xref: /freebsd-12.1/contrib/libc++/include/string (revision ea2ef993)
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, size_type n = npos,
102                 const allocator_type& a = allocator_type());
103    basic_string(const value_type* s, const allocator_type& a = allocator_type());
104    basic_string(const value_type* s, size_type n, const allocator_type& a = allocator_type());
105    basic_string(size_type n, value_type c, const allocator_type& a = allocator_type());
106    template<class InputIterator>
107        basic_string(InputIterator begin, InputIterator end,
108                     const allocator_type& a = allocator_type());
109    basic_string(initializer_list<value_type>, const Allocator& = Allocator());
110    basic_string(const basic_string&, const Allocator&);
111    basic_string(basic_string&&, const Allocator&);
112
113    ~basic_string();
114
115    basic_string& operator=(const basic_string& str);
116    basic_string& operator=(basic_string&& str)
117        noexcept(
118             allocator_type::propagate_on_container_move_assignment::value &&
119             is_nothrow_move_assignable<allocator_type>::value);
120    basic_string& operator=(const value_type* s);
121    basic_string& operator=(value_type c);
122    basic_string& operator=(initializer_list<value_type>);
123
124    iterator       begin() noexcept;
125    const_iterator begin() const noexcept;
126    iterator       end() noexcept;
127    const_iterator end() const noexcept;
128
129    reverse_iterator       rbegin() noexcept;
130    const_reverse_iterator rbegin() const noexcept;
131    reverse_iterator       rend() noexcept;
132    const_reverse_iterator rend() const noexcept;
133
134    const_iterator         cbegin() const noexcept;
135    const_iterator         cend() const noexcept;
136    const_reverse_iterator crbegin() const noexcept;
137    const_reverse_iterator crend() const noexcept;
138
139    size_type size() const noexcept;
140    size_type length() const noexcept;
141    size_type max_size() const noexcept;
142    size_type capacity() const noexcept;
143
144    void resize(size_type n, value_type c);
145    void resize(size_type n);
146
147    void reserve(size_type res_arg = 0);
148    void shrink_to_fit();
149    void clear() noexcept;
150    bool empty() const noexcept;
151
152    const_reference operator[](size_type pos) const;
153    reference       operator[](size_type pos);
154
155    const_reference at(size_type n) const;
156    reference       at(size_type n);
157
158    basic_string& operator+=(const basic_string& str);
159    basic_string& operator+=(const value_type* s);
160    basic_string& operator+=(value_type c);
161    basic_string& operator+=(initializer_list<value_type>);
162
163    basic_string& append(const basic_string& str);
164    basic_string& append(const basic_string& str, size_type pos, size_type n=npos); //C++14
165    basic_string& append(const value_type* s, size_type n);
166    basic_string& append(const value_type* s);
167    basic_string& append(size_type n, value_type c);
168    template<class InputIterator>
169        basic_string& append(InputIterator first, InputIterator last);
170    basic_string& append(initializer_list<value_type>);
171
172    void push_back(value_type c);
173    void pop_back();
174    reference       front();
175    const_reference front() const;
176    reference       back();
177    const_reference back() const;
178
179    basic_string& assign(const basic_string& str);
180    basic_string& assign(basic_string&& str);
181    basic_string& assign(const basic_string& str, size_type pos, size_type n=npos); // C++14
182    basic_string& assign(const value_type* s, size_type n);
183    basic_string& assign(const value_type* s);
184    basic_string& assign(size_type n, value_type c);
185    template<class InputIterator>
186        basic_string& assign(InputIterator first, InputIterator last);
187    basic_string& assign(initializer_list<value_type>);
188
189    basic_string& insert(size_type pos1, const basic_string& str);
190    basic_string& insert(size_type pos1, const basic_string& str,
191                         size_type pos2, size_type n);
192    basic_string& insert(size_type pos, const value_type* s, size_type n=npos); //C++14
193    basic_string& insert(size_type pos, const value_type* s);
194    basic_string& insert(size_type pos, size_type n, value_type c);
195    iterator      insert(const_iterator p, value_type c);
196    iterator      insert(const_iterator p, size_type n, value_type c);
197    template<class InputIterator>
198        iterator insert(const_iterator p, InputIterator first, InputIterator last);
199    iterator      insert(const_iterator p, initializer_list<value_type>);
200
201    basic_string& erase(size_type pos = 0, size_type n = npos);
202    iterator      erase(const_iterator position);
203    iterator      erase(const_iterator first, const_iterator last);
204
205    basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
206    basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
207                          size_type pos2, size_type n2=npos); // C++14
208    basic_string& replace(size_type pos, size_type n1, const value_type* s, size_type n2);
209    basic_string& replace(size_type pos, size_type n1, const value_type* s);
210    basic_string& replace(size_type pos, size_type n1, size_type n2, value_type c);
211    basic_string& replace(const_iterator i1, const_iterator i2, const basic_string& str);
212    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s, size_type n);
213    basic_string& replace(const_iterator i1, const_iterator i2, const value_type* s);
214    basic_string& replace(const_iterator i1, const_iterator i2, size_type n, value_type c);
215    template<class InputIterator>
216        basic_string& replace(const_iterator i1, const_iterator i2, InputIterator j1, InputIterator j2);
217    basic_string& replace(const_iterator i1, const_iterator i2, initializer_list<value_type>);
218
219    size_type copy(value_type* s, size_type n, size_type pos = 0) const;
220    basic_string substr(size_type pos = 0, size_type n = npos) const;
221
222    void swap(basic_string& str)
223        noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
224                 allocator_traits<allocator_type>::is_always_equal::value);  // C++17
225
226    const value_type* c_str() const noexcept;
227    const value_type* data() const noexcept;
228
229    allocator_type get_allocator() const noexcept;
230
231    size_type find(const basic_string& str, size_type pos = 0) const noexcept;
232    size_type find(const value_type* s, size_type pos, size_type n) const noexcept;
233    size_type find(const value_type* s, size_type pos = 0) const noexcept;
234    size_type find(value_type c, size_type pos = 0) const noexcept;
235
236    size_type rfind(const basic_string& str, size_type pos = npos) const noexcept;
237    size_type rfind(const value_type* s, size_type pos, size_type n) const noexcept;
238    size_type rfind(const value_type* s, size_type pos = npos) const noexcept;
239    size_type rfind(value_type c, size_type pos = npos) const noexcept;
240
241    size_type find_first_of(const basic_string& str, size_type pos = 0) const noexcept;
242    size_type find_first_of(const value_type* s, size_type pos, size_type n) const noexcept;
243    size_type find_first_of(const value_type* s, size_type pos = 0) const noexcept;
244    size_type find_first_of(value_type c, size_type pos = 0) const noexcept;
245
246    size_type find_last_of(const basic_string& str, size_type pos = npos) const noexcept;
247    size_type find_last_of(const value_type* s, size_type pos, size_type n) const noexcept;
248    size_type find_last_of(const value_type* s, size_type pos = npos) const noexcept;
249    size_type find_last_of(value_type c, size_type pos = npos) const noexcept;
250
251    size_type find_first_not_of(const basic_string& str, size_type pos = 0) const noexcept;
252    size_type find_first_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
253    size_type find_first_not_of(const value_type* s, size_type pos = 0) const noexcept;
254    size_type find_first_not_of(value_type c, size_type pos = 0) const noexcept;
255
256    size_type find_last_not_of(const basic_string& str, size_type pos = npos) const noexcept;
257    size_type find_last_not_of(const value_type* s, size_type pos, size_type n) const noexcept;
258    size_type find_last_not_of(const value_type* s, size_type pos = npos) const noexcept;
259    size_type find_last_not_of(value_type c, size_type pos = npos) const noexcept;
260
261    int compare(const basic_string& str) const noexcept;
262    int compare(size_type pos1, size_type n1, const basic_string& str) const;
263    int compare(size_type pos1, size_type n1, const basic_string& str,
264                size_type pos2, size_type n2=npos) const; // C++14
265    int compare(const value_type* s) const noexcept;
266    int compare(size_type pos1, size_type n1, const value_type* s) const;
267    int compare(size_type pos1, size_type n1, const value_type* s, size_type n2) const;
268
269    bool __invariants() const;
270};
271
272template<class charT, class traits, class Allocator>
273basic_string<charT, traits, Allocator>
274operator+(const basic_string<charT, traits, Allocator>& lhs,
275          const basic_string<charT, traits, Allocator>& rhs);
276
277template<class charT, class traits, class Allocator>
278basic_string<charT, traits, Allocator>
279operator+(const charT* lhs , const basic_string<charT,traits,Allocator>&rhs);
280
281template<class charT, class traits, class Allocator>
282basic_string<charT, traits, Allocator>
283operator+(charT lhs, const basic_string<charT,traits,Allocator>& rhs);
284
285template<class charT, class traits, class Allocator>
286basic_string<charT, traits, Allocator>
287operator+(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs);
288
289template<class charT, class traits, class Allocator>
290basic_string<charT, traits, Allocator>
291operator+(const basic_string<charT, traits, Allocator>& lhs, charT rhs);
292
293template<class charT, class traits, class Allocator>
294bool operator==(const basic_string<charT, traits, Allocator>& lhs,
295                const basic_string<charT, traits, Allocator>& rhs) noexcept;
296
297template<class charT, class traits, class Allocator>
298bool operator==(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
299
300template<class charT, class traits, class Allocator>
301bool operator==(const basic_string<charT,traits,Allocator>& lhs, const charT* rhs) noexcept;
302
303template<class charT, class traits, class Allocator>
304bool operator!=(const basic_string<charT,traits,Allocator>& lhs,
305                const basic_string<charT, traits, Allocator>& rhs) noexcept;
306
307template<class charT, class traits, class Allocator>
308bool operator!=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
309
310template<class charT, class traits, class Allocator>
311bool operator!=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
312
313template<class charT, class traits, class Allocator>
314bool operator< (const basic_string<charT, traits, Allocator>& lhs,
315                const basic_string<charT, traits, Allocator>& rhs) noexcept;
316
317template<class charT, class traits, class Allocator>
318bool operator< (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
319
320template<class charT, class traits, class Allocator>
321bool operator< (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
322
323template<class charT, class traits, class Allocator>
324bool operator> (const basic_string<charT, traits, Allocator>& lhs,
325                const basic_string<charT, traits, Allocator>& rhs) noexcept;
326
327template<class charT, class traits, class Allocator>
328bool operator> (const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
329
330template<class charT, class traits, class Allocator>
331bool operator> (const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
332
333template<class charT, class traits, class Allocator>
334bool operator<=(const basic_string<charT, traits, Allocator>& lhs,
335                const basic_string<charT, traits, Allocator>& rhs) noexcept;
336
337template<class charT, class traits, class Allocator>
338bool operator<=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
339
340template<class charT, class traits, class Allocator>
341bool operator<=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
342
343template<class charT, class traits, class Allocator>
344bool operator>=(const basic_string<charT, traits, Allocator>& lhs,
345                const basic_string<charT, traits, Allocator>& rhs) noexcept;
346
347template<class charT, class traits, class Allocator>
348bool operator>=(const basic_string<charT, traits, Allocator>& lhs, const charT* rhs) noexcept;
349
350template<class charT, class traits, class Allocator>
351bool operator>=(const charT* lhs, const basic_string<charT, traits, Allocator>& rhs) noexcept;
352
353template<class charT, class traits, class Allocator>
354void swap(basic_string<charT, traits, Allocator>& lhs,
355          basic_string<charT, traits, Allocator>& rhs)
356            noexcept(noexcept(lhs.swap(rhs)));
357
358template<class charT, class traits, class Allocator>
359basic_istream<charT, traits>&
360operator>>(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
361
362template<class charT, class traits, class Allocator>
363basic_ostream<charT, traits>&
364operator<<(basic_ostream<charT, traits>& os, const basic_string<charT, traits, Allocator>& str);
365
366template<class charT, class traits, class Allocator>
367basic_istream<charT, traits>&
368getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str,
369        charT delim);
370
371template<class charT, class traits, class Allocator>
372basic_istream<charT, traits>&
373getline(basic_istream<charT, traits>& is, basic_string<charT, traits, Allocator>& str);
374
375typedef basic_string<char>    string;
376typedef basic_string<wchar_t> wstring;
377typedef basic_string<char16_t> u16string;
378typedef basic_string<char32_t> u32string;
379
380int                stoi  (const string& str, size_t* idx = 0, int base = 10);
381long               stol  (const string& str, size_t* idx = 0, int base = 10);
382unsigned long      stoul (const string& str, size_t* idx = 0, int base = 10);
383long long          stoll (const string& str, size_t* idx = 0, int base = 10);
384unsigned long long stoull(const string& str, size_t* idx = 0, int base = 10);
385
386float       stof (const string& str, size_t* idx = 0);
387double      stod (const string& str, size_t* idx = 0);
388long double stold(const string& str, size_t* idx = 0);
389
390string to_string(int val);
391string to_string(unsigned val);
392string to_string(long val);
393string to_string(unsigned long val);
394string to_string(long long val);
395string to_string(unsigned long long val);
396string to_string(float val);
397string to_string(double val);
398string to_string(long double val);
399
400int                stoi  (const wstring& str, size_t* idx = 0, int base = 10);
401long               stol  (const wstring& str, size_t* idx = 0, int base = 10);
402unsigned long      stoul (const wstring& str, size_t* idx = 0, int base = 10);
403long long          stoll (const wstring& str, size_t* idx = 0, int base = 10);
404unsigned long long stoull(const wstring& str, size_t* idx = 0, int base = 10);
405
406float       stof (const wstring& str, size_t* idx = 0);
407double      stod (const wstring& str, size_t* idx = 0);
408long double stold(const wstring& str, size_t* idx = 0);
409
410wstring to_wstring(int val);
411wstring to_wstring(unsigned val);
412wstring to_wstring(long val);
413wstring to_wstring(unsigned long val);
414wstring to_wstring(long long val);
415wstring to_wstring(unsigned long long val);
416wstring to_wstring(float val);
417wstring to_wstring(double val);
418wstring to_wstring(long double val);
419
420template <> struct hash<string>;
421template <> struct hash<u16string>;
422template <> struct hash<u32string>;
423template <> struct hash<wstring>;
424
425basic_string<char>     operator "" s( const char *str,     size_t len ); // C++14
426basic_string<wchar_t>  operator "" s( const wchar_t *str,  size_t len ); // C++14
427basic_string<char16_t> operator "" s( const char16_t *str, size_t len ); // C++14
428basic_string<char32_t> operator "" s( const char32_t *str, size_t len ); // C++14
429
430}  // std
431
432*/
433
434#include <__config>
435#include <iosfwd>
436#include <cstring>
437#include <cstdio>  // For EOF.
438#include <cwchar>
439#include <algorithm>
440#include <iterator>
441#include <utility>
442#include <memory>
443#include <stdexcept>
444#include <type_traits>
445#include <initializer_list>
446#include <__functional_base>
447#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
448#include <cstdint>
449#endif
450#if defined(_LIBCPP_NO_EXCEPTIONS)
451#include <cassert>
452#endif
453
454#include <__undef_min_max>
455
456#include <__debug>
457
458#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
459#pragma GCC system_header
460#endif
461
462_LIBCPP_BEGIN_NAMESPACE_STD
463
464// fpos
465
466template <class _StateT>
467class _LIBCPP_TYPE_VIS_ONLY fpos
468{
469private:
470    _StateT __st_;
471    streamoff __off_;
472public:
473    _LIBCPP_INLINE_VISIBILITY fpos(streamoff __off = streamoff()) : __st_(), __off_(__off) {}
474
475    _LIBCPP_INLINE_VISIBILITY operator streamoff() const {return __off_;}
476
477    _LIBCPP_INLINE_VISIBILITY _StateT state() const {return __st_;}
478    _LIBCPP_INLINE_VISIBILITY void state(_StateT __st) {__st_ = __st;}
479
480    _LIBCPP_INLINE_VISIBILITY fpos& operator+=(streamoff __off) {__off_ += __off; return *this;}
481    _LIBCPP_INLINE_VISIBILITY fpos  operator+ (streamoff __off) const {fpos __t(*this); __t += __off; return __t;}
482    _LIBCPP_INLINE_VISIBILITY fpos& operator-=(streamoff __off) {__off_ -= __off; return *this;}
483    _LIBCPP_INLINE_VISIBILITY fpos  operator- (streamoff __off) const {fpos __t(*this); __t -= __off; return __t;}
484};
485
486template <class _StateT>
487inline _LIBCPP_INLINE_VISIBILITY
488streamoff operator-(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
489    {return streamoff(__x) - streamoff(__y);}
490
491template <class _StateT>
492inline _LIBCPP_INLINE_VISIBILITY
493bool operator==(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
494    {return streamoff(__x) == streamoff(__y);}
495
496template <class _StateT>
497inline _LIBCPP_INLINE_VISIBILITY
498bool operator!=(const fpos<_StateT>& __x, const fpos<_StateT>& __y)
499    {return streamoff(__x) != streamoff(__y);}
500
501// char_traits
502
503template <class _CharT>
504struct _LIBCPP_TYPE_VIS_ONLY char_traits
505{
506    typedef _CharT    char_type;
507    typedef int       int_type;
508    typedef streamoff off_type;
509    typedef streampos pos_type;
510    typedef mbstate_t state_type;
511
512    static inline void assign(char_type& __c1, const char_type& __c2) _NOEXCEPT
513        {__c1 = __c2;}
514    static inline _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT
515        {return __c1 == __c2;}
516    static inline _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT
517        {return __c1 < __c2;}
518
519    static int              compare(const char_type* __s1, const char_type* __s2, size_t __n);
520    static size_t           length(const char_type* __s);
521    static const char_type* find(const char_type* __s, size_t __n, const char_type& __a);
522    static char_type*       move(char_type* __s1, const char_type* __s2, size_t __n);
523    static char_type*       copy(char_type* __s1, const char_type* __s2, size_t __n);
524    static char_type*       assign(char_type* __s, size_t __n, char_type __a);
525
526    static inline _LIBCPP_CONSTEXPR int_type  not_eof(int_type __c) _NOEXCEPT
527        {return eq_int_type(__c, eof()) ? ~eof() : __c;}
528    static inline _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT
529        {return char_type(__c);}
530    static inline _LIBCPP_CONSTEXPR int_type  to_int_type(char_type __c) _NOEXCEPT
531        {return int_type(__c);}
532    static inline _LIBCPP_CONSTEXPR bool      eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT
533        {return __c1 == __c2;}
534    static inline _LIBCPP_CONSTEXPR int_type  eof() _NOEXCEPT
535        {return int_type(EOF);}
536};
537
538template <class _CharT>
539int
540char_traits<_CharT>::compare(const char_type* __s1, const char_type* __s2, size_t __n)
541{
542    for (; __n; --__n, ++__s1, ++__s2)
543    {
544        if (lt(*__s1, *__s2))
545            return -1;
546        if (lt(*__s2, *__s1))
547            return 1;
548    }
549    return 0;
550}
551
552template <class _CharT>
553inline _LIBCPP_INLINE_VISIBILITY
554size_t
555char_traits<_CharT>::length(const char_type* __s)
556{
557    size_t __len = 0;
558    for (; !eq(*__s, char_type(0)); ++__s)
559        ++__len;
560    return __len;
561}
562
563template <class _CharT>
564inline _LIBCPP_INLINE_VISIBILITY
565const _CharT*
566char_traits<_CharT>::find(const char_type* __s, size_t __n, const char_type& __a)
567{
568    for (; __n; --__n)
569    {
570        if (eq(*__s, __a))
571            return __s;
572        ++__s;
573    }
574    return 0;
575}
576
577template <class _CharT>
578_CharT*
579char_traits<_CharT>::move(char_type* __s1, const char_type* __s2, size_t __n)
580{
581    char_type* __r = __s1;
582    if (__s1 < __s2)
583    {
584        for (; __n; --__n, ++__s1, ++__s2)
585            assign(*__s1, *__s2);
586    }
587    else if (__s2 < __s1)
588    {
589        __s1 += __n;
590        __s2 += __n;
591        for (; __n; --__n)
592            assign(*--__s1, *--__s2);
593    }
594    return __r;
595}
596
597template <class _CharT>
598inline _LIBCPP_INLINE_VISIBILITY
599_CharT*
600char_traits<_CharT>::copy(char_type* __s1, const char_type* __s2, size_t __n)
601{
602    _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
603    char_type* __r = __s1;
604    for (; __n; --__n, ++__s1, ++__s2)
605        assign(*__s1, *__s2);
606    return __r;
607}
608
609template <class _CharT>
610inline _LIBCPP_INLINE_VISIBILITY
611_CharT*
612char_traits<_CharT>::assign(char_type* __s, size_t __n, char_type __a)
613{
614    char_type* __r = __s;
615    for (; __n; --__n, ++__s)
616        assign(*__s, __a);
617    return __r;
618}
619
620// char_traits<char>
621
622template <>
623struct _LIBCPP_TYPE_VIS_ONLY char_traits<char>
624{
625    typedef char      char_type;
626    typedef int       int_type;
627    typedef streamoff off_type;
628    typedef streampos pos_type;
629    typedef mbstate_t state_type;
630
631    static inline void assign(char_type& __c1, const char_type& __c2) _NOEXCEPT
632        {__c1 = __c2;}
633    static inline _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT
634            {return __c1 == __c2;}
635    static inline _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT
636        {return (unsigned char)__c1 < (unsigned char)__c2;}
637
638    static inline int compare(const char_type* __s1, const char_type* __s2, size_t __n)
639        {return __n == 0 ? 0 : memcmp(__s1, __s2, __n);}
640    static inline size_t length(const char_type* __s) {return strlen(__s);}
641    static inline const char_type* find(const char_type* __s, size_t __n, const char_type& __a)
642        {return __n == 0 ? NULL : (const char_type*) memchr(__s, to_int_type(__a), __n);}
643    static inline char_type* move(char_type* __s1, const char_type* __s2, size_t __n)
644        {return __n == 0 ? __s1 : (char_type*) memmove(__s1, __s2, __n);}
645    static inline char_type* copy(char_type* __s1, const char_type* __s2, size_t __n)
646        {
647            _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
648            return __n == 0 ? __s1 : (char_type*)memcpy(__s1, __s2, __n);
649        }
650    static inline char_type* assign(char_type* __s, size_t __n, char_type __a)
651        {return __n == 0 ? __s : (char_type*)memset(__s, to_int_type(__a), __n);}
652
653    static inline _LIBCPP_CONSTEXPR int_type  not_eof(int_type __c) _NOEXCEPT
654        {return eq_int_type(__c, eof()) ? ~eof() : __c;}
655    static inline _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT
656        {return char_type(__c);}
657    static inline _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT
658        {return int_type((unsigned char)__c);}
659    static inline _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT
660        {return __c1 == __c2;}
661    static inline _LIBCPP_CONSTEXPR int_type  eof() _NOEXCEPT
662        {return int_type(EOF);}
663};
664
665// char_traits<wchar_t>
666
667template <>
668struct _LIBCPP_TYPE_VIS_ONLY char_traits<wchar_t>
669{
670    typedef wchar_t   char_type;
671    typedef wint_t    int_type;
672    typedef streamoff off_type;
673    typedef streampos pos_type;
674    typedef mbstate_t state_type;
675
676    static inline void assign(char_type& __c1, const char_type& __c2) _NOEXCEPT
677        {__c1 = __c2;}
678    static inline _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT
679        {return __c1 == __c2;}
680    static inline _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT
681        {return __c1 < __c2;}
682
683    static inline int compare(const char_type* __s1, const char_type* __s2, size_t __n)
684        {return __n == 0 ? 0 : wmemcmp(__s1, __s2, __n);}
685    static inline size_t length(const char_type* __s)
686        {return wcslen(__s);}
687    static inline const char_type* find(const char_type* __s, size_t __n, const char_type& __a)
688        {return __n == 0 ? NULL : (const char_type*)wmemchr(__s, __a, __n);}
689    static inline char_type* move(char_type* __s1, const char_type* __s2, size_t __n)
690        {return __n == 0 ? __s1 : (char_type*)wmemmove(__s1, __s2, __n);}
691    static inline char_type* copy(char_type* __s1, const char_type* __s2, size_t __n)
692        {
693            _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
694            return __n == 0 ? __s1 : (char_type*)wmemcpy(__s1, __s2, __n);
695        }
696    static inline char_type* assign(char_type* __s, size_t __n, char_type __a)
697        {return __n == 0 ? __s : (char_type*)wmemset(__s, __a, __n);}
698
699    static inline _LIBCPP_CONSTEXPR int_type  not_eof(int_type __c) _NOEXCEPT
700        {return eq_int_type(__c, eof()) ? ~eof() : __c;}
701    static inline _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT
702        {return char_type(__c);}
703    static inline _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT
704        {return int_type(__c);}
705    static inline _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT
706        {return __c1 == __c2;}
707    static inline _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT
708        {return int_type(WEOF);}
709};
710
711#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
712
713template <>
714struct _LIBCPP_TYPE_VIS_ONLY char_traits<char16_t>
715{
716    typedef char16_t       char_type;
717    typedef uint_least16_t int_type;
718    typedef streamoff      off_type;
719    typedef u16streampos   pos_type;
720    typedef mbstate_t      state_type;
721
722    static inline void assign(char_type& __c1, const char_type& __c2) _NOEXCEPT
723        {__c1 = __c2;}
724    static inline _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT
725        {return __c1 == __c2;}
726    static inline _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT
727        {return __c1 < __c2;}
728
729    static int              compare(const char_type* __s1, const char_type* __s2, size_t __n);
730    static size_t           length(const char_type* __s);
731    static const char_type* find(const char_type* __s, size_t __n, const char_type& __a);
732    static char_type*       move(char_type* __s1, const char_type* __s2, size_t __n);
733    static char_type*       copy(char_type* __s1, const char_type* __s2, size_t __n);
734    static char_type*       assign(char_type* __s, size_t __n, char_type __a);
735
736    static inline _LIBCPP_CONSTEXPR int_type  not_eof(int_type __c) _NOEXCEPT
737        {return eq_int_type(__c, eof()) ? ~eof() : __c;}
738    static inline _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT
739        {return char_type(__c);}
740    static inline _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT
741        {return int_type(__c);}
742    static inline _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT
743        {return __c1 == __c2;}
744    static inline _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT
745        {return int_type(0xDFFF);}
746};
747
748inline _LIBCPP_INLINE_VISIBILITY
749int
750char_traits<char16_t>::compare(const char_type* __s1, const char_type* __s2, size_t __n)
751{
752    for (; __n; --__n, ++__s1, ++__s2)
753    {
754        if (lt(*__s1, *__s2))
755            return -1;
756        if (lt(*__s2, *__s1))
757            return 1;
758    }
759    return 0;
760}
761
762inline _LIBCPP_INLINE_VISIBILITY
763size_t
764char_traits<char16_t>::length(const char_type* __s)
765{
766    size_t __len = 0;
767    for (; !eq(*__s, char_type(0)); ++__s)
768        ++__len;
769    return __len;
770}
771
772inline _LIBCPP_INLINE_VISIBILITY
773const char16_t*
774char_traits<char16_t>::find(const char_type* __s, size_t __n, const char_type& __a)
775{
776    for (; __n; --__n)
777    {
778        if (eq(*__s, __a))
779            return __s;
780        ++__s;
781    }
782    return 0;
783}
784
785inline _LIBCPP_INLINE_VISIBILITY
786char16_t*
787char_traits<char16_t>::move(char_type* __s1, const char_type* __s2, size_t __n)
788{
789    char_type* __r = __s1;
790    if (__s1 < __s2)
791    {
792        for (; __n; --__n, ++__s1, ++__s2)
793            assign(*__s1, *__s2);
794    }
795    else if (__s2 < __s1)
796    {
797        __s1 += __n;
798        __s2 += __n;
799        for (; __n; --__n)
800            assign(*--__s1, *--__s2);
801    }
802    return __r;
803}
804
805inline _LIBCPP_INLINE_VISIBILITY
806char16_t*
807char_traits<char16_t>::copy(char_type* __s1, const char_type* __s2, size_t __n)
808{
809    _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
810    char_type* __r = __s1;
811    for (; __n; --__n, ++__s1, ++__s2)
812        assign(*__s1, *__s2);
813    return __r;
814}
815
816inline _LIBCPP_INLINE_VISIBILITY
817char16_t*
818char_traits<char16_t>::assign(char_type* __s, size_t __n, char_type __a)
819{
820    char_type* __r = __s;
821    for (; __n; --__n, ++__s)
822        assign(*__s, __a);
823    return __r;
824}
825
826template <>
827struct _LIBCPP_TYPE_VIS_ONLY char_traits<char32_t>
828{
829    typedef char32_t       char_type;
830    typedef uint_least32_t int_type;
831    typedef streamoff      off_type;
832    typedef u32streampos   pos_type;
833    typedef mbstate_t      state_type;
834
835    static inline void assign(char_type& __c1, const char_type& __c2) _NOEXCEPT
836        {__c1 = __c2;}
837    static inline _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT
838        {return __c1 == __c2;}
839    static inline _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT
840        {return __c1 < __c2;}
841
842    static int              compare(const char_type* __s1, const char_type* __s2, size_t __n);
843    static size_t           length(const char_type* __s);
844    static const char_type* find(const char_type* __s, size_t __n, const char_type& __a);
845    static char_type*       move(char_type* __s1, const char_type* __s2, size_t __n);
846    static char_type*       copy(char_type* __s1, const char_type* __s2, size_t __n);
847    static char_type*       assign(char_type* __s, size_t __n, char_type __a);
848
849    static inline _LIBCPP_CONSTEXPR int_type  not_eof(int_type __c) _NOEXCEPT
850        {return eq_int_type(__c, eof()) ? ~eof() : __c;}
851    static inline _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT
852        {return char_type(__c);}
853    static inline _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT
854        {return int_type(__c);}
855    static inline _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT
856        {return __c1 == __c2;}
857    static inline _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT
858        {return int_type(0xFFFFFFFF);}
859};
860
861inline _LIBCPP_INLINE_VISIBILITY
862int
863char_traits<char32_t>::compare(const char_type* __s1, const char_type* __s2, size_t __n)
864{
865    for (; __n; --__n, ++__s1, ++__s2)
866    {
867        if (lt(*__s1, *__s2))
868            return -1;
869        if (lt(*__s2, *__s1))
870            return 1;
871    }
872    return 0;
873}
874
875inline _LIBCPP_INLINE_VISIBILITY
876size_t
877char_traits<char32_t>::length(const char_type* __s)
878{
879    size_t __len = 0;
880    for (; !eq(*__s, char_type(0)); ++__s)
881        ++__len;
882    return __len;
883}
884
885inline _LIBCPP_INLINE_VISIBILITY
886const char32_t*
887char_traits<char32_t>::find(const char_type* __s, size_t __n, const char_type& __a)
888{
889    for (; __n; --__n)
890    {
891        if (eq(*__s, __a))
892            return __s;
893        ++__s;
894    }
895    return 0;
896}
897
898inline _LIBCPP_INLINE_VISIBILITY
899char32_t*
900char_traits<char32_t>::move(char_type* __s1, const char_type* __s2, size_t __n)
901{
902    char_type* __r = __s1;
903    if (__s1 < __s2)
904    {
905        for (; __n; --__n, ++__s1, ++__s2)
906            assign(*__s1, *__s2);
907    }
908    else if (__s2 < __s1)
909    {
910        __s1 += __n;
911        __s2 += __n;
912        for (; __n; --__n)
913            assign(*--__s1, *--__s2);
914    }
915    return __r;
916}
917
918inline _LIBCPP_INLINE_VISIBILITY
919char32_t*
920char_traits<char32_t>::copy(char_type* __s1, const char_type* __s2, size_t __n)
921{
922    _LIBCPP_ASSERT(__s2 < __s1 || __s2 >= __s1+__n, "char_traits::copy overlapped range");
923    char_type* __r = __s1;
924    for (; __n; --__n, ++__s1, ++__s2)
925        assign(*__s1, *__s2);
926    return __r;
927}
928
929inline _LIBCPP_INLINE_VISIBILITY
930char32_t*
931char_traits<char32_t>::assign(char_type* __s, size_t __n, char_type __a)
932{
933    char_type* __r = __s;
934    for (; __n; --__n, ++__s)
935        assign(*__s, __a);
936    return __r;
937}
938
939#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
940
941// helper fns for basic_string
942
943// __str_find
944template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
945_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
946__str_find(const _CharT *__p, _SizeT __sz,
947             _CharT __c, _SizeT __pos) _NOEXCEPT
948{
949    if (__pos >= __sz)
950        return __npos;
951    const _CharT* __r = _Traits::find(__p + __pos, __sz - __pos, __c);
952    if (__r == 0)
953        return __npos;
954    return static_cast<_SizeT>(__r - __p);
955}
956
957template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
958_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
959__str_find(const _CharT *__p, _SizeT __sz,
960       const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
961{
962    if (__pos > __sz || __sz - __pos < __n)
963        return __npos;
964    if (__n == 0)
965        return __pos;
966    const _CharT* __r =
967        _VSTD::__search(__p + __pos, __p + __sz,
968                        __s, __s + __n, _Traits::eq,
969                        random_access_iterator_tag(), random_access_iterator_tag());
970    if (__r == __p + __sz)
971        return __npos;
972    return static_cast<_SizeT>(__r - __p);
973}
974
975
976// __str_rfind
977
978template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
979_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
980__str_rfind(const _CharT *__p, _SizeT __sz,
981              _CharT __c, _SizeT __pos) _NOEXCEPT
982{
983    if (__sz < 1)
984        return __npos;
985    if (__pos < __sz)
986        ++__pos;
987    else
988        __pos = __sz;
989    for (const _CharT* __ps = __p + __pos; __ps != __p;)
990    {
991        if (_Traits::eq(*--__ps, __c))
992            return static_cast<_SizeT>(__ps - __p);
993    }
994    return __npos;
995}
996
997template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
998_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
999__str_rfind(const _CharT *__p, _SizeT __sz,
1000        const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
1001{
1002    __pos = _VSTD::min(__pos, __sz);
1003    if (__n < __sz - __pos)
1004        __pos += __n;
1005    else
1006        __pos = __sz;
1007    const _CharT* __r = _VSTD::__find_end(
1008                  __p, __p + __pos, __s, __s + __n, _Traits::eq,
1009                        random_access_iterator_tag(), random_access_iterator_tag());
1010    if (__n > 0 && __r == __p + __pos)
1011        return __npos;
1012    return static_cast<_SizeT>(__r - __p);
1013}
1014
1015// __str_find_first_of
1016template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1017_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1018__str_find_first_of(const _CharT *__p, _SizeT __sz,
1019                const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
1020{
1021    if (__pos >= __sz || __n == 0)
1022        return __npos;
1023    const _CharT* __r = _VSTD::__find_first_of_ce
1024        (__p + __pos, __p + __sz, __s, __s + __n, _Traits::eq );
1025    if (__r == __p + __sz)
1026        return __npos;
1027    return static_cast<_SizeT>(__r - __p);
1028}
1029
1030
1031// __str_find_last_of
1032template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1033_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1034__str_find_last_of(const _CharT *__p, _SizeT __sz,
1035               const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
1036    {
1037    if (__n != 0)
1038    {
1039        if (__pos < __sz)
1040            ++__pos;
1041        else
1042            __pos = __sz;
1043        for (const _CharT* __ps = __p + __pos; __ps != __p;)
1044        {
1045            const _CharT* __r = _Traits::find(__s, __n, *--__ps);
1046            if (__r)
1047                return static_cast<_SizeT>(__ps - __p);
1048        }
1049    }
1050    return __npos;
1051}
1052
1053
1054// __str_find_first_not_of
1055template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1056_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1057__str_find_first_not_of(const _CharT *__p, _SizeT __sz,
1058                    const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
1059{
1060    if (__pos < __sz)
1061    {
1062        const _CharT* __pe = __p + __sz;
1063        for (const _CharT* __ps = __p + __pos; __ps != __pe; ++__ps)
1064            if (_Traits::find(__s, __n, *__ps) == 0)
1065                return static_cast<_SizeT>(__ps - __p);
1066    }
1067    return __npos;
1068}
1069
1070
1071template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1072_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1073__str_find_first_not_of(const _CharT *__p, _SizeT __sz,
1074                          _CharT __c, _SizeT __pos) _NOEXCEPT
1075{
1076    if (__pos < __sz)
1077    {
1078        const _CharT* __pe = __p + __sz;
1079        for (const _CharT* __ps = __p + __pos; __ps != __pe; ++__ps)
1080            if (!_Traits::eq(*__ps, __c))
1081                return static_cast<_SizeT>(__ps - __p);
1082    }
1083    return __npos;
1084}
1085
1086
1087// __str_find_last_not_of
1088template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1089_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1090__str_find_last_not_of(const _CharT *__p, _SizeT __sz,
1091                   const _CharT* __s, _SizeT __pos, _SizeT __n) _NOEXCEPT
1092{
1093    if (__pos < __sz)
1094        ++__pos;
1095    else
1096        __pos = __sz;
1097    for (const _CharT* __ps = __p + __pos; __ps != __p;)
1098        if (_Traits::find(__s, __n, *--__ps) == 0)
1099            return static_cast<_SizeT>(__ps - __p);
1100    return __npos;
1101}
1102
1103
1104template<class _CharT, class _SizeT, class _Traits, _SizeT __npos>
1105_SizeT _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1106__str_find_last_not_of(const _CharT *__p, _SizeT __sz,
1107                         _CharT __c, _SizeT __pos) _NOEXCEPT
1108{
1109    if (__pos < __sz)
1110        ++__pos;
1111    else
1112        __pos = __sz;
1113    for (const _CharT* __ps = __p + __pos; __ps != __p;)
1114        if (!_Traits::eq(*--__ps, __c))
1115            return static_cast<_SizeT>(__ps - __p);
1116    return __npos;
1117}
1118
1119template<class _Ptr>
1120size_t _LIBCPP_INLINE_VISIBILITY __do_string_hash(_Ptr __p, _Ptr __e)
1121{
1122    typedef typename iterator_traits<_Ptr>::value_type value_type;
1123    return __murmur2_or_cityhash<size_t>()(__p, (__e-__p)*sizeof(value_type));
1124}
1125
1126// basic_string
1127
1128template<class _CharT, class _Traits, class _Allocator>
1129basic_string<_CharT, _Traits, _Allocator>
1130operator+(const basic_string<_CharT, _Traits, _Allocator>& __x,
1131          const basic_string<_CharT, _Traits, _Allocator>& __y);
1132
1133template<class _CharT, class _Traits, class _Allocator>
1134basic_string<_CharT, _Traits, _Allocator>
1135operator+(const _CharT* __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
1136
1137template<class _CharT, class _Traits, class _Allocator>
1138basic_string<_CharT, _Traits, _Allocator>
1139operator+(_CharT __x, const basic_string<_CharT,_Traits,_Allocator>& __y);
1140
1141template<class _CharT, class _Traits, class _Allocator>
1142basic_string<_CharT, _Traits, _Allocator>
1143operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, const _CharT* __y);
1144
1145template<class _CharT, class _Traits, class _Allocator>
1146basic_string<_CharT, _Traits, _Allocator>
1147operator+(const basic_string<_CharT, _Traits, _Allocator>& __x, _CharT __y);
1148
1149template <bool>
1150class _LIBCPP_TYPE_VIS_ONLY __basic_string_common
1151{
1152protected:
1153    void __throw_length_error() const;
1154    void __throw_out_of_range() const;
1155};
1156
1157template <bool __b>
1158void
1159__basic_string_common<__b>::__throw_length_error() const
1160{
1161#ifndef _LIBCPP_NO_EXCEPTIONS
1162    throw length_error("basic_string");
1163#else
1164    assert(!"basic_string length_error");
1165#endif
1166}
1167
1168template <bool __b>
1169void
1170__basic_string_common<__b>::__throw_out_of_range() const
1171{
1172#ifndef _LIBCPP_NO_EXCEPTIONS
1173    throw out_of_range("basic_string");
1174#else
1175    assert(!"basic_string out_of_range");
1176#endif
1177}
1178
1179#ifdef _LIBCPP_MSVC
1180#pragma warning( push )
1181#pragma warning( disable: 4231 )
1182#endif // _LIBCPP_MSVC
1183_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_TYPE_VIS __basic_string_common<true>)
1184#ifdef _LIBCPP_MSVC
1185#pragma warning( pop )
1186#endif // _LIBCPP_MSVC
1187
1188#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
1189
1190template <class _CharT, size_t = sizeof(_CharT)>
1191struct __padding
1192{
1193    unsigned char __xx[sizeof(_CharT)-1];
1194};
1195
1196template <class _CharT>
1197struct __padding<_CharT, 1>
1198{
1199};
1200
1201#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
1202
1203template<class _CharT, class _Traits, class _Allocator>
1204class _LIBCPP_TYPE_VIS_ONLY basic_string
1205    : private __basic_string_common<true>
1206{
1207public:
1208    typedef basic_string                                 __self;
1209    typedef _Traits                                      traits_type;
1210    typedef typename traits_type::char_type              value_type;
1211    typedef _Allocator                                   allocator_type;
1212    typedef allocator_traits<allocator_type>             __alloc_traits;
1213    typedef typename __alloc_traits::size_type           size_type;
1214    typedef typename __alloc_traits::difference_type     difference_type;
1215    typedef value_type&                                  reference;
1216    typedef const value_type&                            const_reference;
1217    typedef typename __alloc_traits::pointer             pointer;
1218    typedef typename __alloc_traits::const_pointer       const_pointer;
1219
1220    static_assert(is_pod<value_type>::value, "Character type of basic_string must be a POD");
1221    static_assert((is_same<_CharT, value_type>::value),
1222                  "traits_type::char_type must be the same type as CharT");
1223    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
1224                  "Allocator::value_type must be same type as value_type");
1225#if defined(_LIBCPP_RAW_ITERATORS)
1226    typedef pointer                                      iterator;
1227    typedef const_pointer                                const_iterator;
1228#else  // defined(_LIBCPP_RAW_ITERATORS)
1229    typedef __wrap_iter<pointer>                         iterator;
1230    typedef __wrap_iter<const_pointer>                   const_iterator;
1231#endif  // defined(_LIBCPP_RAW_ITERATORS)
1232    typedef _VSTD::reverse_iterator<iterator>             reverse_iterator;
1233    typedef _VSTD::reverse_iterator<const_iterator>       const_reverse_iterator;
1234
1235private:
1236
1237#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
1238
1239    struct __long
1240    {
1241        pointer   __data_;
1242        size_type __size_;
1243        size_type __cap_;
1244    };
1245
1246#if _LIBCPP_BIG_ENDIAN
1247    enum {__short_mask = 0x01};
1248    enum {__long_mask  = 0x1ul};
1249#else  // _LIBCPP_BIG_ENDIAN
1250    enum {__short_mask = 0x80};
1251    enum {__long_mask  = ~(size_type(~0) >> 1)};
1252#endif  // _LIBCPP_BIG_ENDIAN
1253
1254    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
1255                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
1256
1257    struct __short
1258    {
1259        value_type __data_[__min_cap];
1260        struct
1261            : __padding<value_type>
1262        {
1263            unsigned char __size_;
1264        };
1265    };
1266
1267#else
1268
1269    struct __long
1270    {
1271        size_type __cap_;
1272        size_type __size_;
1273        pointer   __data_;
1274    };
1275
1276#if _LIBCPP_BIG_ENDIAN
1277    enum {__short_mask = 0x80};
1278    enum {__long_mask  = ~(size_type(~0) >> 1)};
1279#else  // _LIBCPP_BIG_ENDIAN
1280    enum {__short_mask = 0x01};
1281    enum {__long_mask  = 0x1ul};
1282#endif  // _LIBCPP_BIG_ENDIAN
1283
1284    enum {__min_cap = (sizeof(__long) - 1)/sizeof(value_type) > 2 ?
1285                      (sizeof(__long) - 1)/sizeof(value_type) : 2};
1286
1287    struct __short
1288    {
1289        union
1290        {
1291            unsigned char __size_;
1292            value_type __lx;
1293        };
1294        value_type __data_[__min_cap];
1295    };
1296
1297#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
1298
1299    union __ulx{__long __lx; __short __lxx;};
1300
1301    enum {__n_words = sizeof(__ulx) / sizeof(size_type)};
1302
1303    struct __raw
1304    {
1305        size_type __words[__n_words];
1306    };
1307
1308    struct __rep
1309    {
1310        union
1311        {
1312            __long  __l;
1313            __short __s;
1314            __raw   __r;
1315        };
1316    };
1317
1318    __compressed_pair<__rep, allocator_type> __r_;
1319
1320public:
1321    static const size_type npos = -1;
1322
1323    _LIBCPP_INLINE_VISIBILITY basic_string()
1324        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
1325
1326    _LIBCPP_INLINE_VISIBILITY explicit basic_string(const allocator_type& __a)
1327#if _LIBCPP_STD_VER <= 14
1328        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value);
1329#else
1330        _NOEXCEPT;
1331#endif
1332
1333    basic_string(const basic_string& __str);
1334    basic_string(const basic_string& __str, const allocator_type& __a);
1335
1336#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1337    _LIBCPP_INLINE_VISIBILITY
1338    basic_string(basic_string&& __str)
1339#if _LIBCPP_STD_VER <= 14
1340        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
1341#else
1342        _NOEXCEPT;
1343#endif
1344
1345    _LIBCPP_INLINE_VISIBILITY
1346    basic_string(basic_string&& __str, const allocator_type& __a);
1347#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1348    _LIBCPP_INLINE_VISIBILITY basic_string(const value_type* __s);
1349    _LIBCPP_INLINE_VISIBILITY
1350    basic_string(const value_type* __s, const allocator_type& __a);
1351    _LIBCPP_INLINE_VISIBILITY
1352    basic_string(const value_type* __s, size_type __n);
1353    _LIBCPP_INLINE_VISIBILITY
1354    basic_string(const value_type* __s, size_type __n, const allocator_type& __a);
1355    _LIBCPP_INLINE_VISIBILITY
1356    basic_string(size_type __n, value_type __c);
1357    _LIBCPP_INLINE_VISIBILITY
1358    basic_string(size_type __n, value_type __c, const allocator_type& __a);
1359    basic_string(const basic_string& __str, size_type __pos, size_type __n = npos,
1360                 const allocator_type& __a = allocator_type());
1361    template<class _InputIterator>
1362        _LIBCPP_INLINE_VISIBILITY
1363        basic_string(_InputIterator __first, _InputIterator __last);
1364    template<class _InputIterator>
1365        _LIBCPP_INLINE_VISIBILITY
1366        basic_string(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
1367#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1368    _LIBCPP_INLINE_VISIBILITY
1369    basic_string(initializer_list<value_type> __il);
1370    _LIBCPP_INLINE_VISIBILITY
1371    basic_string(initializer_list<value_type> __il, const allocator_type& __a);
1372#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1373
1374    ~basic_string();
1375
1376    basic_string& operator=(const basic_string& __str);
1377#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1378    _LIBCPP_INLINE_VISIBILITY
1379    basic_string& operator=(basic_string&& __str)
1380        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
1381                   is_nothrow_move_assignable<allocator_type>::value);
1382#endif
1383    _LIBCPP_INLINE_VISIBILITY basic_string& operator=(const value_type* __s) {return assign(__s);}
1384    basic_string& operator=(value_type __c);
1385#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1386    _LIBCPP_INLINE_VISIBILITY
1387    basic_string& operator=(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
1388#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1389
1390#if _LIBCPP_DEBUG_LEVEL >= 2
1391    _LIBCPP_INLINE_VISIBILITY
1392    iterator begin() _NOEXCEPT
1393        {return iterator(this, __get_pointer());}
1394    _LIBCPP_INLINE_VISIBILITY
1395    const_iterator begin() const _NOEXCEPT
1396        {return const_iterator(this, __get_pointer());}
1397    _LIBCPP_INLINE_VISIBILITY
1398    iterator end() _NOEXCEPT
1399        {return iterator(this, __get_pointer() + size());}
1400    _LIBCPP_INLINE_VISIBILITY
1401    const_iterator end() const _NOEXCEPT
1402        {return const_iterator(this, __get_pointer() + size());}
1403#else
1404    _LIBCPP_INLINE_VISIBILITY
1405    iterator begin() _NOEXCEPT
1406        {return iterator(__get_pointer());}
1407    _LIBCPP_INLINE_VISIBILITY
1408    const_iterator begin() const _NOEXCEPT
1409        {return const_iterator(__get_pointer());}
1410    _LIBCPP_INLINE_VISIBILITY
1411    iterator end() _NOEXCEPT
1412        {return iterator(__get_pointer() + size());}
1413    _LIBCPP_INLINE_VISIBILITY
1414    const_iterator end() const _NOEXCEPT
1415        {return const_iterator(__get_pointer() + size());}
1416#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1417    _LIBCPP_INLINE_VISIBILITY
1418    reverse_iterator rbegin() _NOEXCEPT
1419        {return reverse_iterator(end());}
1420    _LIBCPP_INLINE_VISIBILITY
1421    const_reverse_iterator rbegin() const _NOEXCEPT
1422        {return const_reverse_iterator(end());}
1423    _LIBCPP_INLINE_VISIBILITY
1424    reverse_iterator rend() _NOEXCEPT
1425        {return reverse_iterator(begin());}
1426    _LIBCPP_INLINE_VISIBILITY
1427    const_reverse_iterator rend() const _NOEXCEPT
1428        {return const_reverse_iterator(begin());}
1429
1430    _LIBCPP_INLINE_VISIBILITY
1431    const_iterator cbegin() const _NOEXCEPT
1432        {return begin();}
1433    _LIBCPP_INLINE_VISIBILITY
1434    const_iterator cend() const _NOEXCEPT
1435        {return end();}
1436    _LIBCPP_INLINE_VISIBILITY
1437    const_reverse_iterator crbegin() const _NOEXCEPT
1438        {return rbegin();}
1439    _LIBCPP_INLINE_VISIBILITY
1440    const_reverse_iterator crend() const _NOEXCEPT
1441        {return rend();}
1442
1443    _LIBCPP_INLINE_VISIBILITY size_type size() const _NOEXCEPT
1444        {return __is_long() ? __get_long_size() : __get_short_size();}
1445    _LIBCPP_INLINE_VISIBILITY size_type length() const _NOEXCEPT {return size();}
1446    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT;
1447    _LIBCPP_INLINE_VISIBILITY size_type capacity() const _NOEXCEPT
1448        {return (__is_long() ? __get_long_cap()
1449                             : static_cast<size_type>(__min_cap)) - 1;}
1450
1451    void resize(size_type __n, value_type __c);
1452    _LIBCPP_INLINE_VISIBILITY void resize(size_type __n) {resize(__n, value_type());}
1453
1454    void reserve(size_type res_arg = 0);
1455    _LIBCPP_INLINE_VISIBILITY
1456    void shrink_to_fit() _NOEXCEPT {reserve();}
1457    _LIBCPP_INLINE_VISIBILITY
1458    void clear() _NOEXCEPT;
1459    _LIBCPP_INLINE_VISIBILITY bool empty() const _NOEXCEPT {return size() == 0;}
1460
1461    _LIBCPP_INLINE_VISIBILITY const_reference operator[](size_type __pos) const;
1462    _LIBCPP_INLINE_VISIBILITY reference       operator[](size_type __pos);
1463
1464    const_reference at(size_type __n) const;
1465    reference       at(size_type __n);
1466
1467    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const basic_string& __str) {return append(__str);}
1468    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(const value_type* __s)         {return append(__s);}
1469    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(value_type __c)            {push_back(__c); return *this;}
1470#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1471    _LIBCPP_INLINE_VISIBILITY basic_string& operator+=(initializer_list<value_type> __il) {return append(__il);}
1472#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1473
1474    _LIBCPP_INLINE_VISIBILITY
1475    basic_string& append(const basic_string& __str);
1476    basic_string& append(const basic_string& __str, size_type __pos, size_type __n=npos);
1477    basic_string& append(const value_type* __s, size_type __n);
1478    basic_string& append(const value_type* __s);
1479    basic_string& append(size_type __n, value_type __c);
1480    template<class _InputIterator>
1481        typename enable_if
1482        <
1483             __is_input_iterator  <_InputIterator>::value &&
1484            !__is_forward_iterator<_InputIterator>::value,
1485            basic_string&
1486        >::type
1487        append(_InputIterator __first, _InputIterator __last);
1488    template<class _ForwardIterator>
1489        typename enable_if
1490        <
1491            __is_forward_iterator<_ForwardIterator>::value,
1492            basic_string&
1493        >::type
1494        append(_ForwardIterator __first, _ForwardIterator __last);
1495#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1496    _LIBCPP_INLINE_VISIBILITY
1497    basic_string& append(initializer_list<value_type> __il) {return append(__il.begin(), __il.size());}
1498#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1499
1500    void push_back(value_type __c);
1501    _LIBCPP_INLINE_VISIBILITY
1502    void pop_back();
1503    _LIBCPP_INLINE_VISIBILITY reference       front();
1504    _LIBCPP_INLINE_VISIBILITY const_reference front() const;
1505    _LIBCPP_INLINE_VISIBILITY reference       back();
1506    _LIBCPP_INLINE_VISIBILITY const_reference back() const;
1507
1508    _LIBCPP_INLINE_VISIBILITY
1509    basic_string& assign(const basic_string& __str);
1510#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1511    _LIBCPP_INLINE_VISIBILITY
1512    basic_string& assign(basic_string&& str)
1513        {*this = _VSTD::move(str); return *this;}
1514#endif
1515    basic_string& assign(const basic_string& __str, size_type __pos, size_type __n=npos);
1516    basic_string& assign(const value_type* __s, size_type __n);
1517    basic_string& assign(const value_type* __s);
1518    basic_string& assign(size_type __n, value_type __c);
1519    template<class _InputIterator>
1520        typename enable_if
1521        <
1522             __is_input_iterator  <_InputIterator>::value &&
1523            !__is_forward_iterator<_InputIterator>::value,
1524            basic_string&
1525        >::type
1526        assign(_InputIterator __first, _InputIterator __last);
1527    template<class _ForwardIterator>
1528        typename enable_if
1529        <
1530            __is_forward_iterator<_ForwardIterator>::value,
1531            basic_string&
1532        >::type
1533        assign(_ForwardIterator __first, _ForwardIterator __last);
1534#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1535    _LIBCPP_INLINE_VISIBILITY
1536    basic_string& assign(initializer_list<value_type> __il) {return assign(__il.begin(), __il.size());}
1537#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1538
1539    _LIBCPP_INLINE_VISIBILITY
1540    basic_string& insert(size_type __pos1, const basic_string& __str);
1541    basic_string& insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n=npos);
1542    basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
1543    basic_string& insert(size_type __pos, const value_type* __s);
1544    basic_string& insert(size_type __pos, size_type __n, value_type __c);
1545    iterator      insert(const_iterator __pos, value_type __c);
1546    _LIBCPP_INLINE_VISIBILITY
1547    iterator      insert(const_iterator __pos, size_type __n, value_type __c);
1548    template<class _InputIterator>
1549        typename enable_if
1550        <
1551             __is_input_iterator  <_InputIterator>::value &&
1552            !__is_forward_iterator<_InputIterator>::value,
1553            iterator
1554        >::type
1555        insert(const_iterator __pos, _InputIterator __first, _InputIterator __last);
1556    template<class _ForwardIterator>
1557        typename enable_if
1558        <
1559            __is_forward_iterator<_ForwardIterator>::value,
1560            iterator
1561        >::type
1562        insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last);
1563#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1564    _LIBCPP_INLINE_VISIBILITY
1565    iterator insert(const_iterator __pos, initializer_list<value_type> __il)
1566                    {return insert(__pos, __il.begin(), __il.end());}
1567#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1568
1569    basic_string& erase(size_type __pos = 0, size_type __n = npos);
1570    _LIBCPP_INLINE_VISIBILITY
1571    iterator      erase(const_iterator __pos);
1572    _LIBCPP_INLINE_VISIBILITY
1573    iterator      erase(const_iterator __first, const_iterator __last);
1574
1575    _LIBCPP_INLINE_VISIBILITY
1576    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str);
1577    basic_string& replace(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos);
1578    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2);
1579    basic_string& replace(size_type __pos, size_type __n1, const value_type* __s);
1580    basic_string& replace(size_type __pos, size_type __n1, size_type __n2, value_type __c);
1581    _LIBCPP_INLINE_VISIBILITY
1582    basic_string& replace(const_iterator __i1, const_iterator __i2, const basic_string& __str);
1583    _LIBCPP_INLINE_VISIBILITY
1584    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n);
1585    _LIBCPP_INLINE_VISIBILITY
1586    basic_string& replace(const_iterator __i1, const_iterator __i2, const value_type* __s);
1587    _LIBCPP_INLINE_VISIBILITY
1588    basic_string& replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c);
1589    template<class _InputIterator>
1590        typename enable_if
1591        <
1592            __is_input_iterator<_InputIterator>::value,
1593            basic_string&
1594        >::type
1595        replace(const_iterator __i1, const_iterator __i2, _InputIterator __j1, _InputIterator __j2);
1596#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1597    _LIBCPP_INLINE_VISIBILITY
1598    basic_string& replace(const_iterator __i1, const_iterator __i2, initializer_list<value_type> __il)
1599        {return replace(__i1, __i2, __il.begin(), __il.end());}
1600#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1601
1602    size_type copy(value_type* __s, size_type __n, size_type __pos = 0) const;
1603    _LIBCPP_INLINE_VISIBILITY
1604    basic_string substr(size_type __pos = 0, size_type __n = npos) const;
1605
1606    _LIBCPP_INLINE_VISIBILITY
1607    void swap(basic_string& __str)
1608#if _LIBCPP_STD_VER >= 14
1609        _NOEXCEPT;
1610#else
1611        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
1612                    __is_nothrow_swappable<allocator_type>::value);
1613#endif
1614
1615    _LIBCPP_INLINE_VISIBILITY
1616    const value_type* c_str() const _NOEXCEPT {return data();}
1617    _LIBCPP_INLINE_VISIBILITY
1618    const value_type* data() const _NOEXCEPT  {return _VSTD::__to_raw_pointer(__get_pointer());}
1619
1620    _LIBCPP_INLINE_VISIBILITY
1621    allocator_type get_allocator() const _NOEXCEPT {return __alloc();}
1622
1623    _LIBCPP_INLINE_VISIBILITY
1624    size_type find(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1625    size_type find(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1626    _LIBCPP_INLINE_VISIBILITY
1627    size_type find(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1628    size_type find(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1629
1630    _LIBCPP_INLINE_VISIBILITY
1631    size_type rfind(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1632    size_type rfind(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1633    _LIBCPP_INLINE_VISIBILITY
1634    size_type rfind(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1635    size_type rfind(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1636
1637    _LIBCPP_INLINE_VISIBILITY
1638    size_type find_first_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1639    size_type find_first_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1640    _LIBCPP_INLINE_VISIBILITY
1641    size_type find_first_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1642    _LIBCPP_INLINE_VISIBILITY
1643    size_type find_first_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1644
1645    _LIBCPP_INLINE_VISIBILITY
1646    size_type find_last_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1647    size_type find_last_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1648    _LIBCPP_INLINE_VISIBILITY
1649    size_type find_last_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1650    _LIBCPP_INLINE_VISIBILITY
1651    size_type find_last_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1652
1653    _LIBCPP_INLINE_VISIBILITY
1654    size_type find_first_not_of(const basic_string& __str, size_type __pos = 0) const _NOEXCEPT;
1655    size_type find_first_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1656    _LIBCPP_INLINE_VISIBILITY
1657    size_type find_first_not_of(const value_type* __s, size_type __pos = 0) const _NOEXCEPT;
1658    _LIBCPP_INLINE_VISIBILITY
1659    size_type find_first_not_of(value_type __c, size_type __pos = 0) const _NOEXCEPT;
1660
1661    _LIBCPP_INLINE_VISIBILITY
1662    size_type find_last_not_of(const basic_string& __str, size_type __pos = npos) const _NOEXCEPT;
1663    size_type find_last_not_of(const value_type* __s, size_type __pos, size_type __n) const _NOEXCEPT;
1664    _LIBCPP_INLINE_VISIBILITY
1665    size_type find_last_not_of(const value_type* __s, size_type __pos = npos) const _NOEXCEPT;
1666    _LIBCPP_INLINE_VISIBILITY
1667    size_type find_last_not_of(value_type __c, size_type __pos = npos) const _NOEXCEPT;
1668
1669    _LIBCPP_INLINE_VISIBILITY
1670    int compare(const basic_string& __str) const _NOEXCEPT;
1671    _LIBCPP_INLINE_VISIBILITY
1672    int compare(size_type __pos1, size_type __n1, const basic_string& __str) const;
1673    int compare(size_type __pos1, size_type __n1, const basic_string& __str, size_type __pos2, size_type __n2=npos) const;
1674    int compare(const value_type* __s) const _NOEXCEPT;
1675    int compare(size_type __pos1, size_type __n1, const value_type* __s) const;
1676    int compare(size_type __pos1, size_type __n1, const value_type* __s, size_type __n2) const;
1677
1678    _LIBCPP_INLINE_VISIBILITY bool __invariants() const;
1679
1680    _LIBCPP_INLINE_VISIBILITY
1681    bool __is_long() const _NOEXCEPT
1682        {return bool(__r_.first().__s.__size_ & __short_mask);}
1683
1684#if _LIBCPP_DEBUG_LEVEL >= 2
1685
1686    bool __dereferenceable(const const_iterator* __i) const;
1687    bool __decrementable(const const_iterator* __i) const;
1688    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
1689    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
1690
1691#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1692
1693private:
1694    _LIBCPP_INLINE_VISIBILITY
1695    allocator_type& __alloc() _NOEXCEPT
1696        {return __r_.second();}
1697    _LIBCPP_INLINE_VISIBILITY
1698    const allocator_type& __alloc() const _NOEXCEPT
1699        {return __r_.second();}
1700
1701#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
1702
1703    _LIBCPP_INLINE_VISIBILITY
1704    void __set_short_size(size_type __s) _NOEXCEPT
1705#   if _LIBCPP_BIG_ENDIAN
1706        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1707#   else
1708        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1709#   endif
1710
1711    _LIBCPP_INLINE_VISIBILITY
1712    size_type __get_short_size() const _NOEXCEPT
1713#   if _LIBCPP_BIG_ENDIAN
1714        {return __r_.first().__s.__size_ >> 1;}
1715#   else
1716        {return __r_.first().__s.__size_;}
1717#   endif
1718
1719#else  // _LIBCPP_ALTERNATE_STRING_LAYOUT
1720
1721    _LIBCPP_INLINE_VISIBILITY
1722    void __set_short_size(size_type __s) _NOEXCEPT
1723#   if _LIBCPP_BIG_ENDIAN
1724        {__r_.first().__s.__size_ = (unsigned char)(__s);}
1725#   else
1726        {__r_.first().__s.__size_ = (unsigned char)(__s << 1);}
1727#   endif
1728
1729    _LIBCPP_INLINE_VISIBILITY
1730    size_type __get_short_size() const _NOEXCEPT
1731#   if _LIBCPP_BIG_ENDIAN
1732        {return __r_.first().__s.__size_;}
1733#   else
1734        {return __r_.first().__s.__size_ >> 1;}
1735#   endif
1736
1737#endif  // _LIBCPP_ALTERNATE_STRING_LAYOUT
1738
1739    _LIBCPP_INLINE_VISIBILITY
1740    void __set_long_size(size_type __s) _NOEXCEPT
1741        {__r_.first().__l.__size_ = __s;}
1742    _LIBCPP_INLINE_VISIBILITY
1743    size_type __get_long_size() const _NOEXCEPT
1744        {return __r_.first().__l.__size_;}
1745    _LIBCPP_INLINE_VISIBILITY
1746    void __set_size(size_type __s) _NOEXCEPT
1747        {if (__is_long()) __set_long_size(__s); else __set_short_size(__s);}
1748
1749    _LIBCPP_INLINE_VISIBILITY
1750    void __set_long_cap(size_type __s) _NOEXCEPT
1751        {__r_.first().__l.__cap_  = __long_mask | __s;}
1752    _LIBCPP_INLINE_VISIBILITY
1753    size_type __get_long_cap() const _NOEXCEPT
1754        {return __r_.first().__l.__cap_ & size_type(~__long_mask);}
1755
1756    _LIBCPP_INLINE_VISIBILITY
1757    void __set_long_pointer(pointer __p) _NOEXCEPT
1758        {__r_.first().__l.__data_ = __p;}
1759    _LIBCPP_INLINE_VISIBILITY
1760    pointer __get_long_pointer() _NOEXCEPT
1761        {return __r_.first().__l.__data_;}
1762    _LIBCPP_INLINE_VISIBILITY
1763    const_pointer __get_long_pointer() const _NOEXCEPT
1764        {return __r_.first().__l.__data_;}
1765    _LIBCPP_INLINE_VISIBILITY
1766    pointer __get_short_pointer() _NOEXCEPT
1767        {return pointer_traits<pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1768    _LIBCPP_INLINE_VISIBILITY
1769    const_pointer __get_short_pointer() const _NOEXCEPT
1770        {return pointer_traits<const_pointer>::pointer_to(__r_.first().__s.__data_[0]);}
1771    _LIBCPP_INLINE_VISIBILITY
1772    pointer __get_pointer() _NOEXCEPT
1773        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1774    _LIBCPP_INLINE_VISIBILITY
1775    const_pointer __get_pointer() const _NOEXCEPT
1776        {return __is_long() ? __get_long_pointer() : __get_short_pointer();}
1777
1778    _LIBCPP_INLINE_VISIBILITY
1779    void __zero() _NOEXCEPT
1780        {
1781            size_type (&__a)[__n_words] = __r_.first().__r.__words;
1782            for (unsigned __i = 0; __i < __n_words; ++__i)
1783                __a[__i] = 0;
1784        }
1785
1786    template <size_type __a> static
1787        _LIBCPP_INLINE_VISIBILITY
1788        size_type __align_it(size_type __s) _NOEXCEPT
1789            {return (__s + (__a-1)) & ~(__a-1);}
1790    enum {__alignment = 16};
1791    static _LIBCPP_INLINE_VISIBILITY
1792    size_type __recommend(size_type __s) _NOEXCEPT
1793        {return (__s < __min_cap ? static_cast<size_type>(__min_cap) :
1794                 __align_it<sizeof(value_type) < __alignment ?
1795                            __alignment/sizeof(value_type) : 1 > (__s+1)) - 1;}
1796
1797    void __init(const value_type* __s, size_type __sz, size_type __reserve);
1798    void __init(const value_type* __s, size_type __sz);
1799    void __init(size_type __n, value_type __c);
1800
1801    template <class _InputIterator>
1802    typename enable_if
1803    <
1804         __is_input_iterator  <_InputIterator>::value &&
1805        !__is_forward_iterator<_InputIterator>::value,
1806        void
1807    >::type
1808    __init(_InputIterator __first, _InputIterator __last);
1809
1810    template <class _ForwardIterator>
1811    typename enable_if
1812    <
1813        __is_forward_iterator<_ForwardIterator>::value,
1814        void
1815    >::type
1816    __init(_ForwardIterator __first, _ForwardIterator __last);
1817
1818    void __grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1819                   size_type __n_copy,  size_type __n_del,     size_type __n_add = 0);
1820    void __grow_by_and_replace(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
1821                               size_type __n_copy,  size_type __n_del,
1822                               size_type __n_add, const value_type* __p_new_stuff);
1823
1824    _LIBCPP_INLINE_VISIBILITY
1825    void __erase_to_end(size_type __pos);
1826
1827    _LIBCPP_INLINE_VISIBILITY
1828    void __copy_assign_alloc(const basic_string& __str)
1829        {__copy_assign_alloc(__str, integral_constant<bool,
1830                      __alloc_traits::propagate_on_container_copy_assignment::value>());}
1831
1832    _LIBCPP_INLINE_VISIBILITY
1833    void __copy_assign_alloc(const basic_string& __str, true_type)
1834        {
1835            if (__alloc() != __str.__alloc())
1836            {
1837                clear();
1838                shrink_to_fit();
1839            }
1840            __alloc() = __str.__alloc();
1841        }
1842
1843    _LIBCPP_INLINE_VISIBILITY
1844    void __copy_assign_alloc(const basic_string&, false_type) _NOEXCEPT
1845        {}
1846
1847#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1848    _LIBCPP_INLINE_VISIBILITY
1849    void __move_assign(basic_string& __str, false_type);
1850    _LIBCPP_INLINE_VISIBILITY
1851    void __move_assign(basic_string& __str, true_type)
1852        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
1853#endif
1854
1855    _LIBCPP_INLINE_VISIBILITY
1856    void
1857    __move_assign_alloc(basic_string& __str)
1858        _NOEXCEPT_(
1859            !__alloc_traits::propagate_on_container_move_assignment::value ||
1860            is_nothrow_move_assignable<allocator_type>::value)
1861    {__move_assign_alloc(__str, integral_constant<bool,
1862                      __alloc_traits::propagate_on_container_move_assignment::value>());}
1863
1864    _LIBCPP_INLINE_VISIBILITY
1865    void __move_assign_alloc(basic_string& __c, true_type)
1866        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1867        {
1868            __alloc() = _VSTD::move(__c.__alloc());
1869        }
1870
1871    _LIBCPP_INLINE_VISIBILITY
1872    void __move_assign_alloc(basic_string&, false_type)
1873        _NOEXCEPT
1874        {}
1875
1876    _LIBCPP_INLINE_VISIBILITY void __invalidate_all_iterators();
1877    _LIBCPP_INLINE_VISIBILITY void __invalidate_iterators_past(size_type);
1878
1879    friend basic_string operator+<>(const basic_string&, const basic_string&);
1880    friend basic_string operator+<>(const value_type*, const basic_string&);
1881    friend basic_string operator+<>(value_type, const basic_string&);
1882    friend basic_string operator+<>(const basic_string&, const value_type*);
1883    friend basic_string operator+<>(const basic_string&, value_type);
1884};
1885
1886template <class _CharT, class _Traits, class _Allocator>
1887inline _LIBCPP_INLINE_VISIBILITY
1888void
1889basic_string<_CharT, _Traits, _Allocator>::__invalidate_all_iterators()
1890{
1891#if _LIBCPP_DEBUG_LEVEL >= 2
1892    __get_db()->__invalidate_all(this);
1893#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1894}
1895
1896template <class _CharT, class _Traits, class _Allocator>
1897inline _LIBCPP_INLINE_VISIBILITY
1898void
1899basic_string<_CharT, _Traits, _Allocator>::__invalidate_iterators_past(size_type
1900#if _LIBCPP_DEBUG_LEVEL >= 2
1901                                                                        __pos
1902#endif
1903                                                                      )
1904{
1905#if _LIBCPP_DEBUG_LEVEL >= 2
1906    __c_node* __c = __get_db()->__find_c_and_lock(this);
1907    if (__c)
1908    {
1909        const_pointer __new_last = __get_pointer() + __pos;
1910        for (__i_node** __p = __c->end_; __p != __c->beg_; )
1911        {
1912            --__p;
1913            const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
1914            if (__i->base() > __new_last)
1915            {
1916                (*__p)->__c_ = nullptr;
1917                if (--__c->end_ != __p)
1918                    memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
1919            }
1920        }
1921        __get_db()->unlock();
1922    }
1923#endif  // _LIBCPP_DEBUG_LEVEL >= 2
1924}
1925
1926template <class _CharT, class _Traits, class _Allocator>
1927inline _LIBCPP_INLINE_VISIBILITY
1928basic_string<_CharT, _Traits, _Allocator>::basic_string()
1929    _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
1930{
1931#if _LIBCPP_DEBUG_LEVEL >= 2
1932    __get_db()->__insert_c(this);
1933#endif
1934    __zero();
1935}
1936
1937template <class _CharT, class _Traits, class _Allocator>
1938inline _LIBCPP_INLINE_VISIBILITY
1939basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __a)
1940#if _LIBCPP_STD_VER <= 14
1941        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
1942#else
1943        _NOEXCEPT
1944#endif
1945: __r_(__a)
1946{
1947#if _LIBCPP_DEBUG_LEVEL >= 2
1948    __get_db()->__insert_c(this);
1949#endif
1950    __zero();
1951}
1952
1953template <class _CharT, class _Traits, class _Allocator>
1954void
1955basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz, size_type __reserve)
1956{
1957    if (__reserve > max_size())
1958        this->__throw_length_error();
1959    pointer __p;
1960    if (__reserve < __min_cap)
1961    {
1962        __set_short_size(__sz);
1963        __p = __get_short_pointer();
1964    }
1965    else
1966    {
1967        size_type __cap = __recommend(__reserve);
1968        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1969        __set_long_pointer(__p);
1970        __set_long_cap(__cap+1);
1971        __set_long_size(__sz);
1972    }
1973    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
1974    traits_type::assign(__p[__sz], value_type());
1975}
1976
1977template <class _CharT, class _Traits, class _Allocator>
1978void
1979basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s, size_type __sz)
1980{
1981    if (__sz > max_size())
1982        this->__throw_length_error();
1983    pointer __p;
1984    if (__sz < __min_cap)
1985    {
1986        __set_short_size(__sz);
1987        __p = __get_short_pointer();
1988    }
1989    else
1990    {
1991        size_type __cap = __recommend(__sz);
1992        __p = __alloc_traits::allocate(__alloc(), __cap+1);
1993        __set_long_pointer(__p);
1994        __set_long_cap(__cap+1);
1995        __set_long_size(__sz);
1996    }
1997    traits_type::copy(_VSTD::__to_raw_pointer(__p), __s, __sz);
1998    traits_type::assign(__p[__sz], value_type());
1999}
2000
2001template <class _CharT, class _Traits, class _Allocator>
2002inline _LIBCPP_INLINE_VISIBILITY
2003basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s)
2004{
2005    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*) detected nullptr");
2006    __init(__s, traits_type::length(__s));
2007#if _LIBCPP_DEBUG_LEVEL >= 2
2008    __get_db()->__insert_c(this);
2009#endif
2010}
2011
2012template <class _CharT, class _Traits, class _Allocator>
2013inline _LIBCPP_INLINE_VISIBILITY
2014basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, const allocator_type& __a)
2015    : __r_(__a)
2016{
2017    _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*, allocator) detected nullptr");
2018    __init(__s, traits_type::length(__s));
2019#if _LIBCPP_DEBUG_LEVEL >= 2
2020    __get_db()->__insert_c(this);
2021#endif
2022}
2023
2024template <class _CharT, class _Traits, class _Allocator>
2025inline _LIBCPP_INLINE_VISIBILITY
2026basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n)
2027{
2028    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n) detected nullptr");
2029    __init(__s, __n);
2030#if _LIBCPP_DEBUG_LEVEL >= 2
2031    __get_db()->__insert_c(this);
2032#endif
2033}
2034
2035template <class _CharT, class _Traits, class _Allocator>
2036inline _LIBCPP_INLINE_VISIBILITY
2037basic_string<_CharT, _Traits, _Allocator>::basic_string(const value_type* __s, size_type __n, const allocator_type& __a)
2038    : __r_(__a)
2039{
2040    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n, allocator) detected nullptr");
2041    __init(__s, __n);
2042#if _LIBCPP_DEBUG_LEVEL >= 2
2043    __get_db()->__insert_c(this);
2044#endif
2045}
2046
2047template <class _CharT, class _Traits, class _Allocator>
2048basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str)
2049    : __r_(__alloc_traits::select_on_container_copy_construction(__str.__alloc()))
2050{
2051    if (!__str.__is_long())
2052        __r_.first().__r = __str.__r_.first().__r;
2053    else
2054        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
2055#if _LIBCPP_DEBUG_LEVEL >= 2
2056    __get_db()->__insert_c(this);
2057#endif
2058}
2059
2060template <class _CharT, class _Traits, class _Allocator>
2061basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, const allocator_type& __a)
2062    : __r_(__a)
2063{
2064    if (!__str.__is_long())
2065        __r_.first().__r = __str.__r_.first().__r;
2066    else
2067        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
2068#if _LIBCPP_DEBUG_LEVEL >= 2
2069    __get_db()->__insert_c(this);
2070#endif
2071}
2072
2073#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2074
2075template <class _CharT, class _Traits, class _Allocator>
2076inline _LIBCPP_INLINE_VISIBILITY
2077basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str)
2078#if _LIBCPP_STD_VER <= 14
2079        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
2080#else
2081        _NOEXCEPT
2082#endif
2083    : __r_(_VSTD::move(__str.__r_))
2084{
2085    __str.__zero();
2086#if _LIBCPP_DEBUG_LEVEL >= 2
2087    __get_db()->__insert_c(this);
2088    if (__is_long())
2089        __get_db()->swap(this, &__str);
2090#endif
2091}
2092
2093template <class _CharT, class _Traits, class _Allocator>
2094inline _LIBCPP_INLINE_VISIBILITY
2095basic_string<_CharT, _Traits, _Allocator>::basic_string(basic_string&& __str, const allocator_type& __a)
2096    : __r_(__a)
2097{
2098    if (__str.__is_long() && __a != __str.__alloc()) // copy, not move
2099        __init(_VSTD::__to_raw_pointer(__str.__get_long_pointer()), __str.__get_long_size());
2100    else
2101    {
2102        __r_.first().__r = __str.__r_.first().__r;
2103        __str.__zero();
2104    }
2105#if _LIBCPP_DEBUG_LEVEL >= 2
2106    __get_db()->__insert_c(this);
2107    if (__is_long())
2108        __get_db()->swap(this, &__str);
2109#endif
2110}
2111
2112#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2113
2114template <class _CharT, class _Traits, class _Allocator>
2115void
2116basic_string<_CharT, _Traits, _Allocator>::__init(size_type __n, value_type __c)
2117{
2118    if (__n > max_size())
2119        this->__throw_length_error();
2120    pointer __p;
2121    if (__n < __min_cap)
2122    {
2123        __set_short_size(__n);
2124        __p = __get_short_pointer();
2125    }
2126    else
2127    {
2128        size_type __cap = __recommend(__n);
2129        __p = __alloc_traits::allocate(__alloc(), __cap+1);
2130        __set_long_pointer(__p);
2131        __set_long_cap(__cap+1);
2132        __set_long_size(__n);
2133    }
2134    traits_type::assign(_VSTD::__to_raw_pointer(__p), __n, __c);
2135    traits_type::assign(__p[__n], value_type());
2136}
2137
2138template <class _CharT, class _Traits, class _Allocator>
2139inline _LIBCPP_INLINE_VISIBILITY
2140basic_string<_CharT, _Traits, _Allocator>::basic_string(size_type __n, value_type __c)
2141{
2142    __init(__n, __c);
2143#if _LIBCPP_DEBUG_LEVEL >= 2
2144    __get_db()->__insert_c(this);
2145#endif
2146}
2147
2148template <class _CharT, class _Traits, class _Allocator>
2149inline _LIBCPP_INLINE_VISIBILITY
2150basic_string<_CharT, _Traits, _Allocator>::basic_string(size_type __n, value_type __c, const allocator_type& __a)
2151    : __r_(__a)
2152{
2153    __init(__n, __c);
2154#if _LIBCPP_DEBUG_LEVEL >= 2
2155    __get_db()->__insert_c(this);
2156#endif
2157}
2158
2159template <class _CharT, class _Traits, class _Allocator>
2160basic_string<_CharT, _Traits, _Allocator>::basic_string(const basic_string& __str, size_type __pos, size_type __n,
2161                                                        const allocator_type& __a)
2162    : __r_(__a)
2163{
2164    size_type __str_sz = __str.size();
2165    if (__pos > __str_sz)
2166        this->__throw_out_of_range();
2167    __init(__str.data() + __pos, _VSTD::min(__n, __str_sz - __pos));
2168#if _LIBCPP_DEBUG_LEVEL >= 2
2169    __get_db()->__insert_c(this);
2170#endif
2171}
2172
2173template <class _CharT, class _Traits, class _Allocator>
2174template <class _InputIterator>
2175typename enable_if
2176<
2177     __is_input_iterator  <_InputIterator>::value &&
2178    !__is_forward_iterator<_InputIterator>::value,
2179    void
2180>::type
2181basic_string<_CharT, _Traits, _Allocator>::__init(_InputIterator __first, _InputIterator __last)
2182{
2183    __zero();
2184#ifndef _LIBCPP_NO_EXCEPTIONS
2185    try
2186    {
2187#endif  // _LIBCPP_NO_EXCEPTIONS
2188    for (; __first != __last; ++__first)
2189        push_back(*__first);
2190#ifndef _LIBCPP_NO_EXCEPTIONS
2191    }
2192    catch (...)
2193    {
2194        if (__is_long())
2195            __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
2196        throw;
2197    }
2198#endif  // _LIBCPP_NO_EXCEPTIONS
2199}
2200
2201template <class _CharT, class _Traits, class _Allocator>
2202template <class _ForwardIterator>
2203typename enable_if
2204<
2205    __is_forward_iterator<_ForwardIterator>::value,
2206    void
2207>::type
2208basic_string<_CharT, _Traits, _Allocator>::__init(_ForwardIterator __first, _ForwardIterator __last)
2209{
2210    size_type __sz = static_cast<size_type>(_VSTD::distance(__first, __last));
2211    if (__sz > max_size())
2212        this->__throw_length_error();
2213    pointer __p;
2214    if (__sz < __min_cap)
2215    {
2216        __set_short_size(__sz);
2217        __p = __get_short_pointer();
2218    }
2219    else
2220    {
2221        size_type __cap = __recommend(__sz);
2222        __p = __alloc_traits::allocate(__alloc(), __cap+1);
2223        __set_long_pointer(__p);
2224        __set_long_cap(__cap+1);
2225        __set_long_size(__sz);
2226    }
2227    for (; __first != __last; ++__first, (void) ++__p)
2228        traits_type::assign(*__p, *__first);
2229    traits_type::assign(*__p, value_type());
2230}
2231
2232template <class _CharT, class _Traits, class _Allocator>
2233template<class _InputIterator>
2234inline _LIBCPP_INLINE_VISIBILITY
2235basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last)
2236{
2237    __init(__first, __last);
2238#if _LIBCPP_DEBUG_LEVEL >= 2
2239    __get_db()->__insert_c(this);
2240#endif
2241}
2242
2243template <class _CharT, class _Traits, class _Allocator>
2244template<class _InputIterator>
2245inline _LIBCPP_INLINE_VISIBILITY
2246basic_string<_CharT, _Traits, _Allocator>::basic_string(_InputIterator __first, _InputIterator __last,
2247                                                        const allocator_type& __a)
2248    : __r_(__a)
2249{
2250    __init(__first, __last);
2251#if _LIBCPP_DEBUG_LEVEL >= 2
2252    __get_db()->__insert_c(this);
2253#endif
2254}
2255
2256#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
2257
2258template <class _CharT, class _Traits, class _Allocator>
2259inline _LIBCPP_INLINE_VISIBILITY
2260basic_string<_CharT, _Traits, _Allocator>::basic_string(initializer_list<value_type> __il)
2261{
2262    __init(__il.begin(), __il.end());
2263#if _LIBCPP_DEBUG_LEVEL >= 2
2264    __get_db()->__insert_c(this);
2265#endif
2266}
2267
2268template <class _CharT, class _Traits, class _Allocator>
2269inline _LIBCPP_INLINE_VISIBILITY
2270basic_string<_CharT, _Traits, _Allocator>::basic_string(initializer_list<value_type> __il, const allocator_type& __a)
2271    : __r_(__a)
2272{
2273    __init(__il.begin(), __il.end());
2274#if _LIBCPP_DEBUG_LEVEL >= 2
2275    __get_db()->__insert_c(this);
2276#endif
2277}
2278
2279#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
2280
2281template <class _CharT, class _Traits, class _Allocator>
2282basic_string<_CharT, _Traits, _Allocator>::~basic_string()
2283{
2284#if _LIBCPP_DEBUG_LEVEL >= 2
2285    __get_db()->__erase_c(this);
2286#endif
2287    if (__is_long())
2288        __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
2289}
2290
2291template <class _CharT, class _Traits, class _Allocator>
2292void
2293basic_string<_CharT, _Traits, _Allocator>::__grow_by_and_replace
2294    (size_type __old_cap, size_type __delta_cap, size_type __old_sz,
2295     size_type __n_copy,  size_type __n_del,     size_type __n_add, const value_type* __p_new_stuff)
2296{
2297    size_type __ms = max_size();
2298    if (__delta_cap > __ms - __old_cap - 1)
2299        this->__throw_length_error();
2300    pointer __old_p = __get_pointer();
2301    size_type __cap = __old_cap < __ms / 2 - __alignment ?
2302                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
2303                          __ms - 1;
2304    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
2305    __invalidate_all_iterators();
2306    if (__n_copy != 0)
2307        traits_type::copy(_VSTD::__to_raw_pointer(__p),
2308                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
2309    if (__n_add != 0)
2310        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy, __p_new_stuff, __n_add);
2311    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
2312    if (__sec_cp_sz != 0)
2313        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
2314                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del, __sec_cp_sz);
2315    if (__old_cap+1 != __min_cap)
2316        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
2317    __set_long_pointer(__p);
2318    __set_long_cap(__cap+1);
2319    __old_sz = __n_copy + __n_add + __sec_cp_sz;
2320    __set_long_size(__old_sz);
2321    traits_type::assign(__p[__old_sz], value_type());
2322}
2323
2324template <class _CharT, class _Traits, class _Allocator>
2325void
2326basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
2327                                                     size_type __n_copy,  size_type __n_del,     size_type __n_add)
2328{
2329    size_type __ms = max_size();
2330    if (__delta_cap > __ms - __old_cap)
2331        this->__throw_length_error();
2332    pointer __old_p = __get_pointer();
2333    size_type __cap = __old_cap < __ms / 2 - __alignment ?
2334                          __recommend(_VSTD::max(__old_cap + __delta_cap, 2 * __old_cap)) :
2335                          __ms - 1;
2336    pointer __p = __alloc_traits::allocate(__alloc(), __cap+1);
2337    __invalidate_all_iterators();
2338    if (__n_copy != 0)
2339        traits_type::copy(_VSTD::__to_raw_pointer(__p),
2340                          _VSTD::__to_raw_pointer(__old_p), __n_copy);
2341    size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
2342    if (__sec_cp_sz != 0)
2343        traits_type::copy(_VSTD::__to_raw_pointer(__p) + __n_copy + __n_add,
2344                          _VSTD::__to_raw_pointer(__old_p) + __n_copy + __n_del,
2345                          __sec_cp_sz);
2346    if (__old_cap+1 != __min_cap)
2347        __alloc_traits::deallocate(__alloc(), __old_p, __old_cap+1);
2348    __set_long_pointer(__p);
2349    __set_long_cap(__cap+1);
2350}
2351
2352// assign
2353
2354template <class _CharT, class _Traits, class _Allocator>
2355basic_string<_CharT, _Traits, _Allocator>&
2356basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n)
2357{
2358    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::assign received nullptr");
2359    size_type __cap = capacity();
2360    if (__cap >= __n)
2361    {
2362        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2363        traits_type::move(__p, __s, __n);
2364        traits_type::assign(__p[__n], value_type());
2365        __set_size(__n);
2366        __invalidate_iterators_past(__n);
2367    }
2368    else
2369    {
2370        size_type __sz = size();
2371        __grow_by_and_replace(__cap, __n - __cap, __sz, 0, __sz, __n, __s);
2372    }
2373    return *this;
2374}
2375
2376template <class _CharT, class _Traits, class _Allocator>
2377basic_string<_CharT, _Traits, _Allocator>&
2378basic_string<_CharT, _Traits, _Allocator>::assign(size_type __n, value_type __c)
2379{
2380    size_type __cap = capacity();
2381    if (__cap < __n)
2382    {
2383        size_type __sz = size();
2384        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
2385    }
2386    else
2387        __invalidate_iterators_past(__n);
2388    value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2389    traits_type::assign(__p, __n, __c);
2390    traits_type::assign(__p[__n], value_type());
2391    __set_size(__n);
2392    return *this;
2393}
2394
2395template <class _CharT, class _Traits, class _Allocator>
2396basic_string<_CharT, _Traits, _Allocator>&
2397basic_string<_CharT, _Traits, _Allocator>::operator=(value_type __c)
2398{
2399    pointer __p;
2400    if (__is_long())
2401    {
2402        __p = __get_long_pointer();
2403        __set_long_size(1);
2404    }
2405    else
2406    {
2407        __p = __get_short_pointer();
2408        __set_short_size(1);
2409    }
2410    traits_type::assign(*__p, __c);
2411    traits_type::assign(*++__p, value_type());
2412    __invalidate_iterators_past(1);
2413    return *this;
2414}
2415
2416template <class _CharT, class _Traits, class _Allocator>
2417basic_string<_CharT, _Traits, _Allocator>&
2418basic_string<_CharT, _Traits, _Allocator>::operator=(const basic_string& __str)
2419{
2420    if (this != &__str)
2421    {
2422        __copy_assign_alloc(__str);
2423        assign(__str);
2424    }
2425    return *this;
2426}
2427
2428#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2429
2430template <class _CharT, class _Traits, class _Allocator>
2431inline _LIBCPP_INLINE_VISIBILITY
2432void
2433basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, false_type)
2434{
2435    if (__alloc() != __str.__alloc())
2436        assign(__str);
2437    else
2438        __move_assign(__str, true_type());
2439}
2440
2441template <class _CharT, class _Traits, class _Allocator>
2442inline _LIBCPP_INLINE_VISIBILITY
2443void
2444basic_string<_CharT, _Traits, _Allocator>::__move_assign(basic_string& __str, true_type)
2445    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
2446{
2447    clear();
2448    shrink_to_fit();
2449    __r_.first() = __str.__r_.first();
2450    __move_assign_alloc(__str);
2451    __str.__zero();
2452}
2453
2454template <class _CharT, class _Traits, class _Allocator>
2455inline _LIBCPP_INLINE_VISIBILITY
2456basic_string<_CharT, _Traits, _Allocator>&
2457basic_string<_CharT, _Traits, _Allocator>::operator=(basic_string&& __str)
2458    _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
2459               is_nothrow_move_assignable<allocator_type>::value)
2460{
2461    __move_assign(__str, integral_constant<bool,
2462          __alloc_traits::propagate_on_container_move_assignment::value>());
2463    return *this;
2464}
2465
2466#endif
2467
2468template <class _CharT, class _Traits, class _Allocator>
2469template<class _InputIterator>
2470typename enable_if
2471<
2472     __is_input_iterator  <_InputIterator>::value &&
2473    !__is_forward_iterator<_InputIterator>::value,
2474    basic_string<_CharT, _Traits, _Allocator>&
2475>::type
2476basic_string<_CharT, _Traits, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
2477{
2478    clear();
2479    for (; __first != __last; ++__first)
2480        push_back(*__first);
2481    return *this;
2482}
2483
2484template <class _CharT, class _Traits, class _Allocator>
2485template<class _ForwardIterator>
2486typename enable_if
2487<
2488    __is_forward_iterator<_ForwardIterator>::value,
2489    basic_string<_CharT, _Traits, _Allocator>&
2490>::type
2491basic_string<_CharT, _Traits, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last)
2492{
2493    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2494    size_type __cap = capacity();
2495    if (__cap < __n)
2496    {
2497        size_type __sz = size();
2498        __grow_by(__cap, __n - __cap, __sz, 0, __sz);
2499    }
2500    else
2501        __invalidate_iterators_past(__n);
2502    pointer __p = __get_pointer();
2503    for (; __first != __last; ++__first, ++__p)
2504        traits_type::assign(*__p, *__first);
2505    traits_type::assign(*__p, value_type());
2506    __set_size(__n);
2507    return *this;
2508}
2509
2510template <class _CharT, class _Traits, class _Allocator>
2511inline _LIBCPP_INLINE_VISIBILITY
2512basic_string<_CharT, _Traits, _Allocator>&
2513basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str)
2514{
2515    return assign(__str.data(), __str.size());
2516}
2517
2518template <class _CharT, class _Traits, class _Allocator>
2519basic_string<_CharT, _Traits, _Allocator>&
2520basic_string<_CharT, _Traits, _Allocator>::assign(const basic_string& __str, size_type __pos, size_type __n)
2521{
2522    size_type __sz = __str.size();
2523    if (__pos > __sz)
2524        this->__throw_out_of_range();
2525    return assign(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2526}
2527
2528template <class _CharT, class _Traits, class _Allocator>
2529basic_string<_CharT, _Traits, _Allocator>&
2530basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s)
2531{
2532    _LIBCPP_ASSERT(__s != nullptr, "string::assign received nullptr");
2533    return assign(__s, traits_type::length(__s));
2534}
2535
2536// append
2537
2538template <class _CharT, class _Traits, class _Allocator>
2539basic_string<_CharT, _Traits, _Allocator>&
2540basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s, size_type __n)
2541{
2542    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::append received nullptr");
2543    size_type __cap = capacity();
2544    size_type __sz = size();
2545    if (__cap - __sz >= __n)
2546    {
2547        if (__n)
2548        {
2549            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2550            traits_type::copy(__p + __sz, __s, __n);
2551            __sz += __n;
2552            __set_size(__sz);
2553            traits_type::assign(__p[__sz], value_type());
2554        }
2555    }
2556    else
2557        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __sz, 0, __n, __s);
2558    return *this;
2559}
2560
2561template <class _CharT, class _Traits, class _Allocator>
2562basic_string<_CharT, _Traits, _Allocator>&
2563basic_string<_CharT, _Traits, _Allocator>::append(size_type __n, value_type __c)
2564{
2565    if (__n)
2566    {
2567        size_type __cap = capacity();
2568        size_type __sz = size();
2569        if (__cap - __sz < __n)
2570            __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2571        pointer __p = __get_pointer();
2572        traits_type::assign(_VSTD::__to_raw_pointer(__p) + __sz, __n, __c);
2573        __sz += __n;
2574        __set_size(__sz);
2575        traits_type::assign(__p[__sz], value_type());
2576    }
2577    return *this;
2578}
2579
2580template <class _CharT, class _Traits, class _Allocator>
2581void
2582basic_string<_CharT, _Traits, _Allocator>::push_back(value_type __c)
2583{
2584    bool __is_short = !__is_long();
2585    size_type __cap;
2586    size_type __sz;
2587    if (__is_short)
2588    {
2589        __cap = __min_cap - 1;
2590        __sz = __get_short_size();
2591    }
2592    else
2593    {
2594        __cap = __get_long_cap() - 1;
2595        __sz = __get_long_size();
2596    }
2597    if (__sz == __cap)
2598    {
2599        __grow_by(__cap, 1, __sz, __sz, 0);
2600        __is_short = !__is_long();
2601    }
2602    pointer __p;
2603    if (__is_short)
2604    {
2605        __p = __get_short_pointer() + __sz;
2606        __set_short_size(__sz+1);
2607    }
2608    else
2609    {
2610        __p = __get_long_pointer() + __sz;
2611        __set_long_size(__sz+1);
2612    }
2613    traits_type::assign(*__p, __c);
2614    traits_type::assign(*++__p, value_type());
2615}
2616
2617template <class _CharT, class _Traits, class _Allocator>
2618template<class _InputIterator>
2619typename enable_if
2620<
2621     __is_input_iterator  <_InputIterator>::value &&
2622    !__is_forward_iterator<_InputIterator>::value,
2623    basic_string<_CharT, _Traits, _Allocator>&
2624>::type
2625basic_string<_CharT, _Traits, _Allocator>::append(_InputIterator __first, _InputIterator __last)
2626{
2627    for (; __first != __last; ++__first)
2628        push_back(*__first);
2629    return *this;
2630}
2631
2632template <class _CharT, class _Traits, class _Allocator>
2633template<class _ForwardIterator>
2634typename enable_if
2635<
2636    __is_forward_iterator<_ForwardIterator>::value,
2637    basic_string<_CharT, _Traits, _Allocator>&
2638>::type
2639basic_string<_CharT, _Traits, _Allocator>::append(_ForwardIterator __first, _ForwardIterator __last)
2640{
2641    size_type __sz = size();
2642    size_type __cap = capacity();
2643    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2644    if (__n)
2645    {
2646        if (__cap - __sz < __n)
2647            __grow_by(__cap, __sz + __n - __cap, __sz, __sz, 0);
2648        pointer __p = __get_pointer() + __sz;
2649        for (; __first != __last; ++__p, ++__first)
2650            traits_type::assign(*__p, *__first);
2651        traits_type::assign(*__p, value_type());
2652        __set_size(__sz + __n);
2653    }
2654    return *this;
2655}
2656
2657template <class _CharT, class _Traits, class _Allocator>
2658inline _LIBCPP_INLINE_VISIBILITY
2659basic_string<_CharT, _Traits, _Allocator>&
2660basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str)
2661{
2662    return append(__str.data(), __str.size());
2663}
2664
2665template <class _CharT, class _Traits, class _Allocator>
2666basic_string<_CharT, _Traits, _Allocator>&
2667basic_string<_CharT, _Traits, _Allocator>::append(const basic_string& __str, size_type __pos, size_type __n)
2668{
2669    size_type __sz = __str.size();
2670    if (__pos > __sz)
2671        this->__throw_out_of_range();
2672    return append(__str.data() + __pos, _VSTD::min(__n, __sz - __pos));
2673}
2674
2675template <class _CharT, class _Traits, class _Allocator>
2676basic_string<_CharT, _Traits, _Allocator>&
2677basic_string<_CharT, _Traits, _Allocator>::append(const value_type* __s)
2678{
2679    _LIBCPP_ASSERT(__s != nullptr, "string::append received nullptr");
2680    return append(__s, traits_type::length(__s));
2681}
2682
2683// insert
2684
2685template <class _CharT, class _Traits, class _Allocator>
2686basic_string<_CharT, _Traits, _Allocator>&
2687basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s, size_type __n)
2688{
2689    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::insert received nullptr");
2690    size_type __sz = size();
2691    if (__pos > __sz)
2692        this->__throw_out_of_range();
2693    size_type __cap = capacity();
2694    if (__cap - __sz >= __n)
2695    {
2696        if (__n)
2697        {
2698            value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2699            size_type __n_move = __sz - __pos;
2700            if (__n_move != 0)
2701            {
2702                if (__p + __pos <= __s && __s < __p + __sz)
2703                    __s += __n;
2704                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2705            }
2706            traits_type::move(__p + __pos, __s, __n);
2707            __sz += __n;
2708            __set_size(__sz);
2709            traits_type::assign(__p[__sz], value_type());
2710        }
2711    }
2712    else
2713        __grow_by_and_replace(__cap, __sz + __n - __cap, __sz, __pos, 0, __n, __s);
2714    return *this;
2715}
2716
2717template <class _CharT, class _Traits, class _Allocator>
2718basic_string<_CharT, _Traits, _Allocator>&
2719basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n, value_type __c)
2720{
2721    size_type __sz = size();
2722    if (__pos > __sz)
2723        this->__throw_out_of_range();
2724    if (__n)
2725    {
2726        size_type __cap = capacity();
2727        value_type* __p;
2728        if (__cap - __sz >= __n)
2729        {
2730            __p = _VSTD::__to_raw_pointer(__get_pointer());
2731            size_type __n_move = __sz - __pos;
2732            if (__n_move != 0)
2733                traits_type::move(__p + __pos + __n, __p + __pos, __n_move);
2734        }
2735        else
2736        {
2737            __grow_by(__cap, __sz + __n - __cap, __sz, __pos, 0, __n);
2738            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2739        }
2740        traits_type::assign(__p + __pos, __n, __c);
2741        __sz += __n;
2742        __set_size(__sz);
2743        traits_type::assign(__p[__sz], value_type());
2744    }
2745    return *this;
2746}
2747
2748template <class _CharT, class _Traits, class _Allocator>
2749template<class _InputIterator>
2750typename enable_if
2751<
2752     __is_input_iterator  <_InputIterator>::value &&
2753    !__is_forward_iterator<_InputIterator>::value,
2754    typename basic_string<_CharT, _Traits, _Allocator>::iterator
2755>::type
2756basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _InputIterator __first, _InputIterator __last)
2757{
2758#if _LIBCPP_DEBUG_LEVEL >= 2
2759    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2760        "string::insert(iterator, range) called with an iterator not"
2761        " referring to this string");
2762#endif
2763    size_type __old_sz = size();
2764    difference_type __ip = __pos - begin();
2765    for (; __first != __last; ++__first)
2766        push_back(*__first);
2767    pointer __p = __get_pointer();
2768    _VSTD::rotate(__p + __ip, __p + __old_sz, __p + size());
2769#if _LIBCPP_DEBUG_LEVEL >= 2
2770    return iterator(this, __p + __ip);
2771#else
2772    return iterator(__p + __ip);
2773#endif
2774}
2775
2776template <class _CharT, class _Traits, class _Allocator>
2777template<class _ForwardIterator>
2778typename enable_if
2779<
2780    __is_forward_iterator<_ForwardIterator>::value,
2781    typename basic_string<_CharT, _Traits, _Allocator>::iterator
2782>::type
2783basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last)
2784{
2785#if _LIBCPP_DEBUG_LEVEL >= 2
2786    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2787        "string::insert(iterator, range) called with an iterator not"
2788        " referring to this string");
2789#endif
2790    size_type __ip = static_cast<size_type>(__pos - begin());
2791    size_type __sz = size();
2792    size_type __cap = capacity();
2793    size_type __n = static_cast<size_type>(_VSTD::distance(__first, __last));
2794    if (__n)
2795    {
2796        value_type* __p;
2797        if (__cap - __sz >= __n)
2798        {
2799            __p = _VSTD::__to_raw_pointer(__get_pointer());
2800            size_type __n_move = __sz - __ip;
2801            if (__n_move != 0)
2802                traits_type::move(__p + __ip + __n, __p + __ip, __n_move);
2803        }
2804        else
2805        {
2806            __grow_by(__cap, __sz + __n - __cap, __sz, __ip, 0, __n);
2807            __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2808        }
2809        __sz += __n;
2810        __set_size(__sz);
2811        traits_type::assign(__p[__sz], value_type());
2812        for (__p += __ip; __first != __last; ++__p, ++__first)
2813            traits_type::assign(*__p, *__first);
2814    }
2815    return begin() + __ip;
2816}
2817
2818template <class _CharT, class _Traits, class _Allocator>
2819inline _LIBCPP_INLINE_VISIBILITY
2820basic_string<_CharT, _Traits, _Allocator>&
2821basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str)
2822{
2823    return insert(__pos1, __str.data(), __str.size());
2824}
2825
2826template <class _CharT, class _Traits, class _Allocator>
2827basic_string<_CharT, _Traits, _Allocator>&
2828basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos1, const basic_string& __str,
2829                                                  size_type __pos2, size_type __n)
2830{
2831    size_type __str_sz = __str.size();
2832    if (__pos2 > __str_sz)
2833        this->__throw_out_of_range();
2834    return insert(__pos1, __str.data() + __pos2, _VSTD::min(__n, __str_sz - __pos2));
2835}
2836
2837template <class _CharT, class _Traits, class _Allocator>
2838basic_string<_CharT, _Traits, _Allocator>&
2839basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s)
2840{
2841    _LIBCPP_ASSERT(__s != nullptr, "string::insert received nullptr");
2842    return insert(__pos, __s, traits_type::length(__s));
2843}
2844
2845template <class _CharT, class _Traits, class _Allocator>
2846typename basic_string<_CharT, _Traits, _Allocator>::iterator
2847basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_type __c)
2848{
2849    size_type __ip = static_cast<size_type>(__pos - begin());
2850    size_type __sz = size();
2851    size_type __cap = capacity();
2852    value_type* __p;
2853    if (__cap == __sz)
2854    {
2855        __grow_by(__cap, 1, __sz, __ip, 0, 1);
2856        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2857    }
2858    else
2859    {
2860        __p = _VSTD::__to_raw_pointer(__get_pointer());
2861        size_type __n_move = __sz - __ip;
2862        if (__n_move != 0)
2863            traits_type::move(__p + __ip + 1, __p + __ip, __n_move);
2864    }
2865    traits_type::assign(__p[__ip], __c);
2866    traits_type::assign(__p[++__sz], value_type());
2867    __set_size(__sz);
2868    return begin() + static_cast<difference_type>(__ip);
2869}
2870
2871template <class _CharT, class _Traits, class _Allocator>
2872inline _LIBCPP_INLINE_VISIBILITY
2873typename basic_string<_CharT, _Traits, _Allocator>::iterator
2874basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, size_type __n, value_type __c)
2875{
2876#if _LIBCPP_DEBUG_LEVEL >= 2
2877    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
2878        "string::insert(iterator, n, value) called with an iterator not"
2879        " referring to this string");
2880#endif
2881    difference_type __p = __pos - begin();
2882    insert(static_cast<size_type>(__p), __n, __c);
2883    return begin() + __p;
2884}
2885
2886// replace
2887
2888template <class _CharT, class _Traits, class _Allocator>
2889basic_string<_CharT, _Traits, _Allocator>&
2890basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s, size_type __n2)
2891{
2892    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::replace received nullptr");
2893    size_type __sz = size();
2894    if (__pos > __sz)
2895        this->__throw_out_of_range();
2896    __n1 = _VSTD::min(__n1, __sz - __pos);
2897    size_type __cap = capacity();
2898    if (__cap - __sz + __n1 >= __n2)
2899    {
2900        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
2901        if (__n1 != __n2)
2902        {
2903            size_type __n_move = __sz - __pos - __n1;
2904            if (__n_move != 0)
2905            {
2906                if (__n1 > __n2)
2907                {
2908                    traits_type::move(__p + __pos, __s, __n2);
2909                    traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2910                    goto __finish;
2911                }
2912                if (__p + __pos < __s && __s < __p + __sz)
2913                {
2914                    if (__p + __pos + __n1 <= __s)
2915                        __s += __n2 - __n1;
2916                    else // __p + __pos < __s < __p + __pos + __n1
2917                    {
2918                        traits_type::move(__p + __pos, __s, __n1);
2919                        __pos += __n1;
2920                        __s += __n2;
2921                        __n2 -= __n1;
2922                        __n1 = 0;
2923                    }
2924                }
2925                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2926            }
2927        }
2928        traits_type::move(__p + __pos, __s, __n2);
2929__finish:
2930        __sz += __n2 - __n1;
2931        __set_size(__sz);
2932        __invalidate_iterators_past(__sz);
2933        traits_type::assign(__p[__sz], value_type());
2934    }
2935    else
2936        __grow_by_and_replace(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2, __s);
2937    return *this;
2938}
2939
2940template <class _CharT, class _Traits, class _Allocator>
2941basic_string<_CharT, _Traits, _Allocator>&
2942basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, size_type __n2, value_type __c)
2943{
2944    size_type __sz = size();
2945    if (__pos > __sz)
2946        this->__throw_out_of_range();
2947    __n1 = _VSTD::min(__n1, __sz - __pos);
2948    size_type __cap = capacity();
2949    value_type* __p;
2950    if (__cap - __sz + __n1 >= __n2)
2951    {
2952        __p = _VSTD::__to_raw_pointer(__get_pointer());
2953        if (__n1 != __n2)
2954        {
2955            size_type __n_move = __sz - __pos - __n1;
2956            if (__n_move != 0)
2957                traits_type::move(__p + __pos + __n2, __p + __pos + __n1, __n_move);
2958        }
2959    }
2960    else
2961    {
2962        __grow_by(__cap, __sz - __n1 + __n2 - __cap, __sz, __pos, __n1, __n2);
2963        __p = _VSTD::__to_raw_pointer(__get_long_pointer());
2964    }
2965    traits_type::assign(__p + __pos, __n2, __c);
2966    __sz += __n2 - __n1;
2967    __set_size(__sz);
2968    __invalidate_iterators_past(__sz);
2969    traits_type::assign(__p[__sz], value_type());
2970    return *this;
2971}
2972
2973template <class _CharT, class _Traits, class _Allocator>
2974template<class _InputIterator>
2975typename enable_if
2976<
2977    __is_input_iterator<_InputIterator>::value,
2978    basic_string<_CharT, _Traits, _Allocator>&
2979>::type
2980basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2,
2981                                                   _InputIterator __j1, _InputIterator __j2)
2982{
2983    for (; true; ++__i1, ++__j1)
2984    {
2985        if (__i1 == __i2)
2986        {
2987            if (__j1 != __j2)
2988                insert(__i1, __j1, __j2);
2989            break;
2990        }
2991        if (__j1 == __j2)
2992        {
2993            erase(__i1, __i2);
2994            break;
2995        }
2996        traits_type::assign(const_cast<value_type&>(*__i1), *__j1);
2997    }
2998    return *this;
2999}
3000
3001template <class _CharT, class _Traits, class _Allocator>
3002inline _LIBCPP_INLINE_VISIBILITY
3003basic_string<_CharT, _Traits, _Allocator>&
3004basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str)
3005{
3006    return replace(__pos1, __n1, __str.data(), __str.size());
3007}
3008
3009template <class _CharT, class _Traits, class _Allocator>
3010basic_string<_CharT, _Traits, _Allocator>&
3011basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos1, size_type __n1, const basic_string& __str,
3012                                                   size_type __pos2, size_type __n2)
3013{
3014    size_type __str_sz = __str.size();
3015    if (__pos2 > __str_sz)
3016        this->__throw_out_of_range();
3017    return replace(__pos1, __n1, __str.data() + __pos2, _VSTD::min(__n2, __str_sz - __pos2));
3018}
3019
3020template <class _CharT, class _Traits, class _Allocator>
3021basic_string<_CharT, _Traits, _Allocator>&
3022basic_string<_CharT, _Traits, _Allocator>::replace(size_type __pos, size_type __n1, const value_type* __s)
3023{
3024    _LIBCPP_ASSERT(__s != nullptr, "string::replace received nullptr");
3025    return replace(__pos, __n1, __s, traits_type::length(__s));
3026}
3027
3028template <class _CharT, class _Traits, class _Allocator>
3029inline _LIBCPP_INLINE_VISIBILITY
3030basic_string<_CharT, _Traits, _Allocator>&
3031basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const basic_string& __str)
3032{
3033    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1),
3034                   __str.data(), __str.size());
3035}
3036
3037template <class _CharT, class _Traits, class _Allocator>
3038inline _LIBCPP_INLINE_VISIBILITY
3039basic_string<_CharT, _Traits, _Allocator>&
3040basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s, size_type __n)
3041{
3042    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s, __n);
3043}
3044
3045template <class _CharT, class _Traits, class _Allocator>
3046inline _LIBCPP_INLINE_VISIBILITY
3047basic_string<_CharT, _Traits, _Allocator>&
3048basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, const value_type* __s)
3049{
3050    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __s);
3051}
3052
3053template <class _CharT, class _Traits, class _Allocator>
3054inline _LIBCPP_INLINE_VISIBILITY
3055basic_string<_CharT, _Traits, _Allocator>&
3056basic_string<_CharT, _Traits, _Allocator>::replace(const_iterator __i1, const_iterator __i2, size_type __n, value_type __c)
3057{
3058    return replace(static_cast<size_type>(__i1 - begin()), static_cast<size_type>(__i2 - __i1), __n, __c);
3059}
3060
3061// erase
3062
3063template <class _CharT, class _Traits, class _Allocator>
3064basic_string<_CharT, _Traits, _Allocator>&
3065basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos, size_type __n)
3066{
3067    size_type __sz = size();
3068    if (__pos > __sz)
3069        this->__throw_out_of_range();
3070    if (__n)
3071    {
3072        value_type* __p = _VSTD::__to_raw_pointer(__get_pointer());
3073        __n = _VSTD::min(__n, __sz - __pos);
3074        size_type __n_move = __sz - __pos - __n;
3075        if (__n_move != 0)
3076            traits_type::move(__p + __pos, __p + __pos + __n, __n_move);
3077        __sz -= __n;
3078        __set_size(__sz);
3079        __invalidate_iterators_past(__sz);
3080        traits_type::assign(__p[__sz], value_type());
3081    }
3082    return *this;
3083}
3084
3085template <class _CharT, class _Traits, class _Allocator>
3086inline _LIBCPP_INLINE_VISIBILITY
3087typename basic_string<_CharT, _Traits, _Allocator>::iterator
3088basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __pos)
3089{
3090#if _LIBCPP_DEBUG_LEVEL >= 2
3091    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
3092        "string::erase(iterator) called with an iterator not"
3093        " referring to this string");
3094#endif
3095    _LIBCPP_ASSERT(__pos != end(),
3096        "string::erase(iterator) called with a non-dereferenceable iterator");
3097    iterator __b = begin();
3098    size_type __r = static_cast<size_type>(__pos - __b);
3099    erase(__r, 1);
3100    return __b + static_cast<difference_type>(__r);
3101}
3102
3103template <class _CharT, class _Traits, class _Allocator>
3104inline _LIBCPP_INLINE_VISIBILITY
3105typename basic_string<_CharT, _Traits, _Allocator>::iterator
3106basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __first, const_iterator __last)
3107{
3108#if _LIBCPP_DEBUG_LEVEL >= 2
3109    _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
3110        "string::erase(iterator,  iterator) called with an iterator not"
3111        " referring to this string");
3112#endif
3113    _LIBCPP_ASSERT(__first <= __last, "string::erase(first, last) called with invalid range");
3114    iterator __b = begin();
3115    size_type __r = static_cast<size_type>(__first - __b);
3116    erase(__r, static_cast<size_type>(__last - __first));
3117    return __b + static_cast<difference_type>(__r);
3118}
3119
3120template <class _CharT, class _Traits, class _Allocator>
3121inline _LIBCPP_INLINE_VISIBILITY
3122void
3123basic_string<_CharT, _Traits, _Allocator>::pop_back()
3124{
3125    _LIBCPP_ASSERT(!empty(), "string::pop_back(): string is already empty");
3126    size_type __sz;
3127    if (__is_long())
3128    {
3129        __sz = __get_long_size() - 1;
3130        __set_long_size(__sz);
3131        traits_type::assign(*(__get_long_pointer() + __sz), value_type());
3132    }
3133    else
3134    {
3135        __sz = __get_short_size() - 1;
3136        __set_short_size(__sz);
3137        traits_type::assign(*(__get_short_pointer() + __sz), value_type());
3138    }
3139    __invalidate_iterators_past(__sz);
3140}
3141
3142template <class _CharT, class _Traits, class _Allocator>
3143inline _LIBCPP_INLINE_VISIBILITY
3144void
3145basic_string<_CharT, _Traits, _Allocator>::clear() _NOEXCEPT
3146{
3147    __invalidate_all_iterators();
3148    if (__is_long())
3149    {
3150        traits_type::assign(*__get_long_pointer(), value_type());
3151        __set_long_size(0);
3152    }
3153    else
3154    {
3155        traits_type::assign(*__get_short_pointer(), value_type());
3156        __set_short_size(0);
3157    }
3158}
3159
3160template <class _CharT, class _Traits, class _Allocator>
3161inline _LIBCPP_INLINE_VISIBILITY
3162void
3163basic_string<_CharT, _Traits, _Allocator>::__erase_to_end(size_type __pos)
3164{
3165    if (__is_long())
3166    {
3167        traits_type::assign(*(__get_long_pointer() + __pos), value_type());
3168        __set_long_size(__pos);
3169    }
3170    else
3171    {
3172        traits_type::assign(*(__get_short_pointer() + __pos), value_type());
3173        __set_short_size(__pos);
3174    }
3175    __invalidate_iterators_past(__pos);
3176}
3177
3178template <class _CharT, class _Traits, class _Allocator>
3179void
3180basic_string<_CharT, _Traits, _Allocator>::resize(size_type __n, value_type __c)
3181{
3182    size_type __sz = size();
3183    if (__n > __sz)
3184        append(__n - __sz, __c);
3185    else
3186        __erase_to_end(__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>::max_size() const _NOEXCEPT
3193{
3194    size_type __m = __alloc_traits::max_size(__alloc());
3195#if _LIBCPP_BIG_ENDIAN
3196    return (__m <= ~__long_mask ? __m : __m/2) - __alignment;
3197#else
3198    return __m - __alignment;
3199#endif
3200}
3201
3202template <class _CharT, class _Traits, class _Allocator>
3203void
3204basic_string<_CharT, _Traits, _Allocator>::reserve(size_type __res_arg)
3205{
3206    if (__res_arg > max_size())
3207        this->__throw_length_error();
3208    size_type __cap = capacity();
3209    size_type __sz = size();
3210    __res_arg = _VSTD::max(__res_arg, __sz);
3211    __res_arg = __recommend(__res_arg);
3212    if (__res_arg != __cap)
3213    {
3214        pointer __new_data, __p;
3215        bool __was_long, __now_long;
3216        if (__res_arg == __min_cap - 1)
3217        {
3218            __was_long = true;
3219            __now_long = false;
3220            __new_data = __get_short_pointer();
3221            __p = __get_long_pointer();
3222        }
3223        else
3224        {
3225            if (__res_arg > __cap)
3226                __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
3227            else
3228            {
3229            #ifndef _LIBCPP_NO_EXCEPTIONS
3230                try
3231                {
3232            #endif  // _LIBCPP_NO_EXCEPTIONS
3233                    __new_data = __alloc_traits::allocate(__alloc(), __res_arg+1);
3234            #ifndef _LIBCPP_NO_EXCEPTIONS
3235                }
3236                catch (...)
3237                {
3238                    return;
3239                }
3240            #else  // _LIBCPP_NO_EXCEPTIONS
3241                if (__new_data == nullptr)
3242                    return;
3243            #endif  // _LIBCPP_NO_EXCEPTIONS
3244            }
3245            __now_long = true;
3246            __was_long = __is_long();
3247            __p = __get_pointer();
3248        }
3249        traits_type::copy(_VSTD::__to_raw_pointer(__new_data),
3250                          _VSTD::__to_raw_pointer(__p), size()+1);
3251        if (__was_long)
3252            __alloc_traits::deallocate(__alloc(), __p, __cap+1);
3253        if (__now_long)
3254        {
3255            __set_long_cap(__res_arg+1);
3256            __set_long_size(__sz);
3257            __set_long_pointer(__new_data);
3258        }
3259        else
3260            __set_short_size(__sz);
3261        __invalidate_all_iterators();
3262    }
3263}
3264
3265template <class _CharT, class _Traits, class _Allocator>
3266inline _LIBCPP_INLINE_VISIBILITY
3267typename basic_string<_CharT, _Traits, _Allocator>::const_reference
3268basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos) const
3269{
3270    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
3271    return *(data() + __pos);
3272}
3273
3274template <class _CharT, class _Traits, class _Allocator>
3275inline _LIBCPP_INLINE_VISIBILITY
3276typename basic_string<_CharT, _Traits, _Allocator>::reference
3277basic_string<_CharT, _Traits, _Allocator>::operator[](size_type __pos)
3278{
3279    _LIBCPP_ASSERT(__pos <= size(), "string index out of bounds");
3280    return *(__get_pointer() + __pos);
3281}
3282
3283template <class _CharT, class _Traits, class _Allocator>
3284typename basic_string<_CharT, _Traits, _Allocator>::const_reference
3285basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) const
3286{
3287    if (__n >= size())
3288        this->__throw_out_of_range();
3289    return (*this)[__n];
3290}
3291
3292template <class _CharT, class _Traits, class _Allocator>
3293typename basic_string<_CharT, _Traits, _Allocator>::reference
3294basic_string<_CharT, _Traits, _Allocator>::at(size_type __n)
3295{
3296    if (__n >= size())
3297        this->__throw_out_of_range();
3298    return (*this)[__n];
3299}
3300
3301template <class _CharT, class _Traits, class _Allocator>
3302inline _LIBCPP_INLINE_VISIBILITY
3303typename basic_string<_CharT, _Traits, _Allocator>::reference
3304basic_string<_CharT, _Traits, _Allocator>::front()
3305{
3306    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
3307    return *__get_pointer();
3308}
3309
3310template <class _CharT, class _Traits, class _Allocator>
3311inline _LIBCPP_INLINE_VISIBILITY
3312typename basic_string<_CharT, _Traits, _Allocator>::const_reference
3313basic_string<_CharT, _Traits, _Allocator>::front() const
3314{
3315    _LIBCPP_ASSERT(!empty(), "string::front(): string is empty");
3316    return *data();
3317}
3318
3319template <class _CharT, class _Traits, class _Allocator>
3320inline _LIBCPP_INLINE_VISIBILITY
3321typename basic_string<_CharT, _Traits, _Allocator>::reference
3322basic_string<_CharT, _Traits, _Allocator>::back()
3323{
3324    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
3325    return *(__get_pointer() + size() - 1);
3326}
3327
3328template <class _CharT, class _Traits, class _Allocator>
3329inline _LIBCPP_INLINE_VISIBILITY
3330typename basic_string<_CharT, _Traits, _Allocator>::const_reference
3331basic_string<_CharT, _Traits, _Allocator>::back() const
3332{
3333    _LIBCPP_ASSERT(!empty(), "string::back(): string is empty");
3334    return *(data() + size() - 1);
3335}
3336
3337template <class _CharT, class _Traits, class _Allocator>
3338typename basic_string<_CharT, _Traits, _Allocator>::size_type
3339basic_string<_CharT, _Traits, _Allocator>::copy(value_type* __s, size_type __n, size_type __pos) const
3340{
3341    size_type __sz = size();
3342    if (__pos > __sz)
3343        this->__throw_out_of_range();
3344    size_type __rlen = _VSTD::min(__n, __sz - __pos);
3345    traits_type::copy(__s, data() + __pos, __rlen);
3346    return __rlen;
3347}
3348
3349template <class _CharT, class _Traits, class _Allocator>
3350inline _LIBCPP_INLINE_VISIBILITY
3351basic_string<_CharT, _Traits, _Allocator>
3352basic_string<_CharT, _Traits, _Allocator>::substr(size_type __pos, size_type __n) const
3353{
3354    return basic_string(*this, __pos, __n, __alloc());
3355}
3356
3357template <class _CharT, class _Traits, class _Allocator>
3358inline _LIBCPP_INLINE_VISIBILITY
3359void
3360basic_string<_CharT, _Traits, _Allocator>::swap(basic_string& __str)
3361#if _LIBCPP_STD_VER >= 14
3362        _NOEXCEPT
3363#else
3364        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
3365                    __is_nothrow_swappable<allocator_type>::value)
3366#endif
3367{
3368#if _LIBCPP_DEBUG_LEVEL >= 2
3369    if (!__is_long())
3370        __get_db()->__invalidate_all(this);
3371    if (!__str.__is_long())
3372        __get_db()->__invalidate_all(&__str);
3373    __get_db()->swap(this, &__str);
3374#endif
3375    _VSTD::swap(__r_.first(), __str.__r_.first());
3376    __swap_allocator(__alloc(), __str.__alloc());
3377}
3378
3379// find
3380
3381template <class _Traits>
3382struct _LIBCPP_HIDDEN __traits_eq
3383{
3384    typedef typename _Traits::char_type char_type;
3385    _LIBCPP_INLINE_VISIBILITY
3386    bool operator()(const char_type& __x, const char_type& __y) _NOEXCEPT
3387        {return _Traits::eq(__x, __y);}
3388};
3389
3390template<class _CharT, class _Traits, class _Allocator>
3391typename basic_string<_CharT, _Traits, _Allocator>::size_type
3392basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3393                                                size_type __pos,
3394                                                size_type __n) const _NOEXCEPT
3395{
3396    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find(): received nullptr");
3397    return _VSTD::__str_find<value_type, size_type, traits_type, npos>
3398        (data(), size(), __s, __pos, __n);
3399}
3400
3401template<class _CharT, class _Traits, class _Allocator>
3402inline _LIBCPP_INLINE_VISIBILITY
3403typename basic_string<_CharT, _Traits, _Allocator>::size_type
3404basic_string<_CharT, _Traits, _Allocator>::find(const basic_string& __str,
3405                                                size_type __pos) const _NOEXCEPT
3406{
3407    return _VSTD::__str_find<value_type, size_type, traits_type, npos>
3408        (data(), size(), __str.data(), __pos, __str.size());
3409}
3410
3411template<class _CharT, class _Traits, class _Allocator>
3412inline _LIBCPP_INLINE_VISIBILITY
3413typename basic_string<_CharT, _Traits, _Allocator>::size_type
3414basic_string<_CharT, _Traits, _Allocator>::find(const value_type* __s,
3415                                                size_type __pos) const _NOEXCEPT
3416{
3417    _LIBCPP_ASSERT(__s != nullptr, "string::find(): received nullptr");
3418    return _VSTD::__str_find<value_type, size_type, traits_type, npos>
3419        (data(), size(), __s, __pos, traits_type::length(__s));
3420}
3421
3422template<class _CharT, class _Traits, class _Allocator>
3423typename basic_string<_CharT, _Traits, _Allocator>::size_type
3424basic_string<_CharT, _Traits, _Allocator>::find(value_type __c,
3425                                                size_type __pos) const _NOEXCEPT
3426{
3427    return _VSTD::__str_find<value_type, size_type, traits_type, npos>
3428        (data(), size(), __c, __pos);
3429}
3430
3431// rfind
3432
3433template<class _CharT, class _Traits, class _Allocator>
3434typename basic_string<_CharT, _Traits, _Allocator>::size_type
3435basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3436                                                 size_type __pos,
3437                                                 size_type __n) const _NOEXCEPT
3438{
3439    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::rfind(): received nullptr");
3440    return _VSTD::__str_rfind<value_type, size_type, traits_type, npos>
3441        (data(), size(), __s, __pos, __n);
3442}
3443
3444template<class _CharT, class _Traits, class _Allocator>
3445inline _LIBCPP_INLINE_VISIBILITY
3446typename basic_string<_CharT, _Traits, _Allocator>::size_type
3447basic_string<_CharT, _Traits, _Allocator>::rfind(const basic_string& __str,
3448                                                 size_type __pos) const _NOEXCEPT
3449{
3450    return _VSTD::__str_rfind<value_type, size_type, traits_type, npos>
3451        (data(), size(), __str.data(), __pos, __str.size());
3452}
3453
3454template<class _CharT, class _Traits, class _Allocator>
3455inline _LIBCPP_INLINE_VISIBILITY
3456typename basic_string<_CharT, _Traits, _Allocator>::size_type
3457basic_string<_CharT, _Traits, _Allocator>::rfind(const value_type* __s,
3458                                                 size_type __pos) const _NOEXCEPT
3459{
3460    _LIBCPP_ASSERT(__s != nullptr, "string::rfind(): received nullptr");
3461    return _VSTD::__str_rfind<value_type, size_type, traits_type, npos>
3462        (data(), size(), __s, __pos, traits_type::length(__s));
3463}
3464
3465template<class _CharT, class _Traits, class _Allocator>
3466typename basic_string<_CharT, _Traits, _Allocator>::size_type
3467basic_string<_CharT, _Traits, _Allocator>::rfind(value_type __c,
3468                                                 size_type __pos) const _NOEXCEPT
3469{
3470    return _VSTD::__str_rfind<value_type, size_type, traits_type, npos>
3471        (data(), size(), __c, __pos);
3472}
3473
3474// find_first_of
3475
3476template<class _CharT, class _Traits, class _Allocator>
3477typename basic_string<_CharT, _Traits, _Allocator>::size_type
3478basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3479                                                         size_type __pos,
3480                                                         size_type __n) const _NOEXCEPT
3481{
3482    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_of(): received nullptr");
3483    return _VSTD::__str_find_first_of<value_type, size_type, traits_type, npos>
3484        (data(), size(), __s, __pos, __n);
3485}
3486
3487template<class _CharT, class _Traits, class _Allocator>
3488inline _LIBCPP_INLINE_VISIBILITY
3489typename basic_string<_CharT, _Traits, _Allocator>::size_type
3490basic_string<_CharT, _Traits, _Allocator>::find_first_of(const basic_string& __str,
3491                                                         size_type __pos) const _NOEXCEPT
3492{
3493    return _VSTD::__str_find_first_of<value_type, size_type, traits_type, npos>
3494        (data(), size(), __str.data(), __pos, __str.size());
3495}
3496
3497template<class _CharT, class _Traits, class _Allocator>
3498inline _LIBCPP_INLINE_VISIBILITY
3499typename basic_string<_CharT, _Traits, _Allocator>::size_type
3500basic_string<_CharT, _Traits, _Allocator>::find_first_of(const value_type* __s,
3501                                                         size_type __pos) const _NOEXCEPT
3502{
3503    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_of(): received nullptr");
3504    return _VSTD::__str_find_first_of<value_type, size_type, traits_type, npos>
3505        (data(), size(), __s, __pos, traits_type::length(__s));
3506}
3507
3508template<class _CharT, class _Traits, class _Allocator>
3509inline _LIBCPP_INLINE_VISIBILITY
3510typename basic_string<_CharT, _Traits, _Allocator>::size_type
3511basic_string<_CharT, _Traits, _Allocator>::find_first_of(value_type __c,
3512                                                         size_type __pos) const _NOEXCEPT
3513{
3514    return find(__c, __pos);
3515}
3516
3517// find_last_of
3518
3519template<class _CharT, class _Traits, class _Allocator>
3520typename basic_string<_CharT, _Traits, _Allocator>::size_type
3521basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3522                                                        size_type __pos,
3523                                                        size_type __n) const _NOEXCEPT
3524{
3525    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_of(): received nullptr");
3526    return _VSTD::__str_find_last_of<value_type, size_type, traits_type, npos>
3527        (data(), size(), __s, __pos, __n);
3528}
3529
3530template<class _CharT, class _Traits, class _Allocator>
3531inline _LIBCPP_INLINE_VISIBILITY
3532typename basic_string<_CharT, _Traits, _Allocator>::size_type
3533basic_string<_CharT, _Traits, _Allocator>::find_last_of(const basic_string& __str,
3534                                                        size_type __pos) const _NOEXCEPT
3535{
3536    return _VSTD::__str_find_last_of<value_type, size_type, traits_type, npos>
3537        (data(), size(), __str.data(), __pos, __str.size());
3538}
3539
3540template<class _CharT, class _Traits, class _Allocator>
3541inline _LIBCPP_INLINE_VISIBILITY
3542typename basic_string<_CharT, _Traits, _Allocator>::size_type
3543basic_string<_CharT, _Traits, _Allocator>::find_last_of(const value_type* __s,
3544                                                        size_type __pos) const _NOEXCEPT
3545{
3546    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_of(): received nullptr");
3547    return _VSTD::__str_find_last_of<value_type, size_type, traits_type, npos>
3548        (data(), size(), __s, __pos, traits_type::length(__s));
3549}
3550
3551template<class _CharT, class _Traits, class _Allocator>
3552inline _LIBCPP_INLINE_VISIBILITY
3553typename basic_string<_CharT, _Traits, _Allocator>::size_type
3554basic_string<_CharT, _Traits, _Allocator>::find_last_of(value_type __c,
3555                                                        size_type __pos) const _NOEXCEPT
3556{
3557    return rfind(__c, __pos);
3558}
3559
3560// find_first_not_of
3561
3562template<class _CharT, class _Traits, class _Allocator>
3563typename basic_string<_CharT, _Traits, _Allocator>::size_type
3564basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3565                                                             size_type __pos,
3566                                                             size_type __n) const _NOEXCEPT
3567{
3568    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_first_not_of(): received nullptr");
3569    return _VSTD::__str_find_first_not_of<value_type, size_type, traits_type, npos>
3570        (data(), size(), __s, __pos, __n);
3571}
3572
3573template<class _CharT, class _Traits, class _Allocator>
3574inline _LIBCPP_INLINE_VISIBILITY
3575typename basic_string<_CharT, _Traits, _Allocator>::size_type
3576basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const basic_string& __str,
3577                                                             size_type __pos) const _NOEXCEPT
3578{
3579    return _VSTD::__str_find_first_not_of<value_type, size_type, traits_type, npos>
3580        (data(), size(), __str.data(), __pos, __str.size());
3581}
3582
3583template<class _CharT, class _Traits, class _Allocator>
3584inline _LIBCPP_INLINE_VISIBILITY
3585typename basic_string<_CharT, _Traits, _Allocator>::size_type
3586basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(const value_type* __s,
3587                                                             size_type __pos) const _NOEXCEPT
3588{
3589    _LIBCPP_ASSERT(__s != nullptr, "string::find_first_not_of(): received nullptr");
3590    return _VSTD::__str_find_first_not_of<value_type, size_type, traits_type, npos>
3591        (data(), size(), __s, __pos, traits_type::length(__s));
3592}
3593
3594template<class _CharT, class _Traits, class _Allocator>
3595inline _LIBCPP_INLINE_VISIBILITY
3596typename basic_string<_CharT, _Traits, _Allocator>::size_type
3597basic_string<_CharT, _Traits, _Allocator>::find_first_not_of(value_type __c,
3598                                                             size_type __pos) const _NOEXCEPT
3599{
3600    return _VSTD::__str_find_first_not_of<value_type, size_type, traits_type, npos>
3601        (data(), size(), __c, __pos);
3602}
3603
3604// find_last_not_of
3605
3606template<class _CharT, class _Traits, class _Allocator>
3607typename basic_string<_CharT, _Traits, _Allocator>::size_type
3608basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3609                                                            size_type __pos,
3610                                                            size_type __n) const _NOEXCEPT
3611{
3612    _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::find_last_not_of(): received nullptr");
3613    return _VSTD::__str_find_last_not_of<value_type, size_type, traits_type, npos>
3614        (data(), size(), __s, __pos, __n);
3615}
3616
3617template<class _CharT, class _Traits, class _Allocator>
3618inline _LIBCPP_INLINE_VISIBILITY
3619typename basic_string<_CharT, _Traits, _Allocator>::size_type
3620basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const basic_string& __str,
3621                                                            size_type __pos) const _NOEXCEPT
3622{
3623    return _VSTD::__str_find_last_not_of<value_type, size_type, traits_type, npos>
3624        (data(), size(), __str.data(), __pos, __str.size());
3625}
3626
3627template<class _CharT, class _Traits, class _Allocator>
3628inline _LIBCPP_INLINE_VISIBILITY
3629typename basic_string<_CharT, _Traits, _Allocator>::size_type
3630basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(const value_type* __s,
3631                                                            size_type __pos) const _NOEXCEPT
3632{
3633    _LIBCPP_ASSERT(__s != nullptr, "string::find_last_not_of(): received nullptr");
3634    return _VSTD::__str_find_last_not_of<value_type, size_type, traits_type, npos>
3635        (data(), size(), __s, __pos, traits_type::length(__s));
3636}
3637
3638template<class _CharT, class _Traits, class _Allocator>
3639inline _LIBCPP_INLINE_VISIBILITY
3640typename basic_string<_CharT, _Traits, _Allocator>::size_type
3641basic_string<_CharT, _Traits, _Allocator>::find_last_not_of(value_type __c,
3642                                                            size_type __pos) const _NOEXCEPT
3643{
3644    return _VSTD::__str_find_last_not_of<value_type, size_type, traits_type, npos>
3645        (data(), size(), __c, __pos);
3646}
3647
3648// compare
3649
3650template <class _CharT, class _Traits, class _Allocator>
3651inline _LIBCPP_INLINE_VISIBILITY
3652int
3653basic_string<_CharT, _Traits, _Allocator>::compare(const basic_string& __str) const _NOEXCEPT
3654{
3655    size_t __lhs_sz = size();
3656    size_t __rhs_sz = __str.size();
3657    int __result = traits_type::compare(data(), __str.data(),
3658                                        _VSTD::min(__lhs_sz, __rhs_sz));
3659    if (__result != 0)
3660        return __result;
3661    if (__lhs_sz < __rhs_sz)
3662        return -1;
3663    if (__lhs_sz > __rhs_sz)
3664        return 1;
3665    return 0;
3666}
3667
3668template <class _CharT, class _Traits, class _Allocator>
3669inline _LIBCPP_INLINE_VISIBILITY
3670int
3671basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3672                                                   size_type __n1,
3673                                                   const basic_string& __str) const
3674{
3675    return compare(__pos1, __n1, __str.data(), __str.size());
3676}
3677
3678template <class _CharT, class _Traits, class _Allocator>
3679int
3680basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3681                                                   size_type __n1,
3682                                                   const basic_string& __str,
3683                                                   size_type __pos2,
3684                                                   size_type __n2) const
3685{
3686    size_type __sz = __str.size();
3687    if (__pos2 > __sz)
3688        this->__throw_out_of_range();
3689    return compare(__pos1, __n1, __str.data() + __pos2, _VSTD::min(__n2,
3690                                                                  __sz - __pos2));
3691}
3692
3693template <class _CharT, class _Traits, class _Allocator>
3694int
3695basic_string<_CharT, _Traits, _Allocator>::compare(const value_type* __s) const _NOEXCEPT
3696{
3697    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3698    return compare(0, npos, __s, traits_type::length(__s));
3699}
3700
3701template <class _CharT, class _Traits, class _Allocator>
3702int
3703basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3704                                                   size_type __n1,
3705                                                   const value_type* __s) const
3706{
3707    _LIBCPP_ASSERT(__s != nullptr, "string::compare(): received nullptr");
3708    return compare(__pos1, __n1, __s, traits_type::length(__s));
3709}
3710
3711template <class _CharT, class _Traits, class _Allocator>
3712int
3713basic_string<_CharT, _Traits, _Allocator>::compare(size_type __pos1,
3714                                                   size_type __n1,
3715                                                   const value_type* __s,
3716                                                   size_type __n2) const
3717{
3718    _LIBCPP_ASSERT(__n2 == 0 || __s != nullptr, "string::compare(): received nullptr");
3719    size_type __sz = size();
3720    if (__pos1 > __sz || __n2 == npos)
3721        this->__throw_out_of_range();
3722    size_type __rlen = _VSTD::min(__n1, __sz - __pos1);
3723    int __r = traits_type::compare(data() + __pos1, __s, _VSTD::min(__rlen, __n2));
3724    if (__r == 0)
3725    {
3726        if (__rlen < __n2)
3727            __r = -1;
3728        else if (__rlen > __n2)
3729            __r = 1;
3730    }
3731    return __r;
3732}
3733
3734// __invariants
3735
3736template<class _CharT, class _Traits, class _Allocator>
3737inline _LIBCPP_INLINE_VISIBILITY
3738bool
3739basic_string<_CharT, _Traits, _Allocator>::__invariants() const
3740{
3741    if (size() > capacity())
3742        return false;
3743    if (capacity() < __min_cap - 1)
3744        return false;
3745    if (data() == 0)
3746        return false;
3747    if (data()[size()] != value_type(0))
3748        return false;
3749    return true;
3750}
3751
3752// operator==
3753
3754template<class _CharT, class _Traits, class _Allocator>
3755inline _LIBCPP_INLINE_VISIBILITY
3756bool
3757operator==(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3758           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3759{
3760    size_t __lhs_sz = __lhs.size();
3761    return __lhs_sz == __rhs.size() && _Traits::compare(__lhs.data(),
3762                                                        __rhs.data(),
3763                                                        __lhs_sz) == 0;
3764}
3765
3766template<class _Allocator>
3767inline _LIBCPP_INLINE_VISIBILITY
3768bool
3769operator==(const basic_string<char, char_traits<char>, _Allocator>& __lhs,
3770           const basic_string<char, char_traits<char>, _Allocator>& __rhs) _NOEXCEPT
3771{
3772    size_t __lhs_sz = __lhs.size();
3773    if (__lhs_sz != __rhs.size())
3774        return false;
3775    const char* __lp = __lhs.data();
3776    const char* __rp = __rhs.data();
3777    if (__lhs.__is_long())
3778        return char_traits<char>::compare(__lp, __rp, __lhs_sz) == 0;
3779    for (; __lhs_sz != 0; --__lhs_sz, ++__lp, ++__rp)
3780        if (*__lp != *__rp)
3781            return false;
3782    return true;
3783}
3784
3785template<class _CharT, class _Traits, class _Allocator>
3786inline _LIBCPP_INLINE_VISIBILITY
3787bool
3788operator==(const _CharT* __lhs,
3789           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3790{
3791    return __rhs.compare(__lhs) == 0;
3792}
3793
3794template<class _CharT, class _Traits, class _Allocator>
3795inline _LIBCPP_INLINE_VISIBILITY
3796bool
3797operator==(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3798           const _CharT* __rhs) _NOEXCEPT
3799{
3800    return __lhs.compare(__rhs) == 0;
3801}
3802
3803// operator!=
3804
3805template<class _CharT, class _Traits, class _Allocator>
3806inline _LIBCPP_INLINE_VISIBILITY
3807bool
3808operator!=(const basic_string<_CharT,_Traits,_Allocator>& __lhs,
3809           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3810{
3811    return !(__lhs == __rhs);
3812}
3813
3814template<class _CharT, class _Traits, class _Allocator>
3815inline _LIBCPP_INLINE_VISIBILITY
3816bool
3817operator!=(const _CharT* __lhs,
3818           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3819{
3820    return !(__lhs == __rhs);
3821}
3822
3823template<class _CharT, class _Traits, class _Allocator>
3824inline _LIBCPP_INLINE_VISIBILITY
3825bool
3826operator!=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3827           const _CharT* __rhs) _NOEXCEPT
3828{
3829    return !(__lhs == __rhs);
3830}
3831
3832// operator<
3833
3834template<class _CharT, class _Traits, class _Allocator>
3835inline _LIBCPP_INLINE_VISIBILITY
3836bool
3837operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3838           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3839{
3840    return __lhs.compare(__rhs) < 0;
3841}
3842
3843template<class _CharT, class _Traits, class _Allocator>
3844inline _LIBCPP_INLINE_VISIBILITY
3845bool
3846operator< (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3847           const _CharT* __rhs) _NOEXCEPT
3848{
3849    return __lhs.compare(__rhs) < 0;
3850}
3851
3852template<class _CharT, class _Traits, class _Allocator>
3853inline _LIBCPP_INLINE_VISIBILITY
3854bool
3855operator< (const _CharT* __lhs,
3856           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3857{
3858    return __rhs.compare(__lhs) > 0;
3859}
3860
3861// operator>
3862
3863template<class _CharT, class _Traits, class _Allocator>
3864inline _LIBCPP_INLINE_VISIBILITY
3865bool
3866operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3867           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3868{
3869    return __rhs < __lhs;
3870}
3871
3872template<class _CharT, class _Traits, class _Allocator>
3873inline _LIBCPP_INLINE_VISIBILITY
3874bool
3875operator> (const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3876           const _CharT* __rhs) _NOEXCEPT
3877{
3878    return __rhs < __lhs;
3879}
3880
3881template<class _CharT, class _Traits, class _Allocator>
3882inline _LIBCPP_INLINE_VISIBILITY
3883bool
3884operator> (const _CharT* __lhs,
3885           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3886{
3887    return __rhs < __lhs;
3888}
3889
3890// operator<=
3891
3892template<class _CharT, class _Traits, class _Allocator>
3893inline _LIBCPP_INLINE_VISIBILITY
3894bool
3895operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3896           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3897{
3898    return !(__rhs < __lhs);
3899}
3900
3901template<class _CharT, class _Traits, class _Allocator>
3902inline _LIBCPP_INLINE_VISIBILITY
3903bool
3904operator<=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3905           const _CharT* __rhs) _NOEXCEPT
3906{
3907    return !(__rhs < __lhs);
3908}
3909
3910template<class _CharT, class _Traits, class _Allocator>
3911inline _LIBCPP_INLINE_VISIBILITY
3912bool
3913operator<=(const _CharT* __lhs,
3914           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3915{
3916    return !(__rhs < __lhs);
3917}
3918
3919// operator>=
3920
3921template<class _CharT, class _Traits, class _Allocator>
3922inline _LIBCPP_INLINE_VISIBILITY
3923bool
3924operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3925           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3926{
3927    return !(__lhs < __rhs);
3928}
3929
3930template<class _CharT, class _Traits, class _Allocator>
3931inline _LIBCPP_INLINE_VISIBILITY
3932bool
3933operator>=(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3934           const _CharT* __rhs) _NOEXCEPT
3935{
3936    return !(__lhs < __rhs);
3937}
3938
3939template<class _CharT, class _Traits, class _Allocator>
3940inline _LIBCPP_INLINE_VISIBILITY
3941bool
3942operator>=(const _CharT* __lhs,
3943           const basic_string<_CharT, _Traits, _Allocator>& __rhs) _NOEXCEPT
3944{
3945    return !(__lhs < __rhs);
3946}
3947
3948// operator +
3949
3950template<class _CharT, class _Traits, class _Allocator>
3951basic_string<_CharT, _Traits, _Allocator>
3952operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs,
3953          const basic_string<_CharT, _Traits, _Allocator>& __rhs)
3954{
3955    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3956    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3957    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3958    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3959    __r.append(__rhs.data(), __rhs_sz);
3960    return __r;
3961}
3962
3963template<class _CharT, class _Traits, class _Allocator>
3964basic_string<_CharT, _Traits, _Allocator>
3965operator+(const _CharT* __lhs , const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3966{
3967    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3968    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = _Traits::length(__lhs);
3969    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3970    __r.__init(__lhs, __lhs_sz, __lhs_sz + __rhs_sz);
3971    __r.append(__rhs.data(), __rhs_sz);
3972    return __r;
3973}
3974
3975template<class _CharT, class _Traits, class _Allocator>
3976basic_string<_CharT, _Traits, _Allocator>
3977operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Allocator>& __rhs)
3978{
3979    basic_string<_CharT, _Traits, _Allocator> __r(__rhs.get_allocator());
3980    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = __rhs.size();
3981    __r.__init(&__lhs, 1, 1 + __rhs_sz);
3982    __r.append(__rhs.data(), __rhs_sz);
3983    return __r;
3984}
3985
3986template<class _CharT, class _Traits, class _Allocator>
3987basic_string<_CharT, _Traits, _Allocator>
3988operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, const _CharT* __rhs)
3989{
3990    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
3991    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
3992    typename basic_string<_CharT, _Traits, _Allocator>::size_type __rhs_sz = _Traits::length(__rhs);
3993    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + __rhs_sz);
3994    __r.append(__rhs, __rhs_sz);
3995    return __r;
3996}
3997
3998template<class _CharT, class _Traits, class _Allocator>
3999basic_string<_CharT, _Traits, _Allocator>
4000operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, _CharT __rhs)
4001{
4002    basic_string<_CharT, _Traits, _Allocator> __r(__lhs.get_allocator());
4003    typename basic_string<_CharT, _Traits, _Allocator>::size_type __lhs_sz = __lhs.size();
4004    __r.__init(__lhs.data(), __lhs_sz, __lhs_sz + 1);
4005    __r.push_back(__rhs);
4006    return __r;
4007}
4008
4009#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4010
4011template<class _CharT, class _Traits, class _Allocator>
4012inline _LIBCPP_INLINE_VISIBILITY
4013basic_string<_CharT, _Traits, _Allocator>
4014operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const basic_string<_CharT, _Traits, _Allocator>& __rhs)
4015{
4016    return _VSTD::move(__lhs.append(__rhs));
4017}
4018
4019template<class _CharT, class _Traits, class _Allocator>
4020inline _LIBCPP_INLINE_VISIBILITY
4021basic_string<_CharT, _Traits, _Allocator>
4022operator+(const basic_string<_CharT, _Traits, _Allocator>& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
4023{
4024    return _VSTD::move(__rhs.insert(0, __lhs));
4025}
4026
4027template<class _CharT, class _Traits, class _Allocator>
4028inline _LIBCPP_INLINE_VISIBILITY
4029basic_string<_CharT, _Traits, _Allocator>
4030operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, basic_string<_CharT, _Traits, _Allocator>&& __rhs)
4031{
4032    return _VSTD::move(__lhs.append(__rhs));
4033}
4034
4035template<class _CharT, class _Traits, class _Allocator>
4036inline _LIBCPP_INLINE_VISIBILITY
4037basic_string<_CharT, _Traits, _Allocator>
4038operator+(const _CharT* __lhs , basic_string<_CharT,_Traits,_Allocator>&& __rhs)
4039{
4040    return _VSTD::move(__rhs.insert(0, __lhs));
4041}
4042
4043template<class _CharT, class _Traits, class _Allocator>
4044inline _LIBCPP_INLINE_VISIBILITY
4045basic_string<_CharT, _Traits, _Allocator>
4046operator+(_CharT __lhs, basic_string<_CharT,_Traits,_Allocator>&& __rhs)
4047{
4048    __rhs.insert(__rhs.begin(), __lhs);
4049    return _VSTD::move(__rhs);
4050}
4051
4052template<class _CharT, class _Traits, class _Allocator>
4053inline _LIBCPP_INLINE_VISIBILITY
4054basic_string<_CharT, _Traits, _Allocator>
4055operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, const _CharT* __rhs)
4056{
4057    return _VSTD::move(__lhs.append(__rhs));
4058}
4059
4060template<class _CharT, class _Traits, class _Allocator>
4061inline _LIBCPP_INLINE_VISIBILITY
4062basic_string<_CharT, _Traits, _Allocator>
4063operator+(basic_string<_CharT, _Traits, _Allocator>&& __lhs, _CharT __rhs)
4064{
4065    __lhs.push_back(__rhs);
4066    return _VSTD::move(__lhs);
4067}
4068
4069#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4070
4071// swap
4072
4073template<class _CharT, class _Traits, class _Allocator>
4074inline _LIBCPP_INLINE_VISIBILITY
4075void
4076swap(basic_string<_CharT, _Traits, _Allocator>& __lhs,
4077     basic_string<_CharT, _Traits, _Allocator>& __rhs)
4078     _NOEXCEPT_(_NOEXCEPT_(__lhs.swap(__rhs)))
4079{
4080    __lhs.swap(__rhs);
4081}
4082
4083#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
4084
4085typedef basic_string<char16_t> u16string;
4086typedef basic_string<char32_t> u32string;
4087
4088#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
4089
4090_LIBCPP_FUNC_VIS int                stoi  (const string& __str, size_t* __idx = 0, int __base = 10);
4091_LIBCPP_FUNC_VIS long               stol  (const string& __str, size_t* __idx = 0, int __base = 10);
4092_LIBCPP_FUNC_VIS unsigned long      stoul (const string& __str, size_t* __idx = 0, int __base = 10);
4093_LIBCPP_FUNC_VIS long long          stoll (const string& __str, size_t* __idx = 0, int __base = 10);
4094_LIBCPP_FUNC_VIS unsigned long long stoull(const string& __str, size_t* __idx = 0, int __base = 10);
4095
4096_LIBCPP_FUNC_VIS float       stof (const string& __str, size_t* __idx = 0);
4097_LIBCPP_FUNC_VIS double      stod (const string& __str, size_t* __idx = 0);
4098_LIBCPP_FUNC_VIS long double stold(const string& __str, size_t* __idx = 0);
4099
4100_LIBCPP_FUNC_VIS string to_string(int __val);
4101_LIBCPP_FUNC_VIS string to_string(unsigned __val);
4102_LIBCPP_FUNC_VIS string to_string(long __val);
4103_LIBCPP_FUNC_VIS string to_string(unsigned long __val);
4104_LIBCPP_FUNC_VIS string to_string(long long __val);
4105_LIBCPP_FUNC_VIS string to_string(unsigned long long __val);
4106_LIBCPP_FUNC_VIS string to_string(float __val);
4107_LIBCPP_FUNC_VIS string to_string(double __val);
4108_LIBCPP_FUNC_VIS string to_string(long double __val);
4109
4110_LIBCPP_FUNC_VIS int                stoi  (const wstring& __str, size_t* __idx = 0, int __base = 10);
4111_LIBCPP_FUNC_VIS long               stol  (const wstring& __str, size_t* __idx = 0, int __base = 10);
4112_LIBCPP_FUNC_VIS unsigned long      stoul (const wstring& __str, size_t* __idx = 0, int __base = 10);
4113_LIBCPP_FUNC_VIS long long          stoll (const wstring& __str, size_t* __idx = 0, int __base = 10);
4114_LIBCPP_FUNC_VIS unsigned long long stoull(const wstring& __str, size_t* __idx = 0, int __base = 10);
4115
4116_LIBCPP_FUNC_VIS float       stof (const wstring& __str, size_t* __idx = 0);
4117_LIBCPP_FUNC_VIS double      stod (const wstring& __str, size_t* __idx = 0);
4118_LIBCPP_FUNC_VIS long double stold(const wstring& __str, size_t* __idx = 0);
4119
4120_LIBCPP_FUNC_VIS wstring to_wstring(int __val);
4121_LIBCPP_FUNC_VIS wstring to_wstring(unsigned __val);
4122_LIBCPP_FUNC_VIS wstring to_wstring(long __val);
4123_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long __val);
4124_LIBCPP_FUNC_VIS wstring to_wstring(long long __val);
4125_LIBCPP_FUNC_VIS wstring to_wstring(unsigned long long __val);
4126_LIBCPP_FUNC_VIS wstring to_wstring(float __val);
4127_LIBCPP_FUNC_VIS wstring to_wstring(double __val);
4128_LIBCPP_FUNC_VIS wstring to_wstring(long double __val);
4129
4130template<class _CharT, class _Traits, class _Allocator>
4131    const typename basic_string<_CharT, _Traits, _Allocator>::size_type
4132                   basic_string<_CharT, _Traits, _Allocator>::npos;
4133
4134template<class _CharT, class _Traits, class _Allocator>
4135struct _LIBCPP_TYPE_VIS_ONLY hash<basic_string<_CharT, _Traits, _Allocator> >
4136    : public unary_function<basic_string<_CharT, _Traits, _Allocator>, size_t>
4137{
4138    size_t
4139        operator()(const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT;
4140};
4141
4142template<class _CharT, class _Traits, class _Allocator>
4143size_t
4144hash<basic_string<_CharT, _Traits, _Allocator> >::operator()(
4145        const basic_string<_CharT, _Traits, _Allocator>& __val) const _NOEXCEPT
4146{
4147    return __do_string_hash(__val.data(), __val.data() + __val.size());
4148}
4149
4150template<class _CharT, class _Traits, class _Allocator>
4151basic_ostream<_CharT, _Traits>&
4152operator<<(basic_ostream<_CharT, _Traits>& __os,
4153           const basic_string<_CharT, _Traits, _Allocator>& __str);
4154
4155template<class _CharT, class _Traits, class _Allocator>
4156basic_istream<_CharT, _Traits>&
4157operator>>(basic_istream<_CharT, _Traits>& __is,
4158           basic_string<_CharT, _Traits, _Allocator>& __str);
4159
4160template<class _CharT, class _Traits, class _Allocator>
4161basic_istream<_CharT, _Traits>&
4162getline(basic_istream<_CharT, _Traits>& __is,
4163        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
4164
4165template<class _CharT, class _Traits, class _Allocator>
4166inline _LIBCPP_INLINE_VISIBILITY
4167basic_istream<_CharT, _Traits>&
4168getline(basic_istream<_CharT, _Traits>& __is,
4169        basic_string<_CharT, _Traits, _Allocator>& __str);
4170
4171#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4172
4173template<class _CharT, class _Traits, class _Allocator>
4174inline _LIBCPP_INLINE_VISIBILITY
4175basic_istream<_CharT, _Traits>&
4176getline(basic_istream<_CharT, _Traits>&& __is,
4177        basic_string<_CharT, _Traits, _Allocator>& __str, _CharT __dlm);
4178
4179template<class _CharT, class _Traits, class _Allocator>
4180inline _LIBCPP_INLINE_VISIBILITY
4181basic_istream<_CharT, _Traits>&
4182getline(basic_istream<_CharT, _Traits>&& __is,
4183        basic_string<_CharT, _Traits, _Allocator>& __str);
4184
4185#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4186
4187#if _LIBCPP_DEBUG_LEVEL >= 2
4188
4189template<class _CharT, class _Traits, class _Allocator>
4190bool
4191basic_string<_CharT, _Traits, _Allocator>::__dereferenceable(const const_iterator* __i) const
4192{
4193    return this->data() <= _VSTD::__to_raw_pointer(__i->base()) &&
4194           _VSTD::__to_raw_pointer(__i->base()) < this->data() + this->size();
4195}
4196
4197template<class _CharT, class _Traits, class _Allocator>
4198bool
4199basic_string<_CharT, _Traits, _Allocator>::__decrementable(const const_iterator* __i) const
4200{
4201    return this->data() < _VSTD::__to_raw_pointer(__i->base()) &&
4202           _VSTD::__to_raw_pointer(__i->base()) <= this->data() + this->size();
4203}
4204
4205template<class _CharT, class _Traits, class _Allocator>
4206bool
4207basic_string<_CharT, _Traits, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
4208{
4209    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
4210    return this->data() <= __p && __p <= this->data() + this->size();
4211}
4212
4213template<class _CharT, class _Traits, class _Allocator>
4214bool
4215basic_string<_CharT, _Traits, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
4216{
4217    const value_type* __p = _VSTD::__to_raw_pointer(__i->base()) + __n;
4218    return this->data() <= __p && __p < this->data() + this->size();
4219}
4220
4221#endif  // _LIBCPP_DEBUG_LEVEL >= 2
4222
4223#if _LIBCPP_STD_VER > 11
4224// Literal suffixes for basic_string [basic.string.literals]
4225inline namespace literals
4226{
4227  inline namespace string_literals
4228  {
4229    inline _LIBCPP_INLINE_VISIBILITY
4230    basic_string<char> operator "" s( const char *__str, size_t __len )
4231    {
4232        return basic_string<char> (__str, __len);
4233    }
4234
4235    inline _LIBCPP_INLINE_VISIBILITY
4236    basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
4237    {
4238        return basic_string<wchar_t> (__str, __len);
4239    }
4240
4241    inline _LIBCPP_INLINE_VISIBILITY
4242    basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
4243    {
4244        return basic_string<char16_t> (__str, __len);
4245    }
4246
4247    inline _LIBCPP_INLINE_VISIBILITY
4248    basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
4249    {
4250        return basic_string<char32_t> (__str, __len);
4251    }
4252  }
4253}
4254#endif
4255
4256_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_TYPE_VIS basic_string<char>)
4257_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_TYPE_VIS basic_string<wchar_t>)
4258_LIBCPP_EXTERN_TEMPLATE(string operator+<char, char_traits<char>, allocator<char> >(char const*, string const&))
4259
4260_LIBCPP_END_NAMESPACE_STD
4261
4262#endif  // _LIBCPP_STRING
4263