libstdc++
basic_string.h
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1 // Components for manipulating sequences of characters -*- C++ -*-
2 
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4 // 2006, 2007, 2008, 2009, 2010, 2011
5 // Free Software Foundation, Inc.
6 //
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12 
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17 
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21 
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26 
27 /** @file bits/basic_string.h
28  * This is an internal header file, included by other library headers.
29  * Do not attempt to use it directly. @headername{string}
30  */
31 
32 //
33 // ISO C++ 14882: 21 Strings library
34 //
35 
36 #ifndef _BASIC_STRING_H
37 #define _BASIC_STRING_H 1
38 
39 #pragma GCC system_header
40 
41 #include <ext/atomicity.h>
42 #include <debug/debug.h>
43 #include <initializer_list>
44 
45 namespace std _GLIBCXX_VISIBILITY(default)
46 {
47 _GLIBCXX_BEGIN_NAMESPACE_VERSION
48 
49  /**
50  * @class basic_string basic_string.h <string>
51  * @brief Managing sequences of characters and character-like objects.
52  *
53  * @ingroup strings
54  * @ingroup sequences
55  *
56  * Meets the requirements of a <a href="tables.html#65">container</a>, a
57  * <a href="tables.html#66">reversible container</a>, and a
58  * <a href="tables.html#67">sequence</a>. Of the
59  * <a href="tables.html#68">optional sequence requirements</a>, only
60  * @c push_back, @c at, and @c %array access are supported.
61  *
62  * @doctodo
63  *
64  *
65  * Documentation? What's that?
66  * Nathan Myers <ncm@cantrip.org>.
67  *
68  * A string looks like this:
69  *
70  * @code
71  * [_Rep]
72  * _M_length
73  * [basic_string<char_type>] _M_capacity
74  * _M_dataplus _M_refcount
75  * _M_p ----------------> unnamed array of char_type
76  * @endcode
77  *
78  * Where the _M_p points to the first character in the string, and
79  * you cast it to a pointer-to-_Rep and subtract 1 to get a
80  * pointer to the header.
81  *
82  * This approach has the enormous advantage that a string object
83  * requires only one allocation. All the ugliness is confined
84  * within a single %pair of inline functions, which each compile to
85  * a single @a add instruction: _Rep::_M_data(), and
86  * string::_M_rep(); and the allocation function which gets a
87  * block of raw bytes and with room enough and constructs a _Rep
88  * object at the front.
89  *
90  * The reason you want _M_data pointing to the character %array and
91  * not the _Rep is so that the debugger can see the string
92  * contents. (Probably we should add a non-inline member to get
93  * the _Rep for the debugger to use, so users can check the actual
94  * string length.)
95  *
96  * Note that the _Rep object is a POD so that you can have a
97  * static <em>empty string</em> _Rep object already @a constructed before
98  * static constructors have run. The reference-count encoding is
99  * chosen so that a 0 indicates one reference, so you never try to
100  * destroy the empty-string _Rep object.
101  *
102  * All but the last paragraph is considered pretty conventional
103  * for a C++ string implementation.
104  */
105  // 21.3 Template class basic_string
106  template<typename _CharT, typename _Traits, typename _Alloc>
108  {
109  typedef typename _Alloc::template rebind<_CharT>::other _CharT_alloc_type;
110 
111  // Types:
112  public:
113  typedef _Traits traits_type;
114  typedef typename _Traits::char_type value_type;
115  typedef _Alloc allocator_type;
116  typedef typename _CharT_alloc_type::size_type size_type;
117  typedef typename _CharT_alloc_type::difference_type difference_type;
118  typedef typename _CharT_alloc_type::reference reference;
119  typedef typename _CharT_alloc_type::const_reference const_reference;
120  typedef typename _CharT_alloc_type::pointer pointer;
121  typedef typename _CharT_alloc_type::const_pointer const_pointer;
122  typedef __gnu_cxx::__normal_iterator<pointer, basic_string> iterator;
123  typedef __gnu_cxx::__normal_iterator<const_pointer, basic_string>
124  const_iterator;
127 
128  private:
129  // _Rep: string representation
130  // Invariants:
131  // 1. String really contains _M_length + 1 characters: due to 21.3.4
132  // must be kept null-terminated.
133  // 2. _M_capacity >= _M_length
134  // Allocated memory is always (_M_capacity + 1) * sizeof(_CharT).
135  // 3. _M_refcount has three states:
136  // -1: leaked, one reference, no ref-copies allowed, non-const.
137  // 0: one reference, non-const.
138  // n>0: n + 1 references, operations require a lock, const.
139  // 4. All fields==0 is an empty string, given the extra storage
140  // beyond-the-end for a null terminator; thus, the shared
141  // empty string representation needs no constructor.
142 
143  struct _Rep_base
144  {
145  size_type _M_length;
146  size_type _M_capacity;
147  _Atomic_word _M_refcount;
148  };
149 
150  struct _Rep : _Rep_base
151  {
152  // Types:
153  typedef typename _Alloc::template rebind<char>::other _Raw_bytes_alloc;
154 
155  // (Public) Data members:
156 
157  // The maximum number of individual char_type elements of an
158  // individual string is determined by _S_max_size. This is the
159  // value that will be returned by max_size(). (Whereas npos
160  // is the maximum number of bytes the allocator can allocate.)
161  // If one was to divvy up the theoretical largest size string,
162  // with a terminating character and m _CharT elements, it'd
163  // look like this:
164  // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT)
165  // Solving for m:
166  // m = ((npos - sizeof(_Rep))/sizeof(CharT)) - 1
167  // In addition, this implementation quarters this amount.
168  static const size_type _S_max_size;
169  static const _CharT _S_terminal;
170 
171  // The following storage is init'd to 0 by the linker, resulting
172  // (carefully) in an empty string with one reference.
173  static size_type _S_empty_rep_storage[];
174 
175  static _Rep&
176  _S_empty_rep()
177  {
178  // NB: Mild hack to avoid strict-aliasing warnings. Note that
179  // _S_empty_rep_storage is never modified and the punning should
180  // be reasonably safe in this case.
181  void* __p = reinterpret_cast<void*>(&_S_empty_rep_storage);
182  return *reinterpret_cast<_Rep*>(__p);
183  }
184 
185  bool
186  _M_is_leaked() const
187  { return this->_M_refcount < 0; }
188 
189  bool
190  _M_is_shared() const
191  { return this->_M_refcount > 0; }
192 
193  void
194  _M_set_leaked()
195  { this->_M_refcount = -1; }
196 
197  void
198  _M_set_sharable()
199  { this->_M_refcount = 0; }
200 
201  void
202  _M_set_length_and_sharable(size_type __n)
203  {
204 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
205  if (__builtin_expect(this != &_S_empty_rep(), false))
206 #endif
207  {
208  this->_M_set_sharable(); // One reference.
209  this->_M_length = __n;
210  traits_type::assign(this->_M_refdata()[__n], _S_terminal);
211  // grrr. (per 21.3.4)
212  // You cannot leave those LWG people alone for a second.
213  }
214  }
215 
216  _CharT*
217  _M_refdata() throw()
218  { return reinterpret_cast<_CharT*>(this + 1); }
219 
220  _CharT*
221  _M_grab(const _Alloc& __alloc1, const _Alloc& __alloc2)
222  {
223  return (!_M_is_leaked() && __alloc1 == __alloc2)
224  ? _M_refcopy() : _M_clone(__alloc1);
225  }
226 
227  // Create & Destroy
228  static _Rep*
229  _S_create(size_type, size_type, const _Alloc&);
230 
231  void
232  _M_dispose(const _Alloc& __a)
233  {
234 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
235  if (__builtin_expect(this != &_S_empty_rep(), false))
236 #endif
237  {
238  // Be race-detector-friendly. For more info see bits/c++config.
239  _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount);
240  if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
241  -1) <= 0)
242  {
243  _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount);
244  _M_destroy(__a);
245  }
246  }
247  } // XXX MT
248 
249  void
250  _M_destroy(const _Alloc&) throw();
251 
252  _CharT*
253  _M_refcopy() throw()
254  {
255 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
256  if (__builtin_expect(this != &_S_empty_rep(), false))
257 #endif
258  __gnu_cxx::__atomic_add_dispatch(&this->_M_refcount, 1);
259  return _M_refdata();
260  } // XXX MT
261 
262  _CharT*
263  _M_clone(const _Alloc&, size_type __res = 0);
264  };
265 
266  // Use empty-base optimization: http://www.cantrip.org/emptyopt.html
267  struct _Alloc_hider : _Alloc
268  {
269  _Alloc_hider(_CharT* __dat, const _Alloc& __a)
270  : _Alloc(__a), _M_p(__dat) { }
271 
272  _CharT* _M_p; // The actual data.
273  };
274 
275  public:
276  // Data Members (public):
277  // NB: This is an unsigned type, and thus represents the maximum
278  // size that the allocator can hold.
279  /// Value returned by various member functions when they fail.
280  static const size_type npos = static_cast<size_type>(-1);
281 
282  private:
283  // Data Members (private):
284  mutable _Alloc_hider _M_dataplus;
285 
286  _CharT*
287  _M_data() const
288  { return _M_dataplus._M_p; }
289 
290  _CharT*
291  _M_data(_CharT* __p)
292  { return (_M_dataplus._M_p = __p); }
293 
294  _Rep*
295  _M_rep() const
296  { return &((reinterpret_cast<_Rep*> (_M_data()))[-1]); }
297 
298  // For the internal use we have functions similar to `begin'/`end'
299  // but they do not call _M_leak.
300  iterator
301  _M_ibegin() const
302  { return iterator(_M_data()); }
303 
304  iterator
305  _M_iend() const
306  { return iterator(_M_data() + this->size()); }
307 
308  void
309  _M_leak() // for use in begin() & non-const op[]
310  {
311  if (!_M_rep()->_M_is_leaked())
312  _M_leak_hard();
313  }
314 
315  size_type
316  _M_check(size_type __pos, const char* __s) const
317  {
318  if (__pos > this->size())
319  __throw_out_of_range(__N(__s));
320  return __pos;
321  }
322 
323  void
324  _M_check_length(size_type __n1, size_type __n2, const char* __s) const
325  {
326  if (this->max_size() - (this->size() - __n1) < __n2)
327  __throw_length_error(__N(__s));
328  }
329 
330  // NB: _M_limit doesn't check for a bad __pos value.
331  size_type
332  _M_limit(size_type __pos, size_type __off) const
333  {
334  const bool __testoff = __off < this->size() - __pos;
335  return __testoff ? __off : this->size() - __pos;
336  }
337 
338  // True if _Rep and source do not overlap.
339  bool
340  _M_disjunct(const _CharT* __s) const
341  {
342  return (less<const _CharT*>()(__s, _M_data())
343  || less<const _CharT*>()(_M_data() + this->size(), __s));
344  }
345 
346  // When __n = 1 way faster than the general multichar
347  // traits_type::copy/move/assign.
348  static void
349  _M_copy(_CharT* __d, const _CharT* __s, size_type __n)
350  {
351  if (__n == 1)
352  traits_type::assign(*__d, *__s);
353  else
354  traits_type::copy(__d, __s, __n);
355  }
356 
357  static void
358  _M_move(_CharT* __d, const _CharT* __s, size_type __n)
359  {
360  if (__n == 1)
361  traits_type::assign(*__d, *__s);
362  else
363  traits_type::move(__d, __s, __n);
364  }
365 
366  static void
367  _M_assign(_CharT* __d, size_type __n, _CharT __c)
368  {
369  if (__n == 1)
370  traits_type::assign(*__d, __c);
371  else
372  traits_type::assign(__d, __n, __c);
373  }
374 
375  // _S_copy_chars is a separate template to permit specialization
376  // to optimize for the common case of pointers as iterators.
377  template<class _Iterator>
378  static void
379  _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
380  {
381  for (; __k1 != __k2; ++__k1, ++__p)
382  traits_type::assign(*__p, *__k1); // These types are off.
383  }
384 
385  static void
386  _S_copy_chars(_CharT* __p, iterator __k1, iterator __k2)
387  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
388 
389  static void
390  _S_copy_chars(_CharT* __p, const_iterator __k1, const_iterator __k2)
391  { _S_copy_chars(__p, __k1.base(), __k2.base()); }
392 
393  static void
394  _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2)
395  { _M_copy(__p, __k1, __k2 - __k1); }
396 
397  static void
398  _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
399  { _M_copy(__p, __k1, __k2 - __k1); }
400 
401  static int
402  _S_compare(size_type __n1, size_type __n2)
403  {
404  const difference_type __d = difference_type(__n1 - __n2);
405 
406  if (__d > __gnu_cxx::__numeric_traits<int>::__max)
407  return __gnu_cxx::__numeric_traits<int>::__max;
408  else if (__d < __gnu_cxx::__numeric_traits<int>::__min)
409  return __gnu_cxx::__numeric_traits<int>::__min;
410  else
411  return int(__d);
412  }
413 
414  void
415  _M_mutate(size_type __pos, size_type __len1, size_type __len2);
416 
417  void
418  _M_leak_hard();
419 
420  static _Rep&
421  _S_empty_rep()
422  { return _Rep::_S_empty_rep(); }
423 
424  public:
425  // Construct/copy/destroy:
426  // NB: We overload ctors in some cases instead of using default
427  // arguments, per 17.4.4.4 para. 2 item 2.
428 
429  /**
430  * @brief Default constructor creates an empty string.
431  */
433 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
434  : _M_dataplus(_S_empty_rep()._M_refdata(), _Alloc()) { }
435 #else
436  : _M_dataplus(_S_construct(size_type(), _CharT(), _Alloc()), _Alloc()){ }
437 #endif
438 
439  /**
440  * @brief Construct an empty string using allocator @a a.
441  */
442  explicit
443  basic_string(const _Alloc& __a);
444 
445  // NB: per LWG issue 42, semantics different from IS:
446  /**
447  * @brief Construct string with copy of value of @a str.
448  * @param str Source string.
449  */
450  basic_string(const basic_string& __str);
451  /**
452  * @brief Construct string as copy of a substring.
453  * @param str Source string.
454  * @param pos Index of first character to copy from.
455  * @param n Number of characters to copy (default remainder).
456  */
457  basic_string(const basic_string& __str, size_type __pos,
458  size_type __n = npos);
459  /**
460  * @brief Construct string as copy of a substring.
461  * @param str Source string.
462  * @param pos Index of first character to copy from.
463  * @param n Number of characters to copy.
464  * @param a Allocator to use.
465  */
466  basic_string(const basic_string& __str, size_type __pos,
467  size_type __n, const _Alloc& __a);
468 
469  /**
470  * @brief Construct string initialized by a character %array.
471  * @param s Source character %array.
472  * @param n Number of characters to copy.
473  * @param a Allocator to use (default is default allocator).
474  *
475  * NB: @a s must have at least @a n characters, &apos;\\0&apos;
476  * has no special meaning.
477  */
478  basic_string(const _CharT* __s, size_type __n,
479  const _Alloc& __a = _Alloc());
480  /**
481  * @brief Construct string as copy of a C string.
482  * @param s Source C string.
483  * @param a Allocator to use (default is default allocator).
484  */
485  basic_string(const _CharT* __s, const _Alloc& __a = _Alloc());
486  /**
487  * @brief Construct string as multiple characters.
488  * @param n Number of characters.
489  * @param c Character to use.
490  * @param a Allocator to use (default is default allocator).
491  */
492  basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc());
493 
494 #ifdef __GXX_EXPERIMENTAL_CXX0X__
495  /**
496  * @brief Move construct string.
497  * @param str Source string.
498  *
499  * The newly-created string contains the exact contents of @a str.
500  * @a str is a valid, but unspecified string.
501  **/
503  : _M_dataplus(__str._M_dataplus)
504  {
505 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
506  __str._M_data(_S_empty_rep()._M_refdata());
507 #else
508  __str._M_data(_S_construct(size_type(), _CharT(), get_allocator()));
509 #endif
510  }
511 
512  /**
513  * @brief Construct string from an initializer %list.
514  * @param l std::initializer_list of characters.
515  * @param a Allocator to use (default is default allocator).
516  */
517  basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc());
518 #endif // __GXX_EXPERIMENTAL_CXX0X__
519 
520  /**
521  * @brief Construct string as copy of a range.
522  * @param beg Start of range.
523  * @param end End of range.
524  * @param a Allocator to use (default is default allocator).
525  */
526  template<class _InputIterator>
527  basic_string(_InputIterator __beg, _InputIterator __end,
528  const _Alloc& __a = _Alloc());
529 
530  /**
531  * @brief Destroy the string instance.
532  */
534  { _M_rep()->_M_dispose(this->get_allocator()); }
535 
536  /**
537  * @brief Assign the value of @a str to this string.
538  * @param str Source string.
539  */
540  basic_string&
541  operator=(const basic_string& __str)
542  { return this->assign(__str); }
543 
544  /**
545  * @brief Copy contents of @a s into this string.
546  * @param s Source null-terminated string.
547  */
548  basic_string&
549  operator=(const _CharT* __s)
550  { return this->assign(__s); }
551 
552  /**
553  * @brief Set value to string of length 1.
554  * @param c Source character.
555  *
556  * Assigning to a character makes this string length 1 and
557  * (*this)[0] == @a c.
558  */
559  basic_string&
560  operator=(_CharT __c)
561  {
562  this->assign(1, __c);
563  return *this;
564  }
565 
566 #ifdef __GXX_EXPERIMENTAL_CXX0X__
567  /**
568  * @brief Move assign the value of @a str to this string.
569  * @param str Source string.
570  *
571  * The contents of @a str are moved into this string (without copying).
572  * @a str is a valid, but unspecified string.
573  **/
574  basic_string&
576  {
577  // NB: DR 1204.
578  this->swap(__str);
579  return *this;
580  }
581 
582  /**
583  * @brief Set value to string constructed from initializer %list.
584  * @param l std::initializer_list.
585  */
586  basic_string&
588  {
589  this->assign(__l.begin(), __l.size());
590  return *this;
591  }
592 #endif // __GXX_EXPERIMENTAL_CXX0X__
593 
594  // Iterators:
595  /**
596  * Returns a read/write iterator that points to the first character in
597  * the %string. Unshares the string.
598  */
599  iterator
601  {
602  _M_leak();
603  return iterator(_M_data());
604  }
605 
606  /**
607  * Returns a read-only (constant) iterator that points to the first
608  * character in the %string.
609  */
610  const_iterator
611  begin() const
612  { return const_iterator(_M_data()); }
613 
614  /**
615  * Returns a read/write iterator that points one past the last
616  * character in the %string. Unshares the string.
617  */
618  iterator
619  end()
620  {
621  _M_leak();
622  return iterator(_M_data() + this->size());
623  }
624 
625  /**
626  * Returns a read-only (constant) iterator that points one past the
627  * last character in the %string.
628  */
629  const_iterator
630  end() const
631  { return const_iterator(_M_data() + this->size()); }
632 
633  /**
634  * Returns a read/write reverse iterator that points to the last
635  * character in the %string. Iteration is done in reverse element
636  * order. Unshares the string.
637  */
640  { return reverse_iterator(this->end()); }
641 
642  /**
643  * Returns a read-only (constant) reverse iterator that points
644  * to the last character in the %string. Iteration is done in
645  * reverse element order.
646  */
647  const_reverse_iterator
648  rbegin() const
649  { return const_reverse_iterator(this->end()); }
650 
651  /**
652  * Returns a read/write reverse iterator that points to one before the
653  * first character in the %string. Iteration is done in reverse
654  * element order. Unshares the string.
655  */
658  { return reverse_iterator(this->begin()); }
659 
660  /**
661  * Returns a read-only (constant) reverse iterator that points
662  * to one before the first character in the %string. Iteration
663  * is done in reverse element order.
664  */
665  const_reverse_iterator
666  rend() const
667  { return const_reverse_iterator(this->begin()); }
668 
669 #ifdef __GXX_EXPERIMENTAL_CXX0X__
670  /**
671  * Returns a read-only (constant) iterator that points to the first
672  * character in the %string.
673  */
674  const_iterator
675  cbegin() const
676  { return const_iterator(this->_M_data()); }
677 
678  /**
679  * Returns a read-only (constant) iterator that points one past the
680  * last character in the %string.
681  */
682  const_iterator
683  cend() const
684  { return const_iterator(this->_M_data() + this->size()); }
685 
686  /**
687  * Returns a read-only (constant) reverse iterator that points
688  * to the last character in the %string. Iteration is done in
689  * reverse element order.
690  */
691  const_reverse_iterator
692  crbegin() const
693  { return const_reverse_iterator(this->end()); }
694 
695  /**
696  * Returns a read-only (constant) reverse iterator that points
697  * to one before the first character in the %string. Iteration
698  * is done in reverse element order.
699  */
700  const_reverse_iterator
701  crend() const
702  { return const_reverse_iterator(this->begin()); }
703 #endif
704 
705  public:
706  // Capacity:
707  /// Returns the number of characters in the string, not including any
708  /// null-termination.
709  size_type
710  size() const
711  { return _M_rep()->_M_length; }
712 
713  /// Returns the number of characters in the string, not including any
714  /// null-termination.
715  size_type
716  length() const
717  { return _M_rep()->_M_length; }
718 
719  /// Returns the size() of the largest possible %string.
720  size_type
721  max_size() const
722  { return _Rep::_S_max_size; }
723 
724  /**
725  * @brief Resizes the %string to the specified number of characters.
726  * @param n Number of characters the %string should contain.
727  * @param c Character to fill any new elements.
728  *
729  * This function will %resize the %string to the specified
730  * number of characters. If the number is smaller than the
731  * %string's current size the %string is truncated, otherwise
732  * the %string is extended and new elements are %set to @a c.
733  */
734  void
735  resize(size_type __n, _CharT __c);
736 
737  /**
738  * @brief Resizes the %string to the specified number of characters.
739  * @param n Number of characters the %string should contain.
740  *
741  * This function will resize the %string to the specified length. If
742  * the new size is smaller than the %string's current size the %string
743  * is truncated, otherwise the %string is extended and new characters
744  * are default-constructed. For basic types such as char, this means
745  * setting them to 0.
746  */
747  void
748  resize(size_type __n)
749  { this->resize(__n, _CharT()); }
750 
751 #ifdef __GXX_EXPERIMENTAL_CXX0X__
752  /// A non-binding request to reduce capacity() to size().
753  void
755  {
756  __try
757  { reserve(0); }
758  __catch(...)
759  { }
760  }
761 #endif
762 
763  /**
764  * Returns the total number of characters that the %string can hold
765  * before needing to allocate more memory.
766  */
767  size_type
768  capacity() const
769  { return _M_rep()->_M_capacity; }
770 
771  /**
772  * @brief Attempt to preallocate enough memory for specified number of
773  * characters.
774  * @param res_arg Number of characters required.
775  * @throw std::length_error If @a res_arg exceeds @c max_size().
776  *
777  * This function attempts to reserve enough memory for the
778  * %string to hold the specified number of characters. If the
779  * number requested is more than max_size(), length_error is
780  * thrown.
781  *
782  * The advantage of this function is that if optimal code is a
783  * necessity and the user can determine the string length that will be
784  * required, the user can reserve the memory in %advance, and thus
785  * prevent a possible reallocation of memory and copying of %string
786  * data.
787  */
788  void
789  reserve(size_type __res_arg = 0);
790 
791  /**
792  * Erases the string, making it empty.
793  */
794  void
796  { _M_mutate(0, this->size(), 0); }
797 
798  /**
799  * Returns true if the %string is empty. Equivalent to
800  * <code>*this == ""</code>.
801  */
802  bool
803  empty() const
804  { return this->size() == 0; }
805 
806  // Element access:
807  /**
808  * @brief Subscript access to the data contained in the %string.
809  * @param pos The index of the character to access.
810  * @return Read-only (constant) reference to the character.
811  *
812  * This operator allows for easy, array-style, data access.
813  * Note that data access with this operator is unchecked and
814  * out_of_range lookups are not defined. (For checked lookups
815  * see at().)
816  */
817  const_reference
818  operator[] (size_type __pos) const
819  {
820  _GLIBCXX_DEBUG_ASSERT(__pos <= size());
821  return _M_data()[__pos];
822  }
823 
824  /**
825  * @brief Subscript access to the data contained in the %string.
826  * @param pos The index of the character to access.
827  * @return Read/write reference to the character.
828  *
829  * This operator allows for easy, array-style, data access.
830  * Note that data access with this operator is unchecked and
831  * out_of_range lookups are not defined. (For checked lookups
832  * see at().) Unshares the string.
833  */
834  reference
835  operator[](size_type __pos)
836  {
837  // allow pos == size() as v3 extension:
838  _GLIBCXX_DEBUG_ASSERT(__pos <= size());
839  // but be strict in pedantic mode:
840  _GLIBCXX_DEBUG_PEDASSERT(__pos < size());
841  _M_leak();
842  return _M_data()[__pos];
843  }
844 
845  /**
846  * @brief Provides access to the data contained in the %string.
847  * @param n The index of the character to access.
848  * @return Read-only (const) reference to the character.
849  * @throw std::out_of_range If @a n is an invalid index.
850  *
851  * This function provides for safer data access. The parameter is
852  * first checked that it is in the range of the string. The function
853  * throws out_of_range if the check fails.
854  */
855  const_reference
856  at(size_type __n) const
857  {
858  if (__n >= this->size())
859  __throw_out_of_range(__N("basic_string::at"));
860  return _M_data()[__n];
861  }
862 
863 #ifdef __GXX_EXPERIMENTAL_CXX0X__
864  /**
865  * Returns a read/write reference to the data at the first
866  * element of the %string.
867  */
868  reference
870  { return operator[](0); }
871 
872  /**
873  * Returns a read-only (constant) reference to the data at the first
874  * element of the %string.
875  */
876  const_reference
877  front() const
878  { return operator[](0); }
879 
880  /**
881  * Returns a read/write reference to the data at the last
882  * element of the %string.
883  */
884  reference
886  { return operator[](this->size() - 1); }
887 
888  /**
889  * Returns a read-only (constant) reference to the data at the
890  * last element of the %string.
891  */
892  const_reference
893  back() const
894  { return operator[](this->size() - 1); }
895 #endif
896 
897  /**
898  * @brief Provides access to the data contained in the %string.
899  * @param n The index of the character to access.
900  * @return Read/write reference to the character.
901  * @throw std::out_of_range If @a n is an invalid index.
902  *
903  * This function provides for safer data access. The parameter is
904  * first checked that it is in the range of the string. The function
905  * throws out_of_range if the check fails. Success results in
906  * unsharing the string.
907  */
908  reference
909  at(size_type __n)
910  {
911  if (__n >= size())
912  __throw_out_of_range(__N("basic_string::at"));
913  _M_leak();
914  return _M_data()[__n];
915  }
916 
917  // Modifiers:
918  /**
919  * @brief Append a string to this string.
920  * @param str The string to append.
921  * @return Reference to this string.
922  */
923  basic_string&
924  operator+=(const basic_string& __str)
925  { return this->append(__str); }
926 
927  /**
928  * @brief Append a C string.
929  * @param s The C string to append.
930  * @return Reference to this string.
931  */
932  basic_string&
933  operator+=(const _CharT* __s)
934  { return this->append(__s); }
935 
936  /**
937  * @brief Append a character.
938  * @param c The character to append.
939  * @return Reference to this string.
940  */
941  basic_string&
942  operator+=(_CharT __c)
943  {
944  this->push_back(__c);
945  return *this;
946  }
947 
948 #ifdef __GXX_EXPERIMENTAL_CXX0X__
949  /**
950  * @brief Append an initializer_list of characters.
951  * @param l The initializer_list of characters to be appended.
952  * @return Reference to this string.
953  */
954  basic_string&
956  { return this->append(__l.begin(), __l.size()); }
957 #endif // __GXX_EXPERIMENTAL_CXX0X__
958 
959  /**
960  * @brief Append a string to this string.
961  * @param str The string to append.
962  * @return Reference to this string.
963  */
964  basic_string&
965  append(const basic_string& __str);
966 
967  /**
968  * @brief Append a substring.
969  * @param str The string to append.
970  * @param pos Index of the first character of str to append.
971  * @param n The number of characters to append.
972  * @return Reference to this string.
973  * @throw std::out_of_range if @a pos is not a valid index.
974  *
975  * This function appends @a n characters from @a str starting at @a pos
976  * to this string. If @a n is is larger than the number of available
977  * characters in @a str, the remainder of @a str is appended.
978  */
979  basic_string&
980  append(const basic_string& __str, size_type __pos, size_type __n);
981 
982  /**
983  * @brief Append a C substring.
984  * @param s The C string to append.
985  * @param n The number of characters to append.
986  * @return Reference to this string.
987  */
988  basic_string&
989  append(const _CharT* __s, size_type __n);
990 
991  /**
992  * @brief Append a C string.
993  * @param s The C string to append.
994  * @return Reference to this string.
995  */
996  basic_string&
997  append(const _CharT* __s)
998  {
999  __glibcxx_requires_string(__s);
1000  return this->append(__s, traits_type::length(__s));
1001  }
1002 
1003  /**
1004  * @brief Append multiple characters.
1005  * @param n The number of characters to append.
1006  * @param c The character to use.
1007  * @return Reference to this string.
1008  *
1009  * Appends n copies of c to this string.
1010  */
1011  basic_string&
1012  append(size_type __n, _CharT __c);
1013 
1014 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1015  /**
1016  * @brief Append an initializer_list of characters.
1017  * @param l The initializer_list of characters to append.
1018  * @return Reference to this string.
1019  */
1020  basic_string&
1022  { return this->append(__l.begin(), __l.size()); }
1023 #endif // __GXX_EXPERIMENTAL_CXX0X__
1024 
1025  /**
1026  * @brief Append a range of characters.
1027  * @param first Iterator referencing the first character to append.
1028  * @param last Iterator marking the end of the range.
1029  * @return Reference to this string.
1030  *
1031  * Appends characters in the range [first,last) to this string.
1032  */
1033  template<class _InputIterator>
1034  basic_string&
1035  append(_InputIterator __first, _InputIterator __last)
1036  { return this->replace(_M_iend(), _M_iend(), __first, __last); }
1037 
1038  /**
1039  * @brief Append a single character.
1040  * @param c Character to append.
1041  */
1042  void
1043  push_back(_CharT __c)
1044  {
1045  const size_type __len = 1 + this->size();
1046  if (__len > this->capacity() || _M_rep()->_M_is_shared())
1047  this->reserve(__len);
1048  traits_type::assign(_M_data()[this->size()], __c);
1049  _M_rep()->_M_set_length_and_sharable(__len);
1050  }
1051 
1052  /**
1053  * @brief Set value to contents of another string.
1054  * @param str Source string to use.
1055  * @return Reference to this string.
1056  */
1057  basic_string&
1058  assign(const basic_string& __str);
1059 
1060 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1061  /**
1062  * @brief Set value to contents of another string.
1063  * @param str Source string to use.
1064  * @return Reference to this string.
1065  *
1066  * This function sets this string to the exact contents of @a str.
1067  * @a str is a valid, but unspecified string.
1068  */
1069  basic_string&
1071  {
1072  this->swap(__str);
1073  return *this;
1074  }
1075 #endif // __GXX_EXPERIMENTAL_CXX0X__
1076 
1077  /**
1078  * @brief Set value to a substring of a string.
1079  * @param str The string to use.
1080  * @param pos Index of the first character of str.
1081  * @param n Number of characters to use.
1082  * @return Reference to this string.
1083  * @throw std::out_of_range if @a pos is not a valid index.
1084  *
1085  * This function sets this string to the substring of @a str consisting
1086  * of @a n characters at @a pos. If @a n is is larger than the number
1087  * of available characters in @a str, the remainder of @a str is used.
1088  */
1089  basic_string&
1090  assign(const basic_string& __str, size_type __pos, size_type __n)
1091  { return this->assign(__str._M_data()
1092  + __str._M_check(__pos, "basic_string::assign"),
1093  __str._M_limit(__pos, __n)); }
1094 
1095  /**
1096  * @brief Set value to a C substring.
1097  * @param s The C string to use.
1098  * @param n Number of characters to use.
1099  * @return Reference to this string.
1100  *
1101  * This function sets the value of this string to the first @a n
1102  * characters of @a s. If @a n is is larger than the number of
1103  * available characters in @a s, the remainder of @a s is used.
1104  */
1105  basic_string&
1106  assign(const _CharT* __s, size_type __n);
1107 
1108  /**
1109  * @brief Set value to contents of a C string.
1110  * @param s The C string to use.
1111  * @return Reference to this string.
1112  *
1113  * This function sets the value of this string to the value of @a s.
1114  * The data is copied, so there is no dependence on @a s once the
1115  * function returns.
1116  */
1117  basic_string&
1118  assign(const _CharT* __s)
1119  {
1120  __glibcxx_requires_string(__s);
1121  return this->assign(__s, traits_type::length(__s));
1122  }
1123 
1124  /**
1125  * @brief Set value to multiple characters.
1126  * @param n Length of the resulting string.
1127  * @param c The character to use.
1128  * @return Reference to this string.
1129  *
1130  * This function sets the value of this string to @a n copies of
1131  * character @a c.
1132  */
1133  basic_string&
1134  assign(size_type __n, _CharT __c)
1135  { return _M_replace_aux(size_type(0), this->size(), __n, __c); }
1136 
1137  /**
1138  * @brief Set value to a range of characters.
1139  * @param first Iterator referencing the first character to append.
1140  * @param last Iterator marking the end of the range.
1141  * @return Reference to this string.
1142  *
1143  * Sets value of string to characters in the range [first,last).
1144  */
1145  template<class _InputIterator>
1146  basic_string&
1147  assign(_InputIterator __first, _InputIterator __last)
1148  { return this->replace(_M_ibegin(), _M_iend(), __first, __last); }
1149 
1150 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1151  /**
1152  * @brief Set value to an initializer_list of characters.
1153  * @param l The initializer_list of characters to assign.
1154  * @return Reference to this string.
1155  */
1156  basic_string&
1158  { return this->assign(__l.begin(), __l.size()); }
1159 #endif // __GXX_EXPERIMENTAL_CXX0X__
1160 
1161  /**
1162  * @brief Insert multiple characters.
1163  * @param p Iterator referencing location in string to insert at.
1164  * @param n Number of characters to insert
1165  * @param c The character to insert.
1166  * @throw std::length_error If new length exceeds @c max_size().
1167  *
1168  * Inserts @a n copies of character @a c starting at the position
1169  * referenced by iterator @a p. If adding characters causes the length
1170  * to exceed max_size(), length_error is thrown. The value of the
1171  * string doesn't change if an error is thrown.
1172  */
1173  void
1174  insert(iterator __p, size_type __n, _CharT __c)
1175  { this->replace(__p, __p, __n, __c); }
1176 
1177  /**
1178  * @brief Insert a range of characters.
1179  * @param p Iterator referencing location in string to insert at.
1180  * @param beg Start of range.
1181  * @param end End of range.
1182  * @throw std::length_error If new length exceeds @c max_size().
1183  *
1184  * Inserts characters in range [beg,end). If adding characters causes
1185  * the length to exceed max_size(), length_error is thrown. The value
1186  * of the string doesn't change if an error is thrown.
1187  */
1188  template<class _InputIterator>
1189  void
1190  insert(iterator __p, _InputIterator __beg, _InputIterator __end)
1191  { this->replace(__p, __p, __beg, __end); }
1192 
1193 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1194  /**
1195  * @brief Insert an initializer_list of characters.
1196  * @param p Iterator referencing location in string to insert at.
1197  * @param l The initializer_list of characters to insert.
1198  * @throw std::length_error If new length exceeds @c max_size().
1199  */
1200  void
1202  {
1203  _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
1204  this->insert(__p - _M_ibegin(), __l.begin(), __l.size());
1205  }
1206 #endif // __GXX_EXPERIMENTAL_CXX0X__
1207 
1208  /**
1209  * @brief Insert value of a string.
1210  * @param pos1 Iterator referencing location in string to insert at.
1211  * @param str The string to insert.
1212  * @return Reference to this string.
1213  * @throw std::length_error If new length exceeds @c max_size().
1214  *
1215  * Inserts value of @a str starting at @a pos1. If adding characters
1216  * causes the length to exceed max_size(), length_error is thrown. The
1217  * value of the string doesn't change if an error is thrown.
1218  */
1219  basic_string&
1220  insert(size_type __pos1, const basic_string& __str)
1221  { return this->insert(__pos1, __str, size_type(0), __str.size()); }
1222 
1223  /**
1224  * @brief Insert a substring.
1225  * @param pos1 Iterator referencing location in string to insert at.
1226  * @param str The string to insert.
1227  * @param pos2 Start of characters in str to insert.
1228  * @param n Number of characters to insert.
1229  * @return Reference to this string.
1230  * @throw std::length_error If new length exceeds @c max_size().
1231  * @throw std::out_of_range If @a pos1 > size() or
1232  * @a pos2 > @a str.size().
1233  *
1234  * Starting at @a pos1, insert @a n character of @a str beginning with
1235  * @a pos2. If adding characters causes the length to exceed
1236  * max_size(), length_error is thrown. If @a pos1 is beyond the end of
1237  * this string or @a pos2 is beyond the end of @a str, out_of_range is
1238  * thrown. The value of the string doesn't change if an error is
1239  * thrown.
1240  */
1241  basic_string&
1242  insert(size_type __pos1, const basic_string& __str,
1243  size_type __pos2, size_type __n)
1244  { return this->insert(__pos1, __str._M_data()
1245  + __str._M_check(__pos2, "basic_string::insert"),
1246  __str._M_limit(__pos2, __n)); }
1247 
1248  /**
1249  * @brief Insert a C substring.
1250  * @param pos Iterator referencing location in string to insert at.
1251  * @param s The C string to insert.
1252  * @param n The number of characters to insert.
1253  * @return Reference to this string.
1254  * @throw std::length_error If new length exceeds @c max_size().
1255  * @throw std::out_of_range If @a pos is beyond the end of this
1256  * string.
1257  *
1258  * Inserts the first @a n characters of @a s starting at @a pos. If
1259  * adding characters causes the length to exceed max_size(),
1260  * length_error is thrown. If @a pos is beyond end(), out_of_range is
1261  * thrown. The value of the string doesn't change if an error is
1262  * thrown.
1263  */
1264  basic_string&
1265  insert(size_type __pos, const _CharT* __s, size_type __n);
1266 
1267  /**
1268  * @brief Insert a C string.
1269  * @param pos Iterator referencing location in string to insert at.
1270  * @param s The C string to insert.
1271  * @return Reference to this string.
1272  * @throw std::length_error If new length exceeds @c max_size().
1273  * @throw std::out_of_range If @a pos is beyond the end of this
1274  * string.
1275  *
1276  * Inserts the first @a n characters of @a s starting at @a pos. If
1277  * adding characters causes the length to exceed max_size(),
1278  * length_error is thrown. If @a pos is beyond end(), out_of_range is
1279  * thrown. The value of the string doesn't change if an error is
1280  * thrown.
1281  */
1282  basic_string&
1283  insert(size_type __pos, const _CharT* __s)
1284  {
1285  __glibcxx_requires_string(__s);
1286  return this->insert(__pos, __s, traits_type::length(__s));
1287  }
1288 
1289  /**
1290  * @brief Insert multiple characters.
1291  * @param pos Index in string to insert at.
1292  * @param n Number of characters to insert
1293  * @param c The character to insert.
1294  * @return Reference to this string.
1295  * @throw std::length_error If new length exceeds @c max_size().
1296  * @throw std::out_of_range If @a pos is beyond the end of this
1297  * string.
1298  *
1299  * Inserts @a n copies of character @a c starting at index @a pos. If
1300  * adding characters causes the length to exceed max_size(),
1301  * length_error is thrown. If @a pos > length(), out_of_range is
1302  * thrown. The value of the string doesn't change if an error is
1303  * thrown.
1304  */
1305  basic_string&
1306  insert(size_type __pos, size_type __n, _CharT __c)
1307  { return _M_replace_aux(_M_check(__pos, "basic_string::insert"),
1308  size_type(0), __n, __c); }
1309 
1310  /**
1311  * @brief Insert one character.
1312  * @param p Iterator referencing position in string to insert at.
1313  * @param c The character to insert.
1314  * @return Iterator referencing newly inserted char.
1315  * @throw std::length_error If new length exceeds @c max_size().
1316  *
1317  * Inserts character @a c at position referenced by @a p. If adding
1318  * character causes the length to exceed max_size(), length_error is
1319  * thrown. If @a p is beyond end of string, out_of_range is thrown.
1320  * The value of the string doesn't change if an error is thrown.
1321  */
1322  iterator
1323  insert(iterator __p, _CharT __c)
1324  {
1325  _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
1326  const size_type __pos = __p - _M_ibegin();
1327  _M_replace_aux(__pos, size_type(0), size_type(1), __c);
1328  _M_rep()->_M_set_leaked();
1329  return iterator(_M_data() + __pos);
1330  }
1331 
1332  /**
1333  * @brief Remove characters.
1334  * @param pos Index of first character to remove (default 0).
1335  * @param n Number of characters to remove (default remainder).
1336  * @return Reference to this string.
1337  * @throw std::out_of_range If @a pos is beyond the end of this
1338  * string.
1339  *
1340  * Removes @a n characters from this string starting at @a pos. The
1341  * length of the string is reduced by @a n. If there are < @a n
1342  * characters to remove, the remainder of the string is truncated. If
1343  * @a p is beyond end of string, out_of_range is thrown. The value of
1344  * the string doesn't change if an error is thrown.
1345  */
1346  basic_string&
1347  erase(size_type __pos = 0, size_type __n = npos)
1348  {
1349  _M_mutate(_M_check(__pos, "basic_string::erase"),
1350  _M_limit(__pos, __n), size_type(0));
1351  return *this;
1352  }
1353 
1354  /**
1355  * @brief Remove one character.
1356  * @param position Iterator referencing the character to remove.
1357  * @return iterator referencing same location after removal.
1358  *
1359  * Removes the character at @a position from this string. The value
1360  * of the string doesn't change if an error is thrown.
1361  */
1362  iterator
1363  erase(iterator __position)
1364  {
1365  _GLIBCXX_DEBUG_PEDASSERT(__position >= _M_ibegin()
1366  && __position < _M_iend());
1367  const size_type __pos = __position - _M_ibegin();
1368  _M_mutate(__pos, size_type(1), size_type(0));
1369  _M_rep()->_M_set_leaked();
1370  return iterator(_M_data() + __pos);
1371  }
1372 
1373  /**
1374  * @brief Remove a range of characters.
1375  * @param first Iterator referencing the first character to remove.
1376  * @param last Iterator referencing the end of the range.
1377  * @return Iterator referencing location of first after removal.
1378  *
1379  * Removes the characters in the range [first,last) from this string.
1380  * The value of the string doesn't change if an error is thrown.
1381  */
1382  iterator
1383  erase(iterator __first, iterator __last);
1384 
1385  /**
1386  * @brief Replace characters with value from another string.
1387  * @param pos Index of first character to replace.
1388  * @param n Number of characters to be replaced.
1389  * @param str String to insert.
1390  * @return Reference to this string.
1391  * @throw std::out_of_range If @a pos is beyond the end of this
1392  * string.
1393  * @throw std::length_error If new length exceeds @c max_size().
1394  *
1395  * Removes the characters in the range [pos,pos+n) from this string.
1396  * In place, the value of @a str is inserted. If @a pos is beyond end
1397  * of string, out_of_range is thrown. If the length of the result
1398  * exceeds max_size(), length_error is thrown. The value of the string
1399  * doesn't change if an error is thrown.
1400  */
1401  basic_string&
1402  replace(size_type __pos, size_type __n, const basic_string& __str)
1403  { return this->replace(__pos, __n, __str._M_data(), __str.size()); }
1404 
1405  /**
1406  * @brief Replace characters with value from another string.
1407  * @param pos1 Index of first character to replace.
1408  * @param n1 Number of characters to be replaced.
1409  * @param str String to insert.
1410  * @param pos2 Index of first character of str to use.
1411  * @param n2 Number of characters from str to use.
1412  * @return Reference to this string.
1413  * @throw std::out_of_range If @a pos1 > size() or @a pos2 >
1414  * str.size().
1415  * @throw std::length_error If new length exceeds @c max_size().
1416  *
1417  * Removes the characters in the range [pos1,pos1 + n) from this
1418  * string. In place, the value of @a str is inserted. If @a pos is
1419  * beyond end of string, out_of_range is thrown. If the length of the
1420  * result exceeds max_size(), length_error is thrown. The value of the
1421  * string doesn't change if an error is thrown.
1422  */
1423  basic_string&
1424  replace(size_type __pos1, size_type __n1, const basic_string& __str,
1425  size_type __pos2, size_type __n2)
1426  { return this->replace(__pos1, __n1, __str._M_data()
1427  + __str._M_check(__pos2, "basic_string::replace"),
1428  __str._M_limit(__pos2, __n2)); }
1429 
1430  /**
1431  * @brief Replace characters with value of a C substring.
1432  * @param pos Index of first character to replace.
1433  * @param n1 Number of characters to be replaced.
1434  * @param s C string to insert.
1435  * @param n2 Number of characters from @a s to use.
1436  * @return Reference to this string.
1437  * @throw std::out_of_range If @a pos1 > size().
1438  * @throw std::length_error If new length exceeds @c max_size().
1439  *
1440  * Removes the characters in the range [pos,pos + n1) from this string.
1441  * In place, the first @a n2 characters of @a s are inserted, or all
1442  * of @a s if @a n2 is too large. If @a pos is beyond end of string,
1443  * out_of_range is thrown. If the length of result exceeds max_size(),
1444  * length_error is thrown. The value of the string doesn't change if
1445  * an error is thrown.
1446  */
1447  basic_string&
1448  replace(size_type __pos, size_type __n1, const _CharT* __s,
1449  size_type __n2);
1450 
1451  /**
1452  * @brief Replace characters with value of a C string.
1453  * @param pos Index of first character to replace.
1454  * @param n1 Number of characters to be replaced.
1455  * @param s C string to insert.
1456  * @return Reference to this string.
1457  * @throw std::out_of_range If @a pos > size().
1458  * @throw std::length_error If new length exceeds @c max_size().
1459  *
1460  * Removes the characters in the range [pos,pos + n1) from this string.
1461  * In place, the characters of @a s are inserted. If @a pos is beyond
1462  * end of string, out_of_range is thrown. If the length of result
1463  * exceeds max_size(), length_error is thrown. The value of the string
1464  * doesn't change if an error is thrown.
1465  */
1466  basic_string&
1467  replace(size_type __pos, size_type __n1, const _CharT* __s)
1468  {
1469  __glibcxx_requires_string(__s);
1470  return this->replace(__pos, __n1, __s, traits_type::length(__s));
1471  }
1472 
1473  /**
1474  * @brief Replace characters with multiple characters.
1475  * @param pos Index of first character to replace.
1476  * @param n1 Number of characters to be replaced.
1477  * @param n2 Number of characters to insert.
1478  * @param c Character to insert.
1479  * @return Reference to this string.
1480  * @throw std::out_of_range If @a pos > size().
1481  * @throw std::length_error If new length exceeds @c max_size().
1482  *
1483  * Removes the characters in the range [pos,pos + n1) from this string.
1484  * In place, @a n2 copies of @a c are inserted. If @a pos is beyond
1485  * end of string, out_of_range is thrown. If the length of result
1486  * exceeds max_size(), length_error is thrown. The value of the string
1487  * doesn't change if an error is thrown.
1488  */
1489  basic_string&
1490  replace(size_type __pos, size_type __n1, size_type __n2, _CharT __c)
1491  { return _M_replace_aux(_M_check(__pos, "basic_string::replace"),
1492  _M_limit(__pos, __n1), __n2, __c); }
1493 
1494  /**
1495  * @brief Replace range of characters with string.
1496  * @param i1 Iterator referencing start of range to replace.
1497  * @param i2 Iterator referencing end of range to replace.
1498  * @param str String value to insert.
1499  * @return Reference to this string.
1500  * @throw std::length_error If new length exceeds @c max_size().
1501  *
1502  * Removes the characters in the range [i1,i2). In place, the value of
1503  * @a str is inserted. If the length of result exceeds max_size(),
1504  * length_error is thrown. The value of the string doesn't change if
1505  * an error is thrown.
1506  */
1507  basic_string&
1508  replace(iterator __i1, iterator __i2, const basic_string& __str)
1509  { return this->replace(__i1, __i2, __str._M_data(), __str.size()); }
1510 
1511  /**
1512  * @brief Replace range of characters with C substring.
1513  * @param i1 Iterator referencing start of range to replace.
1514  * @param i2 Iterator referencing end of range to replace.
1515  * @param s C string value to insert.
1516  * @param n Number of characters from s to insert.
1517  * @return Reference to this string.
1518  * @throw std::length_error If new length exceeds @c max_size().
1519  *
1520  * Removes the characters in the range [i1,i2). In place, the first @a
1521  * n characters of @a s are inserted. If the length of result exceeds
1522  * max_size(), length_error is thrown. The value of the string doesn't
1523  * change if an error is thrown.
1524  */
1525  basic_string&
1526  replace(iterator __i1, iterator __i2, const _CharT* __s, size_type __n)
1527  {
1528  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1529  && __i2 <= _M_iend());
1530  return this->replace(__i1 - _M_ibegin(), __i2 - __i1, __s, __n);
1531  }
1532 
1533  /**
1534  * @brief Replace range of characters with C string.
1535  * @param i1 Iterator referencing start of range to replace.
1536  * @param i2 Iterator referencing end of range to replace.
1537  * @param s C string value to insert.
1538  * @return Reference to this string.
1539  * @throw std::length_error If new length exceeds @c max_size().
1540  *
1541  * Removes the characters in the range [i1,i2). In place, the
1542  * characters of @a s are inserted. If the length of result exceeds
1543  * max_size(), length_error is thrown. The value of the string doesn't
1544  * change if an error is thrown.
1545  */
1546  basic_string&
1547  replace(iterator __i1, iterator __i2, const _CharT* __s)
1548  {
1549  __glibcxx_requires_string(__s);
1550  return this->replace(__i1, __i2, __s, traits_type::length(__s));
1551  }
1552 
1553  /**
1554  * @brief Replace range of characters with multiple characters
1555  * @param i1 Iterator referencing start of range to replace.
1556  * @param i2 Iterator referencing end of range to replace.
1557  * @param n Number of characters to insert.
1558  * @param c Character to insert.
1559  * @return Reference to this string.
1560  * @throw std::length_error If new length exceeds @c max_size().
1561  *
1562  * Removes the characters in the range [i1,i2). In place, @a n copies
1563  * of @a c are inserted. If the length of result exceeds max_size(),
1564  * length_error is thrown. The value of the string doesn't change if
1565  * an error is thrown.
1566  */
1567  basic_string&
1568  replace(iterator __i1, iterator __i2, size_type __n, _CharT __c)
1569  {
1570  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1571  && __i2 <= _M_iend());
1572  return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __c);
1573  }
1574 
1575  /**
1576  * @brief Replace range of characters with range.
1577  * @param i1 Iterator referencing start of range to replace.
1578  * @param i2 Iterator referencing end of range to replace.
1579  * @param k1 Iterator referencing start of range to insert.
1580  * @param k2 Iterator referencing end of range to insert.
1581  * @return Reference to this string.
1582  * @throw std::length_error If new length exceeds @c max_size().
1583  *
1584  * Removes the characters in the range [i1,i2). In place, characters
1585  * in the range [k1,k2) are inserted. If the length of result exceeds
1586  * max_size(), length_error is thrown. The value of the string doesn't
1587  * change if an error is thrown.
1588  */
1589  template<class _InputIterator>
1590  basic_string&
1591  replace(iterator __i1, iterator __i2,
1592  _InputIterator __k1, _InputIterator __k2)
1593  {
1594  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1595  && __i2 <= _M_iend());
1596  __glibcxx_requires_valid_range(__k1, __k2);
1597  typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1598  return _M_replace_dispatch(__i1, __i2, __k1, __k2, _Integral());
1599  }
1600 
1601  // Specializations for the common case of pointer and iterator:
1602  // useful to avoid the overhead of temporary buffering in _M_replace.
1603  basic_string&
1604  replace(iterator __i1, iterator __i2, _CharT* __k1, _CharT* __k2)
1605  {
1606  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1607  && __i2 <= _M_iend());
1608  __glibcxx_requires_valid_range(__k1, __k2);
1609  return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
1610  __k1, __k2 - __k1);
1611  }
1612 
1613  basic_string&
1614  replace(iterator __i1, iterator __i2,
1615  const _CharT* __k1, const _CharT* __k2)
1616  {
1617  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1618  && __i2 <= _M_iend());
1619  __glibcxx_requires_valid_range(__k1, __k2);
1620  return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
1621  __k1, __k2 - __k1);
1622  }
1623 
1624  basic_string&
1625  replace(iterator __i1, iterator __i2, iterator __k1, iterator __k2)
1626  {
1627  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1628  && __i2 <= _M_iend());
1629  __glibcxx_requires_valid_range(__k1, __k2);
1630  return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
1631  __k1.base(), __k2 - __k1);
1632  }
1633 
1634  basic_string&
1635  replace(iterator __i1, iterator __i2,
1636  const_iterator __k1, const_iterator __k2)
1637  {
1638  _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
1639  && __i2 <= _M_iend());
1640  __glibcxx_requires_valid_range(__k1, __k2);
1641  return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
1642  __k1.base(), __k2 - __k1);
1643  }
1644 
1645 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1646  /**
1647  * @brief Replace range of characters with initializer_list.
1648  * @param i1 Iterator referencing start of range to replace.
1649  * @param i2 Iterator referencing end of range to replace.
1650  * @param l The initializer_list of characters to insert.
1651  * @return Reference to this string.
1652  * @throw std::length_error If new length exceeds @c max_size().
1653  *
1654  * Removes the characters in the range [i1,i2). In place, characters
1655  * in the range [k1,k2) are inserted. If the length of result exceeds
1656  * max_size(), length_error is thrown. The value of the string doesn't
1657  * change if an error is thrown.
1658  */
1659  basic_string& replace(iterator __i1, iterator __i2,
1661  { return this->replace(__i1, __i2, __l.begin(), __l.end()); }
1662 #endif // __GXX_EXPERIMENTAL_CXX0X__
1663 
1664  private:
1665  template<class _Integer>
1666  basic_string&
1667  _M_replace_dispatch(iterator __i1, iterator __i2, _Integer __n,
1668  _Integer __val, __true_type)
1669  { return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __val); }
1670 
1671  template<class _InputIterator>
1672  basic_string&
1673  _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
1674  _InputIterator __k2, __false_type);
1675 
1676  basic_string&
1677  _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
1678  _CharT __c);
1679 
1680  basic_string&
1681  _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
1682  size_type __n2);
1683 
1684  // _S_construct_aux is used to implement the 21.3.1 para 15 which
1685  // requires special behaviour if _InIter is an integral type
1686  template<class _InIterator>
1687  static _CharT*
1688  _S_construct_aux(_InIterator __beg, _InIterator __end,
1689  const _Alloc& __a, __false_type)
1690  {
1691  typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
1692  return _S_construct(__beg, __end, __a, _Tag());
1693  }
1694 
1695  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1696  // 438. Ambiguity in the "do the right thing" clause
1697  template<class _Integer>
1698  static _CharT*
1699  _S_construct_aux(_Integer __beg, _Integer __end,
1700  const _Alloc& __a, __true_type)
1701  { return _S_construct_aux_2(static_cast<size_type>(__beg),
1702  __end, __a); }
1703 
1704  static _CharT*
1705  _S_construct_aux_2(size_type __req, _CharT __c, const _Alloc& __a)
1706  { return _S_construct(__req, __c, __a); }
1707 
1708  template<class _InIterator>
1709  static _CharT*
1710  _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a)
1711  {
1712  typedef typename std::__is_integer<_InIterator>::__type _Integral;
1713  return _S_construct_aux(__beg, __end, __a, _Integral());
1714  }
1715 
1716  // For Input Iterators, used in istreambuf_iterators, etc.
1717  template<class _InIterator>
1718  static _CharT*
1719  _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
1720  input_iterator_tag);
1721 
1722  // For forward_iterators up to random_access_iterators, used for
1723  // string::iterator, _CharT*, etc.
1724  template<class _FwdIterator>
1725  static _CharT*
1726  _S_construct(_FwdIterator __beg, _FwdIterator __end, const _Alloc& __a,
1727  forward_iterator_tag);
1728 
1729  static _CharT*
1730  _S_construct(size_type __req, _CharT __c, const _Alloc& __a);
1731 
1732  public:
1733 
1734  /**
1735  * @brief Copy substring into C string.
1736  * @param s C string to copy value into.
1737  * @param n Number of characters to copy.
1738  * @param pos Index of first character to copy.
1739  * @return Number of characters actually copied
1740  * @throw std::out_of_range If pos > size().
1741  *
1742  * Copies up to @a n characters starting at @a pos into the C string @a
1743  * s. If @a pos is %greater than size(), out_of_range is thrown.
1744  */
1745  size_type
1746  copy(_CharT* __s, size_type __n, size_type __pos = 0) const;
1747 
1748  /**
1749  * @brief Swap contents with another string.
1750  * @param s String to swap with.
1751  *
1752  * Exchanges the contents of this string with that of @a s in constant
1753  * time.
1754  */
1755  void
1756  swap(basic_string& __s);
1757 
1758  // String operations:
1759  /**
1760  * @brief Return const pointer to null-terminated contents.
1761  *
1762  * This is a handle to internal data. Do not modify or dire things may
1763  * happen.
1764  */
1765  const _CharT*
1766  c_str() const
1767  { return _M_data(); }
1768 
1769  /**
1770  * @brief Return const pointer to contents.
1771  *
1772  * This is a handle to internal data. Do not modify or dire things may
1773  * happen.
1774  */
1775  const _CharT*
1776  data() const
1777  { return _M_data(); }
1778 
1779  /**
1780  * @brief Return copy of allocator used to construct this string.
1781  */
1782  allocator_type
1784  { return _M_dataplus; }
1785 
1786  /**
1787  * @brief Find position of a C substring.
1788  * @param s C string to locate.
1789  * @param pos Index of character to search from.
1790  * @param n Number of characters from @a s to search for.
1791  * @return Index of start of first occurrence.
1792  *
1793  * Starting from @a pos, searches forward for the first @a n characters
1794  * in @a s within this string. If found, returns the index where it
1795  * begins. If not found, returns npos.
1796  */
1797  size_type
1798  find(const _CharT* __s, size_type __pos, size_type __n) const;
1799 
1800  /**
1801  * @brief Find position of a string.
1802  * @param str String to locate.
1803  * @param pos Index of character to search from (default 0).
1804  * @return Index of start of first occurrence.
1805  *
1806  * Starting from @a pos, searches forward for value of @a str within
1807  * this string. If found, returns the index where it begins. If not
1808  * found, returns npos.
1809  */
1810  size_type
1811  find(const basic_string& __str, size_type __pos = 0) const
1812  { return this->find(__str.data(), __pos, __str.size()); }
1813 
1814  /**
1815  * @brief Find position of a C string.
1816  * @param s C string to locate.
1817  * @param pos Index of character to search from (default 0).
1818  * @return Index of start of first occurrence.
1819  *
1820  * Starting from @a pos, searches forward for the value of @a s within
1821  * this string. If found, returns the index where it begins. If not
1822  * found, returns npos.
1823  */
1824  size_type
1825  find(const _CharT* __s, size_type __pos = 0) const
1826  {
1827  __glibcxx_requires_string(__s);
1828  return this->find(__s, __pos, traits_type::length(__s));
1829  }
1830 
1831  /**
1832  * @brief Find position of a character.
1833  * @param c Character to locate.
1834  * @param pos Index of character to search from (default 0).
1835  * @return Index of first occurrence.
1836  *
1837  * Starting from @a pos, searches forward for @a c within this string.
1838  * If found, returns the index where it was found. If not found,
1839  * returns npos.
1840  */
1841  size_type
1842  find(_CharT __c, size_type __pos = 0) const;
1843 
1844  /**
1845  * @brief Find last position of a string.
1846  * @param str String to locate.
1847  * @param pos Index of character to search back from (default end).
1848  * @return Index of start of last occurrence.
1849  *
1850  * Starting from @a pos, searches backward for value of @a str within
1851  * this string. If found, returns the index where it begins. If not
1852  * found, returns npos.
1853  */
1854  size_type
1855  rfind(const basic_string& __str, size_type __pos = npos) const
1856  { return this->rfind(__str.data(), __pos, __str.size()); }
1857 
1858  /**
1859  * @brief Find last position of a C substring.
1860  * @param s C string to locate.
1861  * @param pos Index of character to search back from.
1862  * @param n Number of characters from s to search for.
1863  * @return Index of start of last occurrence.
1864  *
1865  * Starting from @a pos, searches backward for the first @a n
1866  * characters in @a s within this string. If found, returns the index
1867  * where it begins. If not found, returns npos.
1868  */
1869  size_type
1870  rfind(const _CharT* __s, size_type __pos, size_type __n) const;
1871 
1872  /**
1873  * @brief Find last position of a C string.
1874  * @param s C string to locate.
1875  * @param pos Index of character to start search at (default end).
1876  * @return Index of start of last occurrence.
1877  *
1878  * Starting from @a pos, searches backward for the value of @a s within
1879  * this string. If found, returns the index where it begins. If not
1880  * found, returns npos.
1881  */
1882  size_type
1883  rfind(const _CharT* __s, size_type __pos = npos) const
1884  {
1885  __glibcxx_requires_string(__s);
1886  return this->rfind(__s, __pos, traits_type::length(__s));
1887  }
1888 
1889  /**
1890  * @brief Find last position of a character.
1891  * @param c Character to locate.
1892  * @param pos Index of character to search back from (default end).
1893  * @return Index of last occurrence.
1894  *
1895  * Starting from @a pos, searches backward for @a c within this string.
1896  * If found, returns the index where it was found. If not found,
1897  * returns npos.
1898  */
1899  size_type
1900  rfind(_CharT __c, size_type __pos = npos) const;
1901 
1902  /**
1903  * @brief Find position of a character of string.
1904  * @param str String containing characters to locate.
1905  * @param pos Index of character to search from (default 0).
1906  * @return Index of first occurrence.
1907  *
1908  * Starting from @a pos, searches forward for one of the characters of
1909  * @a str within this string. If found, returns the index where it was
1910  * found. If not found, returns npos.
1911  */
1912  size_type
1913  find_first_of(const basic_string& __str, size_type __pos = 0) const
1914  { return this->find_first_of(__str.data(), __pos, __str.size()); }
1915 
1916  /**
1917  * @brief Find position of a character of C substring.
1918  * @param s String containing characters to locate.
1919  * @param pos Index of character to search from.
1920  * @param n Number of characters from s to search for.
1921  * @return Index of first occurrence.
1922  *
1923  * Starting from @a pos, searches forward for one of the first @a n
1924  * characters of @a s within this string. If found, returns the index
1925  * where it was found. If not found, returns npos.
1926  */
1927  size_type
1928  find_first_of(const _CharT* __s, size_type __pos, size_type __n) const;
1929 
1930  /**
1931  * @brief Find position of a character of C string.
1932  * @param s String containing characters to locate.
1933  * @param pos Index of character to search from (default 0).
1934  * @return Index of first occurrence.
1935  *
1936  * Starting from @a pos, searches forward for one of the characters of
1937  * @a s within this string. If found, returns the index where it was
1938  * found. If not found, returns npos.
1939  */
1940  size_type
1941  find_first_of(const _CharT* __s, size_type __pos = 0) const
1942  {
1943  __glibcxx_requires_string(__s);
1944  return this->find_first_of(__s, __pos, traits_type::length(__s));
1945  }
1946 
1947  /**
1948  * @brief Find position of a character.
1949  * @param c Character to locate.
1950  * @param pos Index of character to search from (default 0).
1951  * @return Index of first occurrence.
1952  *
1953  * Starting from @a pos, searches forward for the character @a c within
1954  * this string. If found, returns the index where it was found. If
1955  * not found, returns npos.
1956  *
1957  * Note: equivalent to find(c, pos).
1958  */
1959  size_type
1960  find_first_of(_CharT __c, size_type __pos = 0) const
1961  { return this->find(__c, __pos); }
1962 
1963  /**
1964  * @brief Find last position of a character of string.
1965  * @param str String containing characters to locate.
1966  * @param pos Index of character to search back from (default end).
1967  * @return Index of last occurrence.
1968  *
1969  * Starting from @a pos, searches backward for one of the characters of
1970  * @a str within this string. If found, returns the index where it was
1971  * found. If not found, returns npos.
1972  */
1973  size_type
1974  find_last_of(const basic_string& __str, size_type __pos = npos) const
1975  { return this->find_last_of(__str.data(), __pos, __str.size()); }
1976 
1977  /**
1978  * @brief Find last position of a character of C substring.
1979  * @param s C string containing characters to locate.
1980  * @param pos Index of character to search back from.
1981  * @param n Number of characters from s to search for.
1982  * @return Index of last occurrence.
1983  *
1984  * Starting from @a pos, searches backward for one of the first @a n
1985  * characters of @a s within this string. If found, returns the index
1986  * where it was found. If not found, returns npos.
1987  */
1988  size_type
1989  find_last_of(const _CharT* __s, size_type __pos, size_type __n) const;
1990 
1991  /**
1992  * @brief Find last position of a character of C string.
1993  * @param s C string containing characters to locate.
1994  * @param pos Index of character to search back from (default end).
1995  * @return Index of last occurrence.
1996  *
1997  * Starting from @a pos, searches backward for one of the characters of
1998  * @a s within this string. If found, returns the index where it was
1999  * found. If not found, returns npos.
2000  */
2001  size_type
2002  find_last_of(const _CharT* __s, size_type __pos = npos) const
2003  {
2004  __glibcxx_requires_string(__s);
2005  return this->find_last_of(__s, __pos, traits_type::length(__s));
2006  }
2007 
2008  /**
2009  * @brief Find last position of a character.
2010  * @param c Character to locate.
2011  * @param pos Index of character to search back from (default end).
2012  * @return Index of last occurrence.
2013  *
2014  * Starting from @a pos, searches backward for @a c within this string.
2015  * If found, returns the index where it was found. If not found,
2016  * returns npos.
2017  *
2018  * Note: equivalent to rfind(c, pos).
2019  */
2020  size_type
2021  find_last_of(_CharT __c, size_type __pos = npos) const
2022  { return this->rfind(__c, __pos); }
2023 
2024  /**
2025  * @brief Find position of a character not in string.
2026  * @param str String containing characters to avoid.
2027  * @param pos Index of character to search from (default 0).
2028  * @return Index of first occurrence.
2029  *
2030  * Starting from @a pos, searches forward for a character not contained
2031  * in @a str within this string. If found, returns the index where it
2032  * was found. If not found, returns npos.
2033  */
2034  size_type
2035  find_first_not_of(const basic_string& __str, size_type __pos = 0) const
2036  { return this->find_first_not_of(__str.data(), __pos, __str.size()); }
2037 
2038  /**
2039  * @brief Find position of a character not in C substring.
2040  * @param s C string containing characters to avoid.
2041  * @param pos Index of character to search from.
2042  * @param n Number of characters from s to consider.
2043  * @return Index of first occurrence.
2044  *
2045  * Starting from @a pos, searches forward for a character not contained
2046  * in the first @a n characters of @a s within this string. If found,
2047  * returns the index where it was found. If not found, returns npos.
2048  */
2049  size_type
2050  find_first_not_of(const _CharT* __s, size_type __pos,
2051  size_type __n) const;
2052 
2053  /**
2054  * @brief Find position of a character not in C string.
2055  * @param s C string containing characters to avoid.
2056  * @param pos Index of character to search from (default 0).
2057  * @return Index of first occurrence.
2058  *
2059  * Starting from @a pos, searches forward for a character not contained
2060  * in @a s within this string. If found, returns the index where it
2061  * was found. If not found, returns npos.
2062  */
2063  size_type
2064  find_first_not_of(const _CharT* __s, size_type __pos = 0) const
2065  {
2066  __glibcxx_requires_string(__s);
2067  return this->find_first_not_of(__s, __pos, traits_type::length(__s));
2068  }
2069 
2070  /**
2071  * @brief Find position of a different character.
2072  * @param c Character to avoid.
2073  * @param pos Index of character to search from (default 0).
2074  * @return Index of first occurrence.
2075  *
2076  * Starting from @a pos, searches forward for a character other than @a c
2077  * within this string. If found, returns the index where it was found.
2078  * If not found, returns npos.
2079  */
2080  size_type
2081  find_first_not_of(_CharT __c, size_type __pos = 0) const;
2082 
2083  /**
2084  * @brief Find last position of a character not in string.
2085  * @param str String containing characters to avoid.
2086  * @param pos Index of character to search back from (default end).
2087  * @return Index of last occurrence.
2088  *
2089  * Starting from @a pos, searches backward for a character not
2090  * contained in @a str within this string. If found, returns the index
2091  * where it was found. If not found, returns npos.
2092  */
2093  size_type
2094  find_last_not_of(const basic_string& __str, size_type __pos = npos) const
2095  { return this->find_last_not_of(__str.data(), __pos, __str.size()); }
2096 
2097  /**
2098  * @brief Find last position of a character not in C substring.
2099  * @param s C string containing characters to avoid.
2100  * @param pos Index of character to search back from.
2101  * @param n Number of characters from s to consider.
2102  * @return Index of last occurrence.
2103  *
2104  * Starting from @a pos, searches backward for a character not
2105  * contained in the first @a n characters of @a s within this string.
2106  * If found, returns the index where it was found. If not found,
2107  * returns npos.
2108  */
2109  size_type
2110  find_last_not_of(const _CharT* __s, size_type __pos,
2111  size_type __n) const;
2112  /**
2113  * @brief Find last position of a character not in C string.
2114  * @param s C string containing characters to avoid.
2115  * @param pos Index of character to search back from (default end).
2116  * @return Index of last occurrence.
2117  *
2118  * Starting from @a pos, searches backward for a character not
2119  * contained in @a s within this string. If found, returns the index
2120  * where it was found. If not found, returns npos.
2121  */
2122  size_type
2123  find_last_not_of(const _CharT* __s, size_type __pos = npos) const
2124  {
2125  __glibcxx_requires_string(__s);
2126  return this->find_last_not_of(__s, __pos, traits_type::length(__s));
2127  }
2128 
2129  /**
2130  * @brief Find last position of a different character.
2131  * @param c Character to avoid.
2132  * @param pos Index of character to search back from (default end).
2133  * @return Index of last occurrence.
2134  *
2135  * Starting from @a pos, searches backward for a character other than
2136  * @a c within this string. If found, returns the index where it was
2137  * found. If not found, returns npos.
2138  */
2139  size_type
2140  find_last_not_of(_CharT __c, size_type __pos = npos) const;
2141 
2142  /**
2143  * @brief Get a substring.
2144  * @param pos Index of first character (default 0).
2145  * @param n Number of characters in substring (default remainder).
2146  * @return The new string.
2147  * @throw std::out_of_range If pos > size().
2148  *
2149  * Construct and return a new string using the @a n characters starting
2150  * at @a pos. If the string is too short, use the remainder of the
2151  * characters. If @a pos is beyond the end of the string, out_of_range
2152  * is thrown.
2153  */
2154  basic_string
2155  substr(size_type __pos = 0, size_type __n = npos) const
2156  { return basic_string(*this,
2157  _M_check(__pos, "basic_string::substr"), __n); }
2158 
2159  /**
2160  * @brief Compare to a string.
2161  * @param str String to compare against.
2162  * @return Integer < 0, 0, or > 0.
2163  *
2164  * Returns an integer < 0 if this string is ordered before @a str, 0 if
2165  * their values are equivalent, or > 0 if this string is ordered after
2166  * @a str. Determines the effective length rlen of the strings to
2167  * compare as the smallest of size() and str.size(). The function
2168  * then compares the two strings by calling traits::compare(data(),
2169  * str.data(),rlen). If the result of the comparison is nonzero returns
2170  * it, otherwise the shorter one is ordered first.
2171  */
2172  int
2173  compare(const basic_string& __str) const
2174  {
2175  const size_type __size = this->size();
2176  const size_type __osize = __str.size();
2177  const size_type __len = std::min(__size, __osize);
2178 
2179  int __r = traits_type::compare(_M_data(), __str.data(), __len);
2180  if (!__r)
2181  __r = _S_compare(__size, __osize);
2182  return __r;
2183  }
2184 
2185  /**
2186  * @brief Compare substring to a string.
2187  * @param pos Index of first character of substring.
2188  * @param n Number of characters in substring.
2189  * @param str String to compare against.
2190  * @return Integer < 0, 0, or > 0.
2191  *
2192  * Form the substring of this string from the @a n characters starting
2193  * at @a pos. Returns an integer < 0 if the substring is ordered
2194  * before @a str, 0 if their values are equivalent, or > 0 if the
2195  * substring is ordered after @a str. Determines the effective length
2196  * rlen of the strings to compare as the smallest of the length of the
2197  * substring and @a str.size(). The function then compares the two
2198  * strings by calling traits::compare(substring.data(),str.data(),rlen).
2199  * If the result of the comparison is nonzero returns it, otherwise the
2200  * shorter one is ordered first.
2201  */
2202  int
2203  compare(size_type __pos, size_type __n, const basic_string& __str) const;
2204 
2205  /**
2206  * @brief Compare substring to a substring.
2207  * @param pos1 Index of first character of substring.
2208  * @param n1 Number of characters in substring.
2209  * @param str String to compare against.
2210  * @param pos2 Index of first character of substring of str.
2211  * @param n2 Number of characters in substring of str.
2212  * @return Integer < 0, 0, or > 0.
2213  *
2214  * Form the substring of this string from the @a n1 characters starting
2215  * at @a pos1. Form the substring of @a str from the @a n2 characters
2216  * starting at @a pos2. Returns an integer < 0 if this substring is
2217  * ordered before the substring of @a str, 0 if their values are
2218  * equivalent, or > 0 if this substring is ordered after the substring
2219  * of @a str. Determines the effective length rlen of the strings
2220  * to compare as the smallest of the lengths of the substrings. The
2221  * function then compares the two strings by calling
2222  * traits::compare(substring.data(),str.substr(pos2,n2).data(),rlen).
2223  * If the result of the comparison is nonzero returns it, otherwise the
2224  * shorter one is ordered first.
2225  */
2226  int
2227  compare(size_type __pos1, size_type __n1, const basic_string& __str,
2228  size_type __pos2, size_type __n2) const;
2229 
2230  /**
2231  * @brief Compare to a C string.
2232  * @param s C string to compare against.
2233  * @return Integer < 0, 0, or > 0.
2234  *
2235  * Returns an integer < 0 if this string is ordered before @a s, 0 if
2236  * their values are equivalent, or > 0 if this string is ordered after
2237  * @a s. Determines the effective length rlen of the strings to
2238  * compare as the smallest of size() and the length of a string
2239  * constructed from @a s. The function then compares the two strings
2240  * by calling traits::compare(data(),s,rlen). If the result of the
2241  * comparison is nonzero returns it, otherwise the shorter one is
2242  * ordered first.
2243  */
2244  int
2245  compare(const _CharT* __s) const;
2246 
2247  // _GLIBCXX_RESOLVE_LIB_DEFECTS
2248  // 5 String::compare specification questionable
2249  /**
2250  * @brief Compare substring to a C string.
2251  * @param pos Index of first character of substring.
2252  * @param n1 Number of characters in substring.
2253  * @param s C string to compare against.
2254  * @return Integer < 0, 0, or > 0.
2255  *
2256  * Form the substring of this string from the @a n1 characters starting
2257  * at @a pos. Returns an integer < 0 if the substring is ordered
2258  * before @a s, 0 if their values are equivalent, or > 0 if the
2259  * substring is ordered after @a s. Determines the effective length
2260  * rlen of the strings to compare as the smallest of the length of the
2261  * substring and the length of a string constructed from @a s. The
2262  * function then compares the two string by calling
2263  * traits::compare(substring.data(),s,rlen). If the result of the
2264  * comparison is nonzero returns it, otherwise the shorter one is
2265  * ordered first.
2266  */
2267  int
2268  compare(size_type __pos, size_type __n1, const _CharT* __s) const;
2269 
2270  /**
2271  * @brief Compare substring against a character %array.
2272  * @param pos1 Index of first character of substring.
2273  * @param n1 Number of characters in substring.
2274  * @param s character %array to compare against.
2275  * @param n2 Number of characters of s.
2276  * @return Integer < 0, 0, or > 0.
2277  *
2278  * Form the substring of this string from the @a n1 characters starting
2279  * at @a pos1. Form a string from the first @a n2 characters of @a s.
2280  * Returns an integer < 0 if this substring is ordered before the string
2281  * from @a s, 0 if their values are equivalent, or > 0 if this substring
2282  * is ordered after the string from @a s. Determines the effective
2283  * length rlen of the strings to compare as the smallest of the length
2284  * of the substring and @a n2. The function then compares the two
2285  * strings by calling traits::compare(substring.data(),s,rlen). If the
2286  * result of the comparison is nonzero returns it, otherwise the shorter
2287  * one is ordered first.
2288  *
2289  * NB: s must have at least n2 characters, &apos;\\0&apos; has
2290  * no special meaning.
2291  */
2292  int
2293  compare(size_type __pos, size_type __n1, const _CharT* __s,
2294  size_type __n2) const;
2295  };
2296 
2297  // operator+
2298  /**
2299  * @brief Concatenate two strings.
2300  * @param lhs First string.
2301  * @param rhs Last string.
2302  * @return New string with value of @a lhs followed by @a rhs.
2303  */
2304  template<typename _CharT, typename _Traits, typename _Alloc>
2305  basic_string<_CharT, _Traits, _Alloc>
2308  {
2310  __str.append(__rhs);
2311  return __str;
2312  }
2313 
2314  /**
2315  * @brief Concatenate C string and string.
2316  * @param lhs First string.
2317  * @param rhs Last string.
2318  * @return New string with value of @a lhs followed by @a rhs.
2319  */
2320  template<typename _CharT, typename _Traits, typename _Alloc>
2321  basic_string<_CharT,_Traits,_Alloc>
2322  operator+(const _CharT* __lhs,
2323  const basic_string<_CharT,_Traits,_Alloc>& __rhs);
2324 
2325  /**
2326  * @brief Concatenate character and string.
2327  * @param lhs First string.
2328  * @param rhs Last string.
2329  * @return New string with @a lhs followed by @a rhs.
2330  */
2331  template<typename _CharT, typename _Traits, typename _Alloc>
2332  basic_string<_CharT,_Traits,_Alloc>
2333  operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Alloc>& __rhs);
2334 
2335  /**
2336  * @brief Concatenate string and C string.
2337  * @param lhs First string.
2338  * @param rhs Last string.
2339  * @return New string with @a lhs followed by @a rhs.
2340  */
2341  template<typename _CharT, typename _Traits, typename _Alloc>
2342  inline basic_string<_CharT, _Traits, _Alloc>
2344  const _CharT* __rhs)
2345  {
2347  __str.append(__rhs);
2348  return __str;
2349  }
2350 
2351  /**
2352  * @brief Concatenate string and character.
2353  * @param lhs First string.
2354  * @param rhs Last string.
2355  * @return New string with @a lhs followed by @a rhs.
2356  */
2357  template<typename _CharT, typename _Traits, typename _Alloc>
2358  inline basic_string<_CharT, _Traits, _Alloc>
2360  {
2361  typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
2362  typedef typename __string_type::size_type __size_type;
2363  __string_type __str(__lhs);
2364  __str.append(__size_type(1), __rhs);
2365  return __str;
2366  }
2367 
2368 #ifdef __GXX_EXPERIMENTAL_CXX0X__
2369  template<typename _CharT, typename _Traits, typename _Alloc>
2370  inline basic_string<_CharT, _Traits, _Alloc>
2371  operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
2372  const basic_string<_CharT, _Traits, _Alloc>& __rhs)
2373  { return std::move(__lhs.append(__rhs)); }
2374 
2375  template<typename _CharT, typename _Traits, typename _Alloc>
2376  inline basic_string<_CharT, _Traits, _Alloc>
2377  operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2378  basic_string<_CharT, _Traits, _Alloc>&& __rhs)
2379  { return std::move(__rhs.insert(0, __lhs)); }
2380 
2381  template<typename _CharT, typename _Traits, typename _Alloc>
2382  inline basic_string<_CharT, _Traits, _Alloc>
2383  operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
2384  basic_string<_CharT, _Traits, _Alloc>&& __rhs)
2385  {
2386  const auto __size = __lhs.size() + __rhs.size();
2387  const bool __cond = (__size > __lhs.capacity()
2388  && __size <= __rhs.capacity());
2389  return __cond ? std::move(__rhs.insert(0, __lhs))
2390  : std::move(__lhs.append(__rhs));
2391  }
2392 
2393  template<typename _CharT, typename _Traits, typename _Alloc>
2394  inline basic_string<_CharT, _Traits, _Alloc>
2395  operator+(const _CharT* __lhs,
2396  basic_string<_CharT, _Traits, _Alloc>&& __rhs)
2397  { return std::move(__rhs.insert(0, __lhs)); }
2398 
2399  template<typename _CharT, typename _Traits, typename _Alloc>
2400  inline basic_string<_CharT, _Traits, _Alloc>
2401  operator+(_CharT __lhs,
2402  basic_string<_CharT, _Traits, _Alloc>&& __rhs)
2403  { return std::move(__rhs.insert(0, 1, __lhs)); }
2404 
2405  template<typename _CharT, typename _Traits, typename _Alloc>
2406  inline basic_string<_CharT, _Traits, _Alloc>
2407  operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
2408  const _CharT* __rhs)
2409  { return std::move(__lhs.append(__rhs)); }
2410 
2411  template<typename _CharT, typename _Traits, typename _Alloc>
2412  inline basic_string<_CharT, _Traits, _Alloc>
2413  operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
2414  _CharT __rhs)
2415  { return std::move(__lhs.append(1, __rhs)); }
2416 #endif
2417 
2418  // operator ==
2419  /**
2420  * @brief Test equivalence of two strings.
2421  * @param lhs First string.
2422  * @param rhs Second string.
2423  * @return True if @a lhs.compare(@a rhs) == 0. False otherwise.
2424  */
2425  template<typename _CharT, typename _Traits, typename _Alloc>
2426  inline bool
2427  operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2429  { return __lhs.compare(__rhs) == 0; }
2430 
2431  template<typename _CharT>
2432  inline
2433  typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, bool>::__type
2434  operator==(const basic_string<_CharT>& __lhs,
2435  const basic_string<_CharT>& __rhs)
2436  { return (__lhs.size() == __rhs.size()
2437  && !std::char_traits<_CharT>::compare(__lhs.data(), __rhs.data(),
2438  __lhs.size())); }
2439 
2440  /**
2441  * @brief Test equivalence of C string and string.
2442  * @param lhs C string.
2443  * @param rhs String.
2444  * @return True if @a rhs.compare(@a lhs) == 0. False otherwise.
2445  */
2446  template<typename _CharT, typename _Traits, typename _Alloc>
2447  inline bool
2448  operator==(const _CharT* __lhs,
2450  { return __rhs.compare(__lhs) == 0; }
2451 
2452  /**
2453  * @brief Test equivalence of string and C string.
2454  * @param lhs String.
2455  * @param rhs C string.
2456  * @return True if @a lhs.compare(@a rhs) == 0. False otherwise.
2457  */
2458  template<typename _CharT, typename _Traits, typename _Alloc>
2459  inline bool
2460  operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2461  const _CharT* __rhs)
2462  { return __lhs.compare(__rhs) == 0; }
2463 
2464  // operator !=
2465  /**
2466  * @brief Test difference of two strings.
2467  * @param lhs First string.
2468  * @param rhs Second string.
2469  * @return True if @a lhs.compare(@a rhs) != 0. False otherwise.
2470  */
2471  template<typename _CharT, typename _Traits, typename _Alloc>
2472  inline bool
2473  operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2475  { return !(__lhs == __rhs); }
2476 
2477  /**
2478  * @brief Test difference of C string and string.
2479  * @param lhs C string.
2480  * @param rhs String.
2481  * @return True if @a rhs.compare(@a lhs) != 0. False otherwise.
2482  */
2483  template<typename _CharT, typename _Traits, typename _Alloc>
2484  inline bool
2485  operator!=(const _CharT* __lhs,
2487  { return !(__lhs == __rhs); }
2488 
2489  /**
2490  * @brief Test difference of string and C string.
2491  * @param lhs String.
2492  * @param rhs C string.
2493  * @return True if @a lhs.compare(@a rhs) != 0. False otherwise.
2494  */
2495  template<typename _CharT, typename _Traits, typename _Alloc>
2496  inline bool
2497  operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2498  const _CharT* __rhs)
2499  { return !(__lhs == __rhs); }
2500 
2501  // operator <
2502  /**
2503  * @brief Test if string precedes string.
2504  * @param lhs First string.
2505  * @param rhs Second string.
2506  * @return True if @a lhs precedes @a rhs. False otherwise.
2507  */
2508  template<typename _CharT, typename _Traits, typename _Alloc>
2509  inline bool
2510  operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2512  { return __lhs.compare(__rhs) < 0; }
2513 
2514  /**
2515  * @brief Test if string precedes C string.
2516  * @param lhs String.
2517  * @param rhs C string.
2518  * @return True if @a lhs precedes @a rhs. False otherwise.
2519  */
2520  template<typename _CharT, typename _Traits, typename _Alloc>
2521  inline bool
2522  operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2523  const _CharT* __rhs)
2524  { return __lhs.compare(__rhs) < 0; }
2525 
2526  /**
2527  * @brief Test if C string precedes string.
2528  * @param lhs C string.
2529  * @param rhs String.
2530  * @return True if @a lhs precedes @a rhs. False otherwise.
2531  */
2532  template<typename _CharT, typename _Traits, typename _Alloc>
2533  inline bool
2534  operator<(const _CharT* __lhs,
2536  { return __rhs.compare(__lhs) > 0; }
2537 
2538  // operator >
2539  /**
2540  * @brief Test if string follows string.
2541  * @param lhs First string.
2542  * @param rhs Second string.
2543  * @return True if @a lhs follows @a rhs. False otherwise.
2544  */
2545  template<typename _CharT, typename _Traits, typename _Alloc>
2546  inline bool
2549  { return __lhs.compare(__rhs) > 0; }
2550 
2551  /**
2552  * @brief Test if string follows C string.
2553  * @param lhs String.
2554  * @param rhs C string.
2555  * @return True if @a lhs follows @a rhs. False otherwise.
2556  */
2557  template<typename _CharT, typename _Traits, typename _Alloc>
2558  inline bool
2560  const _CharT* __rhs)
2561  { return __lhs.compare(__rhs) > 0; }
2562 
2563  /**
2564  * @brief Test if C string follows string.
2565  * @param lhs C string.
2566  * @param rhs String.
2567  * @return True if @a lhs follows @a rhs. False otherwise.
2568  */
2569  template<typename _CharT, typename _Traits, typename _Alloc>
2570  inline bool
2571  operator>(const _CharT* __lhs,
2573  { return __rhs.compare(__lhs) < 0; }
2574 
2575  // operator <=
2576  /**
2577  * @brief Test if string doesn't follow string.
2578  * @param lhs First string.
2579  * @param rhs Second string.
2580  * @return True if @a lhs doesn't follow @a rhs. False otherwise.
2581  */
2582  template<typename _CharT, typename _Traits, typename _Alloc>
2583  inline bool
2584  operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2586  { return __lhs.compare(__rhs) <= 0; }
2587 
2588  /**
2589  * @brief Test if string doesn't follow C string.
2590  * @param lhs String.
2591  * @param rhs C string.
2592  * @return True if @a lhs doesn't follow @a rhs. False otherwise.
2593  */
2594  template<typename _CharT, typename _Traits, typename _Alloc>
2595  inline bool
2596  operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2597  const _CharT* __rhs)
2598  { return __lhs.compare(__rhs) <= 0; }
2599 
2600  /**
2601  * @brief Test if C string doesn't follow string.
2602  * @param lhs C string.
2603  * @param rhs String.
2604  * @return True if @a lhs doesn't follow @a rhs. False otherwise.
2605  */
2606  template<typename _CharT, typename _Traits, typename _Alloc>
2607  inline bool
2608  operator<=(const _CharT* __lhs,
2610  { return __rhs.compare(__lhs) >= 0; }
2611 
2612  // operator >=
2613  /**
2614  * @brief Test if string doesn't precede string.
2615  * @param lhs First string.
2616  * @param rhs Second string.
2617  * @return True if @a lhs doesn't precede @a rhs. False otherwise.
2618  */
2619  template<typename _CharT, typename _Traits, typename _Alloc>
2620  inline bool
2621  operator>=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2623  { return __lhs.compare(__rhs) >= 0; }
2624 
2625  /**
2626  * @brief Test if string doesn't precede C string.
2627  * @param lhs String.
2628  * @param rhs C string.
2629  * @return True if @a lhs doesn't precede @a rhs. False otherwise.
2630  */
2631  template<typename _CharT, typename _Traits, typename _Alloc>
2632  inline bool
2633  operator>=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
2634  const _CharT* __rhs)
2635  { return __lhs.compare(__rhs) >= 0; }
2636 
2637  /**
2638  * @brief Test if C string doesn't precede string.
2639  * @param lhs C string.
2640  * @param rhs String.
2641  * @return True if @a lhs doesn't precede @a rhs. False otherwise.
2642  */
2643  template<typename _CharT, typename _Traits, typename _Alloc>
2644  inline bool
2645  operator>=(const _CharT* __lhs,
2647  { return __rhs.compare(__lhs) <= 0; }
2648 
2649  /**
2650  * @brief Swap contents of two strings.
2651  * @param lhs First string.
2652  * @param rhs Second string.
2653  *
2654  * Exchanges the contents of @a lhs and @a rhs in constant time.
2655  */
2656  template<typename _CharT, typename _Traits, typename _Alloc>
2657  inline void
2660  { __lhs.swap(__rhs); }
2661 
2662  /**
2663  * @brief Read stream into a string.
2664  * @param is Input stream.
2665  * @param str Buffer to store into.
2666  * @return Reference to the input stream.
2667  *
2668  * Stores characters from @a is into @a str until whitespace is found, the
2669  * end of the stream is encountered, or str.max_size() is reached. If
2670  * is.width() is non-zero, that is the limit on the number of characters
2671  * stored into @a str. Any previous contents of @a str are erased.
2672  */
2673  template<typename _CharT, typename _Traits, typename _Alloc>
2674  basic_istream<_CharT, _Traits>&
2675  operator>>(basic_istream<_CharT, _Traits>& __is,
2676  basic_string<_CharT, _Traits, _Alloc>& __str);
2677 
2678  template<>
2679  basic_istream<char>&
2680  operator>>(basic_istream<char>& __is, basic_string<char>& __str);
2681 
2682  /**
2683  * @brief Write string to a stream.
2684  * @param os Output stream.
2685  * @param str String to write out.
2686  * @return Reference to the output stream.
2687  *
2688  * Output characters of @a str into os following the same rules as for
2689  * writing a C string.
2690  */
2691  template<typename _CharT, typename _Traits, typename _Alloc>
2692  inline basic_ostream<_CharT, _Traits>&
2693  operator<<(basic_ostream<_CharT, _Traits>& __os,
2695  {
2696  // _GLIBCXX_RESOLVE_LIB_DEFECTS
2697  // 586. string inserter not a formatted function
2698  return __ostream_insert(__os, __str.data(), __str.size());
2699  }
2700 
2701  /**
2702  * @brief Read a line from stream into a string.
2703  * @param is Input stream.
2704  * @param str Buffer to store into.
2705  * @param delim Character marking end of line.
2706  * @return Reference to the input stream.
2707  *
2708  * Stores characters from @a is into @a str until @a delim is found, the
2709  * end of the stream is encountered, or str.max_size() is reached. If
2710  * is.width() is non-zero, that is the limit on the number of characters
2711  * stored into @a str. Any previous contents of @a str are erased. If @a
2712  * delim was encountered, it is extracted but not stored into @a str.
2713  */
2714  template<typename _CharT, typename _Traits, typename _Alloc>
2715  basic_istream<_CharT, _Traits>&
2716  getline(basic_istream<_CharT, _Traits>& __is,
2717  basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim);
2718 
2719  /**
2720  * @brief Read a line from stream into a string.
2721  * @param is Input stream.
2722  * @param str Buffer to store into.
2723  * @return Reference to the input stream.
2724  *
2725  * Stores characters from is into @a str until &apos;\n&apos; is
2726  * found, the end of the stream is encountered, or str.max_size()
2727  * is reached. If is.width() is non-zero, that is the limit on the
2728  * number of characters stored into @a str. Any previous contents
2729  * of @a str are erased. If end of line was encountered, it is
2730  * extracted but not stored into @a str.
2731  */
2732  template<typename _CharT, typename _Traits, typename _Alloc>
2733  inline basic_istream<_CharT, _Traits>&
2736  { return getline(__is, __str, __is.widen('\n')); }
2737 
2738  template<>
2739  basic_istream<char>&
2740  getline(basic_istream<char>& __in, basic_string<char>& __str,
2741  char __delim);
2742 
2743 #ifdef _GLIBCXX_USE_WCHAR_T
2744  template<>
2745  basic_istream<wchar_t>&
2746  getline(basic_istream<wchar_t>& __in, basic_string<wchar_t>& __str,
2747  wchar_t __delim);
2748 #endif
2749 
2750 _GLIBCXX_END_NAMESPACE_VERSION
2751 } // namespace
2752 
2753 #if (defined(__GXX_EXPERIMENTAL_CXX0X__) && defined(_GLIBCXX_USE_C99) \
2754  && !defined(_GLIBCXX_HAVE_BROKEN_VSWPRINTF))
2755 
2756 #include <ext/string_conversions.h>
2757 
2758 namespace std _GLIBCXX_VISIBILITY(default)
2759 {
2760 _GLIBCXX_BEGIN_NAMESPACE_VERSION
2761 
2762  // 21.4 Numeric Conversions [string.conversions].
2763  inline int
2764  stoi(const string& __str, size_t* __idx = 0, int __base = 10)
2765  { return __gnu_cxx::__stoa<long, int>(&std::strtol, "stoi", __str.c_str(),
2766  __idx, __base); }
2767 
2768  inline long
2769  stol(const string& __str, size_t* __idx = 0, int __base = 10)
2770  { return __gnu_cxx::__stoa(&std::strtol, "stol", __str.c_str(),
2771  __idx, __base); }
2772 
2773  inline unsigned long
2774  stoul(const string& __str, size_t* __idx = 0, int __base = 10)
2775  { return __gnu_cxx::__stoa(&std::strtoul, "stoul", __str.c_str(),
2776  __idx, __base); }
2777 
2778  inline long long
2779  stoll(const string& __str, size_t* __idx = 0, int __base = 10)
2780  { return __gnu_cxx::__stoa(&std::strtoll, "stoll", __str.c_str(),
2781  __idx, __base); }
2782 
2783  inline unsigned long long
2784  stoull(const string& __str, size_t* __idx = 0, int __base = 10)
2785  { return __gnu_cxx::__stoa(&std::strtoull, "stoull", __str.c_str(),
2786  __idx, __base); }
2787 
2788  // NB: strtof vs strtod.
2789  inline float
2790  stof(const string& __str, size_t* __idx = 0)
2791  { return __gnu_cxx::__stoa(&std::strtof, "stof", __str.c_str(), __idx); }
2792 
2793  inline double
2794  stod(const string& __str, size_t* __idx = 0)
2795  { return __gnu_cxx::__stoa(&std::strtod, "stod", __str.c_str(), __idx); }
2796 
2797  inline long double
2798  stold(const string& __str, size_t* __idx = 0)
2799  { return __gnu_cxx::__stoa(&std::strtold, "stold", __str.c_str(), __idx); }
2800 
2801  // NB: (v)snprintf vs sprintf.
2802 
2803  // DR 1261.
2804  inline string
2805  to_string(int __val)
2806  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, 4 * sizeof(int),
2807  "%d", __val); }
2808 
2809  inline string
2810  to_string(unsigned __val)
2811  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf,
2812  4 * sizeof(unsigned),
2813  "%u", __val); }
2814 
2815  inline string
2816  to_string(long __val)
2817  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, 4 * sizeof(long),
2818  "%ld", __val); }
2819 
2820  inline string
2821  to_string(unsigned long __val)
2822  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf,
2823  4 * sizeof(unsigned long),
2824  "%lu", __val); }
2825 
2826  inline string
2827  to_string(long long __val)
2828  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf,
2829  4 * sizeof(long long),
2830  "%lld", __val); }
2831 
2832  inline string
2833  to_string(unsigned long long __val)
2834  { return __gnu_cxx::__to_xstring<string>(&std::vsnprintf,
2835  4 * sizeof(unsigned long long),
2836  "%llu", __val); }
2837 
2838  inline string
2839  to_string(float __val)
2840  {
2841  const int __n =
2842  __gnu_cxx::__numeric_traits<float>::__max_exponent10 + 20;
2843  return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
2844  "%f", __val);
2845  }
2846 
2847  inline string
2848  to_string(double __val)
2849  {
2850  const int __n =
2851  __gnu_cxx::__numeric_traits<double>::__max_exponent10 + 20;
2852  return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
2853  "%f", __val);
2854  }
2855 
2856  inline string
2857  to_string(long double __val)
2858  {
2859  const int __n =
2860  __gnu_cxx::__numeric_traits<long double>::__max_exponent10 + 20;
2861  return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
2862  "%Lf", __val);
2863  }
2864 
2865 #ifdef _GLIBCXX_USE_WCHAR_T
2866  inline int
2867  stoi(const wstring& __str, size_t* __idx = 0, int __base = 10)
2868  { return __gnu_cxx::__stoa<long, int>(&std::wcstol, "stoi", __str.c_str(),
2869  __idx, __base); }
2870 
2871  inline long
2872  stol(const wstring& __str, size_t* __idx = 0, int __base = 10)
2873  { return __gnu_cxx::__stoa(&std::wcstol, "stol", __str.c_str(),
2874  __idx, __base); }
2875 
2876  inline unsigned long
2877  stoul(const wstring& __str, size_t* __idx = 0, int __base = 10)
2878  { return __gnu_cxx::__stoa(&std::wcstoul, "stoul", __str.c_str(),
2879  __idx, __base); }
2880 
2881  inline long long
2882  stoll(const wstring& __str, size_t* __idx = 0, int __base = 10)
2883  { return __gnu_cxx::__stoa(&std::wcstoll, "stoll", __str.c_str(),
2884  __idx, __base); }
2885 
2886  inline unsigned long long
2887  stoull(const wstring& __str, size_t* __idx = 0, int __base = 10)
2888  { return __gnu_cxx::__stoa(&std::wcstoull, "stoull", __str.c_str(),
2889  __idx, __base); }
2890 
2891  // NB: wcstof vs wcstod.
2892  inline float
2893  stof(const wstring& __str, size_t* __idx = 0)
2894  { return __gnu_cxx::__stoa(&std::wcstof, "stof", __str.c_str(), __idx); }
2895 
2896  inline double
2897  stod(const wstring& __str, size_t* __idx = 0)
2898  { return __gnu_cxx::__stoa(&std::wcstod, "stod", __str.c_str(), __idx); }
2899 
2900  inline long double
2901  stold(const wstring& __str, size_t* __idx = 0)
2902  { return __gnu_cxx::__stoa(&std::wcstold, "stold", __str.c_str(), __idx); }
2903 
2904  // DR 1261.
2905  inline wstring
2906  to_wstring(int __val)
2907  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, 4 * sizeof(int),
2908  L"%d", __val); }
2909 
2910  inline wstring
2911  to_wstring(unsigned __val)
2912  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
2913  4 * sizeof(unsigned),
2914  L"%u", __val); }
2915 
2916  inline wstring
2917  to_wstring(long __val)
2918  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, 4 * sizeof(long),
2919  L"%ld", __val); }
2920 
2921  inline wstring
2922  to_wstring(unsigned long __val)
2923  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
2924  4 * sizeof(unsigned long),
2925  L"%lu", __val); }
2926 
2927  inline wstring
2928  to_wstring(long long __val)
2929  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
2930  4 * sizeof(long long),
2931  L"%lld", __val); }
2932 
2933  inline wstring
2934  to_wstring(unsigned long long __val)
2935  { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
2936  4 * sizeof(unsigned long long),
2937  L"%llu", __val); }
2938 
2939  inline wstring
2940  to_wstring(float __val)
2941  {
2942  const int __n =
2943  __gnu_cxx::__numeric_traits<float>::__max_exponent10 + 20;
2944  return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
2945  L"%f", __val);
2946  }
2947 
2948  inline wstring
2949  to_wstring(double __val)
2950  {
2951  const int __n =
2952  __gnu_cxx::__numeric_traits<double>::__max_exponent10 + 20;
2953  return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
2954  L"%f", __val);
2955  }
2956 
2957  inline wstring
2958  to_wstring(long double __val)
2959  {
2960  const int __n =
2961  __gnu_cxx::__numeric_traits<long double>::__max_exponent10 + 20;
2962  return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
2963  L"%Lf", __val);
2964  }
2965 #endif
2966 
2967 _GLIBCXX_END_NAMESPACE_VERSION
2968 } // namespace
2969 
2970 #endif /* __GXX_EXPERIMENTAL_CXX0X__ && _GLIBCXX_USE_C99 ... */
2971 
2972 #ifdef __GXX_EXPERIMENTAL_CXX0X__
2973 
2974 #include <bits/functional_hash.h>
2975 
2976 namespace std _GLIBCXX_VISIBILITY(default)
2977 {
2978 _GLIBCXX_BEGIN_NAMESPACE_VERSION
2979 
2980  // DR 1182.
2981 
2982 #ifndef _GLIBCXX_COMPATIBILITY_CXX0X
2983  /// std::hash specialization for string.
2984  template<>
2985  struct hash<string>
2986  : public __hash_base<size_t, string>
2987  {
2988  size_t
2989  operator()(const string& __s) const
2990  { return std::_Hash_impl::hash(__s.data(), __s.length()); }
2991  };
2992 
2993 #ifdef _GLIBCXX_USE_WCHAR_T
2994  /// std::hash specialization for wstring.
2995  template<>
2996  struct hash<wstring>
2997  : public __hash_base<size_t, wstring>
2998  {
2999  size_t
3000  operator()(const wstring& __s) const
3001  { return std::_Hash_impl::hash(__s.data(),
3002  __s.length() * sizeof(wchar_t)); }
3003  };
3004 #endif
3005 #endif /* _GLIBCXX_COMPATIBILITY_CXX0X */
3006 
3007 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
3008  /// std::hash specialization for u16string.
3009  template<>
3010  struct hash<u16string>
3011  : public __hash_base<size_t, u16string>
3012  {
3013  size_t
3014  operator()(const u16string& __s) const
3015  { return std::_Hash_impl::hash(__s.data(),
3016  __s.length() * sizeof(char16_t)); }
3017  };
3018 
3019  /// std::hash specialization for u32string.
3020  template<>
3021  struct hash<u32string>
3022  : public __hash_base<size_t, u32string>
3023  {
3024  size_t
3025  operator()(const u32string& __s) const
3026  { return std::_Hash_impl::hash(__s.data(),
3027  __s.length() * sizeof(char32_t)); }
3028  };
3029 #endif
3030 
3031 _GLIBCXX_END_NAMESPACE_VERSION
3032 } // namespace
3033 
3034 #endif /* __GXX_EXPERIMENTAL_CXX0X__ */
3035 
3036 #endif /* _BASIC_STRING_H */