1// -*- C++ -*-
2//===------------------------ type_traits ---------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_TYPE_TRAITS
12#define _LIBCPP_TYPE_TRAITS
13
14/*
15    type_traits synopsis
16
17namespace std
18{
19
20    // helper class:
21    template <class T, T v> struct integral_constant;
22    typedef integral_constant<bool, true>  true_type;   // C++11
23    typedef integral_constant<bool, false> false_type;  // C++11
24
25    template <bool B>                                   // C++14
26    using bool_constant = integral_constant<bool, B>;   // C++14
27    typedef bool_constant<true> true_type;              // C++14
28    typedef bool_constant<false> false_type;            // C++14
29
30    // helper traits
31    template <bool, class T = void> struct enable_if;
32    template <bool, class T, class F> struct conditional;
33
34    // Primary classification traits:
35    template <class T> struct is_void;
36    template <class T> struct is_null_pointer;  // C++14
37    template <class T> struct is_integral;
38    template <class T> struct is_floating_point;
39    template <class T> struct is_array;
40    template <class T> struct is_pointer;
41    template <class T> struct is_lvalue_reference;
42    template <class T> struct is_rvalue_reference;
43    template <class T> struct is_member_object_pointer;
44    template <class T> struct is_member_function_pointer;
45    template <class T> struct is_enum;
46    template <class T> struct is_union;
47    template <class T> struct is_class;
48    template <class T> struct is_function;
49
50    // Secondary classification traits:
51    template <class T> struct is_reference;
52    template <class T> struct is_arithmetic;
53    template <class T> struct is_fundamental;
54    template <class T> struct is_member_pointer;
55    template <class T> struct is_scalar;
56    template <class T> struct is_object;
57    template <class T> struct is_compound;
58
59    // Const-volatile properties and transformations:
60    template <class T> struct is_const;
61    template <class T> struct is_volatile;
62    template <class T> struct remove_const;
63    template <class T> struct remove_volatile;
64    template <class T> struct remove_cv;
65    template <class T> struct add_const;
66    template <class T> struct add_volatile;
67    template <class T> struct add_cv;
68
69    // Reference transformations:
70    template <class T> struct remove_reference;
71    template <class T> struct add_lvalue_reference;
72    template <class T> struct add_rvalue_reference;
73
74    // Pointer transformations:
75    template <class T> struct remove_pointer;
76    template <class T> struct add_pointer;
77
78    // Integral properties:
79    template <class T> struct is_signed;
80    template <class T> struct is_unsigned;
81    template <class T> struct make_signed;
82    template <class T> struct make_unsigned;
83
84    // Array properties and transformations:
85    template <class T> struct rank;
86    template <class T, unsigned I = 0> struct extent;
87    template <class T> struct remove_extent;
88    template <class T> struct remove_all_extents;
89
90    // Member introspection:
91    template <class T> struct is_pod;
92    template <class T> struct is_trivial;
93    template <class T> struct is_trivially_copyable;
94    template <class T> struct is_standard_layout;
95    template <class T> struct is_literal_type;
96    template <class T> struct is_empty;
97    template <class T> struct is_polymorphic;
98    template <class T> struct is_abstract;
99    template <class T> struct is_final; // C++14
100
101    template <class T, class... Args> struct is_constructible;
102    template <class T>                struct is_default_constructible;
103    template <class T>                struct is_copy_constructible;
104    template <class T>                struct is_move_constructible;
105    template <class T, class U>       struct is_assignable;
106    template <class T>                struct is_copy_assignable;
107    template <class T>                struct is_move_assignable;
108    template <class T, class U>       struct is_swappable_with;       // C++17
109    template <class T>                struct is_swappable;            // C++17
110    template <class T>                struct is_destructible;
111
112    template <class T, class... Args> struct is_trivially_constructible;
113    template <class T>                struct is_trivially_default_constructible;
114    template <class T>                struct is_trivially_copy_constructible;
115    template <class T>                struct is_trivially_move_constructible;
116    template <class T, class U>       struct is_trivially_assignable;
117    template <class T>                struct is_trivially_copy_assignable;
118    template <class T>                struct is_trivially_move_assignable;
119    template <class T>                struct is_trivially_destructible;
120
121    template <class T, class... Args> struct is_nothrow_constructible;
122    template <class T>                struct is_nothrow_default_constructible;
123    template <class T>                struct is_nothrow_copy_constructible;
124    template <class T>                struct is_nothrow_move_constructible;
125    template <class T, class U>       struct is_nothrow_assignable;
126    template <class T>                struct is_nothrow_copy_assignable;
127    template <class T>                struct is_nothrow_move_assignable;
128    template <class T, class U>       struct is_nothrow_swappable_with; // C++17
129    template <class T>                struct is_nothrow_swappable;      // C++17
130    template <class T>                struct is_nothrow_destructible;
131
132    template <class T> struct has_virtual_destructor;
133
134    // Relationships between types:
135    template <class T, class U> struct is_same;
136    template <class Base, class Derived> struct is_base_of;
137    template <class From, class To> struct is_convertible;
138
139    template <class, class R = void> struct is_callable; // not defined
140    template <class Fn, class... ArgTypes, class R>
141      struct is_callable<Fn(ArgTypes...), R>;
142
143    template <class, class R = void> struct is_nothrow_callable; // not defined
144    template <class Fn, class... ArgTypes, class R>
145      struct is_nothrow_callable<Fn(ArgTypes...), R>;
146
147    // Alignment properties and transformations:
148    template <class T> struct alignment_of;
149    template <size_t Len, size_t Align = most_stringent_alignment_requirement>
150        struct aligned_storage;
151    template <size_t Len, class... Types> struct aligned_union;
152
153    template <class T> struct decay;
154    template <class... T> struct common_type;
155    template <class T> struct underlying_type;
156    template <class> class result_of; // undefined
157    template <class Fn, class... ArgTypes> class result_of<Fn(ArgTypes...)>;
158
159    // const-volatile modifications:
160    template <class T>
161      using remove_const_t    = typename remove_const<T>::type;  // C++14
162    template <class T>
163      using remove_volatile_t = typename remove_volatile<T>::type;  // C++14
164    template <class T>
165      using remove_cv_t       = typename remove_cv<T>::type;  // C++14
166    template <class T>
167      using add_const_t       = typename add_const<T>::type;  // C++14
168    template <class T>
169      using add_volatile_t    = typename add_volatile<T>::type;  // C++14
170    template <class T>
171      using add_cv_t          = typename add_cv<T>::type;  // C++14
172
173    // reference modifications:
174    template <class T>
175      using remove_reference_t     = typename remove_reference<T>::type;  // C++14
176    template <class T>
177      using add_lvalue_reference_t = typename add_lvalue_reference<T>::type;  // C++14
178    template <class T>
179      using add_rvalue_reference_t = typename add_rvalue_reference<T>::type;  // C++14
180
181    // sign modifications:
182    template <class T>
183      using make_signed_t   = typename make_signed<T>::type;  // C++14
184    template <class T>
185      using make_unsigned_t = typename make_unsigned<T>::type;  // C++14
186
187    // array modifications:
188    template <class T>
189      using remove_extent_t      = typename remove_extent<T>::type;  // C++14
190    template <class T>
191      using remove_all_extents_t = typename remove_all_extents<T>::type;  // C++14
192
193    // pointer modifications:
194    template <class T>
195      using remove_pointer_t = typename remove_pointer<T>::type;  // C++14
196    template <class T>
197      using add_pointer_t    = typename add_pointer<T>::type;  // C++14
198
199    // other transformations:
200    template <size_t Len, std::size_t Align=default-alignment>
201      using aligned_storage_t = typename aligned_storage<Len,Align>::type;  // C++14
202    template <std::size_t Len, class... Types>
203      using aligned_union_t   = typename aligned_union<Len,Types...>::type;  // C++14
204    template <class T>
205      using decay_t           = typename decay<T>::type;  // C++14
206    template <bool b, class T=void>
207      using enable_if_t       = typename enable_if<b,T>::type;  // C++14
208    template <bool b, class T, class F>
209      using conditional_t     = typename conditional<b,T,F>::type;  // C++14
210    template <class... T>
211      using common_type_t     = typename common_type<T...>::type;  // C++14
212    template <class T>
213      using underlying_type_t = typename underlying_type<T>::type;  // C++14
214    template <class F, class... ArgTypes>
215      using result_of_t       = typename result_of<F(ArgTypes...)>::type;  // C++14
216
217    template <class...>
218      using void_t = void;   // C++17
219
220      // See C++14 20.10.4.1, primary type categories
221      template <class T> constexpr bool is_void_v
222        = is_void<T>::value;                                             // C++17
223      template <class T> constexpr bool is_null_pointer_v
224        = is_null_pointer<T>::value;                                     // C++17
225      template <class T> constexpr bool is_integral_v
226        = is_integral<T>::value;                                         // C++17
227      template <class T> constexpr bool is_floating_point_v
228        = is_floating_point<T>::value;                                   // C++17
229      template <class T> constexpr bool is_array_v
230        = is_array<T>::value;                                            // C++17
231      template <class T> constexpr bool is_pointer_v
232        = is_pointer<T>::value;                                          // C++17
233      template <class T> constexpr bool is_lvalue_reference_v
234        = is_lvalue_reference<T>::value;                                 // C++17
235      template <class T> constexpr bool is_rvalue_reference_v
236        = is_rvalue_reference<T>::value;                                 // C++17
237      template <class T> constexpr bool is_member_object_pointer_v
238        = is_member_object_pointer<T>::value;                            // C++17
239      template <class T> constexpr bool is_member_function_pointer_v
240        = is_member_function_pointer<T>::value;                          // C++17
241      template <class T> constexpr bool is_enum_v
242        = is_enum<T>::value;                                             // C++17
243      template <class T> constexpr bool is_union_v
244        = is_union<T>::value;                                            // C++17
245      template <class T> constexpr bool is_class_v
246        = is_class<T>::value;                                            // C++17
247      template <class T> constexpr bool is_function_v
248        = is_function<T>::value;                                         // C++17
249
250      // See C++14 20.10.4.2, composite type categories
251      template <class T> constexpr bool is_reference_v
252        = is_reference<T>::value;                                        // C++17
253      template <class T> constexpr bool is_arithmetic_v
254        = is_arithmetic<T>::value;                                       // C++17
255      template <class T> constexpr bool is_fundamental_v
256        = is_fundamental<T>::value;                                      // C++17
257      template <class T> constexpr bool is_object_v
258        = is_object<T>::value;                                           // C++17
259      template <class T> constexpr bool is_scalar_v
260        = is_scalar<T>::value;                                           // C++17
261      template <class T> constexpr bool is_compound_v
262        = is_compound<T>::value;                                         // C++17
263      template <class T> constexpr bool is_member_pointer_v
264        = is_member_pointer<T>::value;                                   // C++17
265
266      // See C++14 20.10.4.3, type properties
267      template <class T> constexpr bool is_const_v
268        = is_const<T>::value;                                            // C++17
269      template <class T> constexpr bool is_volatile_v
270        = is_volatile<T>::value;                                         // C++17
271      template <class T> constexpr bool is_trivial_v
272        = is_trivial<T>::value;                                          // C++17
273      template <class T> constexpr bool is_trivially_copyable_v
274        = is_trivially_copyable<T>::value;                               // C++17
275      template <class T> constexpr bool is_standard_layout_v
276        = is_standard_layout<T>::value;                                  // C++17
277      template <class T> constexpr bool is_pod_v
278        = is_pod<T>::value;                                              // C++17
279      template <class T> constexpr bool is_literal_type_v
280        = is_literal_type<T>::value;                                     // C++17
281      template <class T> constexpr bool is_empty_v
282        = is_empty<T>::value;                                            // C++17
283      template <class T> constexpr bool is_polymorphic_v
284        = is_polymorphic<T>::value;                                      // C++17
285      template <class T> constexpr bool is_abstract_v
286        = is_abstract<T>::value;                                         // C++17
287      template <class T> constexpr bool is_final_v
288        = is_final<T>::value;                                            // C++17
289      template <class T> constexpr bool is_signed_v
290        = is_signed<T>::value;                                           // C++17
291      template <class T> constexpr bool is_unsigned_v
292        = is_unsigned<T>::value;                                         // C++17
293      template <class T, class... Args> constexpr bool is_constructible_v
294        = is_constructible<T, Args...>::value;                           // C++17
295      template <class T> constexpr bool is_default_constructible_v
296        = is_default_constructible<T>::value;                            // C++17
297      template <class T> constexpr bool is_copy_constructible_v
298        = is_copy_constructible<T>::value;                               // C++17
299      template <class T> constexpr bool is_move_constructible_v
300        = is_move_constructible<T>::value;                               // C++17
301      template <class T, class U> constexpr bool is_assignable_v
302        = is_assignable<T, U>::value;                                    // C++17
303      template <class T> constexpr bool is_copy_assignable_v
304        = is_copy_assignable<T>::value;                                  // C++17
305      template <class T> constexpr bool is_move_assignable_v
306        = is_move_assignable<T>::value;                                  // C++17
307      template <class T, class U> constexpr bool is_swappable_with_v
308        = is_swappable_with<T, U>::value;                                // C++17
309      template <class T> constexpr bool is_swappable_v
310        = is_swappable<T>::value;                                        // C++17
311      template <class T> constexpr bool is_destructible_v
312        = is_destructible<T>::value;                                     // C++17
313      template <class T, class... Args> constexpr bool is_trivially_constructible_v
314        = is_trivially_constructible<T, Args...>::value;                 // C++17
315      template <class T> constexpr bool is_trivially_default_constructible_v
316        = is_trivially_default_constructible<T>::value;                  // C++17
317      template <class T> constexpr bool is_trivially_copy_constructible_v
318        = is_trivially_copy_constructible<T>::value;                     // C++17
319      template <class T> constexpr bool is_trivially_move_constructible_v
320        = is_trivially_move_constructible<T>::value;                     // C++17
321      template <class T, class U> constexpr bool is_trivially_assignable_v
322        = is_trivially_assignable<T, U>::value;                          // C++17
323      template <class T> constexpr bool is_trivially_copy_assignable_v
324        = is_trivially_copy_assignable<T>::value;                        // C++17
325      template <class T> constexpr bool is_trivially_move_assignable_v
326        = is_trivially_move_assignable<T>::value;                        // C++17
327      template <class T> constexpr bool is_trivially_destructible_v
328        = is_trivially_destructible<T>::value;                           // C++17
329      template <class T, class... Args> constexpr bool is_nothrow_constructible_v
330        = is_nothrow_constructible<T, Args...>::value;                   // C++17
331      template <class T> constexpr bool is_nothrow_default_constructible_v
332        = is_nothrow_default_constructible<T>::value;                    // C++17
333      template <class T> constexpr bool is_nothrow_copy_constructible_v
334        = is_nothrow_copy_constructible<T>::value;                       // C++17
335      template <class T> constexpr bool is_nothrow_move_constructible_v
336        = is_nothrow_move_constructible<T>::value;                       // C++17
337      template <class T, class U> constexpr bool is_nothrow_assignable_v
338        = is_nothrow_assignable<T, U>::value;                            // C++17
339      template <class T> constexpr bool is_nothrow_copy_assignable_v
340        = is_nothrow_copy_assignable<T>::value;                          // C++17
341      template <class T> constexpr bool is_nothrow_move_assignable_v
342        = is_nothrow_move_assignable<T>::value;                          // C++17
343      template <class T, class U> constexpr bool is_nothrow_swappable_with_v
344        = is_nothrow_swappable_with<T, U>::value;                       // C++17
345      template <class T> constexpr bool is_nothrow_swappable_v
346        = is_nothrow_swappable<T>::value;                               // C++17
347      template <class T> constexpr bool is_nothrow_destructible_v
348        = is_nothrow_destructible<T>::value;                             // C++17
349      template <class T> constexpr bool has_virtual_destructor_v
350        = has_virtual_destructor<T>::value;                              // C++17
351
352      // See C++14 20.10.5, type property queries
353      template <class T> constexpr size_t alignment_of_v
354        = alignment_of<T>::value;                                        // C++17
355      template <class T> constexpr size_t rank_v
356        = rank<T>::value;                                                // C++17
357      template <class T, unsigned I = 0> constexpr size_t extent_v
358        = extent<T, I>::value;                                           // C++17
359
360      // See C++14 20.10.6, type relations
361      template <class T, class U> constexpr bool is_same_v
362        = is_same<T, U>::value;                                          // C++17
363      template <class Base, class Derived> constexpr bool is_base_of_v
364        = is_base_of<Base, Derived>::value;                              // C++17
365      template <class From, class To> constexpr bool is_convertible_v
366        = is_convertible<From, To>::value;                               // C++17
367      template <class T, class R = void> constexpr bool is_callable_v
368        = is_callable<T, R>::value;                                      // C++17
369      template <class T, class R = void> constexpr bool is_nothrow_callable_v
370        = is_nothrow_callable<T, R>::value;                              // C++17
371
372      // [meta.logical], logical operator traits:
373      template<class... B> struct conjunction;                           // C++17
374      template<class... B>
375        constexpr bool conjunction_v = conjunction<B...>::value;         // C++17
376      template<class... B> struct disjunction;                           // C++17
377      template<class... B>
378        constexpr bool disjunction_v = disjunction<B...>::value;         // C++17
379      template<class B> struct negation;                                 // C++17
380      template<class B>
381        constexpr bool negation_v = negation<B>::value;                  // C++17
382
383}
384
385*/
386#include <__config>
387#include <cstddef>
388
389#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
390#pragma GCC system_header
391#endif
392
393_LIBCPP_BEGIN_NAMESPACE_STD
394
395template <class _T1, class _T2> struct _LIBCPP_TEMPLATE_VIS pair;
396template <class _Tp> class _LIBCPP_TEMPLATE_VIS reference_wrapper;
397template <class _Tp> struct _LIBCPP_TEMPLATE_VIS hash;
398
399template <class>
400struct __void_t { typedef void type; };
401
402template <class _Tp>
403struct __identity { typedef _Tp type; };
404
405template <class _Tp, bool>
406struct _LIBCPP_TEMPLATE_VIS __dependent_type : public _Tp {};
407
408template <bool _Bp, class _If, class _Then>
409    struct _LIBCPP_TEMPLATE_VIS conditional {typedef _If type;};
410template <class _If, class _Then>
411    struct _LIBCPP_TEMPLATE_VIS conditional<false, _If, _Then> {typedef _Then type;};
412
413#if _LIBCPP_STD_VER > 11
414template <bool _Bp, class _If, class _Then> using conditional_t = typename conditional<_Bp, _If, _Then>::type;
415#endif
416
417template <bool, class _Tp> struct _LIBCPP_TEMPLATE_VIS __lazy_enable_if {};
418template <class _Tp> struct _LIBCPP_TEMPLATE_VIS __lazy_enable_if<true, _Tp> {typedef typename _Tp::type type;};
419
420template <bool, class _Tp = void> struct _LIBCPP_TEMPLATE_VIS enable_if {};
421template <class _Tp> struct _LIBCPP_TEMPLATE_VIS enable_if<true, _Tp> {typedef _Tp type;};
422
423#if _LIBCPP_STD_VER > 11
424template <bool _Bp, class _Tp = void> using enable_if_t = typename enable_if<_Bp, _Tp>::type;
425#endif
426
427// addressof
428#ifndef _LIBCPP_HAS_NO_BUILTIN_ADDRESSOF
429
430template <class _Tp>
431inline _LIBCPP_CONSTEXPR_AFTER_CXX14
432_LIBCPP_NO_CFI _LIBCPP_INLINE_VISIBILITY
433_Tp*
434addressof(_Tp& __x) _NOEXCEPT
435{
436    return __builtin_addressof(__x);
437}
438
439#else
440
441template <class _Tp>
442inline _LIBCPP_NO_CFI _LIBCPP_INLINE_VISIBILITY
443_Tp*
444addressof(_Tp& __x) _NOEXCEPT
445{
446  return reinterpret_cast<_Tp *>(
447      const_cast<char *>(&reinterpret_cast<const volatile char &>(__x)));
448}
449
450#endif // _LIBCPP_HAS_NO_BUILTIN_ADDRESSOF
451
452#if defined(_LIBCPP_HAS_OBJC_ARC) && !defined(_LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF)
453// Objective-C++ Automatic Reference Counting uses qualified pointers
454// that require special addressof() signatures. When
455// _LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF is defined, the compiler
456// itself is providing these definitions. Otherwise, we provide them.
457template <class _Tp>
458inline _LIBCPP_INLINE_VISIBILITY
459__strong _Tp*
460addressof(__strong _Tp& __x) _NOEXCEPT
461{
462  return &__x;
463}
464
465#ifdef _LIBCPP_HAS_OBJC_ARC_WEAK
466template <class _Tp>
467inline _LIBCPP_INLINE_VISIBILITY
468__weak _Tp*
469addressof(__weak _Tp& __x) _NOEXCEPT
470{
471  return &__x;
472}
473#endif
474
475template <class _Tp>
476inline _LIBCPP_INLINE_VISIBILITY
477__autoreleasing _Tp*
478addressof(__autoreleasing _Tp& __x) _NOEXCEPT
479{
480  return &__x;
481}
482
483template <class _Tp>
484inline _LIBCPP_INLINE_VISIBILITY
485__unsafe_unretained _Tp*
486addressof(__unsafe_unretained _Tp& __x) _NOEXCEPT
487{
488  return &__x;
489}
490#endif
491
492#if !defined(_LIBCPP_CXX03_LANG)
493template <class _Tp> _Tp* addressof(const _Tp&&) noexcept = delete;
494#endif
495
496struct __two {char __lx[2];};
497
498// helper class:
499
500template <class _Tp, _Tp __v>
501struct _LIBCPP_TEMPLATE_VIS integral_constant
502{
503    static _LIBCPP_CONSTEXPR const _Tp      value = __v;
504    typedef _Tp               value_type;
505    typedef integral_constant type;
506    _LIBCPP_INLINE_VISIBILITY
507        _LIBCPP_CONSTEXPR operator value_type() const _NOEXCEPT {return value;}
508#if _LIBCPP_STD_VER > 11
509    _LIBCPP_INLINE_VISIBILITY
510         constexpr value_type operator ()() const _NOEXCEPT {return value;}
511#endif
512};
513
514template <class _Tp, _Tp __v>
515_LIBCPP_CONSTEXPR const _Tp integral_constant<_Tp, __v>::value;
516
517#if _LIBCPP_STD_VER > 14
518template <bool __b>
519using bool_constant = integral_constant<bool, __b>;
520#define _LIBCPP_BOOL_CONSTANT(__b) bool_constant<(__b)>
521#else
522#define _LIBCPP_BOOL_CONSTANT(__b) integral_constant<bool,(__b)>
523#endif
524
525typedef _LIBCPP_BOOL_CONSTANT(true)  true_type;
526typedef _LIBCPP_BOOL_CONSTANT(false) false_type;
527
528#if !defined(_LIBCPP_CXX03_LANG)
529
530// __lazy_and
531
532template <bool _Last, class ..._Preds>
533struct __lazy_and_impl;
534
535template <class ..._Preds>
536struct __lazy_and_impl<false, _Preds...> : false_type {};
537
538template <>
539struct __lazy_and_impl<true> : true_type {};
540
541template <class _Pred>
542struct __lazy_and_impl<true, _Pred> : integral_constant<bool, _Pred::type::value> {};
543
544template <class _Hp, class ..._Tp>
545struct __lazy_and_impl<true, _Hp, _Tp...> : __lazy_and_impl<_Hp::type::value, _Tp...> {};
546
547template <class _P1, class ..._Pr>
548struct __lazy_and : __lazy_and_impl<_P1::type::value, _Pr...> {};
549
550// __lazy_or
551
552template <bool _List, class ..._Preds>
553struct __lazy_or_impl;
554
555template <class ..._Preds>
556struct __lazy_or_impl<true, _Preds...> : true_type {};
557
558template <>
559struct __lazy_or_impl<false> : false_type {};
560
561template <class _Hp, class ..._Tp>
562struct __lazy_or_impl<false, _Hp, _Tp...>
563        : __lazy_or_impl<_Hp::type::value, _Tp...> {};
564
565template <class _P1, class ..._Pr>
566struct __lazy_or : __lazy_or_impl<_P1::type::value, _Pr...> {};
567
568// __lazy_not
569
570template <class _Pred>
571struct __lazy_not : integral_constant<bool, !_Pred::type::value> {};
572
573// __and_
574template<class...> struct __and_;
575template<> struct __and_<> : true_type {};
576
577template<class _B0> struct __and_<_B0> : _B0 {};
578
579template<class _B0, class _B1>
580struct __and_<_B0, _B1> : conditional<_B0::value, _B1, _B0>::type {};
581
582template<class _B0, class _B1, class _B2, class... _Bn>
583struct __and_<_B0, _B1, _B2, _Bn...>
584        : conditional<_B0::value, __and_<_B1, _B2, _Bn...>, _B0>::type {};
585
586// __or_
587template<class...> struct __or_;
588template<> struct __or_<> : false_type {};
589
590template<class _B0> struct __or_<_B0> : _B0 {};
591
592template<class _B0, class _B1>
593struct __or_<_B0, _B1> : conditional<_B0::value, _B0, _B1>::type {};
594
595template<class _B0, class _B1, class _B2, class... _Bn>
596struct __or_<_B0, _B1, _B2, _Bn...>
597        : conditional<_B0::value, _B0, __or_<_B1, _B2, _Bn...> >::type {};
598
599// __not_
600template<class _Tp>
601struct __not_ : conditional<_Tp::value, false_type, true_type>::type {};
602
603#endif // !defined(_LIBCPP_CXX03_LANG)
604
605// is_const
606
607template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_const            : public false_type {};
608template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_const<_Tp const> : public true_type {};
609
610#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
611template <class _Tp> _LIBCPP_CONSTEXPR bool is_const_v
612    = is_const<_Tp>::value;
613#endif
614
615// is_volatile
616
617template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_volatile               : public false_type {};
618template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_volatile<_Tp volatile> : public true_type {};
619
620#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
621template <class _Tp> _LIBCPP_CONSTEXPR bool is_volatile_v
622    = is_volatile<_Tp>::value;
623#endif
624
625// remove_const
626
627template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_const            {typedef _Tp type;};
628template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_const<const _Tp> {typedef _Tp type;};
629#if _LIBCPP_STD_VER > 11
630template <class _Tp> using remove_const_t = typename remove_const<_Tp>::type;
631#endif
632
633// remove_volatile
634
635template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_volatile               {typedef _Tp type;};
636template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_volatile<volatile _Tp> {typedef _Tp type;};
637#if _LIBCPP_STD_VER > 11
638template <class _Tp> using remove_volatile_t = typename remove_volatile<_Tp>::type;
639#endif
640
641// remove_cv
642
643template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_cv
644{typedef typename remove_volatile<typename remove_const<_Tp>::type>::type type;};
645#if _LIBCPP_STD_VER > 11
646template <class _Tp> using remove_cv_t = typename remove_cv<_Tp>::type;
647#endif
648
649// is_void
650
651template <class _Tp> struct __libcpp_is_void       : public false_type {};
652template <>          struct __libcpp_is_void<void> : public true_type {};
653
654template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_void
655    : public __libcpp_is_void<typename remove_cv<_Tp>::type> {};
656
657#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
658template <class _Tp> _LIBCPP_CONSTEXPR bool is_void_v
659    = is_void<_Tp>::value;
660#endif
661
662// __is_nullptr_t
663
664template <class _Tp> struct __is_nullptr_t_impl       : public false_type {};
665template <>          struct __is_nullptr_t_impl<nullptr_t> : public true_type {};
666
667template <class _Tp> struct _LIBCPP_TEMPLATE_VIS __is_nullptr_t
668    : public __is_nullptr_t_impl<typename remove_cv<_Tp>::type> {};
669
670#if _LIBCPP_STD_VER > 11
671template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_null_pointer
672    : public __is_nullptr_t_impl<typename remove_cv<_Tp>::type> {};
673
674#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
675template <class _Tp> _LIBCPP_CONSTEXPR bool is_null_pointer_v
676    = is_null_pointer<_Tp>::value;
677#endif
678#endif
679
680// is_integral
681
682template <class _Tp> struct __libcpp_is_integral                     : public false_type {};
683template <>          struct __libcpp_is_integral<bool>               : public true_type {};
684template <>          struct __libcpp_is_integral<char>               : public true_type {};
685template <>          struct __libcpp_is_integral<signed char>        : public true_type {};
686template <>          struct __libcpp_is_integral<unsigned char>      : public true_type {};
687template <>          struct __libcpp_is_integral<wchar_t>            : public true_type {};
688#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
689template <>          struct __libcpp_is_integral<char16_t>           : public true_type {};
690template <>          struct __libcpp_is_integral<char32_t>           : public true_type {};
691#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
692template <>          struct __libcpp_is_integral<short>              : public true_type {};
693template <>          struct __libcpp_is_integral<unsigned short>     : public true_type {};
694template <>          struct __libcpp_is_integral<int>                : public true_type {};
695template <>          struct __libcpp_is_integral<unsigned int>       : public true_type {};
696template <>          struct __libcpp_is_integral<long>               : public true_type {};
697template <>          struct __libcpp_is_integral<unsigned long>      : public true_type {};
698template <>          struct __libcpp_is_integral<long long>          : public true_type {};
699template <>          struct __libcpp_is_integral<unsigned long long> : public true_type {};
700#ifndef _LIBCPP_HAS_NO_INT128
701template <>          struct __libcpp_is_integral<__int128_t>         : public true_type {};
702template <>          struct __libcpp_is_integral<__uint128_t>        : public true_type {};
703#endif
704
705template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_integral
706    : public __libcpp_is_integral<typename remove_cv<_Tp>::type> {};
707
708#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
709template <class _Tp> _LIBCPP_CONSTEXPR bool is_integral_v
710    = is_integral<_Tp>::value;
711#endif
712
713// is_floating_point
714
715template <class _Tp> struct __libcpp_is_floating_point              : public false_type {};
716template <>          struct __libcpp_is_floating_point<float>       : public true_type {};
717template <>          struct __libcpp_is_floating_point<double>      : public true_type {};
718template <>          struct __libcpp_is_floating_point<long double> : public true_type {};
719
720template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_floating_point
721    : public __libcpp_is_floating_point<typename remove_cv<_Tp>::type> {};
722
723#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
724template <class _Tp> _LIBCPP_CONSTEXPR bool is_floating_point_v
725    = is_floating_point<_Tp>::value;
726#endif
727
728// is_array
729
730template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_array
731    : public false_type {};
732template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_array<_Tp[]>
733    : public true_type {};
734template <class _Tp, size_t _Np> struct _LIBCPP_TEMPLATE_VIS is_array<_Tp[_Np]>
735    : public true_type {};
736
737#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
738template <class _Tp> _LIBCPP_CONSTEXPR bool is_array_v
739    = is_array<_Tp>::value;
740#endif
741
742// is_pointer
743
744template <class _Tp> struct __libcpp_is_pointer       : public false_type {};
745template <class _Tp> struct __libcpp_is_pointer<_Tp*> : public true_type {};
746
747template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_pointer
748    : public __libcpp_is_pointer<typename remove_cv<_Tp>::type> {};
749
750#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
751template <class _Tp> _LIBCPP_CONSTEXPR bool is_pointer_v
752    = is_pointer<_Tp>::value;
753#endif
754
755// is_reference
756
757template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_lvalue_reference       : public false_type {};
758template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_lvalue_reference<_Tp&> : public true_type {};
759
760template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_rvalue_reference        : public false_type {};
761#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
762template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_rvalue_reference<_Tp&&> : public true_type {};
763#endif
764
765template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_reference        : public false_type {};
766template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_reference<_Tp&>  : public true_type {};
767#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
768template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_reference<_Tp&&> : public true_type {};
769#endif
770
771#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
772template <class _Tp> _LIBCPP_CONSTEXPR bool is_reference_v
773    = is_reference<_Tp>::value;
774
775template <class _Tp> _LIBCPP_CONSTEXPR bool is_lvalue_reference_v
776    = is_lvalue_reference<_Tp>::value;
777
778template <class _Tp> _LIBCPP_CONSTEXPR bool is_rvalue_reference_v
779    = is_rvalue_reference<_Tp>::value;
780#endif
781// is_union
782
783#if __has_feature(is_union) || (_GNUC_VER >= 403)
784
785template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_union
786    : public integral_constant<bool, __is_union(_Tp)> {};
787
788#else
789
790template <class _Tp> struct __libcpp_union : public false_type {};
791template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_union
792    : public __libcpp_union<typename remove_cv<_Tp>::type> {};
793
794#endif
795
796#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
797template <class _Tp> _LIBCPP_CONSTEXPR bool is_union_v
798    = is_union<_Tp>::value;
799#endif
800
801// is_class
802
803#if __has_feature(is_class) || (_GNUC_VER >= 403)
804
805template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_class
806    : public integral_constant<bool, __is_class(_Tp)> {};
807
808#else
809
810namespace __is_class_imp
811{
812template <class _Tp> char  __test(int _Tp::*);
813template <class _Tp> __two __test(...);
814}
815
816template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_class
817    : public integral_constant<bool, sizeof(__is_class_imp::__test<_Tp>(0)) == 1 && !is_union<_Tp>::value> {};
818
819#endif
820
821#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
822template <class _Tp> _LIBCPP_CONSTEXPR bool is_class_v
823    = is_class<_Tp>::value;
824#endif
825
826// is_same
827
828template <class _Tp, class _Up> struct _LIBCPP_TEMPLATE_VIS is_same           : public false_type {};
829template <class _Tp>            struct _LIBCPP_TEMPLATE_VIS is_same<_Tp, _Tp> : public true_type {};
830
831#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
832template <class _Tp, class _Up> _LIBCPP_CONSTEXPR bool is_same_v
833    = is_same<_Tp, _Up>::value;
834#endif
835
836// is_function
837
838namespace __libcpp_is_function_imp
839{
840struct __dummy_type {};
841template <class _Tp> char  __test(_Tp*);
842template <class _Tp> char __test(__dummy_type);
843template <class _Tp> __two __test(...);
844template <class _Tp> _Tp&  __source(int);
845template <class _Tp> __dummy_type __source(...);
846}
847
848template <class _Tp, bool = is_class<_Tp>::value ||
849                            is_union<_Tp>::value ||
850                            is_void<_Tp>::value  ||
851                            is_reference<_Tp>::value ||
852                            __is_nullptr_t<_Tp>::value >
853struct __libcpp_is_function
854    : public integral_constant<bool, sizeof(__libcpp_is_function_imp::__test<_Tp>(__libcpp_is_function_imp::__source<_Tp>(0))) == 1>
855    {};
856template <class _Tp> struct __libcpp_is_function<_Tp, true> : public false_type {};
857
858template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_function
859    : public __libcpp_is_function<_Tp> {};
860
861#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
862template <class _Tp> _LIBCPP_CONSTEXPR bool is_function_v
863    = is_function<_Tp>::value;
864#endif
865
866// is_member_function_pointer
867
868// template <class _Tp> struct            __libcpp_is_member_function_pointer             : public false_type {};
869// template <class _Tp, class _Up> struct __libcpp_is_member_function_pointer<_Tp _Up::*> : public is_function<_Tp> {};
870//
871
872template <class _MP, bool _IsMemberFunctionPtr, bool _IsMemberObjectPtr>
873struct __member_pointer_traits_imp
874{  // forward declaration; specializations later
875};
876
877
878template <class _Tp> struct __libcpp_is_member_function_pointer
879    : public false_type {};
880
881template <class _Ret, class _Class>
882struct __libcpp_is_member_function_pointer<_Ret _Class::*>
883    : public is_function<_Ret> {};
884
885template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_member_function_pointer
886    : public __libcpp_is_member_function_pointer<typename remove_cv<_Tp>::type>::type {};
887
888#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
889template <class _Tp> _LIBCPP_CONSTEXPR bool is_member_function_pointer_v
890    = is_member_function_pointer<_Tp>::value;
891#endif
892
893// is_member_pointer
894
895template <class _Tp>            struct __libcpp_is_member_pointer             : public false_type {};
896template <class _Tp, class _Up> struct __libcpp_is_member_pointer<_Tp _Up::*> : public true_type {};
897
898template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_member_pointer
899    : public __libcpp_is_member_pointer<typename remove_cv<_Tp>::type> {};
900
901#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
902template <class _Tp> _LIBCPP_CONSTEXPR bool is_member_pointer_v
903    = is_member_pointer<_Tp>::value;
904#endif
905
906// is_member_object_pointer
907
908template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_member_object_pointer
909    : public integral_constant<bool, is_member_pointer<_Tp>::value &&
910                                    !is_member_function_pointer<_Tp>::value> {};
911
912#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
913template <class _Tp> _LIBCPP_CONSTEXPR bool is_member_object_pointer_v
914    = is_member_object_pointer<_Tp>::value;
915#endif
916
917// is_enum
918
919#if __has_feature(is_enum) || (_GNUC_VER >= 403)
920
921template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_enum
922    : public integral_constant<bool, __is_enum(_Tp)> {};
923
924#else
925
926template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_enum
927    : public integral_constant<bool, !is_void<_Tp>::value             &&
928                                     !is_integral<_Tp>::value         &&
929                                     !is_floating_point<_Tp>::value   &&
930                                     !is_array<_Tp>::value            &&
931                                     !is_pointer<_Tp>::value          &&
932                                     !is_reference<_Tp>::value        &&
933                                     !is_member_pointer<_Tp>::value   &&
934                                     !is_union<_Tp>::value            &&
935                                     !is_class<_Tp>::value            &&
936                                     !is_function<_Tp>::value         > {};
937
938#endif
939
940#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
941template <class _Tp> _LIBCPP_CONSTEXPR bool is_enum_v
942    = is_enum<_Tp>::value;
943#endif
944
945// is_arithmetic
946
947template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_arithmetic
948    : public integral_constant<bool, is_integral<_Tp>::value      ||
949                                     is_floating_point<_Tp>::value> {};
950
951#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
952template <class _Tp> _LIBCPP_CONSTEXPR bool is_arithmetic_v
953    = is_arithmetic<_Tp>::value;
954#endif
955
956// is_fundamental
957
958template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_fundamental
959    : public integral_constant<bool, is_void<_Tp>::value        ||
960                                     __is_nullptr_t<_Tp>::value ||
961                                     is_arithmetic<_Tp>::value> {};
962
963#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
964template <class _Tp> _LIBCPP_CONSTEXPR bool is_fundamental_v
965    = is_fundamental<_Tp>::value;
966#endif
967
968// is_scalar
969
970template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_scalar
971    : public integral_constant<bool, is_arithmetic<_Tp>::value     ||
972                                     is_member_pointer<_Tp>::value ||
973                                     is_pointer<_Tp>::value        ||
974                                     __is_nullptr_t<_Tp>::value    ||
975                                     is_enum<_Tp>::value           > {};
976
977template <> struct _LIBCPP_TEMPLATE_VIS is_scalar<nullptr_t> : public true_type {};
978
979#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
980template <class _Tp> _LIBCPP_CONSTEXPR bool is_scalar_v
981    = is_scalar<_Tp>::value;
982#endif
983
984// is_object
985
986template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_object
987    : public integral_constant<bool, is_scalar<_Tp>::value ||
988                                     is_array<_Tp>::value  ||
989                                     is_union<_Tp>::value  ||
990                                     is_class<_Tp>::value  > {};
991
992#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
993template <class _Tp> _LIBCPP_CONSTEXPR bool is_object_v
994    = is_object<_Tp>::value;
995#endif
996
997// is_compound
998
999template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_compound
1000    : public integral_constant<bool, !is_fundamental<_Tp>::value> {};
1001
1002#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1003template <class _Tp> _LIBCPP_CONSTEXPR bool is_compound_v
1004    = is_compound<_Tp>::value;
1005#endif
1006
1007
1008// __is_referenceable  [defns.referenceable]
1009
1010struct __is_referenceable_impl {
1011    template <class _Tp> static _Tp& __test(int);
1012    template <class _Tp> static __two __test(...);
1013};
1014
1015template <class _Tp>
1016struct __is_referenceable : integral_constant<bool,
1017    !is_same<decltype(__is_referenceable_impl::__test<_Tp>(0)), __two>::value> {};
1018
1019
1020// add_const
1021
1022template <class _Tp, bool = is_reference<_Tp>::value ||
1023                            is_function<_Tp>::value  ||
1024                            is_const<_Tp>::value     >
1025struct __add_const             {typedef _Tp type;};
1026
1027template <class _Tp>
1028struct __add_const<_Tp, false> {typedef const _Tp type;};
1029
1030template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_const
1031    {typedef typename __add_const<_Tp>::type type;};
1032
1033#if _LIBCPP_STD_VER > 11
1034template <class _Tp> using add_const_t = typename add_const<_Tp>::type;
1035#endif
1036
1037// add_volatile
1038
1039template <class _Tp, bool = is_reference<_Tp>::value ||
1040                            is_function<_Tp>::value  ||
1041                            is_volatile<_Tp>::value  >
1042struct __add_volatile             {typedef _Tp type;};
1043
1044template <class _Tp>
1045struct __add_volatile<_Tp, false> {typedef volatile _Tp type;};
1046
1047template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_volatile
1048    {typedef typename __add_volatile<_Tp>::type type;};
1049
1050#if _LIBCPP_STD_VER > 11
1051template <class _Tp> using add_volatile_t = typename add_volatile<_Tp>::type;
1052#endif
1053
1054// add_cv
1055
1056template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_cv
1057    {typedef typename add_const<typename add_volatile<_Tp>::type>::type type;};
1058
1059#if _LIBCPP_STD_VER > 11
1060template <class _Tp> using add_cv_t = typename add_cv<_Tp>::type;
1061#endif
1062
1063// remove_reference
1064
1065template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_reference        {typedef _Tp type;};
1066template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_reference<_Tp&>  {typedef _Tp type;};
1067#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1068template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_reference<_Tp&&> {typedef _Tp type;};
1069#endif
1070
1071#if _LIBCPP_STD_VER > 11
1072template <class _Tp> using remove_reference_t = typename remove_reference<_Tp>::type;
1073#endif
1074
1075// add_lvalue_reference
1076
1077template <class _Tp, bool = __is_referenceable<_Tp>::value> struct __add_lvalue_reference_impl            { typedef _Tp  type; };
1078template <class _Tp                                       > struct __add_lvalue_reference_impl<_Tp, true> { typedef _Tp& type; };
1079
1080template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_lvalue_reference
1081{typedef typename __add_lvalue_reference_impl<_Tp>::type type;};
1082
1083#if _LIBCPP_STD_VER > 11
1084template <class _Tp> using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type;
1085#endif
1086
1087#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1088
1089template <class _Tp, bool = __is_referenceable<_Tp>::value> struct __add_rvalue_reference_impl            { typedef _Tp   type; };
1090template <class _Tp                                       > struct __add_rvalue_reference_impl<_Tp, true> { typedef _Tp&& type; };
1091
1092template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_rvalue_reference
1093{typedef typename __add_rvalue_reference_impl<_Tp>::type type;};
1094
1095#if _LIBCPP_STD_VER > 11
1096template <class _Tp> using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type;
1097#endif
1098
1099#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1100
1101#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1102
1103template <class _Tp> _Tp&& __declval(int);
1104template <class _Tp> _Tp   __declval(long);
1105
1106template <class _Tp>
1107decltype(_VSTD::__declval<_Tp>(0))
1108declval() _NOEXCEPT;
1109
1110#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1111
1112template <class _Tp>
1113typename add_lvalue_reference<_Tp>::type
1114declval();
1115
1116#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1117
1118// __uncvref
1119
1120template <class _Tp>
1121struct __uncvref  {
1122    typedef typename remove_cv<typename remove_reference<_Tp>::type>::type type;
1123};
1124
1125template <class _Tp>
1126struct __unconstref {
1127    typedef typename remove_const<typename remove_reference<_Tp>::type>::type type;
1128};
1129
1130#ifndef _LIBCPP_CXX03_LANG
1131template <class _Tp>
1132using __uncvref_t = typename __uncvref<_Tp>::type;
1133#endif
1134
1135// __is_same_uncvref
1136
1137template <class _Tp, class _Up>
1138struct __is_same_uncvref : is_same<typename __uncvref<_Tp>::type,
1139                                   typename __uncvref<_Up>::type> {};
1140
1141struct __any
1142{
1143    __any(...);
1144};
1145
1146// remove_pointer
1147
1148template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer                      {typedef _Tp type;};
1149template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp*>                {typedef _Tp type;};
1150template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* const>          {typedef _Tp type;};
1151template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* volatile>       {typedef _Tp type;};
1152template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_pointer<_Tp* const volatile> {typedef _Tp type;};
1153
1154#if _LIBCPP_STD_VER > 11
1155template <class _Tp> using remove_pointer_t = typename remove_pointer<_Tp>::type;
1156#endif
1157
1158// add_pointer
1159
1160template <class _Tp,
1161        bool = __is_referenceable<_Tp>::value ||
1162                is_same<typename remove_cv<_Tp>::type, void>::value>
1163struct __add_pointer_impl
1164    {typedef typename remove_reference<_Tp>::type* type;};
1165template <class _Tp> struct __add_pointer_impl<_Tp, false>
1166    {typedef _Tp type;};
1167
1168template <class _Tp> struct _LIBCPP_TEMPLATE_VIS add_pointer
1169    {typedef typename __add_pointer_impl<_Tp>::type type;};
1170
1171#if _LIBCPP_STD_VER > 11
1172template <class _Tp> using add_pointer_t = typename add_pointer<_Tp>::type;
1173#endif
1174
1175// is_signed
1176
1177template <class _Tp, bool = is_integral<_Tp>::value>
1178struct __libcpp_is_signed_impl : public _LIBCPP_BOOL_CONSTANT(_Tp(-1) < _Tp(0)) {};
1179
1180template <class _Tp>
1181struct __libcpp_is_signed_impl<_Tp, false> : public true_type {};  // floating point
1182
1183template <class _Tp, bool = is_arithmetic<_Tp>::value>
1184struct __libcpp_is_signed : public __libcpp_is_signed_impl<_Tp> {};
1185
1186template <class _Tp> struct __libcpp_is_signed<_Tp, false> : public false_type {};
1187
1188template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_signed : public __libcpp_is_signed<_Tp> {};
1189
1190#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1191template <class _Tp> _LIBCPP_CONSTEXPR bool is_signed_v
1192    = is_signed<_Tp>::value;
1193#endif
1194
1195// is_unsigned
1196
1197template <class _Tp, bool = is_integral<_Tp>::value>
1198struct __libcpp_is_unsigned_impl : public _LIBCPP_BOOL_CONSTANT(_Tp(0) < _Tp(-1)) {};
1199
1200template <class _Tp>
1201struct __libcpp_is_unsigned_impl<_Tp, false> : public false_type {};  // floating point
1202
1203template <class _Tp, bool = is_arithmetic<_Tp>::value>
1204struct __libcpp_is_unsigned : public __libcpp_is_unsigned_impl<_Tp> {};
1205
1206template <class _Tp> struct __libcpp_is_unsigned<_Tp, false> : public false_type {};
1207
1208template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_unsigned : public __libcpp_is_unsigned<_Tp> {};
1209
1210#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1211template <class _Tp> _LIBCPP_CONSTEXPR bool is_unsigned_v
1212    = is_unsigned<_Tp>::value;
1213#endif
1214
1215// rank
1216
1217template <class _Tp> struct _LIBCPP_TEMPLATE_VIS rank
1218    : public integral_constant<size_t, 0> {};
1219template <class _Tp> struct _LIBCPP_TEMPLATE_VIS rank<_Tp[]>
1220    : public integral_constant<size_t, rank<_Tp>::value + 1> {};
1221template <class _Tp, size_t _Np> struct _LIBCPP_TEMPLATE_VIS rank<_Tp[_Np]>
1222    : public integral_constant<size_t, rank<_Tp>::value + 1> {};
1223
1224#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1225template <class _Tp> _LIBCPP_CONSTEXPR size_t rank_v
1226    = rank<_Tp>::value;
1227#endif
1228
1229// extent
1230
1231template <class _Tp, unsigned _Ip = 0> struct _LIBCPP_TEMPLATE_VIS extent
1232    : public integral_constant<size_t, 0> {};
1233template <class _Tp> struct _LIBCPP_TEMPLATE_VIS extent<_Tp[], 0>
1234    : public integral_constant<size_t, 0> {};
1235template <class _Tp, unsigned _Ip> struct _LIBCPP_TEMPLATE_VIS extent<_Tp[], _Ip>
1236    : public integral_constant<size_t, extent<_Tp, _Ip-1>::value> {};
1237template <class _Tp, size_t _Np> struct _LIBCPP_TEMPLATE_VIS extent<_Tp[_Np], 0>
1238    : public integral_constant<size_t, _Np> {};
1239template <class _Tp, size_t _Np, unsigned _Ip> struct _LIBCPP_TEMPLATE_VIS extent<_Tp[_Np], _Ip>
1240    : public integral_constant<size_t, extent<_Tp, _Ip-1>::value> {};
1241
1242#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1243template <class _Tp, unsigned _Ip = 0> _LIBCPP_CONSTEXPR size_t extent_v
1244    = extent<_Tp, _Ip>::value;
1245#endif
1246
1247// remove_extent
1248
1249template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_extent
1250    {typedef _Tp type;};
1251template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_extent<_Tp[]>
1252    {typedef _Tp type;};
1253template <class _Tp, size_t _Np> struct _LIBCPP_TEMPLATE_VIS remove_extent<_Tp[_Np]>
1254    {typedef _Tp type;};
1255
1256#if _LIBCPP_STD_VER > 11
1257template <class _Tp> using remove_extent_t = typename remove_extent<_Tp>::type;
1258#endif
1259
1260// remove_all_extents
1261
1262template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_all_extents
1263    {typedef _Tp type;};
1264template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_all_extents<_Tp[]>
1265    {typedef typename remove_all_extents<_Tp>::type type;};
1266template <class _Tp, size_t _Np> struct _LIBCPP_TEMPLATE_VIS remove_all_extents<_Tp[_Np]>
1267    {typedef typename remove_all_extents<_Tp>::type type;};
1268
1269#if _LIBCPP_STD_VER > 11
1270template <class _Tp> using remove_all_extents_t = typename remove_all_extents<_Tp>::type;
1271#endif
1272
1273// decay
1274
1275template <class _Tp>
1276struct _LIBCPP_TEMPLATE_VIS decay
1277{
1278private:
1279    typedef typename remove_reference<_Tp>::type _Up;
1280public:
1281    typedef typename conditional
1282                     <
1283                         is_array<_Up>::value,
1284                         typename remove_extent<_Up>::type*,
1285                         typename conditional
1286                         <
1287                              is_function<_Up>::value,
1288                              typename add_pointer<_Up>::type,
1289                              typename remove_cv<_Up>::type
1290                         >::type
1291                     >::type type;
1292};
1293
1294#if _LIBCPP_STD_VER > 11
1295template <class _Tp> using decay_t = typename decay<_Tp>::type;
1296#endif
1297
1298// is_abstract
1299
1300namespace __is_abstract_imp
1301{
1302template <class _Tp> char  __test(_Tp (*)[1]);
1303template <class _Tp> __two __test(...);
1304}
1305
1306template <class _Tp, bool = is_class<_Tp>::value>
1307struct __libcpp_abstract : public integral_constant<bool, sizeof(__is_abstract_imp::__test<_Tp>(0)) != 1> {};
1308
1309template <class _Tp> struct __libcpp_abstract<_Tp, false> : public false_type {};
1310
1311template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_abstract : public __libcpp_abstract<_Tp> {};
1312
1313#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1314template <class _Tp> _LIBCPP_CONSTEXPR bool is_abstract_v
1315    = is_abstract<_Tp>::value;
1316#endif
1317
1318// is_final
1319
1320#if defined(_LIBCPP_HAS_IS_FINAL)
1321template <class _Tp> struct _LIBCPP_TEMPLATE_VIS
1322__libcpp_is_final : public integral_constant<bool, __is_final(_Tp)> {};
1323#else
1324template <class _Tp> struct _LIBCPP_TEMPLATE_VIS
1325__libcpp_is_final : public false_type {};
1326#endif
1327
1328#if defined(_LIBCPP_HAS_IS_FINAL) && _LIBCPP_STD_VER > 11
1329template <class _Tp> struct _LIBCPP_TEMPLATE_VIS
1330is_final : public integral_constant<bool, __is_final(_Tp)> {};
1331#endif
1332
1333#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1334template <class _Tp> _LIBCPP_CONSTEXPR bool is_final_v
1335    = is_final<_Tp>::value;
1336#endif
1337
1338// is_base_of
1339
1340#ifdef _LIBCPP_HAS_IS_BASE_OF
1341
1342template <class _Bp, class _Dp>
1343struct _LIBCPP_TEMPLATE_VIS is_base_of
1344    : public integral_constant<bool, __is_base_of(_Bp, _Dp)> {};
1345
1346#else  // _LIBCPP_HAS_IS_BASE_OF
1347
1348namespace __is_base_of_imp
1349{
1350template <class _Tp>
1351struct _Dst
1352{
1353    _Dst(const volatile _Tp &);
1354};
1355template <class _Tp>
1356struct _Src
1357{
1358    operator const volatile _Tp &();
1359    template <class _Up> operator const _Dst<_Up> &();
1360};
1361template <size_t> struct __one { typedef char type; };
1362template <class _Bp, class _Dp> typename __one<sizeof(_Dst<_Bp>(declval<_Src<_Dp> >()))>::type __test(int);
1363template <class _Bp, class _Dp> __two __test(...);
1364}
1365
1366template <class _Bp, class _Dp>
1367struct _LIBCPP_TEMPLATE_VIS is_base_of
1368    : public integral_constant<bool, is_class<_Bp>::value &&
1369                                     sizeof(__is_base_of_imp::__test<_Bp, _Dp>(0)) == 2> {};
1370
1371#endif  // _LIBCPP_HAS_IS_BASE_OF
1372
1373#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1374template <class _Bp, class _Dp> _LIBCPP_CONSTEXPR bool is_base_of_v
1375    = is_base_of<_Bp, _Dp>::value;
1376#endif
1377
1378// is_convertible
1379
1380#if __has_feature(is_convertible_to) && !defined(_LIBCPP_USE_IS_CONVERTIBLE_FALLBACK)
1381
1382template <class _T1, class _T2> struct _LIBCPP_TEMPLATE_VIS is_convertible
1383    : public integral_constant<bool, __is_convertible_to(_T1, _T2) &&
1384                                     !is_abstract<_T2>::value> {};
1385
1386#else  // __has_feature(is_convertible_to)
1387
1388namespace __is_convertible_imp
1389{
1390template <class _Tp> void  __test_convert(_Tp);
1391
1392template <class _From, class _To, class = void>
1393struct __is_convertible_test : public false_type {};
1394
1395template <class _From, class _To>
1396struct __is_convertible_test<_From, _To,
1397    decltype(_VSTD::__is_convertible_imp::__test_convert<_To>(_VSTD::declval<_From>()))> : public true_type
1398{};
1399
1400template <class _Tp, bool _IsArray =    is_array<_Tp>::value,
1401                     bool _IsFunction = is_function<_Tp>::value,
1402                     bool _IsVoid =     is_void<_Tp>::value>
1403                     struct __is_array_function_or_void                          {enum {value = 0};};
1404template <class _Tp> struct __is_array_function_or_void<_Tp, true, false, false> {enum {value = 1};};
1405template <class _Tp> struct __is_array_function_or_void<_Tp, false, true, false> {enum {value = 2};};
1406template <class _Tp> struct __is_array_function_or_void<_Tp, false, false, true> {enum {value = 3};};
1407}
1408
1409template <class _Tp,
1410    unsigned = __is_convertible_imp::__is_array_function_or_void<typename remove_reference<_Tp>::type>::value>
1411struct __is_convertible_check
1412{
1413    static const size_t __v = 0;
1414};
1415
1416template <class _Tp>
1417struct __is_convertible_check<_Tp, 0>
1418{
1419    static const size_t __v = sizeof(_Tp);
1420};
1421
1422template <class _T1, class _T2,
1423    unsigned _T1_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T1>::value,
1424    unsigned _T2_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T2>::value>
1425struct __is_convertible
1426    : public integral_constant<bool,
1427        __is_convertible_imp::__is_convertible_test<_T1, _T2>::value
1428#if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1429         && !(!is_function<_T1>::value && !is_reference<_T1>::value && is_reference<_T2>::value
1430              && (!is_const<typename remove_reference<_T2>::type>::value
1431                  || is_volatile<typename remove_reference<_T2>::type>::value)
1432                  && (is_same<typename remove_cv<_T1>::type,
1433                              typename remove_cv<typename remove_reference<_T2>::type>::type>::value
1434                      || is_base_of<typename remove_reference<_T2>::type, _T1>::value))
1435#endif
1436    >
1437{};
1438
1439template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 1> : public false_type {};
1440template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 1> : public false_type {};
1441template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 1> : public false_type {};
1442template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 1> : public false_type {};
1443
1444template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 2> : public false_type {};
1445template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 2> : public false_type {};
1446template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 2> : public false_type {};
1447template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 2> : public false_type {};
1448
1449template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 3> : public false_type {};
1450template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 3> : public false_type {};
1451template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 3> : public false_type {};
1452template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 3> : public true_type {};
1453
1454template <class _T1, class _T2> struct _LIBCPP_TEMPLATE_VIS is_convertible
1455    : public __is_convertible<_T1, _T2>
1456{
1457    static const size_t __complete_check1 = __is_convertible_check<_T1>::__v;
1458    static const size_t __complete_check2 = __is_convertible_check<_T2>::__v;
1459};
1460
1461#endif  // __has_feature(is_convertible_to)
1462
1463#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1464template <class _From, class _To> _LIBCPP_CONSTEXPR bool is_convertible_v
1465    = is_convertible<_From, _To>::value;
1466#endif
1467
1468// is_empty
1469
1470#if __has_feature(is_empty) || (_GNUC_VER >= 407)
1471
1472template <class _Tp>
1473struct _LIBCPP_TEMPLATE_VIS is_empty
1474    : public integral_constant<bool, __is_empty(_Tp)> {};
1475
1476#else  // __has_feature(is_empty)
1477
1478template <class _Tp>
1479struct __is_empty1
1480    : public _Tp
1481{
1482    double __lx;
1483};
1484
1485struct __is_empty2
1486{
1487    double __lx;
1488};
1489
1490template <class _Tp, bool = is_class<_Tp>::value>
1491struct __libcpp_empty : public integral_constant<bool, sizeof(__is_empty1<_Tp>) == sizeof(__is_empty2)> {};
1492
1493template <class _Tp> struct __libcpp_empty<_Tp, false> : public false_type {};
1494
1495template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_empty : public __libcpp_empty<_Tp> {};
1496
1497#endif  // __has_feature(is_empty)
1498
1499#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1500template <class _Tp> _LIBCPP_CONSTEXPR bool is_empty_v
1501    = is_empty<_Tp>::value;
1502#endif
1503
1504// is_polymorphic
1505
1506#if __has_feature(is_polymorphic) || defined(_LIBCPP_COMPILER_MSVC)
1507
1508template <class _Tp>
1509struct _LIBCPP_TEMPLATE_VIS is_polymorphic
1510    : public integral_constant<bool, __is_polymorphic(_Tp)> {};
1511
1512#else
1513
1514template<typename _Tp> char &__is_polymorphic_impl(
1515    typename enable_if<sizeof((_Tp*)dynamic_cast<const volatile void*>(declval<_Tp*>())) != 0,
1516                       int>::type);
1517template<typename _Tp> __two &__is_polymorphic_impl(...);
1518
1519template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_polymorphic
1520    : public integral_constant<bool, sizeof(__is_polymorphic_impl<_Tp>(0)) == 1> {};
1521
1522#endif // __has_feature(is_polymorphic)
1523
1524#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1525template <class _Tp> _LIBCPP_CONSTEXPR bool is_polymorphic_v
1526    = is_polymorphic<_Tp>::value;
1527#endif
1528
1529// has_virtual_destructor
1530
1531#if __has_feature(has_virtual_destructor) || (_GNUC_VER >= 403)
1532
1533template <class _Tp> struct _LIBCPP_TEMPLATE_VIS has_virtual_destructor
1534    : public integral_constant<bool, __has_virtual_destructor(_Tp)> {};
1535
1536#else
1537
1538template <class _Tp> struct _LIBCPP_TEMPLATE_VIS has_virtual_destructor
1539    : public false_type {};
1540
1541#endif
1542
1543#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1544template <class _Tp> _LIBCPP_CONSTEXPR bool has_virtual_destructor_v
1545    = has_virtual_destructor<_Tp>::value;
1546#endif
1547
1548// alignment_of
1549
1550template <class _Tp> struct _LIBCPP_TEMPLATE_VIS alignment_of
1551    : public integral_constant<size_t, __alignof__(_Tp)> {};
1552
1553#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
1554template <class _Tp> _LIBCPP_CONSTEXPR size_t alignment_of_v
1555    = alignment_of<_Tp>::value;
1556#endif
1557
1558// aligned_storage
1559
1560template <class _Hp, class _Tp>
1561struct __type_list
1562{
1563    typedef _Hp _Head;
1564    typedef _Tp _Tail;
1565};
1566
1567struct __nat
1568{
1569#ifndef _LIBCPP_CXX03_LANG
1570    __nat() = delete;
1571    __nat(const __nat&) = delete;
1572    __nat& operator=(const __nat&) = delete;
1573    ~__nat() = delete;
1574#endif
1575};
1576
1577template <class _Tp>
1578struct __align_type
1579{
1580    static const size_t value = alignment_of<_Tp>::value;
1581    typedef _Tp type;
1582};
1583
1584struct __struct_double {long double __lx;};
1585struct __struct_double4 {double __lx[4];};
1586
1587typedef
1588    __type_list<__align_type<unsigned char>,
1589    __type_list<__align_type<unsigned short>,
1590    __type_list<__align_type<unsigned int>,
1591    __type_list<__align_type<unsigned long>,
1592    __type_list<__align_type<unsigned long long>,
1593    __type_list<__align_type<double>,
1594    __type_list<__align_type<long double>,
1595    __type_list<__align_type<__struct_double>,
1596    __type_list<__align_type<__struct_double4>,
1597    __type_list<__align_type<int*>,
1598    __nat
1599    > > > > > > > > > > __all_types;
1600
1601template <class _TL, size_t _Align> struct __find_pod;
1602
1603template <class _Hp, size_t _Align>
1604struct __find_pod<__type_list<_Hp, __nat>, _Align>
1605{
1606    typedef typename conditional<
1607                             _Align == _Hp::value,
1608                             typename _Hp::type,
1609                             void
1610                         >::type type;
1611};
1612
1613template <class _Hp, class _Tp, size_t _Align>
1614struct __find_pod<__type_list<_Hp, _Tp>, _Align>
1615{
1616    typedef typename conditional<
1617                             _Align == _Hp::value,
1618                             typename _Hp::type,
1619                             typename __find_pod<_Tp, _Align>::type
1620                         >::type type;
1621};
1622
1623template <class _TL, size_t _Len> struct __find_max_align;
1624
1625template <class _Hp, size_t _Len>
1626struct __find_max_align<__type_list<_Hp, __nat>, _Len> : public integral_constant<size_t, _Hp::value> {};
1627
1628template <size_t _Len, size_t _A1, size_t _A2>
1629struct __select_align
1630{
1631private:
1632    static const size_t __min = _A2 < _A1 ? _A2 : _A1;
1633    static const size_t __max = _A1 < _A2 ? _A2 : _A1;
1634public:
1635    static const size_t value = _Len < __max ? __min : __max;
1636};
1637
1638template <class _Hp, class _Tp, size_t _Len>
1639struct __find_max_align<__type_list<_Hp, _Tp>, _Len>
1640    : public integral_constant<size_t, __select_align<_Len, _Hp::value, __find_max_align<_Tp, _Len>::value>::value> {};
1641
1642template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
1643struct _LIBCPP_TEMPLATE_VIS aligned_storage
1644{
1645    typedef typename __find_pod<__all_types, _Align>::type _Aligner;
1646    static_assert(!is_void<_Aligner>::value, "");
1647    union type
1648    {
1649        _Aligner __align;
1650        unsigned char __data[(_Len + _Align - 1)/_Align * _Align];
1651    };
1652};
1653
1654#if _LIBCPP_STD_VER > 11
1655template <size_t _Len, size_t _Align = __find_max_align<__all_types, _Len>::value>
1656    using aligned_storage_t = typename aligned_storage<_Len, _Align>::type;
1657#endif
1658
1659#define _CREATE_ALIGNED_STORAGE_SPECIALIZATION(n) \
1660template <size_t _Len>\
1661struct _LIBCPP_TEMPLATE_VIS aligned_storage<_Len, n>\
1662{\
1663    struct _ALIGNAS(n) type\
1664    {\
1665        unsigned char __lx[(_Len + n - 1)/n * n];\
1666    };\
1667}
1668
1669_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1);
1670_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2);
1671_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4);
1672_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x8);
1673_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x10);
1674_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x20);
1675_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x40);
1676_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x80);
1677_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x100);
1678_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x200);
1679_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x400);
1680_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x800);
1681_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1000);
1682_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2000);
1683// PE/COFF does not support alignment beyond 8192 (=0x2000)
1684#if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
1685_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4000);
1686#endif // !defined(_LIBCPP_OBJECT_FORMAT_COFF)
1687
1688#undef _CREATE_ALIGNED_STORAGE_SPECIALIZATION
1689
1690#ifndef _LIBCPP_HAS_NO_VARIADICS
1691
1692// aligned_union
1693
1694template <size_t _I0, size_t ..._In>
1695struct __static_max;
1696
1697template <size_t _I0>
1698struct __static_max<_I0>
1699{
1700    static const size_t value = _I0;
1701};
1702
1703template <size_t _I0, size_t _I1, size_t ..._In>
1704struct __static_max<_I0, _I1, _In...>
1705{
1706    static const size_t value = _I0 >= _I1 ? __static_max<_I0, _In...>::value :
1707                                             __static_max<_I1, _In...>::value;
1708};
1709
1710template <size_t _Len, class _Type0, class ..._Types>
1711struct aligned_union
1712{
1713    static const size_t alignment_value = __static_max<__alignof__(_Type0),
1714                                                       __alignof__(_Types)...>::value;
1715    static const size_t __len = __static_max<_Len, sizeof(_Type0),
1716                                             sizeof(_Types)...>::value;
1717    typedef typename aligned_storage<__len, alignment_value>::type type;
1718};
1719
1720#if _LIBCPP_STD_VER > 11
1721template <size_t _Len, class ..._Types> using aligned_union_t = typename aligned_union<_Len, _Types...>::type;
1722#endif
1723
1724#endif  // _LIBCPP_HAS_NO_VARIADICS
1725
1726template <class _Tp>
1727struct __numeric_type
1728{
1729   static void __test(...);
1730   static float __test(float);
1731   static double __test(char);
1732   static double __test(int);
1733   static double __test(unsigned);
1734   static double __test(long);
1735   static double __test(unsigned long);
1736   static double __test(long long);
1737   static double __test(unsigned long long);
1738   static double __test(double);
1739   static long double __test(long double);
1740
1741   typedef decltype(__test(declval<_Tp>())) type;
1742   static const bool value = !is_same<type, void>::value;
1743};
1744
1745template <>
1746struct __numeric_type<void>
1747{
1748   static const bool value = true;
1749};
1750
1751// __promote
1752
1753template <class _A1, class _A2 = void, class _A3 = void,
1754          bool = __numeric_type<_A1>::value &&
1755                 __numeric_type<_A2>::value &&
1756                 __numeric_type<_A3>::value>
1757class __promote_imp
1758{
1759public:
1760    static const bool value = false;
1761};
1762
1763template <class _A1, class _A2, class _A3>
1764class __promote_imp<_A1, _A2, _A3, true>
1765{
1766private:
1767    typedef typename __promote_imp<_A1>::type __type1;
1768    typedef typename __promote_imp<_A2>::type __type2;
1769    typedef typename __promote_imp<_A3>::type __type3;
1770public:
1771    typedef decltype(__type1() + __type2() + __type3()) type;
1772    static const bool value = true;
1773};
1774
1775template <class _A1, class _A2>
1776class __promote_imp<_A1, _A2, void, true>
1777{
1778private:
1779    typedef typename __promote_imp<_A1>::type __type1;
1780    typedef typename __promote_imp<_A2>::type __type2;
1781public:
1782    typedef decltype(__type1() + __type2()) type;
1783    static const bool value = true;
1784};
1785
1786template <class _A1>
1787class __promote_imp<_A1, void, void, true>
1788{
1789public:
1790    typedef typename __numeric_type<_A1>::type type;
1791    static const bool value = true;
1792};
1793
1794template <class _A1, class _A2 = void, class _A3 = void>
1795class __promote : public __promote_imp<_A1, _A2, _A3> {};
1796
1797// make_signed / make_unsigned
1798
1799typedef
1800    __type_list<signed char,
1801    __type_list<signed short,
1802    __type_list<signed int,
1803    __type_list<signed long,
1804    __type_list<signed long long,
1805#ifndef _LIBCPP_HAS_NO_INT128
1806    __type_list<__int128_t,
1807#endif
1808    __nat
1809#ifndef _LIBCPP_HAS_NO_INT128
1810    >
1811#endif
1812    > > > > > __signed_types;
1813
1814typedef
1815    __type_list<unsigned char,
1816    __type_list<unsigned short,
1817    __type_list<unsigned int,
1818    __type_list<unsigned long,
1819    __type_list<unsigned long long,
1820#ifndef _LIBCPP_HAS_NO_INT128
1821    __type_list<__uint128_t,
1822#endif
1823    __nat
1824#ifndef _LIBCPP_HAS_NO_INT128
1825    >
1826#endif
1827    > > > > > __unsigned_types;
1828
1829template <class _TypeList, size_t _Size, bool = _Size <= sizeof(typename _TypeList::_Head)> struct __find_first;
1830
1831template <class _Hp, class _Tp, size_t _Size>
1832struct __find_first<__type_list<_Hp, _Tp>, _Size, true>
1833{
1834    typedef _Hp type;
1835};
1836
1837template <class _Hp, class _Tp, size_t _Size>
1838struct __find_first<__type_list<_Hp, _Tp>, _Size, false>
1839{
1840    typedef typename __find_first<_Tp, _Size>::type type;
1841};
1842
1843template <class _Tp, class _Up, bool = is_const<typename remove_reference<_Tp>::type>::value,
1844                             bool = is_volatile<typename remove_reference<_Tp>::type>::value>
1845struct __apply_cv
1846{
1847    typedef _Up type;
1848};
1849
1850template <class _Tp, class _Up>
1851struct __apply_cv<_Tp, _Up, true, false>
1852{
1853    typedef const _Up type;
1854};
1855
1856template <class _Tp, class _Up>
1857struct __apply_cv<_Tp, _Up, false, true>
1858{
1859    typedef volatile _Up type;
1860};
1861
1862template <class _Tp, class _Up>
1863struct __apply_cv<_Tp, _Up, true, true>
1864{
1865    typedef const volatile _Up type;
1866};
1867
1868template <class _Tp, class _Up>
1869struct __apply_cv<_Tp&, _Up, false, false>
1870{
1871    typedef _Up& type;
1872};
1873
1874template <class _Tp, class _Up>
1875struct __apply_cv<_Tp&, _Up, true, false>
1876{
1877    typedef const _Up& type;
1878};
1879
1880template <class _Tp, class _Up>
1881struct __apply_cv<_Tp&, _Up, false, true>
1882{
1883    typedef volatile _Up& type;
1884};
1885
1886template <class _Tp, class _Up>
1887struct __apply_cv<_Tp&, _Up, true, true>
1888{
1889    typedef const volatile _Up& type;
1890};
1891
1892template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
1893struct __make_signed {};
1894
1895template <class _Tp>
1896struct __make_signed<_Tp, true>
1897{
1898    typedef typename __find_first<__signed_types, sizeof(_Tp)>::type type;
1899};
1900
1901template <> struct __make_signed<bool,               true> {};
1902template <> struct __make_signed<  signed short,     true> {typedef short     type;};
1903template <> struct __make_signed<unsigned short,     true> {typedef short     type;};
1904template <> struct __make_signed<  signed int,       true> {typedef int       type;};
1905template <> struct __make_signed<unsigned int,       true> {typedef int       type;};
1906template <> struct __make_signed<  signed long,      true> {typedef long      type;};
1907template <> struct __make_signed<unsigned long,      true> {typedef long      type;};
1908template <> struct __make_signed<  signed long long, true> {typedef long long type;};
1909template <> struct __make_signed<unsigned long long, true> {typedef long long type;};
1910#ifndef _LIBCPP_HAS_NO_INT128
1911template <> struct __make_signed<__int128_t,         true> {typedef __int128_t type;};
1912template <> struct __make_signed<__uint128_t,        true> {typedef __int128_t type;};
1913#endif
1914
1915template <class _Tp>
1916struct _LIBCPP_TEMPLATE_VIS make_signed
1917{
1918    typedef typename __apply_cv<_Tp, typename __make_signed<typename remove_cv<_Tp>::type>::type>::type type;
1919};
1920
1921#if _LIBCPP_STD_VER > 11
1922template <class _Tp> using make_signed_t = typename make_signed<_Tp>::type;
1923#endif
1924
1925template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
1926struct __make_unsigned {};
1927
1928template <class _Tp>
1929struct __make_unsigned<_Tp, true>
1930{
1931    typedef typename __find_first<__unsigned_types, sizeof(_Tp)>::type type;
1932};
1933
1934template <> struct __make_unsigned<bool,               true> {};
1935template <> struct __make_unsigned<  signed short,     true> {typedef unsigned short     type;};
1936template <> struct __make_unsigned<unsigned short,     true> {typedef unsigned short     type;};
1937template <> struct __make_unsigned<  signed int,       true> {typedef unsigned int       type;};
1938template <> struct __make_unsigned<unsigned int,       true> {typedef unsigned int       type;};
1939template <> struct __make_unsigned<  signed long,      true> {typedef unsigned long      type;};
1940template <> struct __make_unsigned<unsigned long,      true> {typedef unsigned long      type;};
1941template <> struct __make_unsigned<  signed long long, true> {typedef unsigned long long type;};
1942template <> struct __make_unsigned<unsigned long long, true> {typedef unsigned long long type;};
1943#ifndef _LIBCPP_HAS_NO_INT128
1944template <> struct __make_unsigned<__int128_t,         true> {typedef __uint128_t        type;};
1945template <> struct __make_unsigned<__uint128_t,        true> {typedef __uint128_t        type;};
1946#endif
1947
1948template <class _Tp>
1949struct _LIBCPP_TEMPLATE_VIS make_unsigned
1950{
1951    typedef typename __apply_cv<_Tp, typename __make_unsigned<typename remove_cv<_Tp>::type>::type>::type type;
1952};
1953
1954#if _LIBCPP_STD_VER > 11
1955template <class _Tp> using make_unsigned_t = typename make_unsigned<_Tp>::type;
1956#endif
1957
1958#ifdef _LIBCPP_HAS_NO_VARIADICS
1959
1960template <class _Tp, class _Up = void, class _Vp = void>
1961struct _LIBCPP_TEMPLATE_VIS common_type
1962{
1963public:
1964    typedef typename common_type<typename common_type<_Tp, _Up>::type, _Vp>::type type;
1965};
1966
1967template <class _Tp>
1968struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, void, void>
1969{
1970public:
1971    typedef typename decay<_Tp>::type type;
1972};
1973
1974template <class _Tp, class _Up>
1975struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, _Up, void>
1976{
1977    typedef typename decay<decltype(
1978        true ? _VSTD::declval<_Tp>() : _VSTD::declval<_Up>()
1979      )>::type type;
1980};
1981
1982#else  // _LIBCPP_HAS_NO_VARIADICS
1983
1984// bullet 1 - sizeof...(Tp) == 0
1985
1986template <class ..._Tp>
1987struct _LIBCPP_TEMPLATE_VIS common_type {};
1988
1989// bullet 2 - sizeof...(Tp) == 1
1990
1991template <class _Tp>
1992struct _LIBCPP_TEMPLATE_VIS common_type<_Tp>
1993{
1994    typedef typename decay<_Tp>::type type;
1995};
1996
1997// bullet 3 - sizeof...(Tp) == 2
1998
1999template <class _Tp, class _Up, class = void>
2000struct __common_type2_imp {};
2001
2002template <class _Tp, class _Up>
2003struct __common_type2_imp<_Tp, _Up,
2004    typename __void_t<decltype(
2005        true ? _VSTD::declval<_Tp>() : _VSTD::declval<_Up>()
2006    )>::type>
2007{
2008    typedef typename decay<decltype(
2009        true ? _VSTD::declval<_Tp>() : _VSTD::declval<_Up>()
2010    )>::type type;
2011};
2012
2013template <class _Tp, class _Up,
2014          class _DTp = typename decay<_Tp>::type,
2015          class _DUp = typename decay<_Up>::type>
2016using __common_type2 =
2017  typename conditional<
2018    is_same<_Tp, _DTp>::value && is_same<_Up, _DUp>::value,
2019    __common_type2_imp<_Tp, _Up>,
2020    common_type<_DTp, _DUp>
2021  >::type;
2022
2023template <class _Tp, class _Up>
2024struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, _Up>
2025    : __common_type2<_Tp, _Up> {};
2026
2027// bullet 4 - sizeof...(Tp) > 2
2028
2029template <class ...Tp> struct __common_types;
2030
2031template <class, class = void>
2032struct __common_type_impl {};
2033
2034template <class _Tp, class _Up>
2035struct __common_type_impl<
2036    __common_types<_Tp, _Up>,
2037    typename __void_t<typename common_type<_Tp, _Up>::type>::type>
2038{
2039  typedef typename common_type<_Tp, _Up>::type type;
2040};
2041
2042template <class _Tp, class _Up, class ..._Vp>
2043struct __common_type_impl<__common_types<_Tp, _Up, _Vp...>,
2044    typename __void_t<typename common_type<_Tp, _Up>::type>::type>
2045  : __common_type_impl<
2046      __common_types<typename common_type<_Tp, _Up>::type, _Vp...> >
2047{
2048
2049};
2050
2051template <class _Tp, class _Up, class ..._Vp>
2052struct _LIBCPP_TEMPLATE_VIS common_type<_Tp, _Up, _Vp...>
2053    : __common_type_impl<__common_types<_Tp, _Up, _Vp...> > {};
2054
2055#if _LIBCPP_STD_VER > 11
2056template <class ..._Tp> using common_type_t = typename common_type<_Tp...>::type;
2057#endif
2058
2059#endif  // _LIBCPP_HAS_NO_VARIADICS
2060
2061// is_assignable
2062
2063template<typename, typename _Tp> struct __select_2nd { typedef _Tp type; };
2064
2065template <class _Tp, class _Arg>
2066typename __select_2nd<decltype((_VSTD::declval<_Tp>() = _VSTD::declval<_Arg>())), true_type>::type
2067__is_assignable_test(int);
2068
2069template <class, class>
2070false_type __is_assignable_test(...);
2071
2072
2073template <class _Tp, class _Arg, bool = is_void<_Tp>::value || is_void<_Arg>::value>
2074struct __is_assignable_imp
2075    : public decltype((_VSTD::__is_assignable_test<_Tp, _Arg>(0))) {};
2076
2077template <class _Tp, class _Arg>
2078struct __is_assignable_imp<_Tp, _Arg, true>
2079    : public false_type
2080{
2081};
2082
2083template <class _Tp, class _Arg>
2084struct is_assignable
2085    : public __is_assignable_imp<_Tp, _Arg> {};
2086
2087#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
2088template <class _Tp, class _Arg> _LIBCPP_CONSTEXPR bool is_assignable_v
2089    = is_assignable<_Tp, _Arg>::value;
2090#endif
2091
2092// is_copy_assignable
2093
2094template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_copy_assignable
2095    : public is_assignable<typename add_lvalue_reference<_Tp>::type,
2096                  typename add_lvalue_reference<typename add_const<_Tp>::type>::type> {};
2097
2098#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
2099template <class _Tp> _LIBCPP_CONSTEXPR bool is_copy_assignable_v
2100    = is_copy_assignable<_Tp>::value;
2101#endif
2102
2103// is_move_assignable
2104
2105template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_move_assignable
2106#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2107    : public is_assignable<typename add_lvalue_reference<_Tp>::type,
2108                           typename add_rvalue_reference<_Tp>::type> {};
2109#else
2110    : public is_copy_assignable<_Tp> {};
2111#endif
2112
2113#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
2114template <class _Tp> _LIBCPP_CONSTEXPR bool is_move_assignable_v
2115    = is_move_assignable<_Tp>::value;
2116#endif
2117
2118// is_destructible
2119
2120//  if it's a reference, return true
2121//  if it's a function, return false
2122//  if it's   void,     return false
2123//  if it's an array of unknown bound, return false
2124//  Otherwise, return "std::declval<_Up&>().~_Up()" is well-formed
2125//    where _Up is remove_all_extents<_Tp>::type
2126
2127template <class>
2128struct __is_destructible_apply { typedef int type; };
2129
2130template <typename _Tp>
2131struct __is_destructor_wellformed {
2132    template <typename _Tp1>
2133    static char  __test (
2134        typename __is_destructible_apply<decltype(_VSTD::declval<_Tp1&>().~_Tp1())>::type
2135    );
2136
2137    template <typename _Tp1>
2138    static __two __test (...);
2139
2140    static const bool value = sizeof(__test<_Tp>(12)) == sizeof(char);
2141};
2142
2143template <class _Tp, bool>
2144struct __destructible_imp;
2145
2146template <class _Tp>
2147struct __destructible_imp<_Tp, false>
2148   : public _VSTD::integral_constant<bool,
2149        __is_destructor_wellformed<typename _VSTD::remove_all_extents<_Tp>::type>::value> {};
2150
2151template <class _Tp>
2152struct __destructible_imp<_Tp, true>
2153    : public _VSTD::true_type {};
2154
2155template <class _Tp, bool>
2156struct __destructible_false;
2157
2158template <class _Tp>
2159struct __destructible_false<_Tp, false> : public __destructible_imp<_Tp, _VSTD::is_reference<_Tp>::value> {};
2160
2161template <class _Tp>
2162struct __destructible_false<_Tp, true> : public _VSTD::false_type {};
2163
2164template <class _Tp>
2165struct is_destructible
2166    : public __destructible_false<_Tp, _VSTD::is_function<_Tp>::value> {};
2167
2168template <class _Tp>
2169struct is_destructible<_Tp[]>
2170    : public _VSTD::false_type {};
2171
2172template <>
2173struct is_destructible<void>
2174    : public _VSTD::false_type {};
2175
2176#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
2177template <class _Tp> _LIBCPP_CONSTEXPR bool is_destructible_v
2178    = is_destructible<_Tp>::value;
2179#endif
2180
2181// move
2182
2183#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2184
2185template <class _Tp>
2186inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2187typename remove_reference<_Tp>::type&&
2188move(_Tp&& __t) _NOEXCEPT
2189{
2190    typedef typename remove_reference<_Tp>::type _Up;
2191    return static_cast<_Up&&>(__t);
2192}
2193
2194template <class _Tp>
2195inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2196_Tp&&
2197forward(typename remove_reference<_Tp>::type& __t) _NOEXCEPT
2198{
2199    return static_cast<_Tp&&>(__t);
2200}
2201
2202template <class _Tp>
2203inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2204_Tp&&
2205forward(typename remove_reference<_Tp>::type&& __t) _NOEXCEPT
2206{
2207    static_assert(!is_lvalue_reference<_Tp>::value,
2208                  "can not forward an rvalue as an lvalue");
2209    return static_cast<_Tp&&>(__t);
2210}
2211
2212#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2213
2214template <class _Tp>
2215inline _LIBCPP_INLINE_VISIBILITY
2216_Tp&
2217move(_Tp& __t)
2218{
2219    return __t;
2220}
2221
2222template <class _Tp>
2223inline _LIBCPP_INLINE_VISIBILITY
2224const _Tp&
2225move(const _Tp& __t)
2226{
2227    return __t;
2228}
2229
2230template <class _Tp>
2231inline _LIBCPP_INLINE_VISIBILITY
2232_Tp&
2233forward(typename remove_reference<_Tp>::type& __t) _NOEXCEPT
2234{
2235    return __t;
2236}
2237
2238
2239template <class _Tp>
2240class __rv
2241{
2242    typedef typename remove_reference<_Tp>::type _Trr;
2243    _Trr& t_;
2244public:
2245    _LIBCPP_INLINE_VISIBILITY
2246    _Trr* operator->() {return &t_;}
2247    _LIBCPP_INLINE_VISIBILITY
2248    explicit __rv(_Trr& __t) : t_(__t) {}
2249};
2250
2251#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2252
2253#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2254
2255template <class _Tp>
2256inline _LIBCPP_INLINE_VISIBILITY
2257typename decay<_Tp>::type
2258__decay_copy(_Tp&& __t)
2259{
2260    return _VSTD::forward<_Tp>(__t);
2261}
2262
2263#else
2264
2265template <class _Tp>
2266inline _LIBCPP_INLINE_VISIBILITY
2267typename decay<_Tp>::type
2268__decay_copy(const _Tp& __t)
2269{
2270    return _VSTD::forward<_Tp>(__t);
2271}
2272
2273#endif
2274
2275#ifndef _LIBCPP_HAS_NO_VARIADICS
2276
2277template <class _Rp, class _Class, class ..._Param>
2278struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...), true, false>
2279{
2280    typedef _Class _ClassType;
2281    typedef _Rp _ReturnType;
2282    typedef _Rp (_FnType) (_Param...);
2283};
2284
2285template <class _Rp, class _Class, class ..._Param>
2286struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...), true, false>
2287{
2288    typedef _Class _ClassType;
2289    typedef _Rp _ReturnType;
2290    typedef _Rp (_FnType) (_Param..., ...);
2291};
2292
2293template <class _Rp, class _Class, class ..._Param>
2294struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const, true, false>
2295{
2296    typedef _Class const _ClassType;
2297    typedef _Rp _ReturnType;
2298    typedef _Rp (_FnType) (_Param...);
2299};
2300
2301template <class _Rp, class _Class, class ..._Param>
2302struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const, true, false>
2303{
2304    typedef _Class const _ClassType;
2305    typedef _Rp _ReturnType;
2306    typedef _Rp (_FnType) (_Param..., ...);
2307};
2308
2309template <class _Rp, class _Class, class ..._Param>
2310struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile, true, false>
2311{
2312    typedef _Class volatile _ClassType;
2313    typedef _Rp _ReturnType;
2314    typedef _Rp (_FnType) (_Param...);
2315};
2316
2317template <class _Rp, class _Class, class ..._Param>
2318struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) volatile, true, false>
2319{
2320    typedef _Class volatile _ClassType;
2321    typedef _Rp _ReturnType;
2322    typedef _Rp (_FnType) (_Param..., ...);
2323};
2324
2325template <class _Rp, class _Class, class ..._Param>
2326struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile, true, false>
2327{
2328    typedef _Class const volatile _ClassType;
2329    typedef _Rp _ReturnType;
2330    typedef _Rp (_FnType) (_Param...);
2331};
2332
2333template <class _Rp, class _Class, class ..._Param>
2334struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const volatile, true, false>
2335{
2336    typedef _Class const volatile _ClassType;
2337    typedef _Rp _ReturnType;
2338    typedef _Rp (_FnType) (_Param..., ...);
2339};
2340
2341#if __has_feature(cxx_reference_qualified_functions) || \
2342    (defined(_GNUC_VER) && _GNUC_VER >= 409)
2343
2344template <class _Rp, class _Class, class ..._Param>
2345struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) &, true, false>
2346{
2347    typedef _Class& _ClassType;
2348    typedef _Rp _ReturnType;
2349    typedef _Rp (_FnType) (_Param...);
2350};
2351
2352template <class _Rp, class _Class, class ..._Param>
2353struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) &, true, false>
2354{
2355    typedef _Class& _ClassType;
2356    typedef _Rp _ReturnType;
2357    typedef _Rp (_FnType) (_Param..., ...);
2358};
2359
2360template <class _Rp, class _Class, class ..._Param>
2361struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const&, true, false>
2362{
2363    typedef _Class const& _ClassType;
2364    typedef _Rp _ReturnType;
2365    typedef _Rp (_FnType) (_Param...);
2366};
2367
2368template <class _Rp, class _Class, class ..._Param>
2369struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const&, true, false>
2370{
2371    typedef _Class const& _ClassType;
2372    typedef _Rp _ReturnType;
2373    typedef _Rp (_FnType) (_Param..., ...);
2374};
2375
2376template <class _Rp, class _Class, class ..._Param>
2377struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile&, true, false>
2378{
2379    typedef _Class volatile& _ClassType;
2380    typedef _Rp _ReturnType;
2381    typedef _Rp (_FnType) (_Param...);
2382};
2383
2384template <class _Rp, class _Class, class ..._Param>
2385struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) volatile&, true, false>
2386{
2387    typedef _Class volatile& _ClassType;
2388    typedef _Rp _ReturnType;
2389    typedef _Rp (_FnType) (_Param..., ...);
2390};
2391
2392template <class _Rp, class _Class, class ..._Param>
2393struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile&, true, false>
2394{
2395    typedef _Class const volatile& _ClassType;
2396    typedef _Rp _ReturnType;
2397    typedef _Rp (_FnType) (_Param...);
2398};
2399
2400template <class _Rp, class _Class, class ..._Param>
2401struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const volatile&, true, false>
2402{
2403    typedef _Class const volatile& _ClassType;
2404    typedef _Rp _ReturnType;
2405    typedef _Rp (_FnType) (_Param..., ...);
2406};
2407
2408template <class _Rp, class _Class, class ..._Param>
2409struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) &&, true, false>
2410{
2411    typedef _Class&& _ClassType;
2412    typedef _Rp _ReturnType;
2413    typedef _Rp (_FnType) (_Param...);
2414};
2415
2416template <class _Rp, class _Class, class ..._Param>
2417struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) &&, true, false>
2418{
2419    typedef _Class&& _ClassType;
2420    typedef _Rp _ReturnType;
2421    typedef _Rp (_FnType) (_Param..., ...);
2422};
2423
2424template <class _Rp, class _Class, class ..._Param>
2425struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const&&, true, false>
2426{
2427    typedef _Class const&& _ClassType;
2428    typedef _Rp _ReturnType;
2429    typedef _Rp (_FnType) (_Param...);
2430};
2431
2432template <class _Rp, class _Class, class ..._Param>
2433struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const&&, true, false>
2434{
2435    typedef _Class const&& _ClassType;
2436    typedef _Rp _ReturnType;
2437    typedef _Rp (_FnType) (_Param..., ...);
2438};
2439
2440template <class _Rp, class _Class, class ..._Param>
2441struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile&&, true, false>
2442{
2443    typedef _Class volatile&& _ClassType;
2444    typedef _Rp _ReturnType;
2445    typedef _Rp (_FnType) (_Param...);
2446};
2447
2448template <class _Rp, class _Class, class ..._Param>
2449struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) volatile&&, true, false>
2450{
2451    typedef _Class volatile&& _ClassType;
2452    typedef _Rp _ReturnType;
2453    typedef _Rp (_FnType) (_Param..., ...);
2454};
2455
2456template <class _Rp, class _Class, class ..._Param>
2457struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile&&, true, false>
2458{
2459    typedef _Class const volatile&& _ClassType;
2460    typedef _Rp _ReturnType;
2461    typedef _Rp (_FnType) (_Param...);
2462};
2463
2464template <class _Rp, class _Class, class ..._Param>
2465struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const volatile&&, true, false>
2466{
2467    typedef _Class const volatile&& _ClassType;
2468    typedef _Rp _ReturnType;
2469    typedef _Rp (_FnType) (_Param..., ...);
2470};
2471
2472#endif  // __has_feature(cxx_reference_qualified_functions) || _GNUC_VER >= 409
2473
2474#else  // _LIBCPP_HAS_NO_VARIADICS
2475
2476template <class _Rp, class _Class>
2477struct __member_pointer_traits_imp<_Rp (_Class::*)(), true, false>
2478{
2479    typedef _Class _ClassType;
2480    typedef _Rp _ReturnType;
2481    typedef _Rp (_FnType) ();
2482};
2483
2484template <class _Rp, class _Class>
2485struct __member_pointer_traits_imp<_Rp (_Class::*)(...), true, false>
2486{
2487    typedef _Class _ClassType;
2488    typedef _Rp _ReturnType;
2489    typedef _Rp (_FnType) (...);
2490};
2491
2492template <class _Rp, class _Class, class _P0>
2493struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0), true, false>
2494{
2495    typedef _Class _ClassType;
2496    typedef _Rp _ReturnType;
2497    typedef _Rp (_FnType) (_P0);
2498};
2499
2500template <class _Rp, class _Class, class _P0>
2501struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, ...), true, false>
2502{
2503    typedef _Class _ClassType;
2504    typedef _Rp _ReturnType;
2505    typedef _Rp (_FnType) (_P0, ...);
2506};
2507
2508template <class _Rp, class _Class, class _P0, class _P1>
2509struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1), true, false>
2510{
2511    typedef _Class _ClassType;
2512    typedef _Rp _ReturnType;
2513    typedef _Rp (_FnType) (_P0, _P1);
2514};
2515
2516template <class _Rp, class _Class, class _P0, class _P1>
2517struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, ...), true, false>
2518{
2519    typedef _Class _ClassType;
2520    typedef _Rp _ReturnType;
2521    typedef _Rp (_FnType) (_P0, _P1, ...);
2522};
2523
2524template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2525struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2), true, false>
2526{
2527    typedef _Class _ClassType;
2528    typedef _Rp _ReturnType;
2529    typedef _Rp (_FnType) (_P0, _P1, _P2);
2530};
2531
2532template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2533struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2, ...), true, false>
2534{
2535    typedef _Class _ClassType;
2536    typedef _Rp _ReturnType;
2537    typedef _Rp (_FnType) (_P0, _P1, _P2, ...);
2538};
2539
2540template <class _Rp, class _Class>
2541struct __member_pointer_traits_imp<_Rp (_Class::*)() const, true, false>
2542{
2543    typedef _Class const _ClassType;
2544    typedef _Rp _ReturnType;
2545    typedef _Rp (_FnType) ();
2546};
2547
2548template <class _Rp, class _Class>
2549struct __member_pointer_traits_imp<_Rp (_Class::*)(...) const, true, false>
2550{
2551    typedef _Class const _ClassType;
2552    typedef _Rp _ReturnType;
2553    typedef _Rp (_FnType) (...);
2554};
2555
2556template <class _Rp, class _Class, class _P0>
2557struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) const, true, false>
2558{
2559    typedef _Class const _ClassType;
2560    typedef _Rp _ReturnType;
2561    typedef _Rp (_FnType) (_P0);
2562};
2563
2564template <class _Rp, class _Class, class _P0>
2565struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, ...) const, true, false>
2566{
2567    typedef _Class const _ClassType;
2568    typedef _Rp _ReturnType;
2569    typedef _Rp (_FnType) (_P0, ...);
2570};
2571
2572template <class _Rp, class _Class, class _P0, class _P1>
2573struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) const, true, false>
2574{
2575    typedef _Class const _ClassType;
2576    typedef _Rp _ReturnType;
2577    typedef _Rp (_FnType) (_P0, _P1);
2578};
2579
2580template <class _Rp, class _Class, class _P0, class _P1>
2581struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, ...) const, true, false>
2582{
2583    typedef _Class const _ClassType;
2584    typedef _Rp _ReturnType;
2585    typedef _Rp (_FnType) (_P0, _P1, ...);
2586};
2587
2588template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2589struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) const, true, false>
2590{
2591    typedef _Class const _ClassType;
2592    typedef _Rp _ReturnType;
2593    typedef _Rp (_FnType) (_P0, _P1, _P2);
2594};
2595
2596template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2597struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2, ...) const, true, false>
2598{
2599    typedef _Class const _ClassType;
2600    typedef _Rp _ReturnType;
2601    typedef _Rp (_FnType) (_P0, _P1, _P2, ...);
2602};
2603
2604template <class _Rp, class _Class>
2605struct __member_pointer_traits_imp<_Rp (_Class::*)() volatile, true, false>
2606{
2607    typedef _Class volatile _ClassType;
2608    typedef _Rp _ReturnType;
2609    typedef _Rp (_FnType) ();
2610};
2611
2612template <class _Rp, class _Class>
2613struct __member_pointer_traits_imp<_Rp (_Class::*)(...) volatile, true, false>
2614{
2615    typedef _Class volatile _ClassType;
2616    typedef _Rp _ReturnType;
2617    typedef _Rp (_FnType) (...);
2618};
2619
2620template <class _Rp, class _Class, class _P0>
2621struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) volatile, true, false>
2622{
2623    typedef _Class volatile _ClassType;
2624    typedef _Rp _ReturnType;
2625    typedef _Rp (_FnType) (_P0);
2626};
2627
2628template <class _Rp, class _Class, class _P0>
2629struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, ...) volatile, true, false>
2630{
2631    typedef _Class volatile _ClassType;
2632    typedef _Rp _ReturnType;
2633    typedef _Rp (_FnType) (_P0, ...);
2634};
2635
2636template <class _Rp, class _Class, class _P0, class _P1>
2637struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) volatile, true, false>
2638{
2639    typedef _Class volatile _ClassType;
2640    typedef _Rp _ReturnType;
2641    typedef _Rp (_FnType) (_P0, _P1);
2642};
2643
2644template <class _Rp, class _Class, class _P0, class _P1>
2645struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, ...) volatile, true, false>
2646{
2647    typedef _Class volatile _ClassType;
2648    typedef _Rp _ReturnType;
2649    typedef _Rp (_FnType) (_P0, _P1, ...);
2650};
2651
2652template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2653struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) volatile, true, false>
2654{
2655    typedef _Class volatile _ClassType;
2656    typedef _Rp _ReturnType;
2657    typedef _Rp (_FnType) (_P0, _P1, _P2);
2658};
2659
2660template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2661struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2, ...) volatile, true, false>
2662{
2663    typedef _Class volatile _ClassType;
2664    typedef _Rp _ReturnType;
2665    typedef _Rp (_FnType) (_P0, _P1, _P2, ...);
2666};
2667
2668template <class _Rp, class _Class>
2669struct __member_pointer_traits_imp<_Rp (_Class::*)() const volatile, true, false>
2670{
2671    typedef _Class const volatile _ClassType;
2672    typedef _Rp _ReturnType;
2673    typedef _Rp (_FnType) ();
2674};
2675
2676template <class _Rp, class _Class>
2677struct __member_pointer_traits_imp<_Rp (_Class::*)(...) const volatile, true, false>
2678{
2679    typedef _Class const volatile _ClassType;
2680    typedef _Rp _ReturnType;
2681    typedef _Rp (_FnType) (...);
2682};
2683
2684template <class _Rp, class _Class, class _P0>
2685struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) const volatile, true, false>
2686{
2687    typedef _Class const volatile _ClassType;
2688    typedef _Rp _ReturnType;
2689    typedef _Rp (_FnType) (_P0);
2690};
2691
2692template <class _Rp, class _Class, class _P0>
2693struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, ...) const volatile, true, false>
2694{
2695    typedef _Class const volatile _ClassType;
2696    typedef _Rp _ReturnType;
2697    typedef _Rp (_FnType) (_P0, ...);
2698};
2699
2700template <class _Rp, class _Class, class _P0, class _P1>
2701struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) const volatile, true, false>
2702{
2703    typedef _Class const volatile _ClassType;
2704    typedef _Rp _ReturnType;
2705    typedef _Rp (_FnType) (_P0, _P1);
2706};
2707
2708template <class _Rp, class _Class, class _P0, class _P1>
2709struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, ...) const volatile, true, false>
2710{
2711    typedef _Class const volatile _ClassType;
2712    typedef _Rp _ReturnType;
2713    typedef _Rp (_FnType) (_P0, _P1, ...);
2714};
2715
2716template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2717struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) const volatile, true, false>
2718{
2719    typedef _Class const volatile _ClassType;
2720    typedef _Rp _ReturnType;
2721    typedef _Rp (_FnType) (_P0, _P1, _P2);
2722};
2723
2724template <class _Rp, class _Class, class _P0, class _P1, class _P2>
2725struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2, ...) const volatile, true, false>
2726{
2727    typedef _Class const volatile _ClassType;
2728    typedef _Rp _ReturnType;
2729    typedef _Rp (_FnType) (_P0, _P1, _P2, ...);
2730};
2731
2732#endif  // _LIBCPP_HAS_NO_VARIADICS
2733
2734template <class _Rp, class _Class>
2735struct __member_pointer_traits_imp<_Rp _Class::*, false, true>
2736{
2737    typedef _Class _ClassType;
2738    typedef _Rp _ReturnType;
2739};
2740
2741template <class _MP>
2742struct __member_pointer_traits
2743    : public __member_pointer_traits_imp<typename remove_cv<_MP>::type,
2744                    is_member_function_pointer<_MP>::value,
2745                    is_member_object_pointer<_MP>::value>
2746{
2747//     typedef ... _ClassType;
2748//     typedef ... _ReturnType;
2749//     typedef ... _FnType;
2750};
2751
2752
2753template <class _DecayedFp>
2754struct __member_pointer_class_type {};
2755
2756template <class _Ret, class _ClassType>
2757struct __member_pointer_class_type<_Ret _ClassType::*> {
2758  typedef _ClassType type;
2759};
2760
2761// result_of
2762
2763template <class _Callable> class result_of;
2764
2765#ifdef _LIBCPP_HAS_NO_VARIADICS
2766
2767template <class _Fn, bool, bool>
2768class __result_of
2769{
2770};
2771
2772template <class _Fn>
2773class __result_of<_Fn(), true, false>
2774{
2775public:
2776    typedef decltype(declval<_Fn>()()) type;
2777};
2778
2779template <class _Fn, class _A0>
2780class __result_of<_Fn(_A0), true, false>
2781{
2782public:
2783    typedef decltype(declval<_Fn>()(declval<_A0>())) type;
2784};
2785
2786template <class _Fn, class _A0, class _A1>
2787class __result_of<_Fn(_A0, _A1), true, false>
2788{
2789public:
2790    typedef decltype(declval<_Fn>()(declval<_A0>(), declval<_A1>())) type;
2791};
2792
2793template <class _Fn, class _A0, class _A1, class _A2>
2794class __result_of<_Fn(_A0, _A1, _A2), true, false>
2795{
2796public:
2797    typedef decltype(declval<_Fn>()(declval<_A0>(), declval<_A1>(), declval<_A2>())) type;
2798};
2799
2800template <class _MP, class _Tp, bool _IsMemberFunctionPtr>
2801struct __result_of_mp;
2802
2803// member function pointer
2804
2805template <class _MP, class _Tp>
2806struct __result_of_mp<_MP, _Tp, true>
2807    : public __identity<typename __member_pointer_traits<_MP>::_ReturnType>
2808{
2809};
2810
2811// member data pointer
2812
2813template <class _MP, class _Tp, bool>
2814struct __result_of_mdp;
2815
2816template <class _Rp, class _Class, class _Tp>
2817struct __result_of_mdp<_Rp _Class::*, _Tp, false>
2818{
2819    typedef typename __apply_cv<decltype(*_VSTD::declval<_Tp>()), _Rp>::type& type;
2820};
2821
2822template <class _Rp, class _Class, class _Tp>
2823struct __result_of_mdp<_Rp _Class::*, _Tp, true>
2824{
2825    typedef typename __apply_cv<_Tp, _Rp>::type& type;
2826};
2827
2828template <class _Rp, class _Class, class _Tp>
2829struct __result_of_mp<_Rp _Class::*, _Tp, false>
2830    : public __result_of_mdp<_Rp _Class::*, _Tp,
2831            is_base_of<_Class, typename remove_reference<_Tp>::type>::value>
2832{
2833};
2834
2835
2836
2837template <class _Fn, class _Tp>
2838class __result_of<_Fn(_Tp), false, true>  // _Fn must be member pointer
2839    : public __result_of_mp<typename remove_reference<_Fn>::type,
2840                            _Tp,
2841                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
2842{
2843};
2844
2845template <class _Fn, class _Tp, class _A0>
2846class __result_of<_Fn(_Tp, _A0), false, true>  // _Fn must be member pointer
2847    : public __result_of_mp<typename remove_reference<_Fn>::type,
2848                            _Tp,
2849                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
2850{
2851};
2852
2853template <class _Fn, class _Tp, class _A0, class _A1>
2854class __result_of<_Fn(_Tp, _A0, _A1), false, true>  // _Fn must be member pointer
2855    : public __result_of_mp<typename remove_reference<_Fn>::type,
2856                            _Tp,
2857                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
2858{
2859};
2860
2861template <class _Fn, class _Tp, class _A0, class _A1, class _A2>
2862class __result_of<_Fn(_Tp, _A0, _A1, _A2), false, true>  // _Fn must be member pointer
2863    : public __result_of_mp<typename remove_reference<_Fn>::type,
2864                            _Tp,
2865                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
2866{
2867};
2868
2869// result_of
2870
2871template <class _Fn>
2872class _LIBCPP_TEMPLATE_VIS result_of<_Fn()>
2873    : public __result_of<_Fn(),
2874                         is_class<typename remove_reference<_Fn>::type>::value ||
2875                         is_function<typename remove_pointer<typename remove_reference<_Fn>::type>::type>::value,
2876                         is_member_pointer<typename remove_reference<_Fn>::type>::value
2877                        >
2878{
2879};
2880
2881template <class _Fn, class _A0>
2882class _LIBCPP_TEMPLATE_VIS result_of<_Fn(_A0)>
2883    : public __result_of<_Fn(_A0),
2884                         is_class<typename remove_reference<_Fn>::type>::value ||
2885                         is_function<typename remove_pointer<typename remove_reference<_Fn>::type>::type>::value,
2886                         is_member_pointer<typename remove_reference<_Fn>::type>::value
2887                        >
2888{
2889};
2890
2891template <class _Fn, class _A0, class _A1>
2892class _LIBCPP_TEMPLATE_VIS result_of<_Fn(_A0, _A1)>
2893    : public __result_of<_Fn(_A0, _A1),
2894                         is_class<typename remove_reference<_Fn>::type>::value ||
2895                         is_function<typename remove_pointer<typename remove_reference<_Fn>::type>::type>::value,
2896                         is_member_pointer<typename remove_reference<_Fn>::type>::value
2897                        >
2898{
2899};
2900
2901template <class _Fn, class _A0, class _A1, class _A2>
2902class _LIBCPP_TEMPLATE_VIS result_of<_Fn(_A0, _A1, _A2)>
2903    : public __result_of<_Fn(_A0, _A1, _A2),
2904                         is_class<typename remove_reference<_Fn>::type>::value ||
2905                         is_function<typename remove_pointer<typename remove_reference<_Fn>::type>::type>::value,
2906                         is_member_pointer<typename remove_reference<_Fn>::type>::value
2907                        >
2908{
2909};
2910
2911#endif  // _LIBCPP_HAS_NO_VARIADICS
2912
2913// template <class T, class... Args> struct is_constructible;
2914
2915namespace __is_construct
2916{
2917struct __nat {};
2918}
2919
2920#if !defined(_LIBCPP_CXX03_LANG) && (!__has_feature(is_constructible) || \
2921    defined(_LIBCPP_TESTING_FALLBACK_IS_CONSTRUCTIBLE))
2922
2923template <class _Tp, class... _Args>
2924struct __libcpp_is_constructible;
2925
2926template <class _To, class _From>
2927struct __is_invalid_base_to_derived_cast {
2928  static_assert(is_reference<_To>::value, "Wrong specialization");
2929  using _RawFrom = __uncvref_t<_From>;
2930  using _RawTo = __uncvref_t<_To>;
2931  static const bool value = __lazy_and<
2932        __lazy_not<is_same<_RawFrom, _RawTo>>,
2933        is_base_of<_RawFrom, _RawTo>,
2934        __lazy_not<__libcpp_is_constructible<_RawTo, _From>>
2935  >::value;
2936};
2937
2938template <class _To, class _From>
2939struct __is_invalid_lvalue_to_rvalue_cast : false_type {
2940  static_assert(is_reference<_To>::value, "Wrong specialization");
2941};
2942
2943template <class _ToRef, class _FromRef>
2944struct __is_invalid_lvalue_to_rvalue_cast<_ToRef&&, _FromRef&> {
2945  using _RawFrom = __uncvref_t<_FromRef>;
2946  using _RawTo = __uncvref_t<_ToRef>;
2947  static const bool value = __lazy_and<
2948      __lazy_not<is_function<_RawTo>>,
2949      __lazy_or<
2950        is_same<_RawFrom, _RawTo>,
2951        is_base_of<_RawTo, _RawFrom>>
2952    >::value;
2953};
2954
2955struct __is_constructible_helper
2956{
2957    template <class _To>
2958    static void __eat(_To);
2959
2960    // This overload is needed to work around a Clang bug that disallows
2961    // static_cast<T&&>(e) for non-reference-compatible types.
2962    // Example: static_cast<int&&>(declval<double>());
2963    // NOTE: The static_cast implementation below is required to support
2964    //  classes with explicit conversion operators.
2965    template <class _To, class _From,
2966              class = decltype(__eat<_To>(_VSTD::declval<_From>()))>
2967    static true_type __test_cast(int);
2968
2969    template <class _To, class _From,
2970              class = decltype(static_cast<_To>(_VSTD::declval<_From>()))>
2971    static integral_constant<bool,
2972        !__is_invalid_base_to_derived_cast<_To, _From>::value &&
2973        !__is_invalid_lvalue_to_rvalue_cast<_To, _From>::value
2974    > __test_cast(long);
2975
2976    template <class, class>
2977    static false_type __test_cast(...);
2978
2979    template <class _Tp, class ..._Args,
2980        class = decltype(_Tp(_VSTD::declval<_Args>()...))>
2981    static true_type __test_nary(int);
2982    template <class _Tp, class...>
2983    static false_type __test_nary(...);
2984
2985    template <class _Tp, class _A0, class = decltype(::new _Tp(_VSTD::declval<_A0>()))>
2986    static is_destructible<_Tp> __test_unary(int);
2987    template <class, class>
2988    static false_type __test_unary(...);
2989};
2990
2991template <class _Tp, bool = is_void<_Tp>::value>
2992struct __is_default_constructible
2993    : decltype(__is_constructible_helper::__test_nary<_Tp>(0))
2994{};
2995
2996template <class _Tp>
2997struct __is_default_constructible<_Tp, true> : false_type {};
2998
2999template <class _Tp>
3000struct __is_default_constructible<_Tp[], false> : false_type {};
3001
3002template <class _Tp, size_t _Nx>
3003struct __is_default_constructible<_Tp[_Nx], false>
3004    : __is_default_constructible<typename remove_all_extents<_Tp>::type>  {};
3005
3006template <class _Tp, class... _Args>
3007struct __libcpp_is_constructible
3008{
3009  static_assert(sizeof...(_Args) > 1, "Wrong specialization");
3010  typedef decltype(__is_constructible_helper::__test_nary<_Tp, _Args...>(0))
3011      type;
3012};
3013
3014template <class _Tp>
3015struct __libcpp_is_constructible<_Tp> : __is_default_constructible<_Tp> {};
3016
3017template <class _Tp, class _A0>
3018struct __libcpp_is_constructible<_Tp, _A0>
3019    : public decltype(__is_constructible_helper::__test_unary<_Tp, _A0>(0))
3020{};
3021
3022template <class _Tp, class _A0>
3023struct __libcpp_is_constructible<_Tp&, _A0>
3024    : public decltype(__is_constructible_helper::
3025    __test_cast<_Tp&, _A0>(0))
3026{};
3027
3028template <class _Tp, class _A0>
3029struct __libcpp_is_constructible<_Tp&&, _A0>
3030    : public decltype(__is_constructible_helper::
3031    __test_cast<_Tp&&, _A0>(0))
3032{};
3033
3034#endif
3035
3036#if __has_feature(is_constructible)
3037template <class _Tp, class ..._Args>
3038struct _LIBCPP_TEMPLATE_VIS is_constructible
3039    : public integral_constant<bool, __is_constructible(_Tp, _Args...)>
3040    {};
3041#elif !defined(_LIBCPP_CXX03_LANG)
3042template <class _Tp, class... _Args>
3043struct _LIBCPP_TEMPLATE_VIS is_constructible
3044    : public __libcpp_is_constructible<_Tp, _Args...>::type {};
3045#else
3046// template <class T> struct is_constructible0;
3047
3048//      main is_constructible0 test
3049
3050template <class _Tp>
3051decltype((_Tp(), true_type()))
3052__is_constructible0_test(_Tp&);
3053
3054false_type
3055__is_constructible0_test(__any);
3056
3057template <class _Tp, class _A0>
3058decltype((_Tp(_VSTD::declval<_A0>()), true_type()))
3059__is_constructible1_test(_Tp&, _A0&);
3060
3061template <class _A0>
3062false_type
3063__is_constructible1_test(__any, _A0&);
3064
3065template <class _Tp, class _A0, class _A1>
3066decltype((_Tp(_VSTD::declval<_A0>(), _VSTD::declval<_A1>()), true_type()))
3067__is_constructible2_test(_Tp&, _A0&, _A1&);
3068
3069template <class _A0, class _A1>
3070false_type
3071__is_constructible2_test(__any, _A0&, _A1&);
3072
3073template <bool, class _Tp>
3074struct __is_constructible0_imp // false, _Tp is not a scalar
3075    : public common_type
3076             <
3077                 decltype(__is_constructible0_test(declval<_Tp&>()))
3078             >::type
3079    {};
3080
3081template <bool, class _Tp, class _A0>
3082struct __is_constructible1_imp // false, _Tp is not a scalar
3083    : public common_type
3084             <
3085                 decltype(__is_constructible1_test(declval<_Tp&>(), declval<_A0&>()))
3086             >::type
3087    {};
3088
3089template <bool, class _Tp, class _A0, class _A1>
3090struct __is_constructible2_imp // false, _Tp is not a scalar
3091    : public common_type
3092             <
3093                 decltype(__is_constructible2_test(declval<_Tp&>(), declval<_A0>(), declval<_A1>()))
3094             >::type
3095    {};
3096
3097//      handle scalars and reference types
3098
3099//      Scalars are default constructible, references are not
3100
3101template <class _Tp>
3102struct __is_constructible0_imp<true, _Tp>
3103    : public is_scalar<_Tp>
3104    {};
3105
3106template <class _Tp, class _A0>
3107struct __is_constructible1_imp<true, _Tp, _A0>
3108    : public is_convertible<_A0, _Tp>
3109    {};
3110
3111template <class _Tp, class _A0, class _A1>
3112struct __is_constructible2_imp<true, _Tp, _A0, _A1>
3113    : public false_type
3114    {};
3115
3116//      Treat scalars and reference types separately
3117
3118template <bool, class _Tp>
3119struct __is_constructible0_void_check
3120    : public __is_constructible0_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
3121                                _Tp>
3122    {};
3123
3124template <bool, class _Tp, class _A0>
3125struct __is_constructible1_void_check
3126    : public __is_constructible1_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
3127                                _Tp, _A0>
3128    {};
3129
3130template <bool, class _Tp, class _A0, class _A1>
3131struct __is_constructible2_void_check
3132    : public __is_constructible2_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
3133                                _Tp, _A0, _A1>
3134    {};
3135
3136//      If any of T or Args is void, is_constructible should be false
3137
3138template <class _Tp>
3139struct __is_constructible0_void_check<true, _Tp>
3140    : public false_type
3141    {};
3142
3143template <class _Tp, class _A0>
3144struct __is_constructible1_void_check<true, _Tp, _A0>
3145    : public false_type
3146    {};
3147
3148template <class _Tp, class _A0, class _A1>
3149struct __is_constructible2_void_check<true, _Tp, _A0, _A1>
3150    : public false_type
3151    {};
3152
3153//      is_constructible entry point
3154
3155template <class _Tp, class _A0 = __is_construct::__nat,
3156                     class _A1 = __is_construct::__nat>
3157struct _LIBCPP_TEMPLATE_VIS is_constructible
3158    : public __is_constructible2_void_check<is_void<_Tp>::value
3159                                        || is_abstract<_Tp>::value
3160                                        || is_function<_Tp>::value
3161                                        || is_void<_A0>::value
3162                                        || is_void<_A1>::value,
3163                                           _Tp, _A0, _A1>
3164    {};
3165
3166template <class _Tp>
3167struct _LIBCPP_TEMPLATE_VIS is_constructible<_Tp, __is_construct::__nat, __is_construct::__nat>
3168    : public __is_constructible0_void_check<is_void<_Tp>::value
3169                                        || is_abstract<_Tp>::value
3170                                        || is_function<_Tp>::value,
3171                                           _Tp>
3172    {};
3173
3174template <class _Tp, class _A0>
3175struct _LIBCPP_TEMPLATE_VIS is_constructible<_Tp, _A0, __is_construct::__nat>
3176    : public __is_constructible1_void_check<is_void<_Tp>::value
3177                                        || is_abstract<_Tp>::value
3178                                        || is_function<_Tp>::value
3179                                        || is_void<_A0>::value,
3180                                           _Tp, _A0>
3181    {};
3182
3183//      Array types are default constructible if their element type
3184//      is default constructible
3185
3186template <class _Ap, size_t _Np>
3187struct __is_constructible0_imp<false, _Ap[_Np]>
3188    : public is_constructible<typename remove_all_extents<_Ap>::type>
3189    {};
3190
3191template <class _Ap, size_t _Np, class _A0>
3192struct __is_constructible1_imp<false, _Ap[_Np], _A0>
3193    : public false_type
3194    {};
3195
3196template <class _Ap, size_t _Np, class _A0, class _A1>
3197struct __is_constructible2_imp<false, _Ap[_Np], _A0, _A1>
3198    : public false_type
3199    {};
3200
3201//      Incomplete array types are not constructible
3202
3203template <class _Ap>
3204struct __is_constructible0_imp<false, _Ap[]>
3205    : public false_type
3206    {};
3207
3208template <class _Ap, class _A0>
3209struct __is_constructible1_imp<false, _Ap[], _A0>
3210    : public false_type
3211    {};
3212
3213template <class _Ap, class _A0, class _A1>
3214struct __is_constructible2_imp<false, _Ap[], _A0, _A1>
3215    : public false_type
3216    {};
3217
3218#endif // __has_feature(is_constructible)
3219
3220
3221#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
3222template <class _Tp, class ..._Args> _LIBCPP_CONSTEXPR bool is_constructible_v
3223    = is_constructible<_Tp, _Args...>::value;
3224#endif
3225
3226// is_default_constructible
3227
3228template <class _Tp>
3229struct _LIBCPP_TEMPLATE_VIS is_default_constructible
3230    : public is_constructible<_Tp>
3231    {};
3232
3233#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3234template <class _Tp> _LIBCPP_CONSTEXPR bool is_default_constructible_v
3235    = is_default_constructible<_Tp>::value;
3236#endif
3237
3238// is_copy_constructible
3239
3240template <class _Tp>
3241struct _LIBCPP_TEMPLATE_VIS is_copy_constructible
3242    : public is_constructible<_Tp,
3243                  typename add_lvalue_reference<typename add_const<_Tp>::type>::type> {};
3244
3245#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3246template <class _Tp> _LIBCPP_CONSTEXPR bool is_copy_constructible_v
3247    = is_copy_constructible<_Tp>::value;
3248#endif
3249
3250// is_move_constructible
3251
3252template <class _Tp>
3253struct _LIBCPP_TEMPLATE_VIS is_move_constructible
3254#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3255    : public is_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
3256#else
3257    : public is_copy_constructible<_Tp>
3258#endif
3259    {};
3260
3261#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3262template <class _Tp> _LIBCPP_CONSTEXPR bool is_move_constructible_v
3263    = is_move_constructible<_Tp>::value;
3264#endif
3265
3266// is_trivially_constructible
3267
3268#ifndef _LIBCPP_HAS_NO_VARIADICS
3269
3270#if __has_feature(is_trivially_constructible) || _GNUC_VER >= 501
3271
3272template <class _Tp, class... _Args>
3273struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible
3274    : integral_constant<bool, __is_trivially_constructible(_Tp, _Args...)>
3275{
3276};
3277
3278#else  // !__has_feature(is_trivially_constructible)
3279
3280template <class _Tp, class... _Args>
3281struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible
3282    : false_type
3283{
3284};
3285
3286template <class _Tp>
3287struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp>
3288#if __has_feature(has_trivial_constructor) || (_GNUC_VER >= 403)
3289    : integral_constant<bool, __has_trivial_constructor(_Tp)>
3290#else
3291    : integral_constant<bool, is_scalar<_Tp>::value>
3292#endif
3293{
3294};
3295
3296template <class _Tp>
3297#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3298struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp&&>
3299#else
3300struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp>
3301#endif
3302    : integral_constant<bool, is_scalar<_Tp>::value>
3303{
3304};
3305
3306template <class _Tp>
3307struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, const _Tp&>
3308    : integral_constant<bool, is_scalar<_Tp>::value>
3309{
3310};
3311
3312template <class _Tp>
3313struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp&>
3314    : integral_constant<bool, is_scalar<_Tp>::value>
3315{
3316};
3317
3318#endif  // !__has_feature(is_trivially_constructible)
3319
3320#else  // _LIBCPP_HAS_NO_VARIADICS
3321
3322template <class _Tp, class _A0 = __is_construct::__nat,
3323                     class _A1 = __is_construct::__nat>
3324struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible
3325    : false_type
3326{
3327};
3328
3329#if __has_feature(is_trivially_constructible) || _GNUC_VER >= 501
3330
3331template <class _Tp>
3332struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, __is_construct::__nat,
3333                                                       __is_construct::__nat>
3334    : integral_constant<bool, __is_trivially_constructible(_Tp)>
3335{
3336};
3337
3338template <class _Tp>
3339struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp,
3340                                                       __is_construct::__nat>
3341    : integral_constant<bool, __is_trivially_constructible(_Tp, _Tp)>
3342{
3343};
3344
3345template <class _Tp>
3346struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, const _Tp&,
3347                                                       __is_construct::__nat>
3348    : integral_constant<bool, __is_trivially_constructible(_Tp, const _Tp&)>
3349{
3350};
3351
3352template <class _Tp>
3353struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp&,
3354                                                       __is_construct::__nat>
3355    : integral_constant<bool, __is_trivially_constructible(_Tp, _Tp&)>
3356{
3357};
3358
3359#else  // !__has_feature(is_trivially_constructible)
3360
3361template <class _Tp>
3362struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, __is_construct::__nat,
3363                                                       __is_construct::__nat>
3364    : integral_constant<bool, is_scalar<_Tp>::value>
3365{
3366};
3367
3368template <class _Tp>
3369struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp,
3370                                                       __is_construct::__nat>
3371    : integral_constant<bool, is_scalar<_Tp>::value>
3372{
3373};
3374
3375template <class _Tp>
3376struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, const _Tp&,
3377                                                       __is_construct::__nat>
3378    : integral_constant<bool, is_scalar<_Tp>::value>
3379{
3380};
3381
3382template <class _Tp>
3383struct _LIBCPP_TEMPLATE_VIS is_trivially_constructible<_Tp, _Tp&,
3384                                                       __is_construct::__nat>
3385    : integral_constant<bool, is_scalar<_Tp>::value>
3386{
3387};
3388
3389#endif  // !__has_feature(is_trivially_constructible)
3390
3391#endif  // _LIBCPP_HAS_NO_VARIADICS
3392
3393#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
3394template <class _Tp, class... _Args> _LIBCPP_CONSTEXPR bool is_trivially_constructible_v
3395    = is_trivially_constructible<_Tp, _Args...>::value;
3396#endif
3397
3398// is_trivially_default_constructible
3399
3400template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_default_constructible
3401    : public is_trivially_constructible<_Tp>
3402    {};
3403
3404#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3405template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_default_constructible_v
3406    = is_trivially_default_constructible<_Tp>::value;
3407#endif
3408
3409// is_trivially_copy_constructible
3410
3411template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_copy_constructible
3412    : public is_trivially_constructible<_Tp, typename add_lvalue_reference<const _Tp>::type>
3413    {};
3414
3415#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3416template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_copy_constructible_v
3417    = is_trivially_copy_constructible<_Tp>::value;
3418#endif
3419
3420// is_trivially_move_constructible
3421
3422template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_move_constructible
3423#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3424    : public is_trivially_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
3425#else
3426    : public is_trivially_copy_constructible<_Tp>
3427#endif
3428    {};
3429
3430#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3431template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_move_constructible_v
3432    = is_trivially_move_constructible<_Tp>::value;
3433#endif
3434
3435// is_trivially_assignable
3436
3437#if __has_feature(is_trivially_assignable) || _GNUC_VER >= 501
3438
3439template <class _Tp, class _Arg>
3440struct is_trivially_assignable
3441    : integral_constant<bool, __is_trivially_assignable(_Tp, _Arg)>
3442{
3443};
3444
3445#else  // !__has_feature(is_trivially_assignable)
3446
3447template <class _Tp, class _Arg>
3448struct is_trivially_assignable
3449    : public false_type {};
3450
3451template <class _Tp>
3452struct is_trivially_assignable<_Tp&, _Tp>
3453    : integral_constant<bool, is_scalar<_Tp>::value> {};
3454
3455template <class _Tp>
3456struct is_trivially_assignable<_Tp&, _Tp&>
3457    : integral_constant<bool, is_scalar<_Tp>::value> {};
3458
3459template <class _Tp>
3460struct is_trivially_assignable<_Tp&, const _Tp&>
3461    : integral_constant<bool, is_scalar<_Tp>::value> {};
3462
3463#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3464
3465template <class _Tp>
3466struct is_trivially_assignable<_Tp&, _Tp&&>
3467    : integral_constant<bool, is_scalar<_Tp>::value> {};
3468
3469#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3470
3471#endif  // !__has_feature(is_trivially_assignable)
3472
3473#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3474template <class _Tp, class _Arg> _LIBCPP_CONSTEXPR bool is_trivially_assignable_v
3475    = is_trivially_assignable<_Tp, _Arg>::value;
3476#endif
3477
3478// is_trivially_copy_assignable
3479
3480template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_copy_assignable
3481    : public is_trivially_assignable<typename add_lvalue_reference<_Tp>::type,
3482                  typename add_lvalue_reference<typename add_const<_Tp>::type>::type> {};
3483
3484#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3485template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_copy_assignable_v
3486    = is_trivially_copy_assignable<_Tp>::value;
3487#endif
3488
3489// is_trivially_move_assignable
3490
3491template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_move_assignable
3492    : public is_trivially_assignable<typename add_lvalue_reference<_Tp>::type,
3493#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3494                                     typename add_rvalue_reference<_Tp>::type>
3495#else
3496                                     typename add_lvalue_reference<_Tp>::type>
3497#endif
3498    {};
3499
3500#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3501template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_move_assignable_v
3502    = is_trivially_move_assignable<_Tp>::value;
3503#endif
3504
3505// is_trivially_destructible
3506
3507#if __has_feature(has_trivial_destructor) || (_GNUC_VER >= 403)
3508
3509template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
3510    : public integral_constant<bool, is_destructible<_Tp>::value && __has_trivial_destructor(_Tp)> {};
3511
3512#else
3513
3514template <class _Tp> struct __libcpp_trivial_destructor
3515    : public integral_constant<bool, is_scalar<_Tp>::value ||
3516                                     is_reference<_Tp>::value> {};
3517
3518template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible
3519    : public __libcpp_trivial_destructor<typename remove_all_extents<_Tp>::type> {};
3520
3521template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_destructible<_Tp[]>
3522    : public false_type {};
3523
3524#endif
3525
3526#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3527template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_destructible_v
3528    = is_trivially_destructible<_Tp>::value;
3529#endif
3530
3531// is_nothrow_constructible
3532
3533#if 0
3534template <class _Tp, class... _Args>
3535struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
3536    : public integral_constant<bool, __is_nothrow_constructible(_Tp(_Args...))>
3537{
3538};
3539
3540#else
3541
3542#ifndef _LIBCPP_HAS_NO_VARIADICS
3543
3544#if __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
3545
3546template <bool, bool, class _Tp, class... _Args> struct __libcpp_is_nothrow_constructible;
3547
3548template <class _Tp, class... _Args>
3549struct __libcpp_is_nothrow_constructible</*is constructible*/true, /*is reference*/false, _Tp, _Args...>
3550    : public integral_constant<bool, noexcept(_Tp(declval<_Args>()...))>
3551{
3552};
3553
3554template <class _Tp>
3555void __implicit_conversion_to(_Tp) noexcept { }
3556
3557template <class _Tp, class _Arg>
3558struct __libcpp_is_nothrow_constructible</*is constructible*/true, /*is reference*/true, _Tp, _Arg>
3559    : public integral_constant<bool, noexcept(__implicit_conversion_to<_Tp>(declval<_Arg>()))>
3560{
3561};
3562
3563template <class _Tp, bool _IsReference, class... _Args>
3564struct __libcpp_is_nothrow_constructible</*is constructible*/false, _IsReference, _Tp, _Args...>
3565    : public false_type
3566{
3567};
3568
3569template <class _Tp, class... _Args>
3570struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
3571    : __libcpp_is_nothrow_constructible<is_constructible<_Tp, _Args...>::value, is_reference<_Tp>::value, _Tp, _Args...>
3572{
3573};
3574
3575template <class _Tp, size_t _Ns>
3576struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp[_Ns]>
3577    : __libcpp_is_nothrow_constructible<is_constructible<_Tp>::value, is_reference<_Tp>::value, _Tp>
3578{
3579};
3580
3581#else  // __has_feature(cxx_noexcept)
3582
3583template <class _Tp, class... _Args>
3584struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
3585    : false_type
3586{
3587};
3588
3589template <class _Tp>
3590struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp>
3591#if __has_feature(has_nothrow_constructor) || (_GNUC_VER >= 403)
3592    : integral_constant<bool, __has_nothrow_constructor(_Tp)>
3593#else
3594    : integral_constant<bool, is_scalar<_Tp>::value>
3595#endif
3596{
3597};
3598
3599template <class _Tp>
3600#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3601struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _Tp&&>
3602#else
3603struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _Tp>
3604#endif
3605#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3606    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3607#else
3608    : integral_constant<bool, is_scalar<_Tp>::value>
3609#endif
3610{
3611};
3612
3613template <class _Tp>
3614struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, const _Tp&>
3615#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3616    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3617#else
3618    : integral_constant<bool, is_scalar<_Tp>::value>
3619#endif
3620{
3621};
3622
3623template <class _Tp>
3624struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _Tp&>
3625#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3626    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3627#else
3628    : integral_constant<bool, is_scalar<_Tp>::value>
3629#endif
3630{
3631};
3632
3633#endif  // __has_feature(cxx_noexcept)
3634
3635#else  // _LIBCPP_HAS_NO_VARIADICS
3636
3637template <class _Tp, class _A0 = __is_construct::__nat,
3638                     class _A1 = __is_construct::__nat>
3639struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
3640    : false_type
3641{
3642};
3643
3644template <class _Tp>
3645struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, __is_construct::__nat,
3646                                                       __is_construct::__nat>
3647#if __has_feature(has_nothrow_constructor) || (_GNUC_VER >= 403)
3648    : integral_constant<bool, __has_nothrow_constructor(_Tp)>
3649#else
3650    : integral_constant<bool, is_scalar<_Tp>::value>
3651#endif
3652{
3653};
3654
3655template <class _Tp>
3656struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _Tp,
3657                                                       __is_construct::__nat>
3658#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3659    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3660#else
3661    : integral_constant<bool, is_scalar<_Tp>::value>
3662#endif
3663{
3664};
3665
3666template <class _Tp>
3667struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, const _Tp&,
3668                                                       __is_construct::__nat>
3669#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3670    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3671#else
3672    : integral_constant<bool, is_scalar<_Tp>::value>
3673#endif
3674{
3675};
3676
3677template <class _Tp>
3678struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp, _Tp&,
3679                                                       __is_construct::__nat>
3680#if __has_feature(has_nothrow_copy) || (_GNUC_VER >= 403)
3681    : integral_constant<bool, __has_nothrow_copy(_Tp)>
3682#else
3683    : integral_constant<bool, is_scalar<_Tp>::value>
3684#endif
3685{
3686};
3687
3688#endif  // _LIBCPP_HAS_NO_VARIADICS
3689#endif  // __has_feature(is_nothrow_constructible)
3690
3691#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
3692template <class _Tp, class ..._Args> _LIBCPP_CONSTEXPR bool is_nothrow_constructible_v
3693    = is_nothrow_constructible<_Tp, _Args...>::value;
3694#endif
3695
3696// is_nothrow_default_constructible
3697
3698template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_default_constructible
3699    : public is_nothrow_constructible<_Tp>
3700    {};
3701
3702#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3703template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_default_constructible_v
3704    = is_nothrow_default_constructible<_Tp>::value;
3705#endif
3706
3707// is_nothrow_copy_constructible
3708
3709template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_constructible
3710    : public is_nothrow_constructible<_Tp,
3711                  typename add_lvalue_reference<typename add_const<_Tp>::type>::type> {};
3712
3713#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3714template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_copy_constructible_v
3715    = is_nothrow_copy_constructible<_Tp>::value;
3716#endif
3717
3718// is_nothrow_move_constructible
3719
3720template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_constructible
3721#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3722    : public is_nothrow_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
3723#else
3724    : public is_nothrow_copy_constructible<_Tp>
3725#endif
3726    {};
3727
3728#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3729template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_move_constructible_v
3730    = is_nothrow_move_constructible<_Tp>::value;
3731#endif
3732
3733// is_nothrow_assignable
3734
3735#if __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
3736
3737template <bool, class _Tp, class _Arg> struct __libcpp_is_nothrow_assignable;
3738
3739template <class _Tp, class _Arg>
3740struct __libcpp_is_nothrow_assignable<false, _Tp, _Arg>
3741    : public false_type
3742{
3743};
3744
3745template <class _Tp, class _Arg>
3746struct __libcpp_is_nothrow_assignable<true, _Tp, _Arg>
3747    : public integral_constant<bool, noexcept(_VSTD::declval<_Tp>() = _VSTD::declval<_Arg>()) >
3748{
3749};
3750
3751template <class _Tp, class _Arg>
3752struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable
3753    : public __libcpp_is_nothrow_assignable<is_assignable<_Tp, _Arg>::value, _Tp, _Arg>
3754{
3755};
3756
3757#else  // __has_feature(cxx_noexcept)
3758
3759template <class _Tp, class _Arg>
3760struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable
3761    : public false_type {};
3762
3763template <class _Tp>
3764struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable<_Tp&, _Tp>
3765#if __has_feature(has_nothrow_assign) || (_GNUC_VER >= 403)
3766    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
3767#else
3768    : integral_constant<bool, is_scalar<_Tp>::value> {};
3769#endif
3770
3771template <class _Tp>
3772struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable<_Tp&, _Tp&>
3773#if __has_feature(has_nothrow_assign) || (_GNUC_VER >= 403)
3774    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
3775#else
3776    : integral_constant<bool, is_scalar<_Tp>::value> {};
3777#endif
3778
3779template <class _Tp>
3780struct _LIBCPP_TEMPLATE_VIS is_nothrow_assignable<_Tp&, const _Tp&>
3781#if __has_feature(has_nothrow_assign) || (_GNUC_VER >= 403)
3782    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
3783#else
3784    : integral_constant<bool, is_scalar<_Tp>::value> {};
3785#endif
3786
3787#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3788
3789template <class _Tp>
3790struct is_nothrow_assignable<_Tp&, _Tp&&>
3791#if __has_feature(has_nothrow_assign) || (_GNUC_VER >= 403)
3792    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
3793#else
3794    : integral_constant<bool, is_scalar<_Tp>::value> {};
3795#endif
3796
3797#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3798
3799#endif  // __has_feature(cxx_noexcept)
3800
3801#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3802template <class _Tp, class _Arg> _LIBCPP_CONSTEXPR bool is_nothrow_assignable_v
3803    = is_nothrow_assignable<_Tp, _Arg>::value;
3804#endif
3805
3806// is_nothrow_copy_assignable
3807
3808template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_assignable
3809    : public is_nothrow_assignable<typename add_lvalue_reference<_Tp>::type,
3810                  typename add_lvalue_reference<typename add_const<_Tp>::type>::type> {};
3811
3812#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3813template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_copy_assignable_v
3814    = is_nothrow_copy_assignable<_Tp>::value;
3815#endif
3816
3817// is_nothrow_move_assignable
3818
3819template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_assignable
3820    : public is_nothrow_assignable<typename add_lvalue_reference<_Tp>::type,
3821#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3822                                     typename add_rvalue_reference<_Tp>::type>
3823#else
3824                                     typename add_lvalue_reference<_Tp>::type>
3825#endif
3826    {};
3827
3828#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3829template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_move_assignable_v
3830    = is_nothrow_move_assignable<_Tp>::value;
3831#endif
3832
3833// is_nothrow_destructible
3834
3835#if __has_feature(cxx_noexcept) || (_GNUC_VER >= 407 && __cplusplus >= 201103L)
3836
3837template <bool, class _Tp> struct __libcpp_is_nothrow_destructible;
3838
3839template <class _Tp>
3840struct __libcpp_is_nothrow_destructible<false, _Tp>
3841    : public false_type
3842{
3843};
3844
3845template <class _Tp>
3846struct __libcpp_is_nothrow_destructible<true, _Tp>
3847    : public integral_constant<bool, noexcept(_VSTD::declval<_Tp>().~_Tp()) >
3848{
3849};
3850
3851template <class _Tp>
3852struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible
3853    : public __libcpp_is_nothrow_destructible<is_destructible<_Tp>::value, _Tp>
3854{
3855};
3856
3857template <class _Tp, size_t _Ns>
3858struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp[_Ns]>
3859    : public is_nothrow_destructible<_Tp>
3860{
3861};
3862
3863template <class _Tp>
3864struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp&>
3865    : public true_type
3866{
3867};
3868
3869#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3870
3871template <class _Tp>
3872struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp&&>
3873    : public true_type
3874{
3875};
3876
3877#endif
3878
3879#else
3880
3881template <class _Tp> struct __libcpp_nothrow_destructor
3882    : public integral_constant<bool, is_scalar<_Tp>::value ||
3883                                     is_reference<_Tp>::value> {};
3884
3885template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible
3886    : public __libcpp_nothrow_destructor<typename remove_all_extents<_Tp>::type> {};
3887
3888template <class _Tp>
3889struct _LIBCPP_TEMPLATE_VIS is_nothrow_destructible<_Tp[]>
3890    : public false_type {};
3891
3892#endif
3893
3894#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3895template <class _Tp> _LIBCPP_CONSTEXPR bool is_nothrow_destructible_v
3896    = is_nothrow_destructible<_Tp>::value;
3897#endif
3898
3899// is_pod
3900
3901#if __has_feature(is_pod) || (_GNUC_VER >= 403)
3902
3903template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_pod
3904    : public integral_constant<bool, __is_pod(_Tp)> {};
3905
3906#else
3907
3908template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_pod
3909    : public integral_constant<bool, is_trivially_default_constructible<_Tp>::value   &&
3910                                     is_trivially_copy_constructible<_Tp>::value      &&
3911                                     is_trivially_copy_assignable<_Tp>::value    &&
3912                                     is_trivially_destructible<_Tp>::value> {};
3913
3914#endif
3915
3916#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3917template <class _Tp> _LIBCPP_CONSTEXPR bool is_pod_v
3918    = is_pod<_Tp>::value;
3919#endif
3920
3921// is_literal_type;
3922
3923template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_literal_type
3924#ifdef _LIBCPP_IS_LITERAL
3925    : public integral_constant<bool, _LIBCPP_IS_LITERAL(_Tp)>
3926#else
3927    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value ||
3928                              is_reference<typename remove_all_extents<_Tp>::type>::value>
3929#endif
3930    {};
3931
3932#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3933template <class _Tp> _LIBCPP_CONSTEXPR bool is_literal_type_v
3934    = is_literal_type<_Tp>::value;
3935#endif
3936
3937// is_standard_layout;
3938
3939template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_standard_layout
3940#if __has_feature(is_standard_layout) || (_GNUC_VER >= 407)
3941    : public integral_constant<bool, __is_standard_layout(_Tp)>
3942#else
3943    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value>
3944#endif
3945    {};
3946
3947#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3948template <class _Tp> _LIBCPP_CONSTEXPR bool is_standard_layout_v
3949    = is_standard_layout<_Tp>::value;
3950#endif
3951
3952// is_trivially_copyable;
3953
3954template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivially_copyable
3955#if __has_feature(is_trivially_copyable)
3956    : public integral_constant<bool, __is_trivially_copyable(_Tp)>
3957#elif _GNUC_VER >= 501
3958    : public integral_constant<bool, !is_volatile<_Tp>::value && __is_trivially_copyable(_Tp)>
3959#else
3960    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value>
3961#endif
3962    {};
3963
3964#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3965template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivially_copyable_v
3966    = is_trivially_copyable<_Tp>::value;
3967#endif
3968
3969// is_trivial;
3970
3971template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_trivial
3972#if __has_feature(is_trivial) || _GNUC_VER >= 407
3973    : public integral_constant<bool, __is_trivial(_Tp)>
3974#else
3975    : integral_constant<bool, is_trivially_copyable<_Tp>::value &&
3976                                 is_trivially_default_constructible<_Tp>::value>
3977#endif
3978    {};
3979
3980#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
3981template <class _Tp> _LIBCPP_CONSTEXPR bool is_trivial_v
3982    = is_trivial<_Tp>::value;
3983#endif
3984
3985template <class _Tp> struct __is_reference_wrapper_impl : public false_type {};
3986template <class _Tp> struct __is_reference_wrapper_impl<reference_wrapper<_Tp> > : public true_type {};
3987template <class _Tp> struct __is_reference_wrapper
3988    : public __is_reference_wrapper_impl<typename remove_cv<_Tp>::type> {};
3989
3990#ifndef _LIBCPP_CXX03_LANG
3991
3992// Check for complete types
3993
3994template <class ..._Tp> struct __check_complete;
3995
3996template <>
3997struct __check_complete<>
3998{
3999};
4000
4001template <class _Hp, class _T0, class ..._Tp>
4002struct __check_complete<_Hp, _T0, _Tp...>
4003    : private __check_complete<_Hp>,
4004      private __check_complete<_T0, _Tp...>
4005{
4006};
4007
4008template <class _Hp>
4009struct __check_complete<_Hp, _Hp>
4010    : private __check_complete<_Hp>
4011{
4012};
4013
4014template <class _Tp>
4015struct __check_complete<_Tp>
4016{
4017    static_assert(sizeof(_Tp) > 0, "Type must be complete.");
4018};
4019
4020template <class _Tp>
4021struct __check_complete<_Tp&>
4022    : private __check_complete<_Tp>
4023{
4024};
4025
4026template <class _Tp>
4027struct __check_complete<_Tp&&>
4028    : private __check_complete<_Tp>
4029{
4030};
4031
4032template <class _Rp, class ..._Param>
4033struct __check_complete<_Rp (*)(_Param...)>
4034    : private __check_complete<_Rp>
4035{
4036};
4037
4038template <class ..._Param>
4039struct __check_complete<void (*)(_Param...)>
4040{
4041};
4042
4043template <class _Rp, class ..._Param>
4044struct __check_complete<_Rp (_Param...)>
4045    : private __check_complete<_Rp>
4046{
4047};
4048
4049template <class ..._Param>
4050struct __check_complete<void (_Param...)>
4051{
4052};
4053
4054template <class _Rp, class _Class, class ..._Param>
4055struct __check_complete<_Rp (_Class::*)(_Param...)>
4056    : private __check_complete<_Class>
4057{
4058};
4059
4060template <class _Rp, class _Class, class ..._Param>
4061struct __check_complete<_Rp (_Class::*)(_Param...) const>
4062    : private __check_complete<_Class>
4063{
4064};
4065
4066template <class _Rp, class _Class, class ..._Param>
4067struct __check_complete<_Rp (_Class::*)(_Param...) volatile>
4068    : private __check_complete<_Class>
4069{
4070};
4071
4072template <class _Rp, class _Class, class ..._Param>
4073struct __check_complete<_Rp (_Class::*)(_Param...) const volatile>
4074    : private __check_complete<_Class>
4075{
4076};
4077
4078template <class _Rp, class _Class, class ..._Param>
4079struct __check_complete<_Rp (_Class::*)(_Param...) &>
4080    : private __check_complete<_Class>
4081{
4082};
4083
4084template <class _Rp, class _Class, class ..._Param>
4085struct __check_complete<_Rp (_Class::*)(_Param...) const&>
4086    : private __check_complete<_Class>
4087{
4088};
4089
4090template <class _Rp, class _Class, class ..._Param>
4091struct __check_complete<_Rp (_Class::*)(_Param...) volatile&>
4092    : private __check_complete<_Class>
4093{
4094};
4095
4096template <class _Rp, class _Class, class ..._Param>
4097struct __check_complete<_Rp (_Class::*)(_Param...) const volatile&>
4098    : private __check_complete<_Class>
4099{
4100};
4101
4102template <class _Rp, class _Class, class ..._Param>
4103struct __check_complete<_Rp (_Class::*)(_Param...) &&>
4104    : private __check_complete<_Class>
4105{
4106};
4107
4108template <class _Rp, class _Class, class ..._Param>
4109struct __check_complete<_Rp (_Class::*)(_Param...) const&&>
4110    : private __check_complete<_Class>
4111{
4112};
4113
4114template <class _Rp, class _Class, class ..._Param>
4115struct __check_complete<_Rp (_Class::*)(_Param...) volatile&&>
4116    : private __check_complete<_Class>
4117{
4118};
4119
4120template <class _Rp, class _Class, class ..._Param>
4121struct __check_complete<_Rp (_Class::*)(_Param...) const volatile&&>
4122    : private __check_complete<_Class>
4123{
4124};
4125
4126template <class _Rp, class _Class>
4127struct __check_complete<_Rp _Class::*>
4128    : private __check_complete<_Class>
4129{
4130};
4131
4132
4133template <class _Fp, class _A0,
4134         class _DecayFp = typename decay<_Fp>::type,
4135         class _DecayA0 = typename decay<_A0>::type,
4136         class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
4137using __enable_if_bullet1 = typename enable_if
4138    <
4139        is_member_function_pointer<_DecayFp>::value
4140        && is_base_of<_ClassT, _DecayA0>::value
4141    >::type;
4142
4143template <class _Fp, class _A0,
4144         class _DecayFp = typename decay<_Fp>::type,
4145         class _DecayA0 = typename decay<_A0>::type>
4146using __enable_if_bullet2 = typename enable_if
4147    <
4148        is_member_function_pointer<_DecayFp>::value
4149        && __is_reference_wrapper<_DecayA0>::value
4150    >::type;
4151
4152template <class _Fp, class _A0,
4153         class _DecayFp = typename decay<_Fp>::type,
4154         class _DecayA0 = typename decay<_A0>::type,
4155         class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
4156using __enable_if_bullet3 = typename enable_if
4157    <
4158        is_member_function_pointer<_DecayFp>::value
4159        && !is_base_of<_ClassT, _DecayA0>::value
4160        && !__is_reference_wrapper<_DecayA0>::value
4161    >::type;
4162
4163template <class _Fp, class _A0,
4164         class _DecayFp = typename decay<_Fp>::type,
4165         class _DecayA0 = typename decay<_A0>::type,
4166         class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
4167using __enable_if_bullet4 = typename enable_if
4168    <
4169        is_member_object_pointer<_DecayFp>::value
4170        && is_base_of<_ClassT, _DecayA0>::value
4171    >::type;
4172
4173template <class _Fp, class _A0,
4174         class _DecayFp = typename decay<_Fp>::type,
4175         class _DecayA0 = typename decay<_A0>::type>
4176using __enable_if_bullet5 = typename enable_if
4177    <
4178        is_member_object_pointer<_DecayFp>::value
4179        && __is_reference_wrapper<_DecayA0>::value
4180    >::type;
4181
4182template <class _Fp, class _A0,
4183         class _DecayFp = typename decay<_Fp>::type,
4184         class _DecayA0 = typename decay<_A0>::type,
4185         class _ClassT = typename __member_pointer_class_type<_DecayFp>::type>
4186using __enable_if_bullet6 = typename enable_if
4187    <
4188        is_member_object_pointer<_DecayFp>::value
4189        && !is_base_of<_ClassT, _DecayA0>::value
4190        && !__is_reference_wrapper<_DecayA0>::value
4191    >::type;
4192
4193// __invoke forward declarations
4194
4195// fall back - none of the bullets
4196
4197#define _LIBCPP_INVOKE_RETURN(...) \
4198    noexcept(noexcept(__VA_ARGS__)) -> decltype(__VA_ARGS__) \
4199    { return __VA_ARGS__; }
4200
4201template <class ..._Args>
4202auto __invoke(__any, _Args&& ...__args) -> __nat;
4203
4204template <class ..._Args>
4205auto __invoke_constexpr(__any, _Args&& ...__args) -> __nat;
4206
4207// bullets 1, 2 and 3
4208
4209template <class _Fp, class _A0, class ..._Args,
4210          class = __enable_if_bullet1<_Fp, _A0>>
4211inline _LIBCPP_INLINE_VISIBILITY
4212auto
4213__invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4214_LIBCPP_INVOKE_RETURN((_VSTD::forward<_A0>(__a0).*__f)(_VSTD::forward<_Args>(__args)...))
4215
4216template <class _Fp, class _A0, class ..._Args,
4217          class = __enable_if_bullet1<_Fp, _A0>>
4218inline _LIBCPP_INLINE_VISIBILITY
4219_LIBCPP_CONSTEXPR auto
4220__invoke_constexpr(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4221_LIBCPP_INVOKE_RETURN((_VSTD::forward<_A0>(__a0).*__f)(_VSTD::forward<_Args>(__args)...))
4222
4223template <class _Fp, class _A0, class ..._Args,
4224          class = __enable_if_bullet2<_Fp, _A0>>
4225inline _LIBCPP_INLINE_VISIBILITY
4226auto
4227__invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4228_LIBCPP_INVOKE_RETURN((__a0.get().*__f)(_VSTD::forward<_Args>(__args)...))
4229
4230template <class _Fp, class _A0, class ..._Args,
4231          class = __enable_if_bullet2<_Fp, _A0>>
4232inline _LIBCPP_INLINE_VISIBILITY
4233_LIBCPP_CONSTEXPR auto
4234__invoke_constexpr(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4235_LIBCPP_INVOKE_RETURN((__a0.get().*__f)(_VSTD::forward<_Args>(__args)...))
4236
4237template <class _Fp, class _A0, class ..._Args,
4238          class = __enable_if_bullet3<_Fp, _A0>>
4239inline _LIBCPP_INLINE_VISIBILITY
4240auto
4241__invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4242_LIBCPP_INVOKE_RETURN(((*_VSTD::forward<_A0>(__a0)).*__f)(_VSTD::forward<_Args>(__args)...))
4243
4244template <class _Fp, class _A0, class ..._Args,
4245          class = __enable_if_bullet3<_Fp, _A0>>
4246inline _LIBCPP_INLINE_VISIBILITY
4247_LIBCPP_CONSTEXPR auto
4248__invoke_constexpr(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
4249_LIBCPP_INVOKE_RETURN(((*_VSTD::forward<_A0>(__a0)).*__f)(_VSTD::forward<_Args>(__args)...))
4250
4251// bullets 4, 5 and 6
4252
4253template <class _Fp, class _A0,
4254          class = __enable_if_bullet4<_Fp, _A0>>
4255inline _LIBCPP_INLINE_VISIBILITY
4256auto
4257__invoke(_Fp&& __f, _A0&& __a0)
4258_LIBCPP_INVOKE_RETURN(_VSTD::forward<_A0>(__a0).*__f)
4259
4260template <class _Fp, class _A0,
4261          class = __enable_if_bullet4<_Fp, _A0>>
4262inline _LIBCPP_INLINE_VISIBILITY
4263_LIBCPP_CONSTEXPR auto
4264__invoke_constexpr(_Fp&& __f, _A0&& __a0)
4265_LIBCPP_INVOKE_RETURN(_VSTD::forward<_A0>(__a0).*__f)
4266
4267template <class _Fp, class _A0,
4268          class = __enable_if_bullet5<_Fp, _A0>>
4269inline _LIBCPP_INLINE_VISIBILITY
4270auto
4271__invoke(_Fp&& __f, _A0&& __a0)
4272_LIBCPP_INVOKE_RETURN(__a0.get().*__f)
4273
4274template <class _Fp, class _A0,
4275          class = __enable_if_bullet5<_Fp, _A0>>
4276inline _LIBCPP_INLINE_VISIBILITY
4277_LIBCPP_CONSTEXPR auto
4278__invoke_constexpr(_Fp&& __f, _A0&& __a0)
4279_LIBCPP_INVOKE_RETURN(__a0.get().*__f)
4280
4281template <class _Fp, class _A0,
4282          class = __enable_if_bullet6<_Fp, _A0>>
4283inline _LIBCPP_INLINE_VISIBILITY
4284auto
4285__invoke(_Fp&& __f, _A0&& __a0)
4286_LIBCPP_INVOKE_RETURN((*_VSTD::forward<_A0>(__a0)).*__f)
4287
4288template <class _Fp, class _A0,
4289          class = __enable_if_bullet6<_Fp, _A0>>
4290inline _LIBCPP_INLINE_VISIBILITY
4291_LIBCPP_CONSTEXPR auto
4292__invoke_constexpr(_Fp&& __f, _A0&& __a0)
4293_LIBCPP_INVOKE_RETURN((*_VSTD::forward<_A0>(__a0)).*__f)
4294
4295// bullet 7
4296
4297template <class _Fp, class ..._Args>
4298inline _LIBCPP_INLINE_VISIBILITY
4299auto
4300__invoke(_Fp&& __f, _Args&& ...__args)
4301_LIBCPP_INVOKE_RETURN(_VSTD::forward<_Fp>(__f)(_VSTD::forward<_Args>(__args)...))
4302
4303template <class _Fp, class ..._Args>
4304inline _LIBCPP_INLINE_VISIBILITY
4305_LIBCPP_CONSTEXPR auto
4306__invoke_constexpr(_Fp&& __f, _Args&& ...__args)
4307_LIBCPP_INVOKE_RETURN(_VSTD::forward<_Fp>(__f)(_VSTD::forward<_Args>(__args)...))
4308
4309#undef _LIBCPP_INVOKE_RETURN
4310
4311// __invokable
4312
4313template <class _Ret, class _Fp, class ..._Args>
4314struct __invokable_r
4315    : private __check_complete<_Fp>
4316{
4317    using _Result = decltype(
4318        _VSTD::__invoke(_VSTD::declval<_Fp>(), _VSTD::declval<_Args>()...));
4319
4320    static const bool value =
4321        conditional<
4322            !is_same<_Result, __nat>::value,
4323            typename conditional<
4324                is_void<_Ret>::value,
4325                true_type,
4326                is_convertible<_Result, _Ret>
4327            >::type,
4328            false_type
4329        >::type::value;
4330};
4331
4332template <class _Fp, class ..._Args>
4333using __invokable = __invokable_r<void, _Fp, _Args...>;
4334
4335template <bool _IsInvokable, bool _IsCVVoid, class _Ret, class _Fp, class ..._Args>
4336struct __nothrow_invokable_r_imp {
4337  static const bool value = false;
4338};
4339
4340template <class _Ret, class _Fp, class ..._Args>
4341struct __nothrow_invokable_r_imp<true, false, _Ret, _Fp, _Args...>
4342{
4343    typedef __nothrow_invokable_r_imp _ThisT;
4344
4345    template <class _Tp>
4346    static void __test_noexcept(_Tp) noexcept;
4347
4348    static const bool value = noexcept(_ThisT::__test_noexcept<_Ret>(
4349        _VSTD::__invoke(_VSTD::declval<_Fp>(), _VSTD::declval<_Args>()...)));
4350};
4351
4352template <class _Ret, class _Fp, class ..._Args>
4353struct __nothrow_invokable_r_imp<true, true, _Ret, _Fp, _Args...>
4354{
4355    static const bool value = noexcept(
4356        _VSTD::__invoke(_VSTD::declval<_Fp>(), _VSTD::declval<_Args>()...));
4357};
4358
4359template <class _Ret, class _Fp, class ..._Args>
4360using __nothrow_invokable_r =
4361    __nothrow_invokable_r_imp<
4362            __invokable_r<_Ret, _Fp, _Args...>::value,
4363            is_void<_Ret>::value,
4364            _Ret, _Fp, _Args...
4365    >;
4366
4367template <class _Fp, class ..._Args>
4368struct __invoke_of
4369    : public enable_if<
4370        __invokable<_Fp, _Args...>::value,
4371        typename __invokable_r<void, _Fp, _Args...>::_Result>
4372{
4373};
4374
4375// result_of
4376
4377template <class _Fp, class ..._Args>
4378class _LIBCPP_TEMPLATE_VIS result_of<_Fp(_Args...)>
4379    : public __invoke_of<_Fp, _Args...>
4380{
4381};
4382
4383#if _LIBCPP_STD_VER > 11
4384template <class _Tp> using result_of_t = typename result_of<_Tp>::type;
4385#endif
4386
4387#if _LIBCPP_STD_VER > 14
4388
4389// is_callable
4390
4391template <class _Fn, class _Ret = void>
4392struct _LIBCPP_TEMPLATE_VIS is_callable;
4393
4394template <class _Fn, class ..._Args, class _Ret>
4395struct _LIBCPP_TEMPLATE_VIS is_callable<_Fn(_Args...), _Ret>
4396    : integral_constant<bool, __invokable_r<_Ret, _Fn, _Args...>::value> {};
4397
4398template <class _Fn, class _Ret = void>
4399constexpr bool is_callable_v = is_callable<_Fn, _Ret>::value;
4400
4401// is_nothrow_callable
4402
4403template <class _Fn, class _Ret = void>
4404struct _LIBCPP_TEMPLATE_VIS is_nothrow_callable;
4405
4406template <class _Fn, class ..._Args, class _Ret>
4407struct _LIBCPP_TEMPLATE_VIS is_nothrow_callable<_Fn(_Args...), _Ret>
4408    : integral_constant<bool, __nothrow_invokable_r<_Ret, _Fn, _Args...>::value>
4409{};
4410
4411template <class _Fn, class _Ret = void>
4412constexpr bool is_nothrow_callable_v = is_nothrow_callable<_Fn, _Ret>::value;
4413
4414#endif // _LIBCPP_STD_VER > 14
4415
4416#endif  // !defined(_LIBCPP_CXX03_LANG)
4417
4418template <class _Tp> struct __is_swappable;
4419template <class _Tp> struct __is_nothrow_swappable;
4420
4421template <class _Tp>
4422inline _LIBCPP_INLINE_VISIBILITY
4423#ifndef _LIBCPP_CXX03_LANG
4424typename enable_if
4425<
4426    is_move_constructible<_Tp>::value &&
4427    is_move_assignable<_Tp>::value
4428>::type
4429#else
4430void
4431#endif
4432swap(_Tp& __x, _Tp& __y) _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value &&
4433                                    is_nothrow_move_assignable<_Tp>::value)
4434{
4435    _Tp __t(_VSTD::move(__x));
4436    __x = _VSTD::move(__y);
4437    __y = _VSTD::move(__t);
4438}
4439
4440template<class _Tp, size_t _Np>
4441inline _LIBCPP_INLINE_VISIBILITY
4442typename enable_if<
4443    __is_swappable<_Tp>::value
4444>::type
4445swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value);
4446
4447template <class _ForwardIterator1, class _ForwardIterator2>
4448inline _LIBCPP_INLINE_VISIBILITY
4449void
4450iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
4451    //                                  _NOEXCEPT_(_NOEXCEPT_(swap(*__a, *__b)))
4452               _NOEXCEPT_(_NOEXCEPT_(swap(*_VSTD::declval<_ForwardIterator1>(),
4453                                          *_VSTD::declval<_ForwardIterator2>())))
4454{
4455    swap(*__a, *__b);
4456}
4457
4458// __swappable
4459
4460namespace __detail
4461{
4462// ALL generic swap overloads MUST already have a declaration available at this point.
4463
4464template <class _Tp, class _Up = _Tp,
4465          bool _NotVoid = !is_void<_Tp>::value && !is_void<_Up>::value>
4466struct __swappable_with
4467{
4468    template <class _LHS, class _RHS>
4469    static decltype(swap(_VSTD::declval<_LHS>(), _VSTD::declval<_RHS>()))
4470    __test_swap(int);
4471    template <class, class>
4472    static __nat __test_swap(long);
4473
4474    // Extra parens are needed for the C++03 definition of decltype.
4475    typedef decltype((__test_swap<_Tp, _Up>(0))) __swap1;
4476    typedef decltype((__test_swap<_Up, _Tp>(0))) __swap2;
4477
4478    static const bool value = !is_same<__swap1, __nat>::value
4479                           && !is_same<__swap2, __nat>::value;
4480};
4481
4482template <class _Tp, class _Up>
4483struct __swappable_with<_Tp, _Up,  false> : false_type {};
4484
4485template <class _Tp, class _Up = _Tp, bool _Swappable = __swappable_with<_Tp, _Up>::value>
4486struct __nothrow_swappable_with {
4487  static const bool value =
4488#ifndef _LIBCPP_HAS_NO_NOEXCEPT
4489      noexcept(swap(_VSTD::declval<_Tp>(), _VSTD::declval<_Up>()))
4490  &&  noexcept(swap(_VSTD::declval<_Up>(), _VSTD::declval<_Tp>()));
4491#else
4492      false;
4493#endif
4494};
4495
4496template <class _Tp, class _Up>
4497struct __nothrow_swappable_with<_Tp, _Up, false> : false_type {};
4498
4499}  // __detail
4500
4501template <class _Tp>
4502struct __is_swappable
4503    : public integral_constant<bool, __detail::__swappable_with<_Tp&>::value>
4504{
4505};
4506
4507template <class _Tp>
4508struct __is_nothrow_swappable
4509    : public integral_constant<bool, __detail::__nothrow_swappable_with<_Tp&>::value>
4510{
4511};
4512
4513#if _LIBCPP_STD_VER > 14
4514
4515template <class _Tp, class _Up>
4516struct _LIBCPP_TEMPLATE_VIS is_swappable_with
4517    : public integral_constant<bool, __detail::__swappable_with<_Tp, _Up>::value>
4518{
4519};
4520
4521template <class _Tp>
4522struct _LIBCPP_TEMPLATE_VIS is_swappable
4523    : public conditional<
4524        __is_referenceable<_Tp>::value,
4525        is_swappable_with<
4526            typename add_lvalue_reference<_Tp>::type,
4527            typename add_lvalue_reference<_Tp>::type>,
4528        false_type
4529    >::type
4530{
4531};
4532
4533template <class _Tp, class _Up>
4534struct _LIBCPP_TEMPLATE_VIS is_nothrow_swappable_with
4535    : public integral_constant<bool, __detail::__nothrow_swappable_with<_Tp, _Up>::value>
4536{
4537};
4538
4539template <class _Tp>
4540struct _LIBCPP_TEMPLATE_VIS is_nothrow_swappable
4541    : public conditional<
4542        __is_referenceable<_Tp>::value,
4543        is_nothrow_swappable_with<
4544            typename add_lvalue_reference<_Tp>::type,
4545            typename add_lvalue_reference<_Tp>::type>,
4546        false_type
4547    >::type
4548{
4549};
4550
4551template <class _Tp, class _Up>
4552constexpr bool is_swappable_with_v = is_swappable_with<_Tp, _Up>::value;
4553
4554template <class _Tp>
4555constexpr bool is_swappable_v = is_swappable<_Tp>::value;
4556
4557template <class _Tp, class _Up>
4558constexpr bool is_nothrow_swappable_with_v = is_nothrow_swappable_with<_Tp, _Up>::value;
4559
4560template <class _Tp>
4561constexpr bool is_nothrow_swappable_v = is_nothrow_swappable<_Tp>::value;
4562
4563#endif // _LIBCPP_STD_VER > 14
4564
4565#ifdef _LIBCPP_UNDERLYING_TYPE
4566
4567template <class _Tp>
4568struct underlying_type
4569{
4570    typedef _LIBCPP_UNDERLYING_TYPE(_Tp) type;
4571};
4572
4573#if _LIBCPP_STD_VER > 11
4574template <class _Tp> using underlying_type_t = typename underlying_type<_Tp>::type;
4575#endif
4576
4577#else  // _LIBCPP_UNDERLYING_TYPE
4578
4579template <class _Tp, bool _Support = false>
4580struct underlying_type
4581{
4582    static_assert(_Support, "The underyling_type trait requires compiler "
4583                            "support. Either no such support exists or "
4584                            "libc++ does not know how to use it.");
4585};
4586
4587#endif // _LIBCPP_UNDERLYING_TYPE
4588
4589
4590template <class _Tp, bool = is_enum<_Tp>::value>
4591struct __sfinae_underlying_type
4592{
4593    typedef typename underlying_type<_Tp>::type type;
4594    typedef decltype(((type)1) + 0) __promoted_type;
4595};
4596
4597template <class _Tp>
4598struct __sfinae_underlying_type<_Tp, false> {};
4599
4600inline _LIBCPP_INLINE_VISIBILITY
4601int __convert_to_integral(int __val) { return __val; }
4602
4603inline _LIBCPP_INLINE_VISIBILITY
4604unsigned __convert_to_integral(unsigned __val) { return __val; }
4605
4606inline _LIBCPP_INLINE_VISIBILITY
4607long __convert_to_integral(long __val) { return __val; }
4608
4609inline _LIBCPP_INLINE_VISIBILITY
4610unsigned long __convert_to_integral(unsigned long __val) { return __val; }
4611
4612inline _LIBCPP_INLINE_VISIBILITY
4613long long __convert_to_integral(long long __val) { return __val; }
4614
4615inline _LIBCPP_INLINE_VISIBILITY
4616unsigned long long __convert_to_integral(unsigned long long __val) {return __val; }
4617
4618#ifndef _LIBCPP_HAS_NO_INT128
4619inline _LIBCPP_INLINE_VISIBILITY
4620__int128_t __convert_to_integral(__int128_t __val) { return __val; }
4621
4622inline _LIBCPP_INLINE_VISIBILITY
4623__uint128_t __convert_to_integral(__uint128_t __val) { return __val; }
4624#endif
4625
4626template <class _Tp>
4627inline _LIBCPP_INLINE_VISIBILITY
4628typename __sfinae_underlying_type<_Tp>::__promoted_type
4629__convert_to_integral(_Tp __val) { return __val; }
4630
4631#ifndef _LIBCPP_CXX03_LANG
4632
4633template <class _Tp>
4634struct __has_operator_addressof_member_imp
4635{
4636    template <class _Up>
4637        static auto __test(int)
4638            -> typename __select_2nd<decltype(_VSTD::declval<_Up>().operator&()), true_type>::type;
4639    template <class>
4640        static auto __test(long) -> false_type;
4641
4642    static const bool value = decltype(__test<_Tp>(0))::value;
4643};
4644
4645template <class _Tp>
4646struct __has_operator_addressof_free_imp
4647{
4648    template <class _Up>
4649        static auto __test(int)
4650            -> typename __select_2nd<decltype(operator&(_VSTD::declval<_Up>())), true_type>::type;
4651    template <class>
4652        static auto __test(long) -> false_type;
4653
4654    static const bool value = decltype(__test<_Tp>(0))::value;
4655};
4656
4657template <class _Tp>
4658struct __has_operator_addressof
4659    : public integral_constant<bool, __has_operator_addressof_member_imp<_Tp>::value
4660                                  || __has_operator_addressof_free_imp<_Tp>::value>
4661{};
4662
4663#endif  // _LIBCPP_CXX03_LANG
4664
4665#if _LIBCPP_STD_VER > 14
4666
4667#define __cpp_lib_void_t 201411
4668template <class...> using void_t = void;
4669
4670# ifndef _LIBCPP_HAS_NO_VARIADICS
4671template <class... _Args>
4672struct conjunction : __and_<_Args...> {};
4673template<class... _Args> constexpr bool conjunction_v = conjunction<_Args...>::value;
4674
4675template <class... _Args>
4676struct disjunction : __or_<_Args...> {};
4677template<class... _Args> constexpr bool disjunction_v = disjunction<_Args...>::value;
4678
4679template <class _Tp>
4680struct negation : __not_<_Tp> {};
4681template<class _Tp> constexpr bool negation_v = negation<_Tp>::value;
4682# endif // _LIBCPP_HAS_NO_VARIADICS
4683#endif  // _LIBCPP_STD_VER > 14
4684
4685// These traits are used in __tree and __hash_table
4686#ifndef _LIBCPP_CXX03_LANG
4687struct __extract_key_fail_tag {};
4688struct __extract_key_self_tag {};
4689struct __extract_key_first_tag {};
4690
4691template <class _ValTy, class _Key,
4692          class _RawValTy = typename __unconstref<_ValTy>::type>
4693struct __can_extract_key
4694    : conditional<is_same<_RawValTy, _Key>::value, __extract_key_self_tag,
4695                  __extract_key_fail_tag>::type {};
4696
4697template <class _Pair, class _Key, class _First, class _Second>
4698struct __can_extract_key<_Pair, _Key, pair<_First, _Second>>
4699    : conditional<is_same<typename remove_const<_First>::type, _Key>::value,
4700                  __extract_key_first_tag, __extract_key_fail_tag>::type {};
4701
4702// __can_extract_map_key uses true_type/false_type instead of the tags.
4703// It returns true if _Key != _ContainerValueTy (the container is a map not a set)
4704// and _ValTy == _Key.
4705template <class _ValTy, class _Key, class _ContainerValueTy,
4706          class _RawValTy = typename __unconstref<_ValTy>::type>
4707struct __can_extract_map_key
4708    : integral_constant<bool, is_same<_RawValTy, _Key>::value> {};
4709
4710// This specialization returns __extract_key_fail_tag for non-map containers
4711// because _Key == _ContainerValueTy
4712template <class _ValTy, class _Key, class _RawValTy>
4713struct __can_extract_map_key<_ValTy, _Key, _Key, _RawValTy>
4714    : false_type {};
4715
4716#endif
4717
4718_LIBCPP_END_NAMESPACE_STD
4719
4720#endif  // _LIBCPP_TYPE_TRAITS
4721