1// Map implementation -*- C++ -*-
2
3// Copyright (C) 2001-2017 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996,1997
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file bits/stl_map.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{map}
54 */
55
56#ifndef _STL_MAP_H
57#define _STL_MAP_H 1
58
59#include <bits/functexcept.h>
60#include <bits/concept_check.h>
61#if __cplusplus >= 201103L
62#include <initializer_list>
63#include <tuple>
64#endif
65
66namespace std _GLIBCXX_VISIBILITY(default)
67{
68_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
69
70 template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
71 class multimap;
72
73 /**
74 * @brief A standard container made up of (key,value) pairs, which can be
75 * retrieved based on a key, in logarithmic time.
76 *
77 * @ingroup associative_containers
78 *
79 * @tparam _Key Type of key objects.
80 * @tparam _Tp Type of mapped objects.
81 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
82 * @tparam _Alloc Allocator type, defaults to
83 * allocator<pair<const _Key, _Tp>.
84 *
85 * Meets the requirements of a <a href="tables.html#65">container</a>, a
86 * <a href="tables.html#66">reversible container</a>, and an
87 * <a href="tables.html#69">associative container</a> (using unique keys).
88 * For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the
89 * value_type is std::pair<const Key,T>.
90 *
91 * Maps support bidirectional iterators.
92 *
93 * The private tree data is declared exactly the same way for map and
94 * multimap; the distinction is made entirely in how the tree functions are
95 * called (*_unique versus *_equal, same as the standard).
96 */
97 template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>,
98 typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
99 class map
100 {
101 public:
102 typedef _Key key_type;
103 typedef _Tp mapped_type;
104 typedef std::pair<const _Key, _Tp> value_type;
105 typedef _Compare key_compare;
106 typedef _Alloc allocator_type;
107
108 private:
109#ifdef _GLIBCXX_CONCEPT_CHECKS
110 // concept requirements
111 typedef typename _Alloc::value_type _Alloc_value_type;
112# if __cplusplus < 201103L
113 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
114# endif
115 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
116 _BinaryFunctionConcept)
117 __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
118#endif
119
120 public:
121 class value_compare
122 : public std::binary_function<value_type, value_type, bool>
123 {
124 friend class map<_Key, _Tp, _Compare, _Alloc>;
125 protected:
126 _Compare comp;
127
128 value_compare(_Compare __c)
129 : comp(__c) { }
130
131 public:
132 bool operator()(const value_type& __x, const value_type& __y) const
133 { return comp(__x.first, __y.first); }
134 };
135
136 private:
137 /// This turns a red-black tree into a [multi]map.
138 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
139 rebind<value_type>::other _Pair_alloc_type;
140
141 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
142 key_compare, _Pair_alloc_type> _Rep_type;
143
144 /// The actual tree structure.
145 _Rep_type _M_t;
146
147 typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
148
149 public:
150 // many of these are specified differently in ISO, but the following are
151 // "functionally equivalent"
152 typedef typename _Alloc_traits::pointer pointer;
153 typedef typename _Alloc_traits::const_pointer const_pointer;
154 typedef typename _Alloc_traits::reference reference;
155 typedef typename _Alloc_traits::const_reference const_reference;
156 typedef typename _Rep_type::iterator iterator;
157 typedef typename _Rep_type::const_iterator const_iterator;
158 typedef typename _Rep_type::size_type size_type;
159 typedef typename _Rep_type::difference_type difference_type;
160 typedef typename _Rep_type::reverse_iterator reverse_iterator;
161 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
162
163#if __cplusplus > 201402L
164 using node_type = typename _Rep_type::node_type;
165 using insert_return_type = typename _Rep_type::insert_return_type;
166#endif
167
168 // [23.3.1.1] construct/copy/destroy
169 // (get_allocator() is also listed in this section)
170
171 /**
172 * @brief Default constructor creates no elements.
173 */
174#if __cplusplus < 201103L
175 map() : _M_t() { }
176#else
177 map() = default;
178#endif
179
180 /**
181 * @brief Creates a %map with no elements.
182 * @param __comp A comparison object.
183 * @param __a An allocator object.
184 */
185 explicit
186 map(const _Compare& __comp,
187 const allocator_type& __a = allocator_type())
188 : _M_t(__comp, _Pair_alloc_type(__a)) { }
189
190 /**
191 * @brief %Map copy constructor.
192 *
193 * Whether the allocator is copied depends on the allocator traits.
194 */
195#if __cplusplus < 201103L
196 map(const map& __x)
197 : _M_t(__x._M_t) { }
198#else
199 map(const map&) = default;
200
201 /**
202 * @brief %Map move constructor.
203 *
204 * The newly-created %map contains the exact contents of the moved
205 * instance. The moved instance is a valid, but unspecified, %map.
206 */
207 map(map&&) = default;
208
209 /**
210 * @brief Builds a %map from an initializer_list.
211 * @param __l An initializer_list.
212 * @param __comp A comparison object.
213 * @param __a An allocator object.
214 *
215 * Create a %map consisting of copies of the elements in the
216 * initializer_list @a __l.
217 * This is linear in N if the range is already sorted, and NlogN
218 * otherwise (where N is @a __l.size()).
219 */
220 map(initializer_list<value_type> __l,
221 const _Compare& __comp = _Compare(),
222 const allocator_type& __a = allocator_type())
223 : _M_t(__comp, _Pair_alloc_type(__a))
224 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
225
226 /// Allocator-extended default constructor.
227 explicit
228 map(const allocator_type& __a)
229 : _M_t(_Compare(), _Pair_alloc_type(__a)) { }
230
231 /// Allocator-extended copy constructor.
232 map(const map& __m, const allocator_type& __a)
233 : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
234
235 /// Allocator-extended move constructor.
236 map(map&& __m, const allocator_type& __a)
237 noexcept(is_nothrow_copy_constructible<_Compare>::value
238 && _Alloc_traits::_S_always_equal())
239 : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
240
241 /// Allocator-extended initialier-list constructor.
242 map(initializer_list<value_type> __l, const allocator_type& __a)
243 : _M_t(_Compare(), _Pair_alloc_type(__a))
244 { _M_t._M_insert_unique(__l.begin(), __l.end()); }
245
246 /// Allocator-extended range constructor.
247 template<typename _InputIterator>
248 map(_InputIterator __first, _InputIterator __last,
249 const allocator_type& __a)
250 : _M_t(_Compare(), _Pair_alloc_type(__a))
251 { _M_t._M_insert_unique(__first, __last); }
252#endif
253
254 /**
255 * @brief Builds a %map from a range.
256 * @param __first An input iterator.
257 * @param __last An input iterator.
258 *
259 * Create a %map consisting of copies of the elements from
260 * [__first,__last). This is linear in N if the range is
261 * already sorted, and NlogN otherwise (where N is
262 * distance(__first,__last)).
263 */
264 template<typename _InputIterator>
265 map(_InputIterator __first, _InputIterator __last)
266 : _M_t()
267 { _M_t._M_insert_unique(__first, __last); }
268
269 /**
270 * @brief Builds a %map from a range.
271 * @param __first An input iterator.
272 * @param __last An input iterator.
273 * @param __comp A comparison functor.
274 * @param __a An allocator object.
275 *
276 * Create a %map consisting of copies of the elements from
277 * [__first,__last). This is linear in N if the range is
278 * already sorted, and NlogN otherwise (where N is
279 * distance(__first,__last)).
280 */
281 template<typename _InputIterator>
282 map(_InputIterator __first, _InputIterator __last,
283 const _Compare& __comp,
284 const allocator_type& __a = allocator_type())
285 : _M_t(__comp, _Pair_alloc_type(__a))
286 { _M_t._M_insert_unique(__first, __last); }
287
288#if __cplusplus >= 201103L
289 /**
290 * The dtor only erases the elements, and note that if the elements
291 * themselves are pointers, the pointed-to memory is not touched in any
292 * way. Managing the pointer is the user's responsibility.
293 */
294 ~map() = default;
295#endif
296
297 /**
298 * @brief %Map assignment operator.
299 *
300 * Whether the allocator is copied depends on the allocator traits.
301 */
302#if __cplusplus < 201103L
303 map&
304 operator=(const map& __x)
305 {
306 _M_t = __x._M_t;
307 return *this;
308 }
309#else
310 map&
311 operator=(const map&) = default;
312
313 /// Move assignment operator.
314 map&
315 operator=(map&&) = default;
316
317 /**
318 * @brief %Map list assignment operator.
319 * @param __l An initializer_list.
320 *
321 * This function fills a %map with copies of the elements in the
322 * initializer list @a __l.
323 *
324 * Note that the assignment completely changes the %map and
325 * that the resulting %map's size is the same as the number
326 * of elements assigned.
327 */
328 map&
329 operator=(initializer_list<value_type> __l)
330 {
331 _M_t._M_assign_unique(__l.begin(), __l.end());
332 return *this;
333 }
334#endif
335
336 /// Get a copy of the memory allocation object.
337 allocator_type
338 get_allocator() const _GLIBCXX_NOEXCEPT
339 { return allocator_type(_M_t.get_allocator()); }
340
341 // iterators
342 /**
343 * Returns a read/write iterator that points to the first pair in the
344 * %map.
345 * Iteration is done in ascending order according to the keys.
346 */
347 iterator
348 begin() _GLIBCXX_NOEXCEPT
349 { return _M_t.begin(); }
350
351 /**
352 * Returns a read-only (constant) iterator that points to the first pair
353 * in the %map. Iteration is done in ascending order according to the
354 * keys.
355 */
356 const_iterator
357 begin() const _GLIBCXX_NOEXCEPT
358 { return _M_t.begin(); }
359
360 /**
361 * Returns a read/write iterator that points one past the last
362 * pair in the %map. Iteration is done in ascending order
363 * according to the keys.
364 */
365 iterator
366 end() _GLIBCXX_NOEXCEPT
367 { return _M_t.end(); }
368
369 /**
370 * Returns a read-only (constant) iterator that points one past the last
371 * pair in the %map. Iteration is done in ascending order according to
372 * the keys.
373 */
374 const_iterator
375 end() const _GLIBCXX_NOEXCEPT
376 { return _M_t.end(); }
377
378 /**
379 * Returns a read/write reverse iterator that points to the last pair in
380 * the %map. Iteration is done in descending order according to the
381 * keys.
382 */
383 reverse_iterator
384 rbegin() _GLIBCXX_NOEXCEPT
385 { return _M_t.rbegin(); }
386
387 /**
388 * Returns a read-only (constant) reverse iterator that points to the
389 * last pair in the %map. Iteration is done in descending order
390 * according to the keys.
391 */
392 const_reverse_iterator
393 rbegin() const _GLIBCXX_NOEXCEPT
394 { return _M_t.rbegin(); }
395
396 /**
397 * Returns a read/write reverse iterator that points to one before the
398 * first pair in the %map. Iteration is done in descending order
399 * according to the keys.
400 */
401 reverse_iterator
402 rend() _GLIBCXX_NOEXCEPT
403 { return _M_t.rend(); }
404
405 /**
406 * Returns a read-only (constant) reverse iterator that points to one
407 * before the first pair in the %map. Iteration is done in descending
408 * order according to the keys.
409 */
410 const_reverse_iterator
411 rend() const _GLIBCXX_NOEXCEPT
412 { return _M_t.rend(); }
413
414#if __cplusplus >= 201103L
415 /**
416 * Returns a read-only (constant) iterator that points to the first pair
417 * in the %map. Iteration is done in ascending order according to the
418 * keys.
419 */
420 const_iterator
421 cbegin() const noexcept
422 { return _M_t.begin(); }
423
424 /**
425 * Returns a read-only (constant) iterator that points one past the last
426 * pair in the %map. Iteration is done in ascending order according to
427 * the keys.
428 */
429 const_iterator
430 cend() const noexcept
431 { return _M_t.end(); }
432
433 /**
434 * Returns a read-only (constant) reverse iterator that points to the
435 * last pair in the %map. Iteration is done in descending order
436 * according to the keys.
437 */
438 const_reverse_iterator
439 crbegin() const noexcept
440 { return _M_t.rbegin(); }
441
442 /**
443 * Returns a read-only (constant) reverse iterator that points to one
444 * before the first pair in the %map. Iteration is done in descending
445 * order according to the keys.
446 */
447 const_reverse_iterator
448 crend() const noexcept
449 { return _M_t.rend(); }
450#endif
451
452 // capacity
453 /** Returns true if the %map is empty. (Thus begin() would equal
454 * end().)
455 */
456 bool
457 empty() const _GLIBCXX_NOEXCEPT
458 { return _M_t.empty(); }
459
460 /** Returns the size of the %map. */
461 size_type
462 size() const _GLIBCXX_NOEXCEPT
463 { return _M_t.size(); }
464
465 /** Returns the maximum size of the %map. */
466 size_type
467 max_size() const _GLIBCXX_NOEXCEPT
468 { return _M_t.max_size(); }
469
470 // [23.3.1.2] element access
471 /**
472 * @brief Subscript ( @c [] ) access to %map data.
473 * @param __k The key for which data should be retrieved.
474 * @return A reference to the data of the (key,data) %pair.
475 *
476 * Allows for easy lookup with the subscript ( @c [] )
477 * operator. Returns data associated with the key specified in
478 * subscript. If the key does not exist, a pair with that key
479 * is created using default values, which is then returned.
480 *
481 * Lookup requires logarithmic time.
482 */
483 mapped_type&
484 operator[](const key_type& __k)
485 {
486 // concept requirements
487 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
488
489 iterator __i = lower_bound(__k);
490 // __i->first is greater than or equivalent to __k.
491 if (__i == end() || key_comp()(__k, (*__i).first))
492#if __cplusplus >= 201103L
493 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
494 std::tuple<const key_type&>(__k),
495 std::tuple<>());
496#else
497 __i = insert(__i, value_type(__k, mapped_type()));
498#endif
499 return (*__i).second;
500 }
501
502#if __cplusplus >= 201103L
503 mapped_type&
504 operator[](key_type&& __k)
505 {
506 // concept requirements
507 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
508
509 iterator __i = lower_bound(__k);
510 // __i->first is greater than or equivalent to __k.
511 if (__i == end() || key_comp()(__k, (*__i).first))
512 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
513 std::forward_as_tuple(std::move(__k)),
514 std::tuple<>());
515 return (*__i).second;
516 }
517#endif
518
519 // _GLIBCXX_RESOLVE_LIB_DEFECTS
520 // DR 464. Suggestion for new member functions in standard containers.
521 /**
522 * @brief Access to %map data.
523 * @param __k The key for which data should be retrieved.
524 * @return A reference to the data whose key is equivalent to @a __k, if
525 * such a data is present in the %map.
526 * @throw std::out_of_range If no such data is present.
527 */
528 mapped_type&
529 at(const key_type& __k)
530 {
531 iterator __i = lower_bound(__k);
532 if (__i == end() || key_comp()(__k, (*__i).first))
533 __throw_out_of_range(__N("map::at"));
534 return (*__i).second;
535 }
536
537 const mapped_type&
538 at(const key_type& __k) const
539 {
540 const_iterator __i = lower_bound(__k);
541 if (__i == end() || key_comp()(__k, (*__i).first))
542 __throw_out_of_range(__N("map::at"));
543 return (*__i).second;
544 }
545
546 // modifiers
547#if __cplusplus >= 201103L
548 /**
549 * @brief Attempts to build and insert a std::pair into the %map.
550 *
551 * @param __args Arguments used to generate a new pair instance (see
552 * std::piecewise_contruct for passing arguments to each
553 * part of the pair constructor).
554 *
555 * @return A pair, of which the first element is an iterator that points
556 * to the possibly inserted pair, and the second is a bool that
557 * is true if the pair was actually inserted.
558 *
559 * This function attempts to build and insert a (key, value) %pair into
560 * the %map.
561 * A %map relies on unique keys and thus a %pair is only inserted if its
562 * first element (the key) is not already present in the %map.
563 *
564 * Insertion requires logarithmic time.
565 */
566 template<typename... _Args>
567 std::pair<iterator, bool>
568 emplace(_Args&&... __args)
569 { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
570
571 /**
572 * @brief Attempts to build and insert a std::pair into the %map.
573 *
574 * @param __pos An iterator that serves as a hint as to where the pair
575 * should be inserted.
576 * @param __args Arguments used to generate a new pair instance (see
577 * std::piecewise_contruct for passing arguments to each
578 * part of the pair constructor).
579 * @return An iterator that points to the element with key of the
580 * std::pair built from @a __args (may or may not be that
581 * std::pair).
582 *
583 * This function is not concerned about whether the insertion took place,
584 * and thus does not return a boolean like the single-argument emplace()
585 * does.
586 * Note that the first parameter is only a hint and can potentially
587 * improve the performance of the insertion process. A bad hint would
588 * cause no gains in efficiency.
589 *
590 * See
591 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
592 * for more on @a hinting.
593 *
594 * Insertion requires logarithmic time (if the hint is not taken).
595 */
596 template<typename... _Args>
597 iterator
598 emplace_hint(const_iterator __pos, _Args&&... __args)
599 {
600 return _M_t._M_emplace_hint_unique(__pos,
601 std::forward<_Args>(__args)...);
602 }
603#endif
604
605#if __cplusplus > 201402L
606 /// Extract a node.
607 node_type
608 extract(const_iterator __pos)
609 {
610 __glibcxx_assert(__pos != end());
611 return _M_t.extract(__pos);
612 }
613
614 /// Extract a node.
615 node_type
616 extract(const key_type& __x)
617 { return _M_t.extract(__x); }
618
619 /// Re-insert an extracted node.
620 insert_return_type
621 insert(node_type&& __nh)
622 { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
623
624 /// Re-insert an extracted node.
625 iterator
626 insert(const_iterator __hint, node_type&& __nh)
627 { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
628
629 template<typename, typename>
630 friend class _Rb_tree_merge_helper;
631
632 template<typename _C2>
633 void
634 merge(map<_Key, _Tp, _C2, _Alloc>& __source)
635 {
636 using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
637 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
638 }
639
640 template<typename _C2>
641 void
642 merge(map<_Key, _Tp, _C2, _Alloc>&& __source)
643 { merge(__source); }
644
645 template<typename _C2>
646 void
647 merge(multimap<_Key, _Tp, _C2, _Alloc>& __source)
648 {
649 using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
650 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
651 }
652
653 template<typename _C2>
654 void
655 merge(multimap<_Key, _Tp, _C2, _Alloc>&& __source)
656 { merge(__source); }
657#endif // C++17
658
659#if __cplusplus > 201402L
660#define __cpp_lib_map_try_emplace 201411
661 /**
662 * @brief Attempts to build and insert a std::pair into the %map.
663 *
664 * @param __k Key to use for finding a possibly existing pair in
665 * the map.
666 * @param __args Arguments used to generate the .second for a new pair
667 * instance.
668 *
669 * @return A pair, of which the first element is an iterator that points
670 * to the possibly inserted pair, and the second is a bool that
671 * is true if the pair was actually inserted.
672 *
673 * This function attempts to build and insert a (key, value) %pair into
674 * the %map.
675 * A %map relies on unique keys and thus a %pair is only inserted if its
676 * first element (the key) is not already present in the %map.
677 * If a %pair is not inserted, this function has no effect.
678 *
679 * Insertion requires logarithmic time.
680 */
681 template <typename... _Args>
682 pair<iterator, bool>
683 try_emplace(const key_type& __k, _Args&&... __args)
684 {
685 iterator __i = lower_bound(__k);
686 if (__i == end() || key_comp()(__k, (*__i).first))
687 {
688 __i = emplace_hint(__i, std::piecewise_construct,
689 std::forward_as_tuple(__k),
690 std::forward_as_tuple(
691 std::forward<_Args>(__args)...));
692 return {__i, true};
693 }
694 return {__i, false};
695 }
696
697 // move-capable overload
698 template <typename... _Args>
699 pair<iterator, bool>
700 try_emplace(key_type&& __k, _Args&&... __args)
701 {
702 iterator __i = lower_bound(__k);
703 if (__i == end() || key_comp()(__k, (*__i).first))
704 {
705 __i = emplace_hint(__i, std::piecewise_construct,
706 std::forward_as_tuple(std::move(__k)),
707 std::forward_as_tuple(
708 std::forward<_Args>(__args)...));
709 return {__i, true};
710 }
711 return {__i, false};
712 }
713
714 /**
715 * @brief Attempts to build and insert a std::pair into the %map.
716 *
717 * @param __hint An iterator that serves as a hint as to where the
718 * pair should be inserted.
719 * @param __k Key to use for finding a possibly existing pair in
720 * the map.
721 * @param __args Arguments used to generate the .second for a new pair
722 * instance.
723 * @return An iterator that points to the element with key of the
724 * std::pair built from @a __args (may or may not be that
725 * std::pair).
726 *
727 * This function is not concerned about whether the insertion took place,
728 * and thus does not return a boolean like the single-argument
729 * try_emplace() does. However, if insertion did not take place,
730 * this function has no effect.
731 * Note that the first parameter is only a hint and can potentially
732 * improve the performance of the insertion process. A bad hint would
733 * cause no gains in efficiency.
734 *
735 * See
736 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
737 * for more on @a hinting.
738 *
739 * Insertion requires logarithmic time (if the hint is not taken).
740 */
741 template <typename... _Args>
742 iterator
743 try_emplace(const_iterator __hint, const key_type& __k,
744 _Args&&... __args)
745 {
746 iterator __i;
747 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
748 if (__true_hint.second)
749 __i = emplace_hint(iterator(__true_hint.second),
750 std::piecewise_construct,
751 std::forward_as_tuple(__k),
752 std::forward_as_tuple(
753 std::forward<_Args>(__args)...));
754 else
755 __i = iterator(__true_hint.first);
756 return __i;
757 }
758
759 // move-capable overload
760 template <typename... _Args>
761 iterator
762 try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
763 {
764 iterator __i;
765 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
766 if (__true_hint.second)
767 __i = emplace_hint(iterator(__true_hint.second),
768 std::piecewise_construct,
769 std::forward_as_tuple(std::move(__k)),
770 std::forward_as_tuple(
771 std::forward<_Args>(__args)...));
772 else
773 __i = iterator(__true_hint.first);
774 return __i;
775 }
776#endif
777
778 /**
779 * @brief Attempts to insert a std::pair into the %map.
780 * @param __x Pair to be inserted (see std::make_pair for easy
781 * creation of pairs).
782 *
783 * @return A pair, of which the first element is an iterator that
784 * points to the possibly inserted pair, and the second is
785 * a bool that is true if the pair was actually inserted.
786 *
787 * This function attempts to insert a (key, value) %pair into the %map.
788 * A %map relies on unique keys and thus a %pair is only inserted if its
789 * first element (the key) is not already present in the %map.
790 *
791 * Insertion requires logarithmic time.
792 * @{
793 */
794 std::pair<iterator, bool>
795 insert(const value_type& __x)
796 { return _M_t._M_insert_unique(__x); }
797
798#if __cplusplus >= 201103L
799 // _GLIBCXX_RESOLVE_LIB_DEFECTS
800 // 2354. Unnecessary copying when inserting into maps with braced-init
801 std::pair<iterator, bool>
802 insert(value_type&& __x)
803 { return _M_t._M_insert_unique(std::move(__x)); }
804
805 template<typename _Pair>
806 __enable_if_t<is_constructible<value_type, _Pair>::value,
807 pair<iterator, bool>>
808 insert(_Pair&& __x)
809 { return _M_t._M_emplace_unique(std::forward<_Pair>(__x)); }
810#endif
811 // @}
812
813#if __cplusplus >= 201103L
814 /**
815 * @brief Attempts to insert a list of std::pairs into the %map.
816 * @param __list A std::initializer_list<value_type> of pairs to be
817 * inserted.
818 *
819 * Complexity similar to that of the range constructor.
820 */
821 void
822 insert(std::initializer_list<value_type> __list)
823 { insert(__list.begin(), __list.end()); }
824#endif
825
826 /**
827 * @brief Attempts to insert a std::pair into the %map.
828 * @param __position An iterator that serves as a hint as to where the
829 * pair should be inserted.
830 * @param __x Pair to be inserted (see std::make_pair for easy creation
831 * of pairs).
832 * @return An iterator that points to the element with key of
833 * @a __x (may or may not be the %pair passed in).
834 *
835
836 * This function is not concerned about whether the insertion
837 * took place, and thus does not return a boolean like the
838 * single-argument insert() does. Note that the first
839 * parameter is only a hint and can potentially improve the
840 * performance of the insertion process. A bad hint would
841 * cause no gains in efficiency.
842 *
843 * See
844 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
845 * for more on @a hinting.
846 *
847 * Insertion requires logarithmic time (if the hint is not taken).
848 * @{
849 */
850 iterator
851#if __cplusplus >= 201103L
852 insert(const_iterator __position, const value_type& __x)
853#else
854 insert(iterator __position, const value_type& __x)
855#endif
856 { return _M_t._M_insert_unique_(__position, __x); }
857
858#if __cplusplus >= 201103L
859 // _GLIBCXX_RESOLVE_LIB_DEFECTS
860 // 2354. Unnecessary copying when inserting into maps with braced-init
861 iterator
862 insert(const_iterator __position, value_type&& __x)
863 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
864
865 template<typename _Pair>
866 __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
867 insert(const_iterator __position, _Pair&& __x)
868 {
869 return _M_t._M_emplace_hint_unique(__position,
870 std::forward<_Pair>(__x));
871 }
872#endif
873 // @}
874
875 /**
876 * @brief Template function that attempts to insert a range of elements.
877 * @param __first Iterator pointing to the start of the range to be
878 * inserted.
879 * @param __last Iterator pointing to the end of the range.
880 *
881 * Complexity similar to that of the range constructor.
882 */
883 template<typename _InputIterator>
884 void
885 insert(_InputIterator __first, _InputIterator __last)
886 { _M_t._M_insert_unique(__first, __last); }
887
888#if __cplusplus > 201402L
889#define __cpp_lib_map_insertion 201411
890 /**
891 * @brief Attempts to insert or assign a std::pair into the %map.
892 * @param __k Key to use for finding a possibly existing pair in
893 * the map.
894 * @param __obj Argument used to generate the .second for a pair
895 * instance.
896 *
897 * @return A pair, of which the first element is an iterator that
898 * points to the possibly inserted pair, and the second is
899 * a bool that is true if the pair was actually inserted.
900 *
901 * This function attempts to insert a (key, value) %pair into the %map.
902 * A %map relies on unique keys and thus a %pair is only inserted if its
903 * first element (the key) is not already present in the %map.
904 * If the %pair was already in the %map, the .second of the %pair
905 * is assigned from __obj.
906 *
907 * Insertion requires logarithmic time.
908 */
909 template <typename _Obj>
910 pair<iterator, bool>
911 insert_or_assign(const key_type& __k, _Obj&& __obj)
912 {
913 iterator __i = lower_bound(__k);
914 if (__i == end() || key_comp()(__k, (*__i).first))
915 {
916 __i = emplace_hint(__i, std::piecewise_construct,
917 std::forward_as_tuple(__k),
918 std::forward_as_tuple(
919 std::forward<_Obj>(__obj)));
920 return {__i, true};
921 }
922 (*__i).second = std::forward<_Obj>(__obj);
923 return {__i, false};
924 }
925
926 // move-capable overload
927 template <typename _Obj>
928 pair<iterator, bool>
929 insert_or_assign(key_type&& __k, _Obj&& __obj)
930 {
931 iterator __i = lower_bound(__k);
932 if (__i == end() || key_comp()(__k, (*__i).first))
933 {
934 __i = emplace_hint(__i, std::piecewise_construct,
935 std::forward_as_tuple(std::move(__k)),
936 std::forward_as_tuple(
937 std::forward<_Obj>(__obj)));
938 return {__i, true};
939 }
940 (*__i).second = std::forward<_Obj>(__obj);
941 return {__i, false};
942 }
943
944 /**
945 * @brief Attempts to insert or assign a std::pair into the %map.
946 * @param __hint An iterator that serves as a hint as to where the
947 * pair should be inserted.
948 * @param __k Key to use for finding a possibly existing pair in
949 * the map.
950 * @param __obj Argument used to generate the .second for a pair
951 * instance.
952 *
953 * @return An iterator that points to the element with key of
954 * @a __x (may or may not be the %pair passed in).
955 *
956 * This function attempts to insert a (key, value) %pair into the %map.
957 * A %map relies on unique keys and thus a %pair is only inserted if its
958 * first element (the key) is not already present in the %map.
959 * If the %pair was already in the %map, the .second of the %pair
960 * is assigned from __obj.
961 *
962 * Insertion requires logarithmic time.
963 */
964 template <typename _Obj>
965 iterator
966 insert_or_assign(const_iterator __hint,
967 const key_type& __k, _Obj&& __obj)
968 {
969 iterator __i;
970 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
971 if (__true_hint.second)
972 {
973 return emplace_hint(iterator(__true_hint.second),
974 std::piecewise_construct,
975 std::forward_as_tuple(__k),
976 std::forward_as_tuple(
977 std::forward<_Obj>(__obj)));
978 }
979 __i = iterator(__true_hint.first);
980 (*__i).second = std::forward<_Obj>(__obj);
981 return __i;
982 }
983
984 // move-capable overload
985 template <typename _Obj>
986 iterator
987 insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
988 {
989 iterator __i;
990 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
991 if (__true_hint.second)
992 {
993 return emplace_hint(iterator(__true_hint.second),
994 std::piecewise_construct,
995 std::forward_as_tuple(std::move(__k)),
996 std::forward_as_tuple(
997 std::forward<_Obj>(__obj)));
998 }
999 __i = iterator(__true_hint.first);
1000 (*__i).second = std::forward<_Obj>(__obj);
1001 return __i;
1002 }
1003#endif
1004
1005#if __cplusplus >= 201103L
1006 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1007 // DR 130. Associative erase should return an iterator.
1008 /**
1009 * @brief Erases an element from a %map.
1010 * @param __position An iterator pointing to the element to be erased.
1011 * @return An iterator pointing to the element immediately following
1012 * @a position prior to the element being erased. If no such
1013 * element exists, end() is returned.
1014 *
1015 * This function erases an element, pointed to by the given
1016 * iterator, from a %map. Note that this function only erases
1017 * the element, and that if the element is itself a pointer,
1018 * the pointed-to memory is not touched in any way. Managing
1019 * the pointer is the user's responsibility.
1020 *
1021 * @{
1022 */
1023 iterator
1024 erase(const_iterator __position)
1025 { return _M_t.erase(__position); }
1026
1027 // LWG 2059
1028 _GLIBCXX_ABI_TAG_CXX11
1029 iterator
1030 erase(iterator __position)
1031 { return _M_t.erase(__position); }
1032 // @}
1033#else
1034 /**
1035 * @brief Erases an element from a %map.
1036 * @param __position An iterator pointing to the element to be erased.
1037 *
1038 * This function erases an element, pointed to by the given
1039 * iterator, from a %map. Note that this function only erases
1040 * the element, and that if the element is itself a pointer,
1041 * the pointed-to memory is not touched in any way. Managing
1042 * the pointer is the user's responsibility.
1043 */
1044 void
1045 erase(iterator __position)
1046 { _M_t.erase(__position); }
1047#endif
1048
1049 /**
1050 * @brief Erases elements according to the provided key.
1051 * @param __x Key of element to be erased.
1052 * @return The number of elements erased.
1053 *
1054 * This function erases all the elements located by the given key from
1055 * a %map.
1056 * Note that this function only erases the element, and that if
1057 * the element is itself a pointer, the pointed-to memory is not touched
1058 * in any way. Managing the pointer is the user's responsibility.
1059 */
1060 size_type
1061 erase(const key_type& __x)
1062 { return _M_t.erase(__x); }
1063
1064#if __cplusplus >= 201103L
1065 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1066 // DR 130. Associative erase should return an iterator.
1067 /**
1068 * @brief Erases a [first,last) range of elements from a %map.
1069 * @param __first Iterator pointing to the start of the range to be
1070 * erased.
1071 * @param __last Iterator pointing to the end of the range to
1072 * be erased.
1073 * @return The iterator @a __last.
1074 *
1075 * This function erases a sequence of elements from a %map.
1076 * Note that this function only erases the element, and that if
1077 * the element is itself a pointer, the pointed-to memory is not touched
1078 * in any way. Managing the pointer is the user's responsibility.
1079 */
1080 iterator
1081 erase(const_iterator __first, const_iterator __last)
1082 { return _M_t.erase(__first, __last); }
1083#else
1084 /**
1085 * @brief Erases a [__first,__last) range of elements from a %map.
1086 * @param __first Iterator pointing to the start of the range to be
1087 * erased.
1088 * @param __last Iterator pointing to the end of the range to
1089 * be erased.
1090 *
1091 * This function erases a sequence of elements from a %map.
1092 * Note that this function only erases the element, and that if
1093 * the element is itself a pointer, the pointed-to memory is not touched
1094 * in any way. Managing the pointer is the user's responsibility.
1095 */
1096 void
1097 erase(iterator __first, iterator __last)
1098 { _M_t.erase(__first, __last); }
1099#endif
1100
1101 /**
1102 * @brief Swaps data with another %map.
1103 * @param __x A %map of the same element and allocator types.
1104 *
1105 * This exchanges the elements between two maps in constant
1106 * time. (It is only swapping a pointer, an integer, and an
1107 * instance of the @c Compare type (which itself is often
1108 * stateless and empty), so it should be quite fast.) Note
1109 * that the global std::swap() function is specialized such
1110 * that std::swap(m1,m2) will feed to this function.
1111 *
1112 * Whether the allocators are swapped depends on the allocator traits.
1113 */
1114 void
1115 swap(map& __x)
1116 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
1117 { _M_t.swap(__x._M_t); }
1118
1119 /**
1120 * Erases all elements in a %map. Note that this function only
1121 * erases the elements, and that if the elements themselves are
1122 * pointers, the pointed-to memory is not touched in any way.
1123 * Managing the pointer is the user's responsibility.
1124 */
1125 void
1126 clear() _GLIBCXX_NOEXCEPT
1127 { _M_t.clear(); }
1128
1129 // observers
1130 /**
1131 * Returns the key comparison object out of which the %map was
1132 * constructed.
1133 */
1134 key_compare
1135 key_comp() const
1136 { return _M_t.key_comp(); }
1137
1138 /**
1139 * Returns a value comparison object, built from the key comparison
1140 * object out of which the %map was constructed.
1141 */
1142 value_compare
1143 value_comp() const
1144 { return value_compare(_M_t.key_comp()); }
1145
1146 // [23.3.1.3] map operations
1147
1148 //@{
1149 /**
1150 * @brief Tries to locate an element in a %map.
1151 * @param __x Key of (key, value) %pair to be located.
1152 * @return Iterator pointing to sought-after element, or end() if not
1153 * found.
1154 *
1155 * This function takes a key and tries to locate the element with which
1156 * the key matches. If successful the function returns an iterator
1157 * pointing to the sought after %pair. If unsuccessful it returns the
1158 * past-the-end ( @c end() ) iterator.
1159 */
1160
1161 iterator
1162 find(const key_type& __x)
1163 { return _M_t.find(__x); }
1164
1165#if __cplusplus > 201103L
1166 template<typename _Kt>
1167 auto
1168 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
1169 { return _M_t._M_find_tr(__x); }
1170#endif
1171 //@}
1172
1173 //@{
1174 /**
1175 * @brief Tries to locate an element in a %map.
1176 * @param __x Key of (key, value) %pair to be located.
1177 * @return Read-only (constant) iterator pointing to sought-after
1178 * element, or end() if not found.
1179 *
1180 * This function takes a key and tries to locate the element with which
1181 * the key matches. If successful the function returns a constant
1182 * iterator pointing to the sought after %pair. If unsuccessful it
1183 * returns the past-the-end ( @c end() ) iterator.
1184 */
1185
1186 const_iterator
1187 find(const key_type& __x) const
1188 { return _M_t.find(__x); }
1189
1190#if __cplusplus > 201103L
1191 template<typename _Kt>
1192 auto
1193 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
1194 { return _M_t._M_find_tr(__x); }
1195#endif
1196 //@}
1197
1198 //@{
1199 /**
1200 * @brief Finds the number of elements with given key.
1201 * @param __x Key of (key, value) pairs to be located.
1202 * @return Number of elements with specified key.
1203 *
1204 * This function only makes sense for multimaps; for map the result will
1205 * either be 0 (not present) or 1 (present).
1206 */
1207 size_type
1208 count(const key_type& __x) const
1209 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
1210
1211#if __cplusplus > 201103L
1212 template<typename _Kt>
1213 auto
1214 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
1215 { return _M_t._M_count_tr(__x); }
1216#endif
1217 //@}
1218
1219 //@{
1220 /**
1221 * @brief Finds the beginning of a subsequence matching given key.
1222 * @param __x Key of (key, value) pair to be located.
1223 * @return Iterator pointing to first element equal to or greater
1224 * than key, or end().
1225 *
1226 * This function returns the first element of a subsequence of elements
1227 * that matches the given key. If unsuccessful it returns an iterator
1228 * pointing to the first element that has a greater value than given key
1229 * or end() if no such element exists.
1230 */
1231 iterator
1232 lower_bound(const key_type& __x)
1233 { return _M_t.lower_bound(__x); }
1234
1235#if __cplusplus > 201103L
1236 template<typename _Kt>
1237 auto
1238 lower_bound(const _Kt& __x)
1239 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
1240 { return iterator(_M_t._M_lower_bound_tr(__x)); }
1241#endif
1242 //@}
1243
1244 //@{
1245 /**
1246 * @brief Finds the beginning of a subsequence matching given key.
1247 * @param __x Key of (key, value) pair to be located.
1248 * @return Read-only (constant) iterator pointing to first element
1249 * equal to or greater than key, or end().
1250 *
1251 * This function returns the first element of a subsequence of elements
1252 * that matches the given key. If unsuccessful it returns an iterator
1253 * pointing to the first element that has a greater value than given key
1254 * or end() if no such element exists.
1255 */
1256 const_iterator
1257 lower_bound(const key_type& __x) const
1258 { return _M_t.lower_bound(__x); }
1259
1260#if __cplusplus > 201103L
1261 template<typename _Kt>
1262 auto
1263 lower_bound(const _Kt& __x) const
1264 -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
1265 { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
1266#endif
1267 //@}
1268
1269 //@{
1270 /**
1271 * @brief Finds the end of a subsequence matching given key.
1272 * @param __x Key of (key, value) pair to be located.
1273 * @return Iterator pointing to the first element
1274 * greater than key, or end().
1275 */
1276 iterator
1277 upper_bound(const key_type& __x)
1278 { return _M_t.upper_bound(__x); }
1279
1280#if __cplusplus > 201103L
1281 template<typename _Kt>
1282 auto
1283 upper_bound(const _Kt& __x)
1284 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
1285 { return iterator(_M_t._M_upper_bound_tr(__x)); }
1286#endif
1287 //@}
1288
1289 //@{
1290 /**
1291 * @brief Finds the end of a subsequence matching given key.
1292 * @param __x Key of (key, value) pair to be located.
1293 * @return Read-only (constant) iterator pointing to first iterator
1294 * greater than key, or end().
1295 */
1296 const_iterator
1297 upper_bound(const key_type& __x) const
1298 { return _M_t.upper_bound(__x); }
1299
1300#if __cplusplus > 201103L
1301 template<typename _Kt>
1302 auto
1303 upper_bound(const _Kt& __x) const
1304 -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
1305 { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
1306#endif
1307 //@}
1308
1309 //@{
1310 /**
1311 * @brief Finds a subsequence matching given key.
1312 * @param __x Key of (key, value) pairs to be located.
1313 * @return Pair of iterators that possibly points to the subsequence
1314 * matching given key.
1315 *
1316 * This function is equivalent to
1317 * @code
1318 * std::make_pair(c.lower_bound(val),
1319 * c.upper_bound(val))
1320 * @endcode
1321 * (but is faster than making the calls separately).
1322 *
1323 * This function probably only makes sense for multimaps.
1324 */
1325 std::pair<iterator, iterator>
1326 equal_range(const key_type& __x)
1327 { return _M_t.equal_range(__x); }
1328
1329#if __cplusplus > 201103L
1330 template<typename _Kt>
1331 auto
1332 equal_range(const _Kt& __x)
1333 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1334 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1335#endif
1336 //@}
1337
1338 //@{
1339 /**
1340 * @brief Finds a subsequence matching given key.
1341 * @param __x Key of (key, value) pairs to be located.
1342 * @return Pair of read-only (constant) iterators that possibly points
1343 * to the subsequence matching given key.
1344 *
1345 * This function is equivalent to
1346 * @code
1347 * std::make_pair(c.lower_bound(val),
1348 * c.upper_bound(val))
1349 * @endcode
1350 * (but is faster than making the calls separately).
1351 *
1352 * This function probably only makes sense for multimaps.
1353 */
1354 std::pair<const_iterator, const_iterator>
1355 equal_range(const key_type& __x) const
1356 { return _M_t.equal_range(__x); }
1357
1358#if __cplusplus > 201103L
1359 template<typename _Kt>
1360 auto
1361 equal_range(const _Kt& __x) const
1362 -> decltype(pair<const_iterator, const_iterator>(
1363 _M_t._M_equal_range_tr(__x)))
1364 {
1365 return pair<const_iterator, const_iterator>(
1366 _M_t._M_equal_range_tr(__x));
1367 }
1368#endif
1369 //@}
1370
1371 template<typename _K1, typename _T1, typename _C1, typename _A1>
1372 friend bool
1373 operator==(const map<_K1, _T1, _C1, _A1>&,
1374 const map<_K1, _T1, _C1, _A1>&);
1375
1376 template<typename _K1, typename _T1, typename _C1, typename _A1>
1377 friend bool
1378 operator<(const map<_K1, _T1, _C1, _A1>&,
1379 const map<_K1, _T1, _C1, _A1>&);
1380 };
1381
1382 /**
1383 * @brief Map equality comparison.
1384 * @param __x A %map.
1385 * @param __y A %map of the same type as @a x.
1386 * @return True iff the size and elements of the maps are equal.
1387 *
1388 * This is an equivalence relation. It is linear in the size of the
1389 * maps. Maps are considered equivalent if their sizes are equal,
1390 * and if corresponding elements compare equal.
1391 */
1392 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1393 inline bool
1394 operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1395 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1396 { return __x._M_t == __y._M_t; }
1397
1398 /**
1399 * @brief Map ordering relation.
1400 * @param __x A %map.
1401 * @param __y A %map of the same type as @a x.
1402 * @return True iff @a x is lexicographically less than @a y.
1403 *
1404 * This is a total ordering relation. It is linear in the size of the
1405 * maps. The elements must be comparable with @c <.
1406 *
1407 * See std::lexicographical_compare() for how the determination is made.
1408 */
1409 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1410 inline bool
1411 operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1412 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1413 { return __x._M_t < __y._M_t; }
1414
1415 /// Based on operator==
1416 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1417 inline bool
1418 operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1419 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1420 { return !(__x == __y); }
1421
1422 /// Based on operator<
1423 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1424 inline bool
1425 operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1426 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1427 { return __y < __x; }
1428
1429 /// Based on operator<
1430 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1431 inline bool
1432 operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1433 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1434 { return !(__y < __x); }
1435
1436 /// Based on operator<
1437 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1438 inline bool
1439 operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1440 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1441 { return !(__x < __y); }
1442
1443 /// See std::map::swap().
1444 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1445 inline void
1446 swap(map<_Key, _Tp, _Compare, _Alloc>& __x,
1447 map<_Key, _Tp, _Compare, _Alloc>& __y)
1448 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1449 { __x.swap(__y); }
1450
1451_GLIBCXX_END_NAMESPACE_CONTAINER
1452
1453#if __cplusplus > 201402L
1454_GLIBCXX_BEGIN_NAMESPACE_VERSION
1455 // Allow std::map access to internals of compatible maps.
1456 template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1457 typename _Cmp2>
1458 struct
1459 _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
1460 _Cmp2>
1461 {
1462 private:
1463 friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
1464
1465 static auto&
1466 _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1467 { return __map._M_t; }
1468
1469 static auto&
1470 _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1471 { return __map._M_t; }
1472 };
1473_GLIBCXX_END_NAMESPACE_VERSION
1474#endif // C++17
1475
1476} // namespace std
1477
1478#endif /* _STL_MAP_H */
1479