<_CharT, _Traits, _Allocator>::basic_string()
1493    _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
1494{
1495#if _LIBCPP_DEBUG_LEVEL >= 2
1496    __get_db()->__insert_c(this);
1497#endif
1498    __zero();
1499}
1500
1501template <class _CharT, class _Traits, class _Allocator>
1502inline _LIBCPP_INLINE_VISIBILITY
1503basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __a)
1504#if _LIBCPP_STD_VER <= 14
1505        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
1506#else
1507        _NOEXCEPT
1508#endif
1509: __r_(__second_tag(), __a)
1510{
1511#if _LIBCPP_DEBUG_LEVEL >= 2
1512    __get_db()->__insert_c(this);
1513#endif
1514    __zero();
1515}
1516
1517template <class _CharT, class _Traits, class _Allocator>
1518void basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s,
1519                                                       size_type __sz,
1520                                                       size_type __reserve)
1521{
1522    if (__reserve > max_size())
1523        this->__throw_length_error();
1524    pointer __p;
1525    if (__reserve < __min_cap)
1526    {
1527        __set_short_size(__sz);
1528        __p = __get_short_pointer();
1529    }
1530    else
1531    {
1532        size_type __cap = __recommend(__reserve);
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>
1543void
1544basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz)
1545{
1546    if (__sz > max_size())
1547        this->__throw_length_error();
1548    pointer __p;
1549    if (__sz < __min_cap)
1550    {
1551        __set_short_size(__sz);
1552        __p = __get_short_pointer();
1553    }
1554    else
1555    {
1556        size_type __cap = __recommend(__sz);
1557        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1558        __set_long_pointer(__p);
1559        __set_long_cap(__cap+1);
1560        __set_long_size(__sz);
1561    }
1562    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
1563    traits_type::assign(__p[__sz], value_type());
1564}
1565
1566template <class _CharT, class _Traits, class _Allocator>
1567inline _LIBCPP_INLINE_VISIBILITY
1568basic_string<_CharT, _Traits, _Allocator>::basic_string(const _CharT* __s)
1569{
1570    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*) detected nullptr");
1571    __init(__s, traits_type::length(__s));
1572#if _LIBCPP_DEBUG_LEVEL >= 2
1573    __get_db()->__insert_c(this);
1574#endif
1575}
1576
1577template <class _CharT, class _Traits, class _Allocator>
1578inline _LIBCPP_INLINE_VISIBILITY
1579basic_string<_CharT, _Traits, _Allocator>::basic_string(const _CharT* __s, const _Allocator& __a)
1580    : __r_(__second_tag(), __a)
1581{
1582    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*, allocator) detected nullptr");
1583    __init(__s, traits_type::length(__s));
1584#if _LIBCPP_DEBUG_LEVEL >= 2
1585    __get_db()->__insert_c(this);
1586#endif
1587}
1588
1589template <class _CharT, class _Traits, class _Allocator>
1590inline _LIBCPP_INLINE_VISIBILITY
1591basic_string<_CharT, _Traits, _Allocator>::basic_string(const _CharT* __s, size_type __n)
1592{
1593    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n) detected nullptr");
1594    __init(__s, __n);
1595#if _LIBCPP_DEBUG_LEVEL >= 2
1596    __get_db()->__insert_c(this);
1597#endif
1598}
1599
1600template <class _CharT, class _Traits, class _Allocator>
1601inline _LIBCPP_INLINE_VISIBILITY
1602basic_string<_CharT, _Traits, _Allocator>::basic_string(const _CharT* __s, size_type __n, const _Allocator& __a)
1603    : __r_(__second_tag(), __a)
1604{
1605    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n, allocator) detected nullptr");
1606    __init(__s, __n);
1607#if _LIBCPP_DEBUG_LEVEL >= 2
1608    __get_db()->__insert_c(this);
1609#endif
1610}
1611
1612template <class _CharT, class _Traits, class _Allocator>
1613basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str)
1614    : __r_(__second_tag(), __alloc_traits::select_on_container_copy_construction(__str.__alloc()))
1615{
1616    if (!__str.__is_long())
1617        __r_.first().__r = __str.__r_.first().__r;
1618    else
1619        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1620#if _LIBCPP_DEBUG_LEVEL >= 2
1621    __get_db()->__insert_c(this);
1622#endif
1623}
1624
1625template <class _CharT, class _Traits, class _Allocator>
1626basic_string<_CharT, _Traits, _Allocator>::basic_string(
1627    const basic_string& __str, const allocator_type& __a)
1628    : __r_(__second_tag(), __a)
1629{
1630    if (!__str.__is_long())
1631        __r_.first().__r = __str.__r_.first().__r;
1632    else
1633        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1634#if _LIBCPP_DEBUG_LEVEL >= 2
1635    __get_db()->__insert_c(this);
1636#endif
1637}
1638
1639#ifndef _LIBCPP_CXX03_LANG
1640
1641template <class _CharT, class _Traits, class _Allocator>
1642inline _LIBCPP_INLINE_VISIBILITY
1643basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str)
1644#if _LIBCPP_STD_VER <= 14
1645        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
1646#else
1647        _NOEXCEPT
1648#endif
1649    : __r_(_VSTD::move(__str.__r_))
1650{
1651    __str.__zero();
1652#if _LIBCPP_DEBUG_LEVEL >= 2
1653    __get_db()->__insert_c(this);
1654    if (__is_long())
1655        __get_db()->swap(this, &__str);
1656#endif
1657}
1658
1659template <class _CharT, class _Traits, class _Allocator>
1660inline _LIBCPP_INLINE_VISIBILITY
1661basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str, const allocator_type& __a)
1662    : __r_(__second_tag(), __a)
1663{
1664    if (__str.__is_long() && __a != __str.__alloc()) // copy, not move
1665        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
1666    else
1667    {
1668        __r_.first().__r = __str.__r_.first().__r;
1669        __str.__zero();
1670    }
1671#if _LIBCPP_DEBUG_LEVEL >= 2
1672    __get_db()->__insert_c(this);
1673    if (__is_long())
1674        __get_db()->swap(this, &__str);
1675#endif
1676}
1677
1678#endif  // _LIBCPP_CXX03_LANG
1679
1680template <class _CharT, class _Traits, class _Allocator>
1681void
1682basic_string<_CharT, _Traits, _Allocator>::__init(size_type __n, value_type __c)
1683{
1684    if (__n > max_size())
1685        this->__throw_length_error();
1686    pointer __p;
1687    if (__n < __min_cap)
1688    {
1689        __set_short_size(__n);
1690        __p = __get_short_pointer();
1691    }
1692    else
1693    {
1694        size_type __cap = __recommend(__n);
1695        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1696        __set_long_pointer(__p);
1697        __set_long_cap(__cap+1);
1698        __set_long_size(__n);
1699    }
1700    traits_type::assign(_VSTD::__to_raw_pointer(__p), __n, __c);
1701    traits_type::assign(__p[__n], value_type());
1702}
1703
1704template <class _CharT, class _Traits, class _Allocator>
1705inline _LIBCPP_INLINE_VISIBILITY
1706basic_string<_CharT, _Traits, _Allocator>::basic_string(size_type __n, _CharT __c)
1707{
1708    __init(__n, __c);
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(size_type __n, _CharT __c, const _Allocator& __a)
1717    : __r_(__second_tag(), __a)
1718{
1719    __init(__n, __c);
1720#if _LIBCPP_DEBUG_LEVEL >= 2
1721    __get_db()->__insert_c(this);
1722#endif
1723}
1724
1725template <class _CharT, class _Traits, class _Allocator>
1726basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str,
1727                                                        size_type __pos, size_type __n,
1728                                                        const _Allocator& __a)
1729    : __r_(__second_tag(), __a)
1730{
1731    size_type __str_sz = __str.size();
1732    if (__pos > __str_sz)
1733        this->__throw_out_of_range();
1734    __init(__str.data() + __pos, _VSTD::min(__n, __str_sz - __pos));
1735#if _LIBCPP_DEBUG_LEVEL >= 2
1736    __get_db()->__insert_c(this);
1737#endif
1738}
1739
1740template <class _CharT, class _Traits, class _Allocator>
1741inline _LIBCPP_INLINE_VISIBILITY
1742basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, size_type __pos,
1743                                                        const _Allocator& __a)
1744    : __r_(__second_tag(), __a)
1745{
1746    size_type __str_sz = __str.size();
1747    if (__pos > __str_sz)
1748        this->__throw_out_of_range();
1749    __init(__str.data() + __pos, __str_sz - __pos);
1750#if _LIBCPP_DEBUG_LEVEL >= 2
1751    __get_db()->__insert_c(this);
1752#endif
1753}
1754
1755template <class _CharT, class _Traits, class _Allocator>
1756template <class _Tp>
1757basic_string<_CharT, _Traits, _Allocator>::basic_string(
1758             const _Tp& __t, size_type __pos, size_type __n, const allocator_type& __a,
1759			 typename enable_if<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value, void>::type *)
1760    : __r_(__second_tag(), __a)
1761{
1762	__self_view __sv = __self_view(__t).substr(__pos, __n);
1763    __init(__sv.data(), __sv.size());
1764#if _LIBCPP_DEBUG_LEVEL >= 2
1765    __get_db()->__insert_c(this);
1766#endif
1767}
1768
1769template <class _CharT, class _Traits, class _Allocator>
1770inline _LIBCPP_INLINE_VISIBILITY
1771basic_string<_CharT, _Traits, _Allocator>::basic_string(__self_view __sv)
1772{
1773    __init(__sv.data(), __sv.size());
1774#if _LIBCPP_DEBUG_LEVEL >= 2
1775    __get_db()->__insert_c(this);
1776#endif
1777}
1778
1779template <class _CharT, class _Traits, class _Allocator>
1780inline _LIBCPP_INLINE_VISIBILITY
1781basic_string<_CharT, _Traits, _Allocator>::basic_string(__self_view __sv, const _Allocator& __a)
1782    : __r_(__second_tag(), __a)
1783{
1784    __init(__sv.data(), __sv.size());
1785#if _LIBCPP_DEBUG_LEVEL >= 2
1786    __get_db()->__insert_c(this);
1787#endif
1788}
1789
1790template <class _CharT, class _Traits, class _Allocator>
1791template <class _InputIterator>
1792typename enable_if
1793<
1794    __is_exactly_input_iterator<_InputIterator>::value,
1795    void
1796>::type
1797basic_string<_CharT, _Traits, _Allocator>::__init(_InputIterator __first, _InputIterator __last)
1798{
1799    __zero();
1800#ifndef _LIBCPP_NO_EXCEPTIONS
1801    try
1802    {
1803#endif  // _LIBCPP_NO_EXCEPTIONS
1804    for (; __first != __last; ++__first)
1805        push_back(*__first);
1806#ifndef _LIBCPP_NO_EXCEPTIONS
1807    }
1808    catch (...)
1809    {
1810        if (__is_long())
1811            __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
1812        throw;
1813    }
1814#endif  // _LIBCPP_NO_EXCEPTIONS
1815}
1816
1817template <class _CharT, class _Traits, class _Allocator>
1818template <class _ForwardIterator>
1819typename enable_if
1820<
1821    __is_forward_iterator<_ForwardIterator>::value,
1822    void
1823>::type
1824basic_string<_CharT, _Traits, _Allocator>::__init(_ForwardIterator __first, _ForwardIterator __last)
1825{
1826    size_type __sz = static_cast<size_type>(_VSTD::distance(__first, __last));
1827    if (__sz > max_size())
1828        this->__throw_length_error();
1829    pointer __p;
1830    if (__sz < __min_cap)
1831    {
1832        __set_short_size(__sz);
1833        __p = __get_short_pointer();
1834    }
1835    else
1836    {
1837        size_type __cap = __recommend(__sz);
1838        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1839        __set_long_pointer(__p);
1840        __set_long_cap(__cap+1);
1841        __set_long_size(__sz);
1842    }
1843    for (; __first != __last; ++__first, (void) ++__p)
1844        traits_type::assign(*__p, *__first);
1845    traits_type::assign(*__p, value_type());
1846}
1847
1848template <class _CharT, class _Traits, class _Allocator>
1849template<class _InputIterator>
1850inline _LIBCPP_INLINE_VISIBILITY
1851basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last)
1852{
1853    __init(__first, __last);
1854#if _LIBCPP_DEBUG_LEVEL >= 2
1855    __get_db()->__insert_c(this);
1856#endif
1857}
1858
1859template <class _CharT, class _Traits, class _Allocator>
1860template<class _InputIterator>
1861inline _LIBCPP_INLINE_VISIBILITY
1862basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last,
1863                                                        const allocator_type& __a)
1864    : __r_(__second_tag(), __a)
1865{
1866    __init(__first, __last);
1867#if _LIBCPP_DEBUG_LEVEL >= 2
1868    __get_db()->__insert_c(this);
1869#endif
1870}
1871
1872#ifndef _LIBCPP_CXX03_LANG
1873
1874template <class _CharT, class _Traits, class _Allocator>
1875inline _LIBCPP_INLINE_VISIBILITY
1876basic_string<_CharT, _Traits, _Allocator>::basic_string(
1877    initializer_list<_CharT> __il)
1878{
1879    __init(__il.begin(), __il.end());
1880#if _LIBCPP_DEBUG_LEVEL >= 2
1881    __get_db()->__insert_c(this);
1882#endif
1883}
1884
1885template <class _CharT, class _Traits, class _Allocator>
1886inline _LIBCPP_INLINE_VISIBILITY
1887
1888basic_string<_CharT, _Traits, _Allocator>::basic_string(
1889    initializer_list<_CharT> __il, const _Allocator& __a)
1890    : __r_(__second_tag(), __a)
1891{
1892    __init(__il.begin(), __il.end());
1893#if _LIBCPP_DEBUG_LEVEL >= 2
1894    __get_db()->__insert_c(this);
1895#endif
1896}
1897
1898#endif  // _LIBCPP_CXX03_LANG
1899
1900template <class _CharT, class _Traits, class _Allocator>
1901basic_string<_CharT, _Traits, _Allocator>::~basic_string()
1902{
1903#if _LIBCPP_DEBUG_LEVEL >= 2
1904    __get_db()->__erase_c(this);
1905#endif
1906    if (__is_long())
1907        __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
1908}
1909
1910template <class _CharT, class _Traits, class _Allocator>
1911void
1912basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace
1913    (size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1914     size_type __n_copy,  size_type __n_del,     size_type __n_add, const value_type* __p_new_stuff)
1915{
1916    size_type __ms = max_size();
1917    if (__delta_cap > __ms - __old_cap - 1)
1918        this->__throw_length_error();
1919    pointer __old_p = __get_pointer();
1920    size_type __cap = __old_cap < __ms / 2 - __alignment ?
1921                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
1922                          __ms - 1;
1923    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
1924    __invalidate_all_iterators();
1925    if (__n_copy != 0)
1926        traits_type::copy(_VSTD::__to_raw_pointer(__p),
1927                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
1928    if (__n_add != 0)
1929        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy, __p_new_stuff, __n_add);
1930    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
1931    if (__sec_cp_sz != 0)
1932        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
1933                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del, __sec_cp_sz);
1934    if (__old_cap+1 != __min_cap)
1935        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
1936    __set_long_pointer(__p);
1937    __set_long_cap(__cap+1);
1938    __old_sz = __n_copy + __n_add + __sec_cp_sz;
1939    __set_long_size(__old_sz);
1940    traits_type::assign(__p[__old_sz], value_type());
1941}
1942
1943template <class _CharT, class _Traits, class _Allocator>
1944void
1945basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1946                                                     size_type __n_copy,  size_type __n_del,     size_type __n_add)
1947{
1948    size_type __ms = max_size();
1949    if (__delta_cap > __ms - __old_cap)
1950        this->__throw_length_error();
1951    pointer __old_p = __get_pointer();
1952    size_type __cap = __old_cap < __ms / 2 - __alignment ?
1953                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
1954                          __ms - 1;
1955    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
1956    __invalidate_all_iterators();
1957    if (__n_copy != 0)
1958        traits_type::copy(_VSTD::__to_raw_pointer(__p),
1959                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
1960    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
1961    if (__sec_cp_sz != 0)
1962        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
1963                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del,
1964                          __sec_cp_sz);
1965    if (__old_cap+1 != __min_cap)
1966        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
1967    __set_long_pointer(__p);
1968    __set_long_cap(__cap+1);
1969}
1970
1971// assign
1972
1973template <class _CharT, class _Traits, class _Allocator>
1974basic_string<_CharT, _Traits, _Allocator>&
1975basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n)
1976{
1977    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::assign received nullptr");
1978    size_type __cap = capacity();
1979    if (__cap >= __n)
1980    {
1981        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
1982        traits_type::move(__p, __s, __n);
1983        traits_type::assign(__p[__n], value_type());
1984        __set_size(__n);
1985        __invalidate_iterators_past(__n);
1986    }
1987    else
1988    {
1989        size_type __sz = size();
1990        __grow_by_and_replace(__cap, __n - __cap, __sz, 0, __sz, __n, __s);
1991    }
1992    return *this;
1993}
1994
1995template <class _CharT, class _Traits, class _Allocator>
1996basic_string<_CharT, _Traits, _Allocator>&
1997basic_string<_CharT, _Traits, _Allocator>::assign(size_type __n, value_type __c)
1998{
1999    size_type __cap = capacity();
2000    if (__cap < __n)
2001    {
2002        size_type __sz = size();
2003        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
2004    }
2005    else
2006        __invalidate_iterators_past(__n);
2007    value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2008    traits_type::assign(__p, __n, __c);
2009    traits_type::assign(__p[__n], value_type());
2010    __set_size(__n);
2011    return *this;
2012}
2013
2014template <class _CharT, class _Traits, class _Allocator>
2015basic_string<_CharT, _Traits, _Allocator>&
2016basic_string<_CharT, _Traits, _Allocator>::operator=(value_type __c)
2017{
2018    pointer __p;
2019    if (__is_long())
2020    {
2021        __p = __get_long_pointer();
2022        __set_long_size(1);
2023    }
2024    else
2025    {
2026        __p = __get_short_pointer();
2027        __set_short_size(1);
2028    }
2029    traits_type::assign(*__p, __c);
2030    traits_type::assign(*++__p, value_type());
2031    __invalidate_iterators_past(1);
2032    return *this;
2033}
2034
2035template <class _CharT, class _Traits, class _Allocator>
2036basic_string<_CharT, _Traits, _Allocator>&
2037basic_string<_CharT, _Traits, _Allocator>::operator=(const basic_string& __str)
2038{
2039    if (this != &__str)
2040    {
2041        __copy_assign_alloc(__str);
2042        assign(__str.data(), __str.size());
2043    }
2044    return *this;
2045}
2046
2047#ifndef _LIBCPP_CXX03_LANG
2048
2049template <class _CharT, class _Traits, class _Allocator>
2050inline _LIBCPP_INLINE_VISIBILITY
2051void
2052basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, false_type)
2053    _NOEXCEPT_(__alloc_traits::is_always_equal::value)
2054{
2055    if (__alloc() != __str.__alloc())
2056        assign(__str);
2057    else
2058        __move_assign(__str, true_type());
2059}
2060
2061template <class _CharT, class _Traits, class _Allocator>
2062inline _LIBCPP_INLINE_VISIBILITY
2063void
2064basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, true_type)
2065#if _LIBCPP_STD_VER > 14
2066    _NOEXCEPT
2067#else
2068    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
2069#endif
2070{
2071    clear();
2072    shrink_to_fit();
2073    __r_.first() = __str.__r_.first();
2074    __move_assign_alloc(__str);
2075    __str.__zero();
2076}
2077
2078template <class _CharT, class _Traits, class _Allocator>
2079inline _LIBCPP_INLINE_VISIBILITY
2080basic_string<_CharT, _Traits, _Allocator>&
2081basic_string<_CharT, _Traits, _Allocator>::operator=(basic_string&& __str)
2082    _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value))
2083{
2084    __move_assign(__str, integral_constant<bool,
2085          __alloc_traits::propagate_on_container_move_assignment::value>());
2086    return *this;
2087}
2088
2089#endif
2090
2091template <class _CharT, class _Traits, class _Allocator>
2092template<class _InputIterator>
2093typename enable_if
2094<
2095     __is_exactly_input_iterator <_InputIterator>::value
2096          || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
2097    basic_string<_CharT, _Traits, _Allocator>&
2098>::type
2099basic_string<_CharT, _Traits, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
2100{
2101    const basic_string __temp(__first, __last, __alloc());
2102    assign(__temp.data(), __temp.size());
2103    return *this;
2104}
2105
2106template <class _CharT, class _Traits, class _Allocator>
2107template<class _ForwardIterator>
2108typename enable_if
2109<
2110    __is_forward_iterator<_ForwardIterator>::value
2111         && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
2112    basic_string<_CharT, _Traits, _Allocator>&
2113>::type
2114basic_string<_CharT, _Traits, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last)
2115{
2116    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2117    size_type __cap = capacity();
2118    if (__cap < __n)
2119    {
2120        size_type __sz = size();
2121        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
2122    }
2123    else
2124        __invalidate_iterators_past(__n);
2125    pointer __p = __get_pointer();
2126    for (; __first != __last; ++__first, ++__p)
2127        traits_type::assign(*__p, *__first);
2128    traits_type::assign(*__p, value_type());
2129    __set_size(__n);
2130    return *this;
2131}
2132
2133template <class _CharT, class _Traits, class _Allocator>
2134basic_string<_CharT, _Traits, _Allocator>&
2135basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str, size_type __pos, size_type __n)
2136{
2137    size_type __sz = __str.size();
2138    if (__pos > __sz)
2139        this->__throw_out_of_range();
2140    return assign(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2141}
2142
2143template <class _CharT, class _Traits, class _Allocator>
2144template <class _Tp>
2145typename enable_if
2146<
2147    __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2148	basic_string<_CharT, _Traits, _Allocator>&
2149>::type
2150basic_string<_CharT, _Traits, _Allocator>::assign(const _Tp & __t, size_type __pos, size_type __n)
2151{
2152    __self_view __sv = __t;
2153    size_type __sz = __sv.size();
2154    if (__pos > __sz)
2155        this->__throw_out_of_range();
2156    return assign(__sv.data() + __pos, _VSTD::min(__n, __sz - __pos));
2157}
2158
2159
2160template <class _CharT, class _Traits, class _Allocator>
2161basic_string<_CharT, _Traits, _Allocator>&
2162basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s)
2163{
2164    _LIBCPP_ASSERT(__s != nullptr, "string::assign received nullptr");
2165    return assign(__s, traits_type::length(__s));
2166}
2167
2168// append
2169
2170template <class _CharT, class _Traits, class _Allocator>
2171basic_string<_CharT, _Traits, _Allocator>&
2172basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s, size_type __n)
2173{
2174    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::append received nullptr");
2175    size_type __cap = capacity();
2176    size_type __sz = size();
2177    if (__cap - __sz >= __n)
2178    {
2179        if (__n)
2180        {
2181            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2182            traits_type::copy(__p + __sz, __s, __n);
2183            __sz += __n;
2184            __set_size(__sz);
2185            traits_type::assign(__p[__sz], value_type());
2186        }
2187    }
2188    else
2189        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __sz, 0, __n, __s);
2190    return *this;
2191}
2192
2193template <class _CharT, class _Traits, class _Allocator>
2194basic_string<_CharT, _Traits, _Allocator>&
2195basic_string<_CharT, _Traits, _Allocator>::append(size_type __n, value_type __c)
2196{
2197    if (__n)
2198    {
2199        size_type __cap = capacity();
2200        size_type __sz = size();
2201        if (__cap - __sz < __n)
2202            __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2203        pointer __p = __get_pointer();
2204        traits_type::assign(_VSTD::__to_raw_pointer(__p) + __sz, __n, __c);
2205        __sz += __n;
2206        __set_size(__sz);
2207        traits_type::assign(__p[__sz], value_type());
2208    }
2209    return *this;
2210}
2211
2212template <class _CharT, class _Traits, class _Allocator>
2213void
2214basic_string<_CharT, _Traits, _Allocator>::push_back(value_type __c)
2215{
2216    bool __is_short = !__is_long();
2217    size_type __cap;
2218    size_type __sz;
2219    if (__is_short)
2220    {
2221        __cap = __min_cap - 1;
2222        __sz = __get_short_size();
2223    }
2224    else
2225    {
2226        __cap = __get_long_cap() - 1;
2227        __sz = __get_long_size();
2228    }
2229    if (__sz == __cap)
2230    {
2231        __grow_by(__cap, 1, __sz, __sz, 0);
2232        __is_short = !__is_long();
2233    }
2234    pointer __p;
2235    if (__is_short)
2236    {
2237        __p = __get_short_pointer() + __sz;
2238        __set_short_size(__sz+1);
2239    }
2240    else
2241    {
2242        __p = __get_long_pointer() + __sz;
2243        __set_long_size(__sz+1);
2244    }
2245    traits_type::assign(*__p, __c);
2246    traits_type::assign(*++__p, value_type());
2247}
2248
2249template <class _Tp>
2250bool __ptr_in_range (const _Tp* __p, const _Tp* __first, const _Tp* __last)
2251{
2252    return __first <= __p && __p < __last;
2253}
2254
2255template <class _Tp1, class _Tp2>
2256bool __ptr_in_range (const _Tp1*, const _Tp2*, const _Tp2*)
2257{
2258    return false;
2259}
2260
2261template <class _CharT, class _Traits, class _Allocator>
2262template<class _ForwardIterator>
2263basic_string<_CharT, _Traits, _Allocator>&
2264basic_string<_CharT, _Traits, _Allocator>::__append_forward_unsafe(
2265    _ForwardIterator __first, _ForwardIterator __last)
2266{
2267    static_assert(__is_forward_iterator<_ForwardIterator>::value,
2268                  "function requires a ForwardIterator");
2269    size_type __sz = size();
2270    size_type __cap = capacity();
2271    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2272    if (__n)
2273    {
2274        typedef typename iterator_traits<_ForwardIterator>::reference _CharRef;
2275        _CharRef __tmp_ref = *__first;
2276        if (__ptr_in_range(_VSTD::addressof(__tmp_ref), data(), data() + size()))
2277        {
2278            const basic_string __temp (__first, __last, __alloc());
2279            append(__temp.data(), __temp.size());
2280        }
2281        else 
2282        {
2283            if (__cap - __sz < __n)
2284                __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2285            pointer __p = __get_pointer() + __sz;
2286            for (; __first != __last; ++__p, ++__first)
2287                traits_type::assign(*__p, *__first);
2288            traits_type::assign(*__p, value_type());
2289            __set_size(__sz + __n);
2290        }
2291    }
2292    return *this;
2293}
2294
2295template <class _CharT, class _Traits, class _Allocator>
2296inline _LIBCPP_INLINE_VISIBILITY
2297basic_string<_CharT, _Traits, _Allocator>&
2298basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str)
2299{
2300    return append(__str.data(), __str.size());
2301}
2302
2303template <class _CharT, class _Traits, class _Allocator>
2304basic_string<_CharT, _Traits, _Allocator>&
2305basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str, size_type __pos, size_type __n)
2306{
2307    size_type __sz = __str.size();
2308    if (__pos > __sz)
2309        this->__throw_out_of_range();
2310    return append(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2311}
2312
2313template <class _CharT, class _Traits, class _Allocator>
2314template <class _Tp>
2315    typename enable_if
2316    <
2317        __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2318        basic_string<_CharT, _Traits, _Allocator>&
2319    >::type
2320basic_string<_CharT, _Traits, _Allocator>::append(const _Tp & __t, size_type __pos, size_type __n)
2321{
2322    __self_view __sv = __t;
2323    size_type __sz = __sv.size();
2324    if (__pos > __sz)
2325        this->__throw_out_of_range();
2326    return append(__sv.data() + __pos, _VSTD::min(__n, __sz - __pos));
2327}
2328
2329template <class _CharT, class _Traits, class _Allocator>
2330basic_string<_CharT, _Traits, _Allocator>&
2331basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s)
2332{
2333    _LIBCPP_ASSERT(__s != nullptr, "string::append received nullptr");
2334    return append(__s, traits_type::length(__s));
2335}
2336
2337// insert
2338
2339template <class _CharT, class _Traits, class _Allocator>
2340basic_string<_CharT, _Traits, _Allocator>&
2341basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s, size_type __n)
2342{
2343    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::insert received nullptr");
2344    size_type __sz = size();
2345    if (__pos > __sz)
2346        this->__throw_out_of_range();
2347    size_type __cap = capacity();
2348    if (__cap - __sz >= __n)
2349    {
2350        if (__n)
2351        {
2352            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2353            size_type __n_move = __sz - __pos;
2354            if (__n_move != 0)
2355            {
2356                if (__p + __pos <= __s && __s < __p + __sz)
2357                    __s += __n;
2358                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2359            }
2360            traits_type::move(__p + __pos, __s, __n);
2361            __sz += __n;
2362            __set_size(__sz);
2363            traits_type::assign(__p[__sz], value_type());
2364        }
2365    }
2366    else
2367        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __pos, 0, __n, __s);
2368    return *this;
2369}
2370
2371template <class _CharT, class _Traits, class _Allocator>
2372basic_string<_CharT, _Traits, _Allocator>&
2373basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n, value_type __c)
2374{
2375    size_type __sz = size();
2376    if (__pos > __sz)
2377        this->__throw_out_of_range();
2378    if (__n)
2379    {
2380        size_type __cap = capacity();
2381        value_type* __p;
2382        if (__cap - __sz >= __n)
2383        {
2384            __p = _VSTD::__to_raw_pointer(__get_pointer());
2385            size_type __n_move = __sz - __pos;
2386            if (__n_move != 0)
2387                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2388        }
2389        else
2390        {
2391            __grow_by(__cap, __sz + __n - __cap, __sz, __pos, 0, __n);
2392            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2393        }
2394        traits_type::assign(__p + __pos, __n, __c);
2395        __sz += __n;
2396        __set_size(__sz);
2397        traits_type::assign(__p[__sz], value_type());
2398    }
2399    return *this;
2400}
2401
2402template <class _CharT, class _Traits, class _Allocator>
2403template<class _InputIterator>
2404typename enable_if
2405<
2406   __is_exactly_input_iterator<_InputIterator>::value
2407        || !__libcpp_string_gets_noexcept_iterator<_InputIterator>::value,
2408   typename basic_string<_CharT, _Traits, _Allocator>::iterator
2409>::type
2410basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _InputIterator __first, _InputIterator __last)
2411{
2412#if _LIBCPP_DEBUG_LEVEL >= 2
2413    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2414        "string::insert(iterator, range) called with an iterator not"
2415        " referring to this string");
2416#endif
2417    const basic_string __temp(__first, __last, __alloc());
2418    return insert(__pos, __temp.data(), __temp.data() + __temp.size());
2419}
2420
2421template <class _CharT, class _Traits, class _Allocator>
2422template<class _ForwardIterator>
2423typename enable_if
2424<
2425    __is_forward_iterator<_ForwardIterator>::value
2426        && __libcpp_string_gets_noexcept_iterator<_ForwardIterator>::value,
2427    typename basic_string<_CharT, _Traits, _Allocator>::iterator
2428>::type
2429basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last)
2430{
2431#if _LIBCPP_DEBUG_LEVEL >= 2
2432    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2433        "string::insert(iterator, range) called with an iterator not"
2434        " referring to this string");
2435#endif
2436    size_type __ip = static_cast<size_type>(__pos - begin());
2437    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2438    if (__n)
2439    {
2440        typedef typename iterator_traits<_ForwardIterator>::reference _CharRef;
2441        _CharRef __tmp_char = *__first;
2442        if (__ptr_in_range(_VSTD::addressof(__tmp_char), data(), data() + size()))
2443        {
2444            const basic_string __temp(__first, __last, __alloc());
2445            return insert(__pos, __temp.data(), __temp.data() + __temp.size());
2446        }
2447
2448        size_type __sz = size();
2449        size_type __cap = capacity();
2450        value_type* __p;
2451        if (__cap - __sz >= __n)
2452        {
2453            __p = _VSTD::__to_raw_pointer(__get_pointer());
2454            size_type __n_move = __sz - __ip;
2455            if (__n_move != 0)
2456                traits_type::move(__p + __ip + __n, __p + __ip, __n_move);
2457        }
2458        else
2459        {
2460            __grow_by(__cap, __sz + __n - __cap, __sz, __ip, 0, __n);
2461            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2462        }
2463        __sz += __n;
2464        __set_size(__sz);
2465        traits_type::assign(__p[__sz], value_type());
2466        for (__p += __ip; __first != __last; ++__p, ++__first)
2467            traits_type::assign(*__p, *__first);
2468    }
2469    return begin() + __ip;
2470}
2471
2472template <class _CharT, class _Traits, class _Allocator>
2473inline _LIBCPP_INLINE_VISIBILITY
2474basic_string<_CharT, _Traits, _Allocator>&
2475basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str)
2476{
2477    return insert(__pos1, __str.data(), __str.size());
2478}
2479
2480template <class _CharT, class _Traits, class _Allocator>
2481basic_string<_CharT, _Traits, _Allocator>&
2482basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str,
2483                                                  size_type __pos2, size_type __n)
2484{
2485    size_type __str_sz = __str.size();
2486    if (__pos2 > __str_sz)
2487        this->__throw_out_of_range();
2488    return insert(__pos1, __str.data() + __pos2, _VSTD::min(__n, __str_sz - __pos2));
2489}
2490
2491template <class _CharT, class _Traits, class _Allocator>
2492template <class _Tp>
2493typename enable_if
2494<
2495    __can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2496	basic_string<_CharT, _Traits, _Allocator>&
2497>::type
2498basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const _Tp& __t,
2499                                                  size_type __pos2, size_type __n)
2500{
2501    __self_view __sv = __t;
2502    size_type __str_sz = __sv.size();
2503    if (__pos2 > __str_sz)
2504        this->__throw_out_of_range();
2505    return insert(__pos1, __sv.data() + __pos2, _VSTD::min(__n, __str_sz - __pos2));
2506}
2507
2508template <class _CharT, class _Traits, class _Allocator>
2509basic_string<_CharT, _Traits, _Allocator>&
2510basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s)
2511{
2512    _LIBCPP_ASSERT(__s != nullptr, "string::insert received nullptr");
2513    return insert(__pos, __s, traits_type::length(__s));
2514}
2515
2516template <class _CharT, class _Traits, class _Allocator>
2517typename basic_string<_CharT, _Traits, _Allocator>::iterator
2518basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_type __c)
2519{
2520    size_type __ip = static_cast<size_type>(__pos - begin());
2521    size_type __sz = size();
2522    size_type __cap = capacity();
2523    value_type* __p;
2524    if (__cap == __sz)
2525    {
2526        __grow_by(__cap, 1, __sz, __ip, 0, 1);
2527        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2528    }
2529    else
2530    {
2531        __p = _VSTD::__to_raw_pointer(__get_pointer());
2532        size_type __n_move = __sz - __ip;
2533        if (__n_move != 0)
2534            traits_type::move(__p + __ip + 1, __p + __ip, __n_move);
2535    }
2536    traits_type::assign(__p[__ip], __c);
2537    traits_type::assign(__p[++__sz], value_type());
2538    __set_size(__sz);
2539    return begin() + static_cast<difference_type>(__ip);
2540}
2541
2542template <class _CharT, class _Traits, class _Allocator>
2543inline _LIBCPP_INLINE_VISIBILITY
2544typename basic_string<_CharT, _Traits, _Allocator>::iterator
2545basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, size_type __n, value_type __c)
2546{
2547#if _LIBCPP_DEBUG_LEVEL >= 2
2548    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2549        "string::insert(iterator, n, value) called with an iterator not"
2550        " referring to this string");
2551#endif
2552    difference_type __p = __pos - begin();
2553    insert(static_cast<size_type>(__p), __n, __c);
2554    return begin() + __p;
2555}
2556
2557// replace
2558
2559template <class _CharT, class _Traits, class _Allocator>
2560basic_string<_CharT, _Traits, _Allocator>&
2561basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2)
2562    _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
2563{
2564    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::replace received nullptr");
2565    size_type __sz = size();
2566    if (__pos > __sz)
2567        this->__throw_out_of_range();
2568    __n1 = _VSTD::min(__n1, __sz - __pos);
2569    size_type __cap = capacity();
2570    if (__cap - __sz + __n1 >= __n2)
2571    {
2572        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2573        if (__n1 != __n2)
2574        {
2575            size_type __n_move = __sz - __pos - __n1;
2576            if (__n_move != 0)
2577            {
2578                if (__n1 > __n2)
2579                {
2580                    traits_type::move(__p + __pos, __s, __n2);
2581                    traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2582                    goto __finish;
2583                }
2584                if (__p + __pos < __s && __s < __p + __sz)
2585                {
2586                    if (__p + __pos + __n1 <= __s)
2587                        __s += __n2 - __n1;
2588                    else // __p + __pos < __s < __p + __pos + __n1
2589                    {
2590                        traits_type::move(__p + __pos, __s, __n1);
2591                        __pos += __n1;
2592                        __s += __n2;
2593                        __n2 -= __n1;
2594                        __n1 = 0;
2595                    }
2596                }
2597                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2598            }
2599        }
2600        traits_type::move(__p + __pos, __s, __n2);
2601__finish:
2602// __sz += __n2 - __n1; in this and the below function below can cause unsigned integer overflow,
2603// but this is a safe operation, so we disable the check.
2604        __sz += __n2 - __n1;
2605        __set_size(__sz);
2606        __invalidate_iterators_past(__sz);
2607        traits_type::assign(__p[__sz], value_type());
2608    }
2609    else
2610        __grow_by_and_replace(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2, __s);
2611    return *this;
2612}
2613
2614template <class _CharT, class _Traits, class _Allocator>
2615basic_string<_CharT, _Traits, _Allocator>&
2616basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, size_type __n2, value_type __c)
2617    _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
2618{
2619    size_type __sz = size();
2620    if (__pos > __sz)
2621        this->__throw_out_of_range();
2622    __n1 = _VSTD::min(__n1, __sz - __pos);
2623    size_type __cap = capacity();
2624    value_type* __p;
2625    if (__cap - __sz + __n1 >= __n2)
2626    {
2627        __p = _VSTD::__to_raw_pointer(__get_pointer());
2628        if (__n1 != __n2)
2629        {
2630            size_type __n_move = __sz - __pos - __n1;
2631            if (__n_move != 0)
2632                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2633        }
2634    }
2635    else
2636    {
2637        __grow_by(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2);
2638        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2639    }
2640    traits_type::assign(__p + __pos, __n2, __c);
2641    __sz += __n2 - __n1;
2642    __set_size(__sz);
2643    __invalidate_iterators_past(__sz);
2644    traits_type::assign(__p[__sz], value_type());
2645    return *this;
2646}
2647
2648template <class _CharT, class _Traits, class _Allocator>
2649template<class _InputIterator>
2650typename enable_if
2651<
2652    __is_input_iterator<_InputIterator>::value,
2653    basic_string<_CharT, _Traits, _Allocator>&
2654>::type
2655basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2,
2656                                                   _InputIterator __j1, _InputIterator __j2)
2657{
2658    const basic_string __temp(__j1, __j2, __alloc());
2659    return this->replace(__i1, __i2, __temp);
2660}
2661
2662template <class _CharT, class _Traits, class _Allocator>
2663inline _LIBCPP_INLINE_VISIBILITY
2664basic_string<_CharT, _Traits, _Allocator>&
2665basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str)
2666{
2667    return replace(__pos1, __n1, __str.data(), __str.size());
2668}
2669
2670template <class _CharT, class _Traits, class _Allocator>
2671basic_string<_CharT, _Traits, _Allocator>&
2672basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str,
2673                                                   size_type __pos2, size_type __n2)
2674{
2675    size_type __str_sz = __str.size();
2676    if (__pos2 > __str_sz)
2677        this->__throw_out_of_range();
2678    return replace(__pos1, __n1, __str.data() + __pos2, _VSTD::min(__n2, __str_sz - __pos2));
2679}
2680
2681template <class _CharT, class _Traits, class _Allocator>
2682template <class _Tp>
2683typename enable_if
2684<
2685	__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
2686	basic_string<_CharT, _Traits, _Allocator>&
2687>::type
2688basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const _Tp& __t,
2689                                                   size_type __pos2, size_type __n2)
2690{
2691    __self_view __sv = __t;
2692    size_type __str_sz = __sv.size();
2693    if (__pos2 > __str_sz)
2694        this->__throw_out_of_range();
2695    return replace(__pos1, __n1, __sv.data() + __pos2, _VSTD::min(__n2, __str_sz - __pos2));
2696}
2697
2698template <class _CharT, class _Traits, class _Allocator>
2699basic_string<_CharT, _Traits, _Allocator>&
2700basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s)
2701{
2702    _LIBCPP_ASSERT(__s != nullptr, "string::replace received nullptr");
2703    return replace(__pos, __n1, __s, traits_type::length(__s));
2704}
2705
2706template <class _CharT, class _Traits, class _Allocator>
2707inline _LIBCPP_INLINE_VISIBILITY
2708basic_string<_CharT, _Traits, _Allocator>&
2709basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const basic_string& __str)
2710{
2711    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1),
2712                   __str.data(), __str.size());
2713}
2714
2715template <class _CharT, class _Traits, class _Allocator>
2716inline _LIBCPP_INLINE_VISIBILITY
2717basic_string<_CharT, _Traits, _Allocator>&
2718basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n)
2719{
2720    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s, __n);
2721}
2722
2723template <class _CharT, class _Traits, class _Allocator>
2724inline _LIBCPP_INLINE_VISIBILITY
2725basic_string<_CharT, _Traits, _Allocator>&
2726basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s)
2727{
2728    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s);
2729}
2730
2731template <class _CharT, class _Traits, class _Allocator>
2732inline _LIBCPP_INLINE_VISIBILITY
2733basic_string<_CharT, _Traits, _Allocator>&
2734basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c)
2735{
2736    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __n, __c);
2737}
2738
2739// erase
2740
2741template <class _CharT, class _Traits, class _Allocator>
2742basic_string<_CharT, _Traits, _Allocator>&
2743basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos, size_type __n)
2744{
2745    size_type __sz = size();
2746    if (__pos > __sz)
2747        this->__throw_out_of_range();
2748    if (__n)
2749    {
2750        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2751        __n = _VSTD::min(__n, __sz - __pos);
2752        size_type __n_move = __sz - __pos - __n;
2753        if (__n_move != 0)
2754            traits_type::move(__p + __pos, __p + __pos + __n, __n_move);
2755        __sz -= __n;
2756        __set_size(__sz);
2757        __invalidate_iterators_past(__sz);
2758        traits_type::assign(__p[__sz], value_type());
2759    }
2760    return *this;
2761}
2762
2763template <class _CharT, class _Traits, class _Allocator>
2764inline _LIBCPP_INLINE_VISIBILITY
2765typename basic_string<_CharT, _Traits, _Allocator>::iterator
2766basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __pos)
2767{
2768#if _LIBCPP_DEBUG_LEVEL >= 2
2769    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2770        "string::erase(iterator) called with an iterator not"
2771        " referring to this string");
2772#endif
2773    _LIBCPP_ASSERT(__pos != end(),
2774        "string::erase(iterator) called with a non-dereferenceable iterator");
2775    iterator __b = begin();
2776    size_type __r = static_cast<size_type>(__pos - __b);
2777    erase(__r, 1);
2778    return __b + static_cast<difference_type>(__r);
2779}
2780
2781template <class _CharT, class _Traits, class _Allocator>
2782inline _LIBCPP_INLINE_VISIBILITY
2783typename basic_string<_CharT, _Traits, _Allocator>::iterator
2784basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __first, const_iterator __last)
2785{
2786#if _LIBCPP_DEBUG_LEVEL >= 2
2787    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
2788        "string::erase(iterator,  iterator) called with an iterator not"
2789        " referring to this string");
2790#endif
2791    _LIBCPP_ASSERT(__first <= __last, "string::erase(first, last) called with invalid range");
2792    iterator __b = begin();
2793    size_type __r = static_cast<size_type>(__first - __b);
2794    erase(__r, static_cast<size_type>(__last - __first));
2795    return __b + static_cast<difference_type>(__r);
2796}
2797
2798template <class _CharT, class _Traits, class _Allocator>
2799inline _LIBCPP_INLINE_VISIBILITY
2800void
2801basic_string<_CharT, _Traits, _Allocator>::pop_back()
2802{
2803    _LIBCPP_ASSERT(!empty(), "string::pop_back(): string is already empty");
2804    size_type __sz;
2805    if (__is_long())
2806    {
2807        __sz = __get_long_size() - 1;
2808        __set_long_size(__sz);
2809        traits_type::assign(*(__get_long_pointer() + __sz), value_type());
2810    }
2811    else
2812    {
2813        __sz = __get_short_size() - 1;
2814        __set_short_size(__sz);
2815        traits_type::assign(*(__get_short_pointer() + __sz), value_type());
2816    }
2817    __invalidate_iterators_past(__sz);
2818}
2819
2820template <class _CharT, class _Traits, class _Allocator>
2821inline _LIBCPP_INLINE_VISIBILITY
2822void
2823basic_string<_CharT, _Traits, _Allocator>::clear() _NOEXCEPT
2824{
2825    __invalidate_all_iterators();
2826    if (__is_long())
2827    {
2828        traits_type::assign(*__get_long_pointer(), value_type());
2829        __set_long_size(0);
2830    }
2831    else
2832    {
2833        traits_type::assign(*__get_short_pointer(), value_type());
2834        __set_short_size(0);
2835    }
2836}
2837
2838template <class _CharT, class _Traits, class _Allocator>
2839inline _LIBCPP_INLINE_VISIBILITY
2840void
2841basic_string<_CharT, _Traits, _Allocator>::__erase_to_end(size_type __pos)
2842{
2843    if (__is_long())
2844    {
2845        traits_type::assign(*(__get_long_pointer() + __pos), value_type());
2846        __set_long_size(__pos);
2847    }
2848    else
2849    {
2850        traits_type::assign(*(__get_short_pointer() + __pos), value_type());
2851        __set_short_size(__pos);
2852    }
2853    __invalidate_iterators_past(__pos);
2854}
2855
2856template <class _CharT, class _Traits, class _Allocator>
2857void
2858basic_string<_CharT, _Traits, _Allocator>::resize(size_type __n, value_type __c)
2859{
2860    size_type __sz = size();
2861    if (__n > __sz)
2862        append(__n - __sz, __c);
2863    else
2864        __erase_to_end(__n);
2865}
2866
2867template <class _CharT, class _Traits, class _Allocator>
2868inline _LIBCPP_INLINE_VISIBILITY
2869typename basic_string<_CharT, _Traits, _Allocator>::size_type
2870basic_string<_CharT, _Traits, _Allocator>::max_size() const _NOEXCEPT
2871{
2872    size_type __m = __alloc_traits::max_size(__alloc());
2873#ifdef _LIBCPP_BIG_ENDIAN
2874    return (__m <= ~__long_mask ? __m : __m/2) - __alignment;
2875#else
2876    return __m - __alignment;
2877#endif
2878}
2879
2880template <class _CharT, class _Traits, class _Allocator>
2881void
2882basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __res_arg)
2883{
2884    if (__res_arg > max_size())
2885        this->__throw_length_error();
2886    size_type __cap = capacity();
2887    size_type __sz = size();
2888    __res_arg = _VSTD::max(__res_arg, __sz);
2889    __res_arg = __recommend(__res_arg);
2890    if (__res_arg != __cap)
2891    {
2892        pointer __new_data, __p;
2893        bool __was_long, __now_long;
2894        if (__res_arg == __min_cap - 1)
2895        {
2896            __was_long = true;
2897            __now_long = false;
2898            __new_data = __get_short_pointer();
2899            __p = __get_long_pointer();
2900        }
2901        else
2902        {
2903            if (__res_arg > __cap)
2904                __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
2905            else
2906            {
2907            #ifndef _LIBCPP_NO_EXCEPTIONS
2908                try
2909                {
2910            #endif  // _LIBCPP_NO_EXCEPTIONS
2911                    __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
2912            #ifndef _LIBCPP_NO_EXCEPTIONS
2913                }
2914                catch (...)
2915                {
2916                    return;
2917                }
2918            #else  // _LIBCPP_NO_EXCEPTIONS
2919                if (__new_data == nullptr)
2920                    return;
2921            #endif  // _LIBCPP_NO_EXCEPTIONS
2922            }
2923            __now_long = true;
2924            __was_long = __is_long();
2925            __p = __get_pointer();
2926        }
2927        traits_type::copy(_VSTD::__to_raw_pointer(__new_data),
2928                          _VSTD::__to_raw_pointer(__p), size()+1);
2929        if (__was_long)
2930            __alloc_traits::deallocate(__alloc(), __p, __cap+1);
2931        if (__now_long)
2932        {
2933            __set_long_cap(__res_arg+1);
2934            __set_long_size(__sz);
2935            __set_long_pointer(__new_data);
2936        }
2937        else
2938            __set_short_size(__sz);
2939        __invalidate_all_iterators();
2940    }
2941}
2942
2943template <class _CharT, class _Traits, class _Allocator>
2944inline _LIBCPP_INLINE_VISIBILITY
2945typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2946basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos) const _NOEXCEPT
2947{
2948    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
2949    return *(data() + __pos);
2950}
2951
2952template <class _CharT, class _Traits, class _Allocator>
2953inline _LIBCPP_INLINE_VISIBILITY
2954typename basic_string<_CharT, _Traits, _Allocator>::reference
2955basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos) _NOEXCEPT
2956{
2957    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
2958    return *(__get_pointer() + __pos);
2959}
2960
2961template <class _CharT, class _Traits, class _Allocator>
2962typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2963basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) const
2964{
2965    if (__n >= size())
2966        this->__throw_out_of_range();
2967    return (*this)[__n];
2968}
2969
2970template <class _CharT, class _Traits, class _Allocator>
2971typename basic_string<_CharT, _Traits, _Allocator>::reference
2972basic_string<_CharT, _Traits, _Allocator>::at(size_type __n)
2973{
2974    if (__n >= size())
2975        this->__throw_out_of_range();
2976    return (*this)[__n];
2977}
2978
2979template <class _CharT, class _Traits, class _Allocator>
2980inline _LIBCPP_INLINE_VISIBILITY
2981typename basic_string<_CharT, _Traits, _Allocator>::reference
2982basic_string<_CharT, _Traits, _Allocator>::front()
2983{
2984    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
2985    return *__get_pointer();
2986}
2987
2988template <class _CharT, class _Traits, class _Allocator>
2989inline _LIBCPP_INLINE_VISIBILITY
2990typename basic_string<_CharT, _Traits, _Allocator>::const_reference
2991basic_string<_CharT, _Traits, _Allocator>::front() const
2992{
2993    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
2994    return *data();
2995}
2996
2997template <class _CharT, class _Traits, class _Allocator>
2998inline _LIBCPP_INLINE_VISIBILITY
2999typename basic_string<_CharT, _Traits, _Allocator>::reference
3000basic_string<_CharT, _Traits, _Allocator>::back()
3001{
3002    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
3003    return *(__get_pointer() + size() - 1);
3004}
3005
3006template <class _CharT, class _Traits, class _Allocator>
3007inline _LIBCPP_INLINE_VISIBILITY
3008typename basic_string<_CharT, _Traits, _Allocator>::const_reference
3009basic_string<_CharT, _Traits, _Allocator>::back() const
3010{
3011    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
3012    return *(data() + size() - 1);
3013}
3014
3015template <class _CharT, class _Traits, class _Allocator>
3016typename basic_string<_CharT, _Traits, _Allocator>::size_type
3017basic_string<_CharT, _Traits, _Allocator>::copy(value_type* __s, size_type __n, size_type __pos) const
3018{
3019    size_type __sz = size();
3020    if (__pos > __sz)
3021        this->__throw_out_of_range();
3022    size_type __rlen = _VSTD::min(__n, __sz - __pos);
3023    traits_type::copy(__s, data() + __pos, __rlen);
3024    return __rlen;
3025}
3026
3027template <class _CharT, class _Traits, class _Allocator>
3028inline _LIBCPP_INLINE_VISIBILITY
3029basic_string<_CharT, _Traits, _Allocator>
3030basic_string<_CharT, _Traits, _Allocator>::substr(size_type __pos, size_type __n) const
3031{
3032    return basic_string(*this, __pos, __n, __alloc());
3033}
3034
3035template <class _CharT, class _Traits, class _Allocator>
3036inline _LIBCPP_INLINE_VISIBILITY
3037void
3038basic_string<_CharT, _Traits, _Allocator>::swap(basic_string& __str)
3039#if _LIBCPP_STD_VER >= 14
3040        _NOEXCEPT_DEBUG
3041#else
3042        _NOEXCEPT_DEBUG_(!__alloc_traits::propagate_on_container_swap::value ||
3043                    __is_nothrow_swappable<allocator_type>::value)
3044#endif
3045{
3046#if _LIBCPP_DEBUG_LEVEL >= 2
3047    if (!__is_long())
3048        __get_db()->__invalidate_all(this);
3049    if (!__str.__is_long())
3050        __get_db()->__invalidate_all(&__str);
3051    __get_db()->swap(this, &__str);
3052#endif
3053    _LIBCPP_ASSERT(
3054        __alloc_traits::propagate_on_container_swap::value ||
3055        __alloc_traits::is_always_equal::value ||
3056        __alloc() == __str.__alloc(), "swapping non-equal allocators");
3057    _VSTD::swap(__r_.first(), __str.__r_.first());
3058    __swap_allocator(__alloc(), __str.__alloc());
3059}
3060
3061// find
3062
3063template <class _Traits>
3064struct _LIBCPP_HIDDEN __traits_eq
3065{
3066    typedef typename _Traits::char_type char_type;
3067    _LIBCPP_INLINE_VISIBILITY
3068    bool operator()(const char_type& __x, const char_type& __y) _NOEXCEPT
3069        {return _Traits::eq(__x, __y);}
3070};
3071
3072template<class _CharT, class _Traits, class _Allocator>
3073typename basic_string<_CharT, _Traits, _Allocator>::size_type
3074basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3075                                                size_type __pos,
3076                                                size_type __n) const _NOEXCEPT
3077{
3078    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find(): received nullptr");
3079    return __str_find<value_type, size_type, traits_type, npos>
3080        (data(), size(), __s, __pos, __n);
3081}
3082
3083template<class _CharT, class _Traits, class _Allocator>
3084inline _LIBCPP_INLINE_VISIBILITY
3085typename basic_string<_CharT, _Traits, _Allocator>::size_type
3086basic_string<_CharT, _Traits, _Allocator>::find(const basic_string& __str,
3087                                                size_type __pos) const _NOEXCEPT
3088{
3089    return __str_find<value_type, size_type, traits_type, npos>
3090        (data(), size(), __str.data(), __pos, __str.size());
3091}
3092
3093template<class _CharT, class _Traits, class _Allocator>
3094inline _LIBCPP_INLINE_VISIBILITY
3095typename basic_string<_CharT, _Traits, _Allocator>::size_type
3096basic_string<_CharT, _Traits, _Allocator>::find(__self_view __sv,
3097                                                size_type __pos) const _NOEXCEPT
3098{
3099    return __str_find<value_type, size_type, traits_type, npos>
3100        (data(), size(), __sv.data(), __pos, __sv.size());
3101}
3102
3103template<class _CharT, class _Traits, class _Allocator>
3104inline _LIBCPP_INLINE_VISIBILITY
3105typename basic_string<_CharT, _Traits, _Allocator>::size_type
3106basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3107                                                size_type __pos) const _NOEXCEPT
3108{
3109    _LIBCPP_ASSERT(__s != nullptr, "string::find(): received nullptr");
3110    return __str_find<value_type, size_type, traits_type, npos>
3111        (data(), size(), __s, __pos, traits_type::length(__s));
3112}
3113
3114template<class _CharT, class _Traits, class _Allocator>
3115typename basic_string<_CharT, _Traits, _Allocator>::size_type
3116basic_string<_CharT, _Traits, _Allocator>::find(value_type __c,
3117                                                size_type __pos) const _NOEXCEPT
3118{
3119    return __str_find<value_type, size_type, traits_type, npos>
3120        (data(), size(), __c, __pos);
3121}
3122
3123// rfind
3124
3125template<class _CharT, class _Traits, class _Allocator>
3126typename basic_string<_CharT, _Traits, _Allocator>::size_type
3127basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3128                                                 size_type __pos,
3129                                                 size_type __n) const _NOEXCEPT
3130{
3131    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::rfind(): received nullptr");
3132    return __str_rfind<value_type, size_type, traits_type, npos>
3133        (data(), size(), __s, __pos, __n);
3134}
3135
3136template<class _CharT, class _Traits, class _Allocator>
3137inline _LIBCPP_INLINE_VISIBILITY
3138typename basic_string<_CharT, _Traits, _Allocator>::size_type
3139basic_string<_CharT, _Traits, _Allocator>::rfind(const basic_string& __str,
3140                                                 size_type __pos) const _NOEXCEPT
3141{
3142    return __str_rfind<value_type, size_type, traits_type, npos>
3143        (data(), size(), __str.data(), __pos, __str.size());
3144}
3145
3146template<class _CharT, class _Traits, class _Allocator>
3147inline _LIBCPP_INLINE_VISIBILITY
3148typename basic_string<_CharT, _Traits, _Allocator>::size_type
3149basic_string<_CharT, _Traits, _Allocator>::rfind(__self_view __sv,
3150                                                size_type __pos) const _NOEXCEPT
3151{
3152    return __str_rfind<value_type, size_type, traits_type, npos>
3153        (data(), size(), __sv.data(), __pos, __sv.size());
3154}
3155
3156template<class _CharT, class _Traits, class _Allocator>
3157inline _LIBCPP_INLINE_VISIBILITY
3158typename basic_string<_CharT, _Traits, _Allocator>::size_type
3159basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3160                                                 size_type __pos) const _NOEXCEPT
3161{
3162    _LIBCPP_ASSERT(__s != nullptr, "string::rfind(): received nullptr");
3163    return __str_rfind<value_type, size_type, traits_type, npos>
3164        (data(), size(), __s, __pos, traits_type::length(__s));
3165}
3166
3167template<class _CharT, class _Traits, class _Allocator>
3168typename basic_string<_CharT, _Traits, _Allocator>::size_type
3169basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c,
3170                                                 size_type __pos) const _NOEXCEPT
3171{
3172    return __str_rfind<value_type, size_type, traits_type, npos>
3173        (data(), size(), __c, __pos);
3174}
3175
3176// find_first_of
3177
3178template<class _CharT, class _Traits, class _Allocator>
3179typename basic_string<_CharT, _Traits, _Allocator>::size_type
3180basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3181                                                         size_type __pos,
3182                                                         size_type __n) const _NOEXCEPT
3183{
3184    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_of(): received nullptr");
3185    return __str_find_first_of<value_type, size_type, traits_type, npos>
3186        (data(), size(), __s, __pos, __n);
3187}
3188
3189template<class _CharT, class _Traits, class _Allocator>
3190inline _LIBCPP_INLINE_VISIBILITY
3191typename basic_string<_CharT, _Traits, _Allocator>::size_type
3192basic_string<_CharT, _Traits, _Allocator>::find_first_of(const basic_string& __str,
3193                                                         size_type __pos) const _NOEXCEPT
3194{
3195    return __str_find_first_of<value_type, size_type, traits_type, npos>
3196        (data(), size(), __str.data(), __pos, __str.size());
3197}
3198
3199template<class _CharT, class _Traits, class _Allocator>
3200inline _LIBCPP_INLINE_VISIBILITY
3201typename basic_string<_CharT, _Traits, _Allocator>::size_type
3202basic_string<_CharT, _Traits, _Allocator>::find_first_of(__self_view __sv,
3203                                                size_type __pos) const _NOEXCEPT
3204{
3205    return __str_find_first_of<value_type, size_type, traits_type, npos>
3206        (data(), size(), __sv.data(), __pos, __sv.size());
3207}
3208
3209template<class _CharT, class _Traits, class _Allocator>
3210inline _LIBCPP_INLINE_VISIBILITY
3211typename basic_string<_CharT, _Traits, _Allocator>::size_type
3212basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3213                                                         size_type __pos) const _NOEXCEPT
3214{
3215    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_of(): received nullptr");
3216    return __str_find_first_of<value_type, size_type, traits_type, npos>
3217        (data(), size(), __s, __pos, traits_type::length(__s));
3218}
3219
3220template<class _CharT, class _Traits, class _Allocator>
3221inline _LIBCPP_INLINE_VISIBILITY
3222typename basic_string<_CharT, _Traits, _Allocator>::size_type
3223basic_string<_CharT, _Traits, _Allocator>::find_first_of(value_type __c,
3224                                                         size_type __pos) const _NOEXCEPT
3225{
3226    return find(__c, __pos);
3227}
3228
3229// find_last_of
3230
3231template<class _CharT, class _Traits, class _Allocator>
3232typename basic_string<_CharT, _Traits, _Allocator>::size_type
3233basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3234                                                        size_type __pos,
3235                                                        size_type __n) const _NOEXCEPT
3236{
3237    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_of(): received nullptr");
3238    return __str_find_last_of<value_type, size_type, traits_type, npos>
3239        (data(), size(), __s, __pos, __n);
3240}
3241
3242template<class _CharT, class _Traits, class _Allocator>
3243inline _LIBCPP_INLINE_VISIBILITY
3244typename basic_string<_CharT, _Traits, _Allocator>::size_type
3245basic_string<_CharT, _Traits, _Allocator>::find_last_of(const basic_string& __str,
3246                                                        size_type __pos) const _NOEXCEPT
3247{
3248    return __str_find_last_of<value_type, size_type, traits_type, npos>
3249        (data(), size(), __str.data(), __pos, __str.size());
3250}
3251
3252template<class _CharT, class _Traits, class _Allocator>
3253inline _LIBCPP_INLINE_VISIBILITY
3254typename basic_string<_CharT, _Traits, _Allocator>::size_type
3255basic_string<_CharT, _Traits, _Allocator>::find_last_of(__self_view __sv,
3256                                                size_type __pos) const _NOEXCEPT
3257{
3258    return __str_find_last_of<value_type, size_type, traits_type, npos>
3259        (data(), size(), __sv.data(), __pos, __sv.size());
3260}
3261
3262template<class _CharT, class _Traits, class _Allocator>
3263inline _LIBCPP_INLINE_VISIBILITY
3264typename basic_string<_CharT, _Traits, _Allocator>::size_type
3265basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3266                                                        size_type __pos) const _NOEXCEPT
3267{
3268    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_of(): received nullptr");
3269    return __str_find_last_of<value_type, size_type, traits_type, npos>
3270        (data(), size(), __s, __pos, traits_type::length(__s));
3271}
3272
3273template<class _CharT, class _Traits, class _Allocator>
3274inline _LIBCPP_INLINE_VISIBILITY
3275typename basic_string<_CharT, _Traits, _Allocator>::size_type
3276basic_string<_CharT, _Traits, _Allocator>::find_last_of(value_type __c,
3277                                                        size_type __pos) const _NOEXCEPT
3278{
3279    return rfind(__c, __pos);
3280}
3281
3282// find_first_not_of
3283
3284template<class _CharT, class _Traits, class _Allocator>
3285typename basic_string<_CharT, _Traits, _Allocator>::size_type
3286basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3287                                                             size_type __pos,
3288                                                             size_type __n) const _NOEXCEPT
3289{
3290    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_not_of(): received nullptr");
3291    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3292        (data(), size(), __s, __pos, __n);
3293}
3294
3295template<class _CharT, class _Traits, class _Allocator>
3296inline _LIBCPP_INLINE_VISIBILITY
3297typename basic_string<_CharT, _Traits, _Allocator>::size_type
3298basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const basic_string& __str,
3299                                                             size_type __pos) const _NOEXCEPT
3300{
3301    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3302        (data(), size(), __str.data(), __pos, __str.size());
3303}
3304
3305template<class _CharT, class _Traits, class _Allocator>
3306inline _LIBCPP_INLINE_VISIBILITY
3307typename basic_string<_CharT, _Traits, _Allocator>::size_type
3308basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(__self_view __sv,
3309                                                size_type __pos) const _NOEXCEPT
3310{
3311    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3312        (data(), size(), __sv.data(), __pos, __sv.size());
3313}
3314
3315template<class _CharT, class _Traits, class _Allocator>
3316inline _LIBCPP_INLINE_VISIBILITY
3317typename basic_string<_CharT, _Traits, _Allocator>::size_type
3318basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3319                                                             size_type __pos) const _NOEXCEPT
3320{
3321    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_not_of(): received nullptr");
3322    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3323        (data(), size(), __s, __pos, traits_type::length(__s));
3324}
3325
3326template<class _CharT, class _Traits, class _Allocator>
3327inline _LIBCPP_INLINE_VISIBILITY
3328typename basic_string<_CharT, _Traits, _Allocator>::size_type
3329basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c,
3330                                                             size_type __pos) const _NOEXCEPT
3331{
3332    return __str_find_first_not_of<value_type, size_type, traits_type, npos>
3333        (data(), size(), __c, __pos);
3334}
3335
3336// find_last_not_of
3337
3338template<class _CharT, class _Traits, class _Allocator>
3339typename basic_string<_CharT, _Traits, _Allocator>::size_type
3340basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3341                                                            size_type __pos,
3342                                                            size_type __n) const _NOEXCEPT
3343{
3344    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_not_of(): received nullptr");
3345    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3346        (data(), size(), __s, __pos, __n);
3347}
3348
3349template<class _CharT, class _Traits, class _Allocator>
3350inline _LIBCPP_INLINE_VISIBILITY
3351typename basic_string<_CharT, _Traits, _Allocator>::size_type
3352basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const basic_string& __str,
3353                                                            size_type __pos) const _NOEXCEPT
3354{
3355    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3356        (data(), size(), __str.data(), __pos, __str.size());
3357}
3358
3359template<class _CharT, class _Traits, class _Allocator>
3360inline _LIBCPP_INLINE_VISIBILITY
3361typename basic_string<_CharT, _Traits, _Allocator>::size_type
3362basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(__self_view __sv,
3363                                                size_type __pos) const _NOEXCEPT
3364{
3365    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3366        (data(), size(), __sv.data(), __pos, __sv.size());
3367}
3368
3369template<class _CharT, class _Traits, class _Allocator>
3370inline _LIBCPP_INLINE_VISIBILITY
3371typename basic_string<_CharT, _Traits, _Allocator>::size_type
3372basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3373                                                            size_type __pos) const _NOEXCEPT
3374{
3375    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_not_of(): received nullptr");
3376    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3377        (data(), size(), __s, __pos, traits_type::length(__s));
3378}
3379
3380template<class _CharT, class _Traits, class _Allocator>
3381inline _LIBCPP_INLINE_VISIBILITY
3382typename basic_string<_CharT, _Traits, _Allocator>::size_type
3383basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(value_type __c,
3384                                                            size_type __pos) const _NOEXCEPT
3385{
3386    return __str_find_last_not_of<value_type, size_type, traits_type, npos>
3387        (data(), size(), __c, __pos);
3388}
3389
3390// compare
3391
3392template <class _CharT, class _Traits, class _Allocator>
3393inline _LIBCPP_INLINE_VISIBILITY
3394int
3395basic_string<_CharT, _Traits, _Allocator>::compare(__self_view __sv) const _NOEXCEPT
3396{
3397    size_t __lhs_sz = size();
3398    size_t __rhs_sz = __sv.size();
3399    int __result = traits_type::compare(data(), __sv.data(),
3400                                        _VSTD::min(__lhs_sz, __rhs_sz));
3401    if (__result != 0)
3402        return __result;
3403    if (__lhs_sz < __rhs_sz)
3404        return -1;
3405    if (__lhs_sz > __rhs_sz)
3406        return 1;
3407    return 0;
3408}
3409
3410template <class _CharT, class _Traits, class _Allocator>
3411inline _LIBCPP_INLINE_VISIBILITY
3412int
3413basic_string<_CharT, _Traits, _Allocator>::compare(const basic_string& __str) const _NOEXCEPT
3414{
3415    return compare(__self_view(__str));
3416}
3417
3418template <class _CharT, class _Traits, class _Allocator>
3419int
3420basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3421                                                   size_type __n1,
3422                                                   const value_type* __s,
3423                                                   size_type __n2) const
3424{
3425    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::compare(): received nullptr");
3426    size_type __sz = size();
3427    if (__pos1 > __sz || __n2 == npos)
3428        this->__throw_out_of_range();
3429    size_type __rlen = _VSTD::min(__n1, __sz - __pos1);
3430    int __r = traits_type::compare(data() + __pos1, __s, _VSTD::min(__rlen, __n2));
3431    if (__r == 0)
3432    {
3433        if (__rlen < __n2)
3434            __r = -1;
3435        else if (__rlen > __n2)
3436            __r = 1;
3437    }
3438    return __r;
3439}
3440
3441template <class _CharT, class _Traits, class _Allocator>
3442inline _LIBCPP_INLINE_VISIBILITY
3443int
3444basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3445                                                   size_type __n1,
3446                                                   __self_view __sv) const
3447{
3448    return compare(__pos1, __n1, __sv.data(), __sv.size());
3449}
3450
3451template <class _CharT, class _Traits, class _Allocator>
3452inline _LIBCPP_INLINE_VISIBILITY
3453int
3454basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3455                                                   size_type __n1,
3456                                                   const basic_string& __str) const
3457{
3458    return compare(__pos1, __n1, __str.data(), __str.size());
3459}
3460
3461template <class _CharT, class _Traits, class _Allocator>
3462template <class _Tp>
3463typename enable_if
3464<
3465	__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value,
3466	int
3467>::type
3468basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3469                                                   size_type __n1,
3470                                                   const _Tp& __t,
3471                                                   size_type __pos2,
3472                                                   size_type __n2) const
3473{
3474    __self_view __sv = __t;
3475    return __self_view(*this).substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
3476}
3477
3478template <class _CharT, class _Traits, class _Allocator>
3479int
3480basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3481                                                   size_type __n1,
3482                                                   const basic_string& __str,
3483                                                   size_type __pos2,
3484                                                   size_type __n2) const
3485{
3486        return compare(__pos1, __n1, __self_view(__str), __pos2, __n2);
3487}
3488
3489template <class _CharT, class _Traits, class _Allocator>
3490int
3491basic_string<_CharT, _Traits, _Allocator>::compare(const value_type* __s) const _NOEXCEPT
3492{
3493    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3494    return compare(0, npos, __s, traits_type::length(__s));
3495}
3496
3497template <class _CharT, class _Traits, class _Allocator>
3498int
3499basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3500                                                   size_type __n1,
3501                                                   const value_type* __s) const
3502{
3503    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3504    return compare(__pos1, __n1, __s, traits_type::length(__s));
3505}
3506
3507// __invariants
3508
3509template<class _CharT, class _Traits, class _Allocator>
3510inline _LIBCPP_INLINE_VISIBILITY
3511bool
3512basic_string<_CharT, _Traits, _Allocator>::__invariants() const
3513{
3514    if (size() > capacity())
3515        return false;
3516    if (capacity() < __min_cap - 1)
3517        return false;
3518    if (data() == 0)
3519        return false;
3520    if (data()[size()] != value_type(0))
3521        return false;
3522    return true;
3523}
3524
3525// operator==
3526
3527template<class _CharT, class _Traits, class _Allocator>
3528inline _LIBCPP_INLINE_VISIBILITY
3529bool
3530operator==(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3531           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3532{
3533    size_t __lhs_sz = __lhs.size();
3534    return __lhs_sz == __rhs.size() && _Traits::compare(__lhs.data(),
3535                                                        __rhs.data(),
3536                                                        __lhs_sz) == 0;
3537}
3538
3539template<class _Allocator>
3540inline _LIBCPP_INLINE_VISIBILITY
3541bool
3542operator==(const basic_string<char, char_traits<char>, _Allocator>& __lhs,
3543           const basic_string<char, char_traits<char>, _Allocator>& __rhs) _NOEXCEPT
3544{
3545    size_t __lhs_sz = __lhs.size();
3546    if (__lhs_sz != __rhs.size())
3547        return false;
3548    const char* __lp = __lhs.data();
3549    const char* __rp = __rhs.data();
3550    if (__lhs.__is_long())
3551        return char_traits<char>::compare(__lp, __rp, __lhs_sz) == 0;
3552    for (; __lhs_sz != 0; --__lhs_sz, ++__lp, ++__rp)
3553        if (*__lp != *__rp)
3554            return false;
3555    return true;
3556}
3557
3558template<class _CharT, class _Traits, class _Allocator>
3559inline _LIBCPP_INLINE_VISIBILITY
3560bool
3561operator==(const _CharT* __lhs,
3562           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3563{
3564    typedef basic_string<_CharT, _Traits, _Allocator> _String;
3565    _LIBCPP_ASSERT(__lhs != nullptr, "operator==(char*, basic_string): received nullptr");
3566    size_t __lhs_len = _Traits::length(__lhs);
3567    if (__lhs_len != __rhs.size()) return false;
3568    return __rhs.compare(0, _String::npos, __lhs, __lhs_len) == 0;
3569}
3570
3571template<class _CharT, class _Traits, class _Allocator>
3572inline _LIBCPP_INLINE_VISIBILITY
3573bool
3574operator==(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3575           const _CharT* __rhs) _NOEXCEPT
3576{
3577    typedef basic_string<_CharT, _Traits, _Allocator> _String;
3578    _LIBCPP_ASSERT(__rhs != nullptr, "operator==(basic_string, char*): received nullptr");
3579    size_t __rhs_len = _Traits::length(__rhs);
3580    if (__rhs_len != __lhs.size()) return false;
3581    return __lhs.compare(0, _String::npos, __rhs, __rhs_len) == 0;
3582}
3583
3584template<class _CharT, class _Traits, class _Allocator>
3585inline _LIBCPP_INLINE_VISIBILITY
3586bool
3587operator!=(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3588           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3589{
3590    return !(__lhs == __rhs);
3591}
3592
3593template<class _CharT, class _Traits, class _Allocator>
3594inline _LIBCPP_INLINE_VISIBILITY
3595bool
3596operator!=(const _CharT* __lhs,
3597           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3598{
3599    return !(__lhs == __rhs);
3600}
3601
3602template<class _CharT, class _Traits, class _Allocator>
3603inline _LIBCPP_INLINE_VISIBILITY
3604bool
3605operator!=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3606           const _CharT* __rhs) _NOEXCEPT
3607{
3608    return !(__lhs == __rhs);
3609}
3610
3611// operator<
3612
3613template<class _CharT, class _Traits, class _Allocator>
3614inline _LIBCPP_INLINE_VISIBILITY
3615bool
3616operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3617           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3618{
3619    return __lhs.compare(__rhs) < 0;
3620}
3621
3622template<class _CharT, class _Traits, class _Allocator>
3623inline _LIBCPP_INLINE_VISIBILITY
3624bool
3625operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3626           const _CharT* __rhs) _NOEXCEPT
3627{
3628    return __lhs.compare(__rhs) < 0;
3629}
3630
3631template<class _CharT, class _Traits, class _Allocator>
3632inline _LIBCPP_INLINE_VISIBILITY
3633bool
3634operator< (const _CharT* __lhs,
3635           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3636{
3637    return __rhs.compare(__lhs) > 0;
3638}
3639
3640// operator>
3641
3642template<class _CharT, class _Traits, class _Allocator>
3643inline _LIBCPP_INLINE_VISIBILITY
3644bool
3645operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3646           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3647{
3648    return __rhs < __lhs;
3649}
3650
3651template<class _CharT, class _Traits, class _Allocator>
3652inline _LIBCPP_INLINE_VISIBILITY
3653bool
3654operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3655           const _CharT* __rhs) _NOEXCEPT
3656{
3657    return __rhs < __lhs;
3658}
3659
3660template<class _CharT, class _Traits, class _Allocator>
3661inline _LIBCPP_INLINE_VISIBILITY
3662bool
3663operator> (const _CharT* __lhs,
3664           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3665{
3666    return __rhs < __lhs;
3667}
3668
3669// operator<=
3670
3671template<class _CharT, class _Traits, class _Allocator>
3672inline _LIBCPP_INLINE_VISIBILITY
3673bool
3674operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3675           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3676{
3677    return !(__rhs < __lhs);
3678}
3679
3680template<class _CharT, class _Traits, class _Allocator>
3681inline _LIBCPP_INLINE_VISIBILITY
3682bool
3683operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3684           const _CharT* __rhs) _NOEXCEPT
3685{
3686    return !(__rhs < __lhs);
3687}
3688
3689template<class _CharT, class _Traits, class _Allocator>
3690inline _LIBCPP_INLINE_VISIBILITY
3691bool
3692operator<=(const _CharT* __lhs,
3693           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3694{
3695    return !(__rhs < __lhs);
3696}
3697
3698// operator>=
3699
3700template<class _CharT, class _Traits, class _Allocator>
3701inline _LIBCPP_INLINE_VISIBILITY
3702bool
3703operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3704           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3705{
3706    return !(__lhs < __rhs);
3707}
3708
3709template<class _CharT, class _Traits, class _Allocator>
3710inline _LIBCPP_INLINE_VISIBILITY
3711bool
3712operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3713           const _CharT* __rhs) _NOEXCEPT
3714{
3715    return !(__lhs < __rhs);
3716}
3717
3718template<class _CharT, class _Traits, class _Allocator>
3719inline _LIBCPP_INLINE_VISIBILITY
3720bool
3721operator>=(const _CharT* __lhs,
3722           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3723{
3724    return !(__lhs < __rhs);
3725}
3726
3727// operator +
3728
3729template<class _CharT, class _Traits, class _Allocator>
3730basic_string<_CharT, _Traits, _Allocator>
3731operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3732          const basic_string<_CharT, _Traits, _Allocator>& __rhs)
3733{
3734    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3735    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3736    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3737    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3738    __r.append(__rhs.data(), __rhs_sz);
3739    return __r;
3740}
3741
3742template<class _CharT, class _Traits, class _Allocator>
3743basic_string<_CharT, _Traits, _Allocator>
3744operator+(const _CharT* __lhs , const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3745{
3746    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3747    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = _Traits::length(__lhs);
3748    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3749    __r.__init(__lhs, __lhs_sz, __lhs_sz + __rhs_sz);
3750    __r.append(__rhs.data(), __rhs_sz);
3751    return __r;
3752}
3753
3754template<class _CharT, class _Traits, class _Allocator>
3755basic_string<_CharT, _Traits, _Allocator>
3756operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3757{
3758    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3759    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3760    __r.__init(&__lhs, 1, 1 + __rhs_sz);
3761    __r.append(__rhs.data(), __rhs_sz);
3762    return __r;
3763}
3764
3765template<class _CharT, class _Traits, class _Allocator>
3766basic_string<_CharT, _Traits, _Allocator>
3767operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs)
3768{
3769    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3770    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3771    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = _Traits::length(__rhs);
3772    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3773    __r.append(__rhs, __rhs_sz);
3774    return __r;
3775}
3776
3777template<class _CharT, class _Traits, class _Allocator>
3778basic_string<_CharT, _Traits, _Allocator>
3779operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, _CharT __rhs)
3780{
3781    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3782    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3783    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + 1);
3784    __r.push_back(__rhs);
3785    return __r;
3786}
3787
3788#ifndef _LIBCPP_CXX03_LANG
3789
3790template<class _CharT, class _Traits, class _Allocator>
3791inline _LIBCPP_INLINE_VISIBILITY
3792basic_string<_CharT, _Traits, _Allocator>
3793operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs)
3794{
3795    return _VSTD::move(__lhs.append(__rhs));
3796}
3797
3798template<class _CharT, class _Traits, class _Allocator>
3799inline _LIBCPP_INLINE_VISIBILITY
3800basic_string<_CharT, _Traits, _Allocator>
3801operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
3802{
3803    return _VSTD::move(__rhs.insert(0, __lhs));
3804}
3805
3806template<class _CharT, class _Traits, class _Allocator>
3807inline _LIBCPP_INLINE_VISIBILITY
3808basic_string<_CharT, _Traits, _Allocator>
3809operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
3810{
3811    return _VSTD::move(__lhs.append(__rhs));
3812}
3813
3814template<class _CharT, class _Traits, class _Allocator>
3815inline _LIBCPP_INLINE_VISIBILITY
3816basic_string<_CharT, _Traits, _Allocator>
3817operator+(const _CharT* __lhs , basic_string<_CharT,_Traits,_Allocator>&& __rhs)
3818{
3819    return _VSTD::move(__rhs.insert(0, __lhs));
3820}
3821
3822template<class _CharT, class _Traits, class _Allocator>
3823inline _LIBCPP_INLINE_VISIBILITY
3824basic_string<_CharT, _Traits, _Allocator>
3825operator+(_CharT __lhs, basic_string<_CharT,_Traits,_Allocator>&& __rhs)
3826{
3827    __rhs.insert(__rhs.begin(), __lhs);
3828    return _VSTD::move(__rhs);
3829}
3830
3831template<class _CharT, class _Traits, class _Allocator>
3832inline _LIBCPP_INLINE_VISIBILITY
3833basic_string<_CharT, _Traits, _Allocator>
3834operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const _CharT* __rhs)
3835{
3836    return _VSTD::move(__lhs.append(__rhs));
3837}
3838
3839template<class _CharT, class _Traits, class _Allocator>
3840inline _LIBCPP_INLINE_VISIBILITY
3841basic_string<_CharT, _Traits, _Allocator>
3842operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, _CharT __rhs)
3843{
3844    __lhs.push_back(__rhs);
3845    return _VSTD::move(__lhs);
3846}
3847
3848#endif  // _LIBCPP_CXX03_LANG
3849
3850// swap
3851
3852template<class _CharT, class _Traits, class _Allocator>
3853inline _LIBCPP_INLINE_VISIBILITY
3854void
3855swap(basic_string<_CharT, _Traits, _Allocator>& __lhs,
3856     basic_string<_CharT, _Traits, _Allocator>& __rhs)
3857     _NOEXCEPT_(_NOEXCEPT_(__lhs.swap(__rhs)))
3858{
3859    __lhs.swap(__rhs);
3860}
3861
3862#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
3863
3864typedef basic_string<char16_t> u16string;
3865typedef basic_string<char32_t> u32string;
3866
3867#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
3868
3869_LIBCPP_FUNC_VIS int                stoi  (const string& __str, size_t* __idx = 0, int __base = 10);
3870_LIBCPP_FUNC_VIS long               stol  (const string& __str, size_t* __idx = 0, int __base = 10);
3871_LIBCPP_FUNC_VIS unsigned long      stoul (const string& __str, size_t* __idx = 0, int __base = 10);
3872_LIBCPP_FUNC_VIS long long          stoll (const string& __str, size_t* __idx = 0, int __base = 10);
3873_LIBCPP_FUNC_VIS unsigned long long stoull(const string& __str, size_t* __idx = 0, int __base = 10);
3874
3875_LIBCPP_FUNC_VIS float       stof (const string& __str, size_t* __idx = 0);
3876_LIBCPP_FUNC_VIS double      stod (const string& __str, size_t* __idx = 0);
3877_LIBCPP_FUNC_VIS long double stold(const string& __str, size_t* __idx = 0);
3878
3879_LIBCPP_FUNC_VIS string to_string(int __val);
3880_LIBCPP_FUNC_VIS string to_string(unsigned __val);
3881_LIBCPP_FUNC_VIS string to_string(long __val);
3882_LIBCPP_FUNC_VIS string to_string(unsigned long __val);
3883_LIBCPP_FUNC_VIS string to_string(long long __val);
3884_LIBCPP_FUNC_VIS string to_string(unsigned long long __val);
3885_LIBCPP_FUNC_VIS string to_string(float __val);
3886_LIBCPP_FUNC_VIS string to_string(double __val);
3887_LIBCPP_FUNC_VIS string to_string(long double __val);
3888
3889_LIBCPP_FUNC_VIS int                stoi  (const wstring& __str, size_t* __idx = 0, int __base = 10);
3890_LIBCPP_FUNC_VIS long               stol  (const wstring& __str, size_t* __idx = 0, int __base = 10);
3891_LIBCPP_FUNC_VIS unsigned long      stoul (const wstring& __str, size_t* __idx = 0, int __base = 10);
3892_LIBCPP_FUNC_VIS long long          stoll (const wstring& __str, size_t* __idx = 0, int __base = 10);
3893_LIBCPP_FUNC_VIS unsigned long long stoull(const wstring& __str, size_t* __idx = 0, int __base = 10);
3894
3895_LIBCPP_FUNC_VIS float       stof (const wstring& __str, size_t* __idx = 0);
3896_LIBCPP_FUNC_VIS double      stod (const wstring& __str, size_t* __idx = 0);
3897_LIBCPP_FUNC_VIS long double stold(const wstring& __str, size_t* __idx = 0);
3898
3899_LIBCPP_FUNC_VIS wstring to_wstring(int __val);
3900_LIBCPP_FUNC_VIS wstring to_wstring(unsigned __val);
3901_LIBCPP_FUNC_VIS wstring to_wstring(long __val);
3902_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long __val);
3903_LIBCPP_FUNC_VIS wstring to_wstring(long long __val);
3904_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long long __val);
3905_LIBCPP_FUNC_VIS wstring to_wstring(float __val);
3906_LIBCPP_FUNC_VIS wstring to_wstring(double __val);
3907_LIBCPP_FUNC_VIS wstring to_wstring(long double __val);
3908
3909template<class _CharT, class _Traits, class _Allocator>
3910    const typename basic_string<_CharT, _Traits, _Allocator>::size_type
3911                   basic_string<_CharT, _Traits, _Allocator>::npos;
3912
3913template<class _CharT, class _Traits, class _Allocator>
3914struct _LIBCPP_TEMPLATE_VIS hash<basic_string<_CharT, _Traits, _Allocator> >
3915    : public unary_function<basic_string<_CharT, _Traits, _Allocator>, size_t>
3916{
3917    size_t
3918        operator()(const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT;
3919};
3920
3921template<class _CharT, class _Traits, class _Allocator>
3922size_t
3923hash<basic_string<_CharT, _Traits, _Allocator> >::operator()(
3924        const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT
3925{
3926    return __do_string_hash(__val.data(), __val.data() + __val.size());
3927}
3928
3929template<class _CharT, class _Traits, class _Allocator>
3930basic_ostream<_CharT, _Traits>&
3931operator<<(basic_ostream<_CharT, _Traits>& __os,
3932           const basic_string<_CharT, _Traits, _Allocator>& __str);
3933
3934template<class _CharT, class _Traits, class _Allocator>
3935basic_istream<_CharT, _Traits>&
3936operator>>(basic_istream<_CharT, _Traits>& __is,
3937           basic_string<_CharT, _Traits, _Allocator>& __str);
3938
3939template<class _CharT, class _Traits, class _Allocator>
3940basic_istream<_CharT, _Traits>&
3941getline(basic_istream<_CharT, _Traits>& __is,
3942        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
3943
3944template<class _CharT, class _Traits, class _Allocator>
3945inline _LIBCPP_INLINE_VISIBILITY
3946basic_istream<_CharT, _Traits>&
3947getline(basic_istream<_CharT, _Traits>& __is,
3948        basic_string<_CharT, _Traits, _Allocator>& __str);
3949
3950#ifndef _LIBCPP_CXX03_LANG
3951
3952template<class _CharT, class _Traits, class _Allocator>
3953inline _LIBCPP_INLINE_VISIBILITY
3954basic_istream<_CharT, _Traits>&
3955getline(basic_istream<_CharT, _Traits>&& __is,
3956        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
3957
3958template<class _CharT, class _Traits, class _Allocator>
3959inline _LIBCPP_INLINE_VISIBILITY
3960basic_istream<_CharT, _Traits>&
3961getline(basic_istream<_CharT, _Traits>&& __is,
3962        basic_string<_CharT, _Traits, _Allocator>& __str);
3963
3964#endif  // _LIBCPP_CXX03_LANG
3965
3966#if _LIBCPP_DEBUG_LEVEL >= 2
3967
3968template<class _CharT, class _Traits, class _Allocator>
3969bool
3970basic_string<_CharT, _Traits, _Allocator>::__dereferenceable(const const_iterator* __i) const
3971{
3972    return this->data() <= _VSTD::__to_raw_pointer(__i->base()) &&
3973           _VSTD::__to_raw_pointer(__i->base()) < this->data() + this->size();
3974}
3975
3976template<class _CharT, class _Traits, class _Allocator>
3977bool
3978basic_string<_CharT, _Traits, _Allocator>::__decrementable(const const_iterator* __i) const
3979{
3980    return this->data() < _VSTD::__to_raw_pointer(__i->base()) &&
3981           _VSTD::__to_raw_pointer(__i->base()) <= this->data() + this->size();
3982}
3983
3984template<class _CharT, class _Traits, class _Allocator>
3985bool
3986basic_string<_CharT, _Traits, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
3987{
3988    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
3989    return this->data() <= __p && __p <= this->data() + this->size();
3990}
3991
3992template<class _CharT, class _Traits, class _Allocator>
3993bool
3994basic_string<_CharT, _Traits, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
3995{
3996    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
3997    return this->data() <= __p && __p < this->data() + this->size();
3998}
3999
4000#endif  // _LIBCPP_DEBUG_LEVEL >= 2
4001
4002_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_string<char>)
4003_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_string<wchar_t>)
4004
4005#if _LIBCPP_STD_VER > 11 
4006// Literal suffixes for basic_string [basic.string.literals]
4007inline namespace literals
4008{
4009  inline namespace string_literals
4010  {
4011    inline _LIBCPP_INLINE_VISIBILITY
4012    basic_string<char> operator "" s( const char *__str, size_t __len )
4013    {
4014        return basic_string<char> (__str, __len);
4015    }
4016
4017    inline _LIBCPP_INLINE_VISIBILITY
4018    basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
4019    {
4020        return basic_string<wchar_t> (__str, __len);
4021    }
4022
4023    inline _LIBCPP_INLINE_VISIBILITY
4024    basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
4025    {
4026        return basic_string<char16_t> (__str, __len);
4027    }
4028
4029    inline _LIBCPP_INLINE_VISIBILITY
4030    basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
4031    {
4032        return basic_string<char32_t> (__str, __len);
4033    }
4034  }
4035}
4036#endif
4037
4038_LIBCPP_END_NAMESPACE_STD
4039
4040_LIBCPP_POP_MACROS
4041
4042#endif  // _LIBCPP_STRING
4043