type_traits revision 241903
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;
23    typedef integral_constant<bool, false> false_type;
24
25    // helper traits
26    template <bool, class T = void> struct enable_if;
27    template <bool, class T, class F> struct conditional;
28
29    // Primary classification traits:
30    template <class T> struct is_void;
31    template <class T> struct is_integral;
32    template <class T> struct is_floating_point;
33    template <class T> struct is_array;
34    template <class T> struct is_pointer;
35    template <class T> struct is_lvalue_reference;
36    template <class T> struct is_rvalue_reference;
37    template <class T> struct is_member_object_pointer;
38    template <class T> struct is_member_function_pointer;
39    template <class T> struct is_enum;
40    template <class T> struct is_union;
41    template <class T> struct is_class;
42    template <class T> struct is_function;
43
44    // Secondary classification traits:
45    template <class T> struct is_reference;
46    template <class T> struct is_arithmetic;
47    template <class T> struct is_fundamental;
48    template <class T> struct is_member_pointer;
49    template <class T> struct is_scalar;
50    template <class T> struct is_object;
51    template <class T> struct is_compound;
52
53    // Const-volatile properties and transformations:
54    template <class T> struct is_const;
55    template <class T> struct is_volatile;
56    template <class T> struct remove_const;
57    template <class T> struct remove_volatile;
58    template <class T> struct remove_cv;
59    template <class T> struct add_const;
60    template <class T> struct add_volatile;
61    template <class T> struct add_cv;
62
63    // Reference transformations:
64    template <class T> struct remove_reference;
65    template <class T> struct add_lvalue_reference;
66    template <class T> struct add_rvalue_reference;
67
68    // Pointer transformations:
69    template <class T> struct remove_pointer;
70    template <class T> struct add_pointer;
71
72    // Integral properties:
73    template <class T> struct is_signed;
74    template <class T> struct is_unsigned;
75    template <class T> struct make_signed;
76    template <class T> struct make_unsigned;
77
78    // Array properties and transformations:
79    template <class T> struct rank;
80    template <class T, unsigned I = 0> struct extent;
81    template <class T> struct remove_extent;
82    template <class T> struct remove_all_extents;
83
84    // Member introspection:
85    template <class T> struct is_pod;
86    template <class T> struct is_trivial;
87    template <class T> struct is_trivially_copyable;
88    template <class T> struct is_standard_layout;
89    template <class T> struct is_literal_type;
90    template <class T> struct is_empty;
91    template <class T> struct is_polymorphic;
92    template <class T> struct is_abstract;
93
94    template <class T, class... Args> struct is_constructible;
95    template <class T>                struct is_default_constructible;
96    template <class T>                struct is_copy_constructible;
97    template <class T>                struct is_move_constructible;
98    template <class T, class U>       struct is_assignable;
99    template <class T>                struct is_copy_assignable;
100    template <class T>                struct is_move_assignable;
101    template <class T>                struct is_destructible;
102
103    template <class T, class... Args> struct is_trivially_constructible;
104    template <class T>                struct is_trivially_default_constructible;
105    template <class T>                struct is_trivially_copy_constructible;
106    template <class T>                struct is_trivially_move_constructible;
107    template <class T, class U>       struct is_trivially_assignable;
108    template <class T>                struct is_trivially_copy_assignable;
109    template <class T>                struct is_trivially_move_assignable;
110    template <class T>                struct is_trivially_destructible;
111
112    template <class T, class... Args> struct is_nothrow_constructible;
113    template <class T>                struct is_nothrow_default_constructible;
114    template <class T>                struct is_nothrow_copy_constructible;
115    template <class T>                struct is_nothrow_move_constructible;
116    template <class T, class U>       struct is_nothrow_assignable;
117    template <class T>                struct is_nothrow_copy_assignable;
118    template <class T>                struct is_nothrow_move_assignable;
119    template <class T>                struct is_nothrow_destructible;
120
121    template <class T> struct has_virtual_destructor;
122
123    // Relationships between types:
124    template <class T, class U> struct is_same;
125    template <class Base, class Derived> struct is_base_of;
126    template <class From, class To> struct is_convertible;
127
128    // Alignment properties and transformations:
129    template <class T> struct alignment_of;
130    template <size_t Len, size_t Align = most_stringent_alignment_requirement>
131        struct aligned_storage;
132
133    template <class T> struct decay;
134    template <class... T> struct common_type;
135    template <class T> struct underlying_type;
136    template <class> class result_of; // undefined
137    template <class Fn, class... ArgTypes> class result_of<Fn(ArgTypes...)>;
138
139}  // std
140
141*/
142#include <__config>
143#include <cstddef>
144
145#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
146#pragma GCC system_header
147#endif
148
149_LIBCPP_BEGIN_NAMESPACE_STD
150
151template <bool _Bp, class _If, class _Then>
152    struct _LIBCPP_VISIBLE conditional {typedef _If type;};
153template <class _If, class _Then>
154    struct _LIBCPP_VISIBLE conditional<false, _If, _Then> {typedef _Then type;};
155
156template <bool, class _Tp = void> struct _LIBCPP_VISIBLE enable_if {};
157template <class _Tp> struct _LIBCPP_VISIBLE enable_if<true, _Tp> {typedef _Tp type;};
158
159struct __two {char _[2];};
160
161// helper class:
162
163template <class _Tp, _Tp __v>
164struct _LIBCPP_VISIBLE integral_constant
165{
166    static _LIBCPP_CONSTEXPR const _Tp      value = __v;
167    typedef _Tp               value_type;
168    typedef integral_constant type;
169    _LIBCPP_INLINE_VISIBILITY
170        _LIBCPP_CONSTEXPR operator value_type() const {return value;}
171};
172
173template <class _Tp, _Tp __v>
174_LIBCPP_CONSTEXPR const _Tp integral_constant<_Tp, __v>::value;
175
176typedef integral_constant<bool, true>  true_type;
177typedef integral_constant<bool, false> false_type;
178
179// is_const
180
181template <class _Tp> struct _LIBCPP_VISIBLE is_const            : public false_type {};
182template <class _Tp> struct _LIBCPP_VISIBLE is_const<_Tp const> : public true_type {};
183
184// is_volatile
185
186template <class _Tp> struct _LIBCPP_VISIBLE is_volatile               : public false_type {};
187template <class _Tp> struct _LIBCPP_VISIBLE is_volatile<_Tp volatile> : public true_type {};
188
189// remove_const
190
191template <class _Tp> struct _LIBCPP_VISIBLE remove_const            {typedef _Tp type;};
192template <class _Tp> struct _LIBCPP_VISIBLE remove_const<const _Tp> {typedef _Tp type;};
193
194// remove_volatile
195
196template <class _Tp> struct _LIBCPP_VISIBLE remove_volatile               {typedef _Tp type;};
197template <class _Tp> struct _LIBCPP_VISIBLE remove_volatile<volatile _Tp> {typedef _Tp type;};
198
199// remove_cv
200
201template <class _Tp> struct _LIBCPP_VISIBLE remove_cv
202{typedef typename remove_volatile<typename remove_const<_Tp>::type>::type type;};
203
204// is_void
205
206template <class _Tp> struct __is_void       : public false_type {};
207template <>          struct __is_void<void> : public true_type {};
208
209template <class _Tp> struct _LIBCPP_VISIBLE is_void
210    : public __is_void<typename remove_cv<_Tp>::type> {};
211
212// __is_nullptr_t
213
214template <class _Tp> struct ____is_nullptr_t       : public false_type {};
215template <>          struct ____is_nullptr_t<nullptr_t> : public true_type {};
216
217template <class _Tp> struct _LIBCPP_VISIBLE __is_nullptr_t
218    : public ____is_nullptr_t<typename remove_cv<_Tp>::type> {};
219
220// is_integral
221
222template <class _Tp> struct __is_integral                     : public false_type {};
223template <>          struct __is_integral<bool>               : public true_type {};
224template <>          struct __is_integral<char>               : public true_type {};
225template <>          struct __is_integral<signed char>        : public true_type {};
226template <>          struct __is_integral<unsigned char>      : public true_type {};
227template <>          struct __is_integral<wchar_t>            : public true_type {};
228#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
229template <>          struct __is_integral<char16_t>           : public true_type {};
230template <>          struct __is_integral<char32_t>           : public true_type {};
231#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
232template <>          struct __is_integral<short>              : public true_type {};
233template <>          struct __is_integral<unsigned short>     : public true_type {};
234template <>          struct __is_integral<int>                : public true_type {};
235template <>          struct __is_integral<unsigned int>       : public true_type {};
236template <>          struct __is_integral<long>               : public true_type {};
237template <>          struct __is_integral<unsigned long>      : public true_type {};
238template <>          struct __is_integral<long long>          : public true_type {};
239template <>          struct __is_integral<unsigned long long> : public true_type {};
240
241template <class _Tp> struct _LIBCPP_VISIBLE is_integral
242    : public __is_integral<typename remove_cv<_Tp>::type> {};
243
244// is_floating_point
245
246template <class _Tp> struct __is_floating_point              : public false_type {};
247template <>          struct __is_floating_point<float>       : public true_type {};
248template <>          struct __is_floating_point<double>      : public true_type {};
249template <>          struct __is_floating_point<long double> : public true_type {};
250
251template <class _Tp> struct _LIBCPP_VISIBLE is_floating_point
252    : public __is_floating_point<typename remove_cv<_Tp>::type> {};
253
254// is_array
255
256template <class _Tp> struct _LIBCPP_VISIBLE is_array
257    : public false_type {};
258template <class _Tp> struct _LIBCPP_VISIBLE is_array<_Tp[]>
259    : public true_type {};
260template <class _Tp, size_t _Np> struct _LIBCPP_VISIBLE is_array<_Tp[_Np]>
261    : public true_type {};
262
263// is_pointer
264
265template <class _Tp> struct __is_pointer       : public false_type {};
266template <class _Tp> struct __is_pointer<_Tp*> : public true_type {};
267
268template <class _Tp> struct _LIBCPP_VISIBLE is_pointer
269    : public __is_pointer<typename remove_cv<_Tp>::type> {};
270
271// is_reference
272
273template <class _Tp> struct _LIBCPP_VISIBLE is_lvalue_reference       : public false_type {};
274template <class _Tp> struct _LIBCPP_VISIBLE is_lvalue_reference<_Tp&> : public true_type {};
275
276template <class _Tp> struct _LIBCPP_VISIBLE is_rvalue_reference        : public false_type {};
277#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
278template <class _Tp> struct _LIBCPP_VISIBLE is_rvalue_reference<_Tp&&> : public true_type {};
279#endif
280
281template <class _Tp> struct _LIBCPP_VISIBLE is_reference        : public false_type {};
282template <class _Tp> struct _LIBCPP_VISIBLE is_reference<_Tp&>  : public true_type {};
283#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
284template <class _Tp> struct _LIBCPP_VISIBLE is_reference<_Tp&&> : public true_type {};
285#endif
286
287#if defined(__clang__) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
288#define _LIBCPP_HAS_TYPE_TRAITS
289#endif
290
291// is_union
292
293#if __has_feature(is_union) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
294
295template <class _Tp> struct _LIBCPP_VISIBLE is_union
296    : public integral_constant<bool, __is_union(_Tp)> {};
297
298#else
299
300template <class _Tp> struct __libcpp_union : public false_type {};
301template <class _Tp> struct _LIBCPP_VISIBLE is_union
302    : public __libcpp_union<typename remove_cv<_Tp>::type> {};
303
304#endif
305
306// is_class
307
308#if __has_feature(is_class) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
309
310template <class _Tp> struct _LIBCPP_VISIBLE is_class
311    : public integral_constant<bool, __is_class(_Tp)> {};
312
313#else
314
315namespace __is_class_imp
316{
317template <class _Tp> char  __test(int _Tp::*);
318template <class _Tp> __two __test(...);
319}
320
321template <class _Tp> struct _LIBCPP_VISIBLE is_class
322    : public integral_constant<bool, sizeof(__is_class_imp::__test<_Tp>(0)) == 1 && !is_union<_Tp>::value> {};
323
324#endif
325
326// is_same
327
328template <class _Tp, class _Up> struct _LIBCPP_VISIBLE is_same           : public false_type {};
329template <class _Tp>            struct _LIBCPP_VISIBLE is_same<_Tp, _Tp> : public true_type {};
330
331// is_function
332
333namespace __is_function_imp
334{
335template <class _Tp> char  __test(_Tp*);
336template <class _Tp> __two __test(...);
337template <class _Tp> _Tp&  __source();
338}
339
340template <class _Tp, bool = is_class<_Tp>::value ||
341                            is_union<_Tp>::value ||
342                            is_void<_Tp>::value  ||
343                            is_reference<_Tp>::value ||
344                            is_same<_Tp, nullptr_t>::value >
345struct __is_function
346    : public integral_constant<bool, sizeof(__is_function_imp::__test<_Tp>(__is_function_imp::__source<_Tp>())) == 1>
347    {};
348template <class _Tp> struct __is_function<_Tp, true> : public false_type {};
349
350template <class _Tp> struct _LIBCPP_VISIBLE is_function
351    : public __is_function<_Tp> {};
352
353// is_member_function_pointer
354
355template <class _Tp> struct            __is_member_function_pointer             : public false_type {};
356template <class _Tp, class _Up> struct __is_member_function_pointer<_Tp _Up::*> : public is_function<_Tp> {};
357
358template <class _Tp> struct _LIBCPP_VISIBLE is_member_function_pointer
359    : public __is_member_function_pointer<typename remove_cv<_Tp>::type> {};
360
361// is_member_pointer
362
363template <class _Tp>            struct __is_member_pointer             : public false_type {};
364template <class _Tp, class _Up> struct __is_member_pointer<_Tp _Up::*> : public true_type {};
365
366template <class _Tp> struct _LIBCPP_VISIBLE is_member_pointer
367    : public __is_member_pointer<typename remove_cv<_Tp>::type> {};
368
369// is_member_object_pointer
370
371template <class _Tp> struct _LIBCPP_VISIBLE is_member_object_pointer
372    : public integral_constant<bool, is_member_pointer<_Tp>::value &&
373                                    !is_member_function_pointer<_Tp>::value> {};
374
375// is_enum
376
377#if __has_feature(is_enum) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
378
379template <class _Tp> struct _LIBCPP_VISIBLE is_enum
380    : public integral_constant<bool, __is_enum(_Tp)> {};
381
382#else
383
384template <class _Tp> struct _LIBCPP_VISIBLE is_enum
385    : public integral_constant<bool, !is_void<_Tp>::value             &&
386                                     !is_integral<_Tp>::value         &&
387                                     !is_floating_point<_Tp>::value   &&
388                                     !is_array<_Tp>::value            &&
389                                     !is_pointer<_Tp>::value          &&
390                                     !is_reference<_Tp>::value        &&
391                                     !is_member_pointer<_Tp>::value   &&
392                                     !is_union<_Tp>::value            &&
393                                     !is_class<_Tp>::value            &&
394                                     !is_function<_Tp>::value         > {};
395
396#endif
397
398// is_arithmetic
399
400template <class _Tp> struct _LIBCPP_VISIBLE is_arithmetic
401    : public integral_constant<bool, is_integral<_Tp>::value      ||
402                                     is_floating_point<_Tp>::value> {};
403
404// is_fundamental
405
406template <class _Tp> struct _LIBCPP_VISIBLE is_fundamental
407    : public integral_constant<bool, is_void<_Tp>::value        ||
408                                     __is_nullptr_t<_Tp>::value ||
409                                     is_arithmetic<_Tp>::value> {};
410
411// is_scalar
412
413template <class _Tp> struct _LIBCPP_VISIBLE is_scalar
414    : public integral_constant<bool, is_arithmetic<_Tp>::value     ||
415                                     is_member_pointer<_Tp>::value ||
416                                     is_pointer<_Tp>::value        ||
417                                     __is_nullptr_t<_Tp>::value    ||
418                                     is_enum<_Tp>::value           > {};
419
420template <> struct _LIBCPP_VISIBLE is_scalar<nullptr_t> : public true_type {};
421
422// is_object
423
424template <class _Tp> struct _LIBCPP_VISIBLE is_object
425    : public integral_constant<bool, is_scalar<_Tp>::value ||
426                                     is_array<_Tp>::value  ||
427                                     is_union<_Tp>::value  ||
428                                     is_class<_Tp>::value  > {};
429
430// is_compound
431
432template <class _Tp> struct _LIBCPP_VISIBLE is_compound
433    : public integral_constant<bool, !is_fundamental<_Tp>::value> {};
434
435// add_const
436
437template <class _Tp, bool = is_reference<_Tp>::value ||
438                            is_function<_Tp>::value  ||
439                            is_const<_Tp>::value     >
440struct __add_const             {typedef _Tp type;};
441
442template <class _Tp>
443struct __add_const<_Tp, false> {typedef const _Tp type;};
444
445template <class _Tp> struct _LIBCPP_VISIBLE add_const
446    {typedef typename __add_const<_Tp>::type type;};
447
448// add_volatile
449
450template <class _Tp, bool = is_reference<_Tp>::value ||
451                            is_function<_Tp>::value  ||
452                            is_volatile<_Tp>::value  >
453struct __add_volatile             {typedef _Tp type;};
454
455template <class _Tp>
456struct __add_volatile<_Tp, false> {typedef volatile _Tp type;};
457
458template <class _Tp> struct _LIBCPP_VISIBLE add_volatile
459    {typedef typename __add_volatile<_Tp>::type type;};
460
461// add_cv
462
463template <class _Tp> struct _LIBCPP_VISIBLE add_cv
464    {typedef typename add_const<typename add_volatile<_Tp>::type>::type type;};
465
466// remove_reference
467
468template <class _Tp> struct _LIBCPP_VISIBLE remove_reference        {typedef _Tp type;};
469template <class _Tp> struct _LIBCPP_VISIBLE remove_reference<_Tp&>  {typedef _Tp type;};
470#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
471template <class _Tp> struct _LIBCPP_VISIBLE remove_reference<_Tp&&> {typedef _Tp type;};
472#endif
473
474// add_lvalue_reference
475
476template <class _Tp> struct _LIBCPP_VISIBLE add_lvalue_reference                      {typedef _Tp& type;};
477template <class _Tp> struct _LIBCPP_VISIBLE add_lvalue_reference<_Tp&>                {typedef _Tp& type;};  // for older compiler
478template <>          struct _LIBCPP_VISIBLE add_lvalue_reference<void>                {typedef void type;};
479template <>          struct _LIBCPP_VISIBLE add_lvalue_reference<const void>          {typedef const void type;};
480template <>          struct _LIBCPP_VISIBLE add_lvalue_reference<volatile void>       {typedef volatile void type;};
481template <>          struct _LIBCPP_VISIBLE add_lvalue_reference<const volatile void> {typedef const volatile void type;};
482
483#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
484
485template <class _Tp> struct _LIBCPP_VISIBLE  add_rvalue_reference                     {typedef _Tp&& type;};
486template <>          struct _LIBCPP_VISIBLE add_rvalue_reference<void>                {typedef void type;};
487template <>          struct _LIBCPP_VISIBLE add_rvalue_reference<const void>          {typedef const void type;};
488template <>          struct _LIBCPP_VISIBLE add_rvalue_reference<volatile void>       {typedef volatile void type;};
489template <>          struct _LIBCPP_VISIBLE add_rvalue_reference<const volatile void> {typedef const volatile void type;};
490
491#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
492
493#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
494
495template <class _Tp>
496typename add_rvalue_reference<_Tp>::type
497declval() _NOEXCEPT;
498
499#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
500
501template <class _Tp>
502typename add_lvalue_reference<_Tp>::type
503declval();
504
505#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
506
507struct __any
508{
509    __any(...);
510};
511
512// remove_pointer
513
514template <class _Tp> struct _LIBCPP_VISIBLE remove_pointer                      {typedef _Tp type;};
515template <class _Tp> struct _LIBCPP_VISIBLE remove_pointer<_Tp*>                {typedef _Tp type;};
516template <class _Tp> struct _LIBCPP_VISIBLE remove_pointer<_Tp* const>          {typedef _Tp type;};
517template <class _Tp> struct _LIBCPP_VISIBLE remove_pointer<_Tp* volatile>       {typedef _Tp type;};
518template <class _Tp> struct _LIBCPP_VISIBLE remove_pointer<_Tp* const volatile> {typedef _Tp type;};
519
520// add_pointer
521
522template <class _Tp> struct _LIBCPP_VISIBLE add_pointer
523    {typedef typename remove_reference<_Tp>::type* type;};
524
525// is_signed
526
527template <class _Tp, bool = is_integral<_Tp>::value>
528struct ___is_signed : public integral_constant<bool, _Tp(-1) < _Tp(0)> {};
529
530template <class _Tp>
531struct ___is_signed<_Tp, false> : public true_type {};  // floating point
532
533template <class _Tp, bool = is_arithmetic<_Tp>::value>
534struct __is_signed : public ___is_signed<_Tp> {};
535
536template <class _Tp> struct __is_signed<_Tp, false> : public false_type {};
537
538template <class _Tp> struct _LIBCPP_VISIBLE is_signed : public __is_signed<_Tp> {};
539
540// is_unsigned
541
542template <class _Tp, bool = is_integral<_Tp>::value>
543struct ___is_unsigned : public integral_constant<bool, _Tp(0) < _Tp(-1)> {};
544
545template <class _Tp>
546struct ___is_unsigned<_Tp, false> : public false_type {};  // floating point
547
548template <class _Tp, bool = is_arithmetic<_Tp>::value>
549struct __is_unsigned : public ___is_unsigned<_Tp> {};
550
551template <class _Tp> struct __is_unsigned<_Tp, false> : public false_type {};
552
553template <class _Tp> struct _LIBCPP_VISIBLE is_unsigned : public __is_unsigned<_Tp> {};
554
555// rank
556
557template <class _Tp> struct _LIBCPP_VISIBLE rank
558    : public integral_constant<size_t, 0> {};
559template <class _Tp> struct _LIBCPP_VISIBLE rank<_Tp[]>
560    : public integral_constant<size_t, rank<_Tp>::value + 1> {};
561template <class _Tp, size_t _Np> struct _LIBCPP_VISIBLE rank<_Tp[_Np]>
562    : public integral_constant<size_t, rank<_Tp>::value + 1> {};
563
564// extent
565
566template <class _Tp, unsigned _Ip = 0> struct _LIBCPP_VISIBLE extent
567    : public integral_constant<size_t, 0> {};
568template <class _Tp> struct _LIBCPP_VISIBLE extent<_Tp[], 0>
569    : public integral_constant<size_t, 0> {};
570template <class _Tp, unsigned _Ip> struct _LIBCPP_VISIBLE extent<_Tp[], _Ip>
571    : public integral_constant<size_t, extent<_Tp, _Ip-1>::value> {};
572template <class _Tp, size_t _Np> struct _LIBCPP_VISIBLE extent<_Tp[_Np], 0>
573    : public integral_constant<size_t, _Np> {};
574template <class _Tp, size_t _Np, unsigned _Ip> struct _LIBCPP_VISIBLE extent<_Tp[_Np], _Ip>
575    : public integral_constant<size_t, extent<_Tp, _Ip-1>::value> {};
576
577// remove_extent
578
579template <class _Tp> struct _LIBCPP_VISIBLE remove_extent
580    {typedef _Tp type;};
581template <class _Tp> struct _LIBCPP_VISIBLE remove_extent<_Tp[]>
582    {typedef _Tp type;};
583template <class _Tp, size_t _Np> struct _LIBCPP_VISIBLE remove_extent<_Tp[_Np]>
584    {typedef _Tp type;};
585
586// remove_all_extents
587
588template <class _Tp> struct _LIBCPP_VISIBLE remove_all_extents
589    {typedef _Tp type;};
590template <class _Tp> struct _LIBCPP_VISIBLE remove_all_extents<_Tp[]>
591    {typedef typename remove_all_extents<_Tp>::type type;};
592template <class _Tp, size_t _Np> struct _LIBCPP_VISIBLE remove_all_extents<_Tp[_Np]>
593    {typedef typename remove_all_extents<_Tp>::type type;};
594
595// is_abstract
596
597namespace __is_abstract_imp
598{
599template <class _Tp> char  __test(_Tp (*)[1]);
600template <class _Tp> __two __test(...);
601}
602
603template <class _Tp, bool = is_class<_Tp>::value>
604struct __libcpp_abstract : public integral_constant<bool, sizeof(__is_abstract_imp::__test<_Tp>(0)) != 1> {};
605
606template <class _Tp> struct __libcpp_abstract<_Tp, false> : public false_type {};
607
608template <class _Tp> struct _LIBCPP_VISIBLE is_abstract : public __libcpp_abstract<_Tp> {};
609
610// is_base_of
611
612#ifdef _LIBCP_HAS_IS_BASE_OF
613
614template <class _Bp, class _Dp>
615struct _LIBCPP_VISIBLE is_base_of
616    : public integral_constant<bool, __is_base_of(_Bp, _Dp)> {};
617
618#else  // __has_feature(is_base_of)
619
620#error is_base_of not implemented.
621
622#endif  // __has_feature(is_base_of)
623
624// is_convertible
625
626#if __has_feature(is_convertible_to)
627
628template <class _T1, class _T2> struct _LIBCPP_VISIBLE is_convertible
629    : public integral_constant<bool, __is_convertible_to(_T1, _T2) &&
630                                     !is_abstract<_T2>::value> {};
631
632#else  // __has_feature(is_convertible_to)
633
634namespace __is_convertible_imp
635{
636template <class _Tp> char  __test(_Tp);
637template <class _Tp> __two __test(...);
638#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
639template <class _Tp> _Tp&& __source();
640#else
641template <class _Tp> typename remove_reference<_Tp>::type& __source();
642#endif
643
644template <class _Tp, bool _IsArray =    is_array<_Tp>::value,
645                     bool _IsFunction = is_function<_Tp>::value,
646                     bool _IsVoid =     is_void<_Tp>::value>
647                     struct __is_array_function_or_void                          {enum {value = 0};};
648template <class _Tp> struct __is_array_function_or_void<_Tp, true, false, false> {enum {value = 1};};
649template <class _Tp> struct __is_array_function_or_void<_Tp, false, true, false> {enum {value = 2};};
650template <class _Tp> struct __is_array_function_or_void<_Tp, false, false, true> {enum {value = 3};};
651}
652
653template <class _Tp,
654    unsigned = __is_convertible_imp::__is_array_function_or_void<typename remove_reference<_Tp>::type>::value>
655struct __is_convertible_check
656{
657    static const size_t __v = 0;
658};
659
660template <class _Tp>
661struct __is_convertible_check<_Tp, 0>
662{
663    static const size_t __v = sizeof(_Tp);
664};
665
666template <class _T1, class _T2,
667    unsigned _T1_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T1>::value,
668    unsigned _T2_is_array_function_or_void = __is_convertible_imp::__is_array_function_or_void<_T2>::value>
669struct __is_convertible
670    : public integral_constant<bool,
671#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
672        sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1
673#else
674        sizeof(__is_convertible_imp::__test<_T2>(__is_convertible_imp::__source<_T1>())) == 1
675         && !(!is_function<_T1>::value && !is_reference<_T1>::value && is_reference<_T2>::value
676              && (!is_const<typename remove_reference<_T2>::type>::value
677                  || is_volatile<typename remove_reference<_T2>::type>::value)
678                  && (is_same<typename remove_cv<_T1>::type,
679                              typename remove_cv<typename remove_reference<_T2>::type>::type>::value
680                      || is_base_of<typename remove_reference<_T2>::type, _T1>::value))
681#endif
682    >
683{};
684
685template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 0> : false_type {};
686
687template <class _T1> struct __is_convertible<_T1, const _T1&, 1, 0> : true_type {};
688#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
689template <class _T1> struct __is_convertible<_T1, _T1&&, 1, 0> : true_type {};
690template <class _T1> struct __is_convertible<_T1, const _T1&&, 1, 0> : true_type {};
691template <class _T1> struct __is_convertible<_T1, volatile _T1&&, 1, 0> : true_type {};
692template <class _T1> struct __is_convertible<_T1, const volatile _T1&&, 1, 0> : true_type {};
693#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
694
695template <class _T1, class _T2> struct __is_convertible<_T1, _T2*, 1, 0>
696    : public integral_constant<bool, __is_convertible<typename remove_all_extents<_T1>::type*, _T2*>::value> {};
697
698template <class _T1, class _T2> struct __is_convertible<_T1, _T2* const, 1, 0>
699    : public integral_constant<bool, __is_convertible<typename remove_all_extents<_T1>::type*, _T2*const>::value> {};
700
701template <class _T1, class _T2> struct __is_convertible<_T1, _T2* volatile, 1, 0>
702    : public integral_constant<bool, __is_convertible<typename remove_all_extents<_T1>::type*, _T2*volatile>::value> {};
703
704template <class _T1, class _T2> struct __is_convertible<_T1, _T2* const volatile, 1, 0>
705    : public integral_constant<bool, __is_convertible<typename remove_all_extents<_T1>::type*, _T2*const volatile>::value> {};
706
707template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 0>                : public false_type {};
708#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
709template <class _T1>            struct __is_convertible<_T1, _T1&&, 2, 0>               : public true_type {};
710#endif
711template <class _T1>            struct __is_convertible<_T1, _T1&, 2, 0>               : public true_type {};
712template <class _T1>            struct __is_convertible<_T1, _T1*, 2, 0>               : public true_type {};
713template <class _T1>            struct __is_convertible<_T1, _T1*const, 2, 0>          : public true_type {};
714template <class _T1>            struct __is_convertible<_T1, _T1*volatile, 2, 0>       : public true_type {};
715template <class _T1>            struct __is_convertible<_T1, _T1*const volatile, 2, 0> : public true_type {};
716
717template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 0> : public false_type {};
718
719template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 1> : public false_type {};
720template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 1> : public false_type {};
721template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 1> : public false_type {};
722template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 1> : public false_type {};
723
724template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 2> : public false_type {};
725template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 2> : public false_type {};
726template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 2> : public false_type {};
727template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 2> : public false_type {};
728
729template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 0, 3> : public false_type {};
730template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 1, 3> : public false_type {};
731template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 2, 3> : public false_type {};
732template <class _T1, class _T2> struct __is_convertible<_T1, _T2, 3, 3> : public true_type {};
733
734template <class _T1, class _T2> struct _LIBCPP_VISIBLE is_convertible
735    : public __is_convertible<_T1, _T2>
736{
737    static const size_t __complete_check1 = __is_convertible_check<_T1>::__v;
738    static const size_t __complete_check2 = __is_convertible_check<_T2>::__v;
739};
740
741#endif  // __has_feature(is_convertible_to)
742
743// is_empty
744
745#if __has_feature(is_empty)
746
747template <class _Tp>
748struct _LIBCPP_VISIBLE is_empty
749    : public integral_constant<bool, __is_empty(_Tp)> {};
750
751#else  // __has_feature(is_empty)
752
753template <class _Tp>
754struct __is_empty1
755    : public _Tp
756{
757    double _;
758};
759
760struct __is_empty2
761{
762    double _;
763};
764
765template <class _Tp, bool = is_class<_Tp>::value>
766struct __libcpp_empty : public integral_constant<bool, sizeof(__is_empty1<_Tp>) == sizeof(__is_empty2)> {};
767
768template <class _Tp> struct __libcpp_empty<_Tp, false> : public false_type {};
769
770template <class _Tp> struct _LIBCPP_VISIBLE is_empty : public __libcpp_empty<_Tp> {};
771
772#endif  // __has_feature(is_empty)
773
774// is_polymorphic
775
776#if __has_feature(is_polymorphic)
777
778template <class _Tp>
779struct _LIBCPP_VISIBLE is_polymorphic
780    : public integral_constant<bool, __is_polymorphic(_Tp)> {};
781
782#else
783
784template <class _Tp> struct __is_polymorphic1 : public _Tp {};
785template <class _Tp> struct __is_polymorphic2 : public _Tp {virtual ~__is_polymorphic2() throw();};
786
787template <class _Tp, bool = is_class<_Tp>::value>
788struct __libcpp_polymorphic
789    : public integral_constant<bool, sizeof(__is_polymorphic1<_Tp>) == sizeof(__is_polymorphic2<_Tp>)> {};
790
791template <class _Tp> struct __libcpp_polymorphic<_Tp, false> : public false_type {};
792
793template <class _Tp> struct _LIBCPP_VISIBLE is_polymorphic
794    : public __libcpp_polymorphic<_Tp> {};
795
796#endif // __has_feature(is_polymorphic)
797
798// has_virtual_destructor
799
800#if __has_feature(has_virtual_destructor) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
801
802template <class _Tp> struct _LIBCPP_VISIBLE has_virtual_destructor
803    : public integral_constant<bool, __has_virtual_destructor(_Tp)> {};
804
805#else  // _LIBCPP_HAS_TYPE_TRAITS
806
807template <class _Tp> struct _LIBCPP_VISIBLE has_virtual_destructor
808    : public false_type {};
809
810#endif  // _LIBCPP_HAS_TYPE_TRAITS
811
812// alignment_of
813
814template <class _Tp> struct __alignment_of {_Tp _;};
815
816template <class _Tp> struct _LIBCPP_VISIBLE alignment_of
817    : public integral_constant<size_t, __alignof__(__alignment_of<typename remove_all_extents<_Tp>::type>)> {};
818
819// aligned_storage
820
821template <class _Hp, class _Tp>
822struct __type_list
823{
824    typedef _Hp _Head;
825    typedef _Tp _Tail;
826};
827
828struct __nat
829{
830#ifndef _LIBCPP_HAS_NO_DELETED_FUNCTIONS
831    __nat() = delete;
832    __nat(const __nat&) = delete;
833    __nat& operator=(const __nat&) = delete;
834    ~__nat() = delete;
835#endif
836};
837
838template <class _Tp>
839struct __align_type
840{
841    static const size_t value = alignment_of<_Tp>::value;
842    typedef _Tp type;
843};
844
845struct __struct_double {long double _;};
846struct __struct_double4 {double _[4];};
847
848typedef
849    __type_list<__align_type<unsigned char>,
850    __type_list<__align_type<unsigned short>,
851    __type_list<__align_type<unsigned int>,
852    __type_list<__align_type<unsigned long>,
853    __type_list<__align_type<unsigned long long>,
854    __type_list<__align_type<double>,
855    __type_list<__align_type<long double>,
856    __type_list<__align_type<__struct_double>,
857    __type_list<__align_type<__struct_double4>,
858    __type_list<__align_type<int*>,
859    __nat
860    > > > > > > > > > > __all_types;
861
862template <class _TL, size_t _Align> struct __find_pod;
863
864template <class _Hp, size_t _Align>
865struct __find_pod<__type_list<_Hp, __nat>, _Align>
866{
867    typedef typename conditional<
868                             _Align == _Hp::value,
869                             typename _Hp::type,
870                             void
871                         >::type type;
872};
873
874template <class _Hp, class _Tp, size_t _Align>
875struct __find_pod<__type_list<_Hp, _Tp>, _Align>
876{
877    typedef typename conditional<
878                             _Align == _Hp::value,
879                             typename _Hp::type,
880                             typename __find_pod<_Tp, _Align>::type
881                         >::type type;
882};
883
884template <class _TL, size_t _Len> struct __find_max_align;
885
886template <class _Hp, size_t _Len>
887struct __find_max_align<__type_list<_Hp, __nat>, _Len> : public integral_constant<size_t, _Hp::value> {};
888
889template <size_t _Len, size_t _A1, size_t _A2>
890struct __select_align
891{
892private:
893    static const size_t __min = _A2 < _A1 ? _A2 : _A1;
894    static const size_t __max = _A1 < _A2 ? _A2 : _A1;
895public:
896    static const size_t value = _Len < __max ? __min : __max;
897};
898
899template <class _Hp, class _Tp, size_t _Len>
900struct __find_max_align<__type_list<_Hp, _Tp>, _Len>
901    : public integral_constant<size_t, __select_align<_Len, _Hp::value, __find_max_align<_Tp, _Len>::value>::value> {};
902
903template <size_t _Len, const size_t _Align = __find_max_align<__all_types, _Len>::value>
904struct _LIBCPP_VISIBLE aligned_storage
905{
906    typedef typename __find_pod<__all_types, _Align>::type _Aligner;
907    static_assert(!is_void<_Aligner>::value, "");
908    union type
909    {
910        _Aligner __align;
911        unsigned char __data[_Len];
912    };
913};
914
915#define _CREATE_ALIGNED_STORAGE_SPECIALIZATION(n) \
916template <size_t _Len>\
917struct _LIBCPP_VISIBLE aligned_storage<_Len, n>\
918{\
919    struct _ALIGNAS(n) type\
920    {\
921        unsigned char _[_Len];\
922    };\
923}
924
925_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1);
926_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2);
927_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4);
928_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x8);
929_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x10);
930_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x20);
931_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x40);
932_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x80);
933_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x100);
934_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x200);
935_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x400);
936_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x800);
937_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x1000);
938_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x2000);
939// MSDN says that MSVC does not support alignment beyond 8192 (=0x2000)
940#if !defined(_MSC_VER)
941_CREATE_ALIGNED_STORAGE_SPECIALIZATION(0x4000);
942#endif // !_MSC_VER
943
944#undef _CREATE_ALIGNED_STORAGE_SPECIALIZATION
945
946// __promote
947
948template <class _A1, class _A2 = void, class _A3 = void,
949          bool = (is_arithmetic<_A1>::value || is_void<_A1>::value) &&
950                 (is_arithmetic<_A2>::value || is_void<_A2>::value) &&
951                 (is_arithmetic<_A3>::value || is_void<_A3>::value)>
952class __promote {};
953
954template <class _A1, class _A2, class _A3>
955class __promote<_A1, _A2, _A3, true>
956{
957private:
958    typedef typename __promote<_A1>::type __type1;
959    typedef typename __promote<_A2>::type __type2;
960    typedef typename __promote<_A3>::type __type3;
961public:
962    typedef decltype(__type1() + __type2() + __type3()) type;
963};
964
965template <class _A1, class _A2>
966class __promote<_A1, _A2, void, true>
967{
968private:
969    typedef typename __promote<_A1>::type __type1;
970    typedef typename __promote<_A2>::type __type2;
971public:
972    typedef decltype(__type1() + __type2()) type;
973};
974
975template <class _A1>
976class __promote<_A1, void, void, true>
977{
978public:
979    typedef typename conditional<is_arithmetic<_A1>::value,
980                     typename conditional<is_integral<_A1>::value, double, _A1>::type,
981                     void
982            >::type type;
983};
984
985#ifdef _LIBCPP_STORE_AS_OPTIMIZATION
986
987// __transform
988
989template <class _Tp, size_t = sizeof(_Tp), bool = is_scalar<_Tp>::value> struct __transform {typedef _Tp type;};
990template <class _Tp> struct __transform<_Tp, 1, true> {typedef unsigned char      type;};
991template <class _Tp> struct __transform<_Tp, 2, true> {typedef unsigned short     type;};
992template <class _Tp> struct __transform<_Tp, 4, true> {typedef unsigned int       type;};
993template <class _Tp> struct __transform<_Tp, 8, true> {typedef unsigned long long type;};
994
995#endif  // _LIBCPP_STORE_AS_OPTIMIZATION
996
997// make_signed / make_unsigned
998
999typedef
1000    __type_list<signed char,
1001    __type_list<signed short,
1002    __type_list<signed int,
1003    __type_list<signed long,
1004    __type_list<signed long long,
1005    __nat
1006    > > > > > __signed_types;
1007
1008typedef
1009    __type_list<unsigned char,
1010    __type_list<unsigned short,
1011    __type_list<unsigned int,
1012    __type_list<unsigned long,
1013    __type_list<unsigned long long,
1014    __nat
1015    > > > > > __unsigned_types;
1016
1017template <class _TypeList, size_t _Size, bool = _Size <= sizeof(typename _TypeList::_Head)> struct __find_first;
1018
1019template <class _Hp, class _Tp, size_t _Size>
1020struct __find_first<__type_list<_Hp, _Tp>, _Size, true>
1021{
1022    typedef _Hp type;
1023};
1024
1025template <class _Hp, class _Tp, size_t _Size>
1026struct __find_first<__type_list<_Hp, _Tp>, _Size, false>
1027{
1028    typedef typename __find_first<_Tp, _Size>::type type;
1029};
1030
1031template <class _Tp, class _Up, bool = is_const<typename remove_reference<_Tp>::type>::value,
1032                             bool = is_volatile<typename remove_reference<_Tp>::type>::value>
1033struct __apply_cv
1034{
1035    typedef _Up type;
1036};
1037
1038template <class _Tp, class _Up>
1039struct __apply_cv<_Tp, _Up, true, false>
1040{
1041    typedef const _Up type;
1042};
1043
1044template <class _Tp, class _Up>
1045struct __apply_cv<_Tp, _Up, false, true>
1046{
1047    typedef volatile _Up type;
1048};
1049
1050template <class _Tp, class _Up>
1051struct __apply_cv<_Tp, _Up, true, true>
1052{
1053    typedef const volatile _Up type;
1054};
1055
1056template <class _Tp, class _Up>
1057struct __apply_cv<_Tp&, _Up, false, false>
1058{
1059    typedef _Up& type;
1060};
1061
1062template <class _Tp, class _Up>
1063struct __apply_cv<_Tp&, _Up, true, false>
1064{
1065    typedef const _Up& type;
1066};
1067
1068template <class _Tp, class _Up>
1069struct __apply_cv<_Tp&, _Up, false, true>
1070{
1071    typedef volatile _Up& type;
1072};
1073
1074template <class _Tp, class _Up>
1075struct __apply_cv<_Tp&, _Up, true, true>
1076{
1077    typedef const volatile _Up& type;
1078};
1079
1080template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
1081struct __make_signed {};
1082
1083template <class _Tp>
1084struct __make_signed<_Tp, true>
1085{
1086    typedef typename __find_first<__signed_types, sizeof(_Tp)>::type type;
1087};
1088
1089template <> struct __make_signed<bool,               true> {};
1090template <> struct __make_signed<  signed short,     true> {typedef short     type;};
1091template <> struct __make_signed<unsigned short,     true> {typedef short     type;};
1092template <> struct __make_signed<  signed int,       true> {typedef int       type;};
1093template <> struct __make_signed<unsigned int,       true> {typedef int       type;};
1094template <> struct __make_signed<  signed long,      true> {typedef long      type;};
1095template <> struct __make_signed<unsigned long,      true> {typedef long      type;};
1096template <> struct __make_signed<  signed long long, true> {typedef long long type;};
1097template <> struct __make_signed<unsigned long long, true> {typedef long long type;};
1098
1099template <class _Tp>
1100struct _LIBCPP_VISIBLE make_signed
1101{
1102    typedef typename __apply_cv<_Tp, typename __make_signed<typename remove_cv<_Tp>::type>::type>::type type;
1103};
1104
1105template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
1106struct __make_unsigned {};
1107
1108template <class _Tp>
1109struct __make_unsigned<_Tp, true>
1110{
1111    typedef typename __find_first<__unsigned_types, sizeof(_Tp)>::type type;
1112};
1113
1114template <> struct __make_unsigned<bool,               true> {};
1115template <> struct __make_unsigned<  signed short,     true> {typedef unsigned short     type;};
1116template <> struct __make_unsigned<unsigned short,     true> {typedef unsigned short     type;};
1117template <> struct __make_unsigned<  signed int,       true> {typedef unsigned int       type;};
1118template <> struct __make_unsigned<unsigned int,       true> {typedef unsigned int       type;};
1119template <> struct __make_unsigned<  signed long,      true> {typedef unsigned long      type;};
1120template <> struct __make_unsigned<unsigned long,      true> {typedef unsigned long      type;};
1121template <> struct __make_unsigned<  signed long long, true> {typedef unsigned long long type;};
1122template <> struct __make_unsigned<unsigned long long, true> {typedef unsigned long long type;};
1123
1124template <class _Tp>
1125struct _LIBCPP_VISIBLE make_unsigned
1126{
1127    typedef typename __apply_cv<_Tp, typename __make_unsigned<typename remove_cv<_Tp>::type>::type>::type type;
1128};
1129
1130#ifdef _LIBCPP_HAS_NO_VARIADICS
1131
1132template <class _Tp, class _Up = void, class V = void>
1133struct _LIBCPP_VISIBLE common_type
1134{
1135public:
1136    typedef typename common_type<typename common_type<_Tp, _Up>::type, V>::type type;
1137};
1138
1139template <class _Tp>
1140struct _LIBCPP_VISIBLE common_type<_Tp, void, void>
1141{
1142public:
1143    typedef _Tp type;
1144};
1145
1146template <class _Tp, class _Up>
1147struct _LIBCPP_VISIBLE common_type<_Tp, _Up, void>
1148{
1149private:
1150#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1151    static _Tp&& __t();
1152    static _Up&& __u();
1153#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1154    static _Tp __t();
1155    static _Up __u();
1156#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1157public:
1158    typedef typename remove_reference<decltype(true ? __t() : __u())>::type type;
1159};
1160
1161#else  // _LIBCPP_HAS_NO_VARIADICS
1162
1163template <class ..._Tp> struct common_type;
1164
1165template <class _Tp>
1166struct _LIBCPP_VISIBLE common_type<_Tp>
1167{
1168    typedef _Tp type;
1169};
1170
1171template <class _Tp, class _Up>
1172struct _LIBCPP_VISIBLE common_type<_Tp, _Up>
1173{
1174private:
1175    static _Tp&& __t();
1176    static _Up&& __u();
1177    static bool __f();
1178public:
1179    typedef typename remove_reference<decltype(__f() ? __t() : __u())>::type type;
1180};
1181
1182template <class _Tp, class _Up, class ..._Vp>
1183struct _LIBCPP_VISIBLE common_type<_Tp, _Up, _Vp...>
1184{
1185    typedef typename common_type<typename common_type<_Tp, _Up>::type, _Vp...>::type type;
1186};
1187
1188#endif  // _LIBCPP_HAS_NO_VARIADICS
1189
1190// is_assignable
1191
1192template <class _Tp, class _Arg>
1193decltype((_VSTD::declval<_Tp>() = _VSTD::declval<_Arg>(), true_type()))
1194#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1195__is_assignable_test(_Tp&&, _Arg&&);
1196#else
1197__is_assignable_test(_Tp, _Arg&);
1198#endif
1199
1200template <class _Arg>
1201false_type
1202#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1203__is_assignable_test(__any, _Arg&&);
1204#else
1205__is_assignable_test(__any, _Arg&);
1206#endif
1207
1208template <class _Tp, class _Arg, bool = is_void<_Tp>::value || is_void<_Arg>::value>
1209struct __is_assignable_imp
1210    : public common_type
1211        <
1212            decltype(__is_assignable_test(declval<_Tp>(), declval<_Arg>()))
1213        >::type {};
1214
1215template <class _Tp, class _Arg>
1216struct __is_assignable_imp<_Tp, _Arg, true>
1217    : public false_type
1218{
1219};
1220
1221template <class _Tp, class _Arg>
1222struct is_assignable
1223    : public __is_assignable_imp<_Tp, _Arg> {};
1224
1225// is_copy_assignable
1226
1227template <class _Tp> struct _LIBCPP_VISIBLE is_copy_assignable
1228    : public is_assignable<typename add_lvalue_reference<_Tp>::type,
1229                     const typename add_lvalue_reference<_Tp>::type> {};
1230
1231// is_move_assignable
1232
1233template <class _Tp> struct _LIBCPP_VISIBLE is_move_assignable
1234#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1235    : public is_assignable<typename add_lvalue_reference<_Tp>::type,
1236                     const typename add_rvalue_reference<_Tp>::type> {};
1237#else
1238    : public is_copy_assignable<_Tp> {};
1239#endif
1240
1241// is_destructible
1242
1243template <class _Tp>
1244struct __destructible_test
1245{
1246    _Tp __t;
1247};
1248
1249template <class _Tp>
1250decltype((_VSTD::declval<__destructible_test<_Tp> >().~__destructible_test<_Tp>(), true_type()))
1251#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1252__is_destructible_test(_Tp&&);
1253#else
1254__is_destructible_test(_Tp&);
1255#endif
1256
1257false_type
1258__is_destructible_test(__any);
1259
1260template <class _Tp, bool = is_void<_Tp>::value || is_abstract<_Tp>::value>
1261struct __destructible_imp
1262    : public common_type
1263        <
1264            decltype(__is_destructible_test(declval<_Tp>()))
1265        >::type {};
1266
1267template <class _Tp>
1268struct __destructible_imp<_Tp, true>
1269    : public false_type {};
1270
1271template <class _Tp>
1272struct is_destructible
1273    : public __destructible_imp<_Tp> {};
1274
1275// move
1276
1277#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1278
1279template <class _Tp>
1280inline _LIBCPP_INLINE_VISIBILITY
1281typename remove_reference<_Tp>::type&&
1282move(_Tp&& __t) _NOEXCEPT
1283{
1284    typedef typename remove_reference<_Tp>::type _Up;
1285    return static_cast<_Up&&>(__t);
1286}
1287
1288template <class _Tp>
1289inline _LIBCPP_INLINE_VISIBILITY
1290_Tp&&
1291forward(typename std::remove_reference<_Tp>::type& __t) _NOEXCEPT
1292{
1293    return static_cast<_Tp&&>(__t);
1294}
1295
1296template <class _Tp>
1297inline _LIBCPP_INLINE_VISIBILITY
1298_Tp&&
1299forward(typename std::remove_reference<_Tp>::type&& __t) _NOEXCEPT
1300{
1301    static_assert(!std::is_lvalue_reference<_Tp>::value,
1302                  "Can not forward an rvalue as an lvalue.");
1303    return static_cast<_Tp&&>(__t);
1304}
1305
1306#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1307
1308template <class _Tp>
1309inline _LIBCPP_INLINE_VISIBILITY
1310_Tp&
1311move(_Tp& __t)
1312{
1313    return __t;
1314}
1315
1316template <class _Tp>
1317inline _LIBCPP_INLINE_VISIBILITY
1318const _Tp&
1319move(const _Tp& __t)
1320{
1321    return __t;
1322}
1323
1324template <class _Tp>
1325inline _LIBCPP_INLINE_VISIBILITY
1326_Tp&
1327forward(typename std::remove_reference<_Tp>::type& __t) _NOEXCEPT
1328{
1329    return __t;
1330}
1331
1332
1333template <class _Tp>
1334class __rv
1335{
1336    typedef typename remove_reference<_Tp>::type _Trr;
1337    _Trr& t_;
1338public:
1339    _LIBCPP_INLINE_VISIBILITY
1340    _Trr* operator->() {return &t_;}
1341    _LIBCPP_INLINE_VISIBILITY
1342    explicit __rv(_Trr& __t) : t_(__t) {}
1343};
1344
1345#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1346
1347template <class _Tp>
1348struct _LIBCPP_VISIBLE decay
1349{
1350private:
1351    typedef typename remove_reference<_Tp>::type _Up;
1352public:
1353    typedef typename conditional
1354                     <
1355                         is_array<_Up>::value,
1356                         typename remove_extent<_Up>::type*,
1357                         typename conditional
1358                         <
1359                              is_function<_Up>::value,
1360                              typename add_pointer<_Up>::type,
1361                              typename remove_cv<_Up>::type
1362                         >::type
1363                     >::type type;
1364};
1365
1366#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1367
1368template <class _Tp>
1369inline _LIBCPP_INLINE_VISIBILITY
1370typename decay<_Tp>::type
1371__decay_copy(_Tp&& __t)
1372{
1373    return _VSTD::forward<_Tp>(__t);
1374}
1375
1376#else
1377
1378template <class _Tp>
1379inline _LIBCPP_INLINE_VISIBILITY
1380typename decay<_Tp>::type
1381__decay_copy(const _Tp& __t)
1382{
1383    return _VSTD::forward<_Tp>(__t);
1384}
1385
1386#endif
1387
1388template <class _MP, bool _IsMemberFuctionPtr, bool _IsMemberObjectPtr>
1389struct __member_pointer_traits_imp
1390{
1391};
1392
1393#ifndef _LIBCPP_HAS_NO_VARIADICS
1394
1395template <class _Rp, class _Class, class ..._Param>
1396struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...), true, false>
1397{
1398    typedef _Class _ClassType;
1399    typedef _Rp _ReturnType;
1400};
1401
1402template <class _Rp, class _Class, class ..._Param>
1403struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const, true, false>
1404{
1405    typedef _Class const _ClassType;
1406    typedef _Rp _ReturnType;
1407};
1408
1409template <class _Rp, class _Class, class ..._Param>
1410struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile, true, false>
1411{
1412    typedef _Class volatile _ClassType;
1413    typedef _Rp _ReturnType;
1414};
1415
1416template <class _Rp, class _Class, class ..._Param>
1417struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile, true, false>
1418{
1419    typedef _Class const volatile _ClassType;
1420    typedef _Rp _ReturnType;
1421};
1422
1423#if __has_feature(cxx_reference_qualified_functions)
1424
1425template <class _Rp, class _Class, class ..._Param>
1426struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) &, true, false>
1427{
1428    typedef _Class& _ClassType;
1429    typedef _Rp _ReturnType;
1430};
1431
1432template <class _Rp, class _Class, class ..._Param>
1433struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const&, true, false>
1434{
1435    typedef _Class const& _ClassType;
1436    typedef _Rp _ReturnType;
1437};
1438
1439template <class _Rp, class _Class, class ..._Param>
1440struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile&, true, false>
1441{
1442    typedef _Class volatile& _ClassType;
1443    typedef _Rp _ReturnType;
1444};
1445
1446template <class _Rp, class _Class, class ..._Param>
1447struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile&, true, false>
1448{
1449    typedef _Class const volatile& _ClassType;
1450    typedef _Rp _ReturnType;
1451};
1452
1453template <class _Rp, class _Class, class ..._Param>
1454struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) &&, true, false>
1455{
1456    typedef _Class&& _ClassType;
1457    typedef _Rp _ReturnType;
1458};
1459
1460template <class _Rp, class _Class, class ..._Param>
1461struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const&&, true, false>
1462{
1463    typedef _Class const&& _ClassType;
1464    typedef _Rp _ReturnType;
1465};
1466
1467template <class _Rp, class _Class, class ..._Param>
1468struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) volatile&&, true, false>
1469{
1470    typedef _Class volatile&& _ClassType;
1471    typedef _Rp _ReturnType;
1472};
1473
1474template <class _Rp, class _Class, class ..._Param>
1475struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) const volatile&&, true, false>
1476{
1477    typedef _Class const volatile&& _ClassType;
1478    typedef _Rp _ReturnType;
1479};
1480
1481#endif  // __has_feature(cxx_reference_qualified_functions)
1482
1483#else  // _LIBCPP_HAS_NO_VARIADICS
1484
1485template <class _Rp, class _Class>
1486struct __member_pointer_traits_imp<_Rp (_Class::*)(), true, false>
1487{
1488    typedef _Class _ClassType;
1489    typedef _Rp _ReturnType;
1490};
1491
1492template <class _Rp, class _Class, class _P0>
1493struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0), true, false>
1494{
1495    typedef _Class _ClassType;
1496    typedef _Rp _ReturnType;
1497};
1498
1499template <class _Rp, class _Class, class _P0, class _P1>
1500struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1), true, false>
1501{
1502    typedef _Class _ClassType;
1503    typedef _Rp _ReturnType;
1504};
1505
1506template <class _Rp, class _Class, class _P0, class _P1, class _P2>
1507struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2), true, false>
1508{
1509    typedef _Class _ClassType;
1510    typedef _Rp _ReturnType;
1511};
1512
1513template <class _Rp, class _Class>
1514struct __member_pointer_traits_imp<_Rp (_Class::*)() const, true, false>
1515{
1516    typedef _Class const _ClassType;
1517    typedef _Rp _ReturnType;
1518};
1519
1520template <class _Rp, class _Class, class _P0>
1521struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) const, true, false>
1522{
1523    typedef _Class const _ClassType;
1524    typedef _Rp _ReturnType;
1525};
1526
1527template <class _Rp, class _Class, class _P0, class _P1>
1528struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) const, true, false>
1529{
1530    typedef _Class const _ClassType;
1531    typedef _Rp _ReturnType;
1532};
1533
1534template <class _Rp, class _Class, class _P0, class _P1, class _P2>
1535struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) const, true, false>
1536{
1537    typedef _Class const _ClassType;
1538    typedef _Rp _ReturnType;
1539};
1540
1541template <class _Rp, class _Class>
1542struct __member_pointer_traits_imp<_Rp (_Class::*)() volatile, true, false>
1543{
1544    typedef _Class volatile _ClassType;
1545    typedef _Rp _ReturnType;
1546};
1547
1548template <class _Rp, class _Class, class _P0>
1549struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) volatile, true, false>
1550{
1551    typedef _Class volatile _ClassType;
1552    typedef _Rp _ReturnType;
1553};
1554
1555template <class _Rp, class _Class, class _P0, class _P1>
1556struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) volatile, true, false>
1557{
1558    typedef _Class volatile _ClassType;
1559    typedef _Rp _ReturnType;
1560};
1561
1562template <class _Rp, class _Class, class _P0, class _P1, class _P2>
1563struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) volatile, true, false>
1564{
1565    typedef _Class volatile _ClassType;
1566    typedef _Rp _ReturnType;
1567};
1568
1569template <class _Rp, class _Class>
1570struct __member_pointer_traits_imp<_Rp (_Class::*)() const volatile, true, false>
1571{
1572    typedef _Class const volatile _ClassType;
1573    typedef _Rp _ReturnType;
1574};
1575
1576template <class _Rp, class _Class, class _P0>
1577struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0) const volatile, true, false>
1578{
1579    typedef _Class const volatile _ClassType;
1580    typedef _Rp _ReturnType;
1581};
1582
1583template <class _Rp, class _Class, class _P0, class _P1>
1584struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1) const volatile, true, false>
1585{
1586    typedef _Class const volatile _ClassType;
1587    typedef _Rp _ReturnType;
1588};
1589
1590template <class _Rp, class _Class, class _P0, class _P1, class _P2>
1591struct __member_pointer_traits_imp<_Rp (_Class::*)(_P0, _P1, _P2) const volatile, true, false>
1592{
1593    typedef _Class const volatile _ClassType;
1594    typedef _Rp _ReturnType;
1595};
1596
1597#endif  // _LIBCPP_HAS_NO_VARIADICS
1598
1599template <class _Rp, class _Class>
1600struct __member_pointer_traits_imp<_Rp _Class::*, false, true>
1601{
1602    typedef _Class _ClassType;
1603    typedef _Rp _ReturnType;
1604};
1605
1606template <class _MP>
1607struct __member_pointer_traits
1608    : public __member_pointer_traits_imp<_MP,
1609                    is_member_function_pointer<_MP>::value,
1610                    is_member_object_pointer<_MP>::value>
1611{
1612//     typedef ... _ClassType;
1613//     typedef ... _ReturnType;
1614};
1615
1616// result_of
1617
1618template <class _Callable> class result_of;
1619
1620#ifdef _LIBCPP_HAS_NO_VARIADICS
1621
1622template <class _Fn, bool, bool>
1623class __result_of
1624{
1625};
1626
1627template <class _Fn>
1628class __result_of<_Fn(), true, false>
1629{
1630public:
1631    typedef decltype(declval<_Fn>()()) type;
1632};
1633
1634template <class _Fn, class _A0>
1635class __result_of<_Fn(_A0), true, false>
1636{
1637public:
1638    typedef decltype(declval<_Fn>()(declval<_A0>())) type;
1639};
1640
1641template <class _Fn, class _A0, class _A1>
1642class __result_of<_Fn(_A0, _A1), true, false>
1643{
1644public:
1645    typedef decltype(declval<_Fn>()(declval<_A0>(), declval<_A1>())) type;
1646};
1647
1648template <class _Fn, class _A0, class _A1, class _A2>
1649class __result_of<_Fn(_A0, _A1, _A2), true, false>
1650{
1651public:
1652    typedef decltype(declval<_Fn>()(declval<_A0>(), declval<_A1>(), declval<_A2>())) type;
1653};
1654
1655template <class _MP, class _Tp, bool _IsMemberFunctionPtr>
1656struct __result_of_mp;
1657
1658// member function pointer
1659
1660template <class _MP, class _Tp>
1661struct __result_of_mp<_MP, _Tp, true>
1662    : public common_type<typename __member_pointer_traits<_MP>::_ReturnType>
1663{
1664};
1665
1666// member data pointer
1667
1668template <class _MP, class _Tp, bool>
1669struct __result_of_mdp;
1670
1671template <class _Rp, class _Class, class _Tp>
1672struct __result_of_mdp<_Rp _Class::*, _Tp, false>
1673{
1674    typedef typename __apply_cv<decltype(*_VSTD::declval<_Tp>()), _Rp>::type& type;
1675};
1676
1677template <class _Rp, class _Class, class _Tp>
1678struct __result_of_mdp<_Rp _Class::*, _Tp, true>
1679{
1680    typedef typename __apply_cv<_Tp, _Rp>::type& type;
1681};
1682
1683template <class _Rp, class _Class, class _Tp>
1684struct __result_of_mp<_Rp _Class::*, _Tp, false>
1685    : public __result_of_mdp<_Rp _Class::*, _Tp,
1686            is_base_of<_Class, typename remove_reference<_Tp>::type>::value>
1687{
1688};
1689
1690
1691
1692template <class _Fn, class _Tp>
1693class __result_of<_Fn(_Tp), false, true>  // _Fn must be member pointer
1694    : public __result_of_mp<typename remove_reference<_Fn>::type,
1695                            _Tp,
1696                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
1697{
1698};
1699
1700template <class _Fn, class _Tp, class _A0>
1701class __result_of<_Fn(_Tp, _A0), false, true>  // _Fn must be member pointer
1702    : public __result_of_mp<typename remove_reference<_Fn>::type,
1703                            _Tp,
1704                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
1705{
1706};
1707
1708template <class _Fn, class _Tp, class _A0, class _A1>
1709class __result_of<_Fn(_Tp, _A0, _A1), false, true>  // _Fn must be member pointer
1710    : public __result_of_mp<typename remove_reference<_Fn>::type,
1711                            _Tp,
1712                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
1713{
1714};
1715
1716template <class _Fn, class _Tp, class _A0, class _A1, class _A2>
1717class __result_of<_Fn(_Tp, _A0, _A1, _A2), false, true>  // _Fn must be member pointer
1718    : public __result_of_mp<typename remove_reference<_Fn>::type,
1719                            _Tp,
1720                            is_member_function_pointer<typename remove_reference<_Fn>::type>::value>
1721{
1722};
1723
1724// result_of
1725
1726template <class _Fn>
1727class _LIBCPP_VISIBLE result_of<_Fn()>
1728    : public __result_of<_Fn(),
1729                         is_class<typename remove_reference<_Fn>::type>::value ||
1730                         is_function<typename remove_reference<_Fn>::type>::value,
1731                         is_member_pointer<typename remove_reference<_Fn>::type>::value
1732                        >
1733{
1734};
1735
1736template <class _Fn, class _A0>
1737class _LIBCPP_VISIBLE result_of<_Fn(_A0)>
1738    : public __result_of<_Fn(_A0),
1739                         is_class<typename remove_reference<_Fn>::type>::value ||
1740                         is_function<typename remove_reference<_Fn>::type>::value,
1741                         is_member_pointer<typename remove_reference<_Fn>::type>::value
1742                        >
1743{
1744};
1745
1746template <class _Fn, class _A0, class _A1>
1747class _LIBCPP_VISIBLE result_of<_Fn(_A0, _A1)>
1748    : public __result_of<_Fn(_A0, _A1),
1749                         is_class<typename remove_reference<_Fn>::type>::value ||
1750                         is_function<typename remove_reference<_Fn>::type>::value,
1751                         is_member_pointer<typename remove_reference<_Fn>::type>::value
1752                        >
1753{
1754};
1755
1756template <class _Fn, class _A0, class _A1, class _A2>
1757class _LIBCPP_VISIBLE result_of<_Fn(_A0, _A1, _A2)>
1758    : public __result_of<_Fn(_A0, _A1, _A2),
1759                         is_class<typename remove_reference<_Fn>::type>::value ||
1760                         is_function<typename remove_reference<_Fn>::type>::value,
1761                         is_member_pointer<typename remove_reference<_Fn>::type>::value
1762                        >
1763{
1764};
1765
1766#endif  // _LIBCPP_HAS_NO_VARIADICS
1767
1768#ifndef _LIBCPP_HAS_NO_VARIADICS
1769
1770// template <class T, class... Args> struct is_constructible;
1771
1772//      main is_constructible test
1773
1774template <class _Tp, class ..._Args>
1775decltype(_VSTD::move(_Tp(_VSTD::declval<_Args>()...)), true_type())
1776__is_constructible_test(_Tp&&, _Args&& ...);
1777
1778template <class ..._Args>
1779false_type
1780__is_constructible_test(__any, _Args&& ...);
1781
1782template <bool, class _Tp, class... _Args>
1783struct __is_constructible // false, _Tp is not a scalar
1784    : public common_type
1785             <
1786                 decltype(__is_constructible_test(declval<_Tp>(), declval<_Args>()...))
1787             >::type
1788    {};
1789
1790//      function types are not constructible
1791
1792template <class _Rp, class... _A1, class... _A2>
1793struct __is_constructible<false, _Rp(_A1...), _A2...>
1794    : public false_type
1795    {};
1796
1797//      handle scalars and reference types
1798
1799//      Scalars are default constructible, references are not
1800
1801template <class _Tp>
1802struct __is_constructible<true, _Tp>
1803    : public is_scalar<_Tp>
1804    {};
1805
1806//      Scalars and references are constructible from one arg if that arg is
1807//          implicitly convertible to the scalar or reference.
1808
1809template <class _Tp>
1810struct __is_constructible_ref
1811{
1812    true_type static __(_Tp);
1813    false_type static __(...);
1814};
1815
1816template <class _Tp, class _A0>
1817struct __is_constructible<true, _Tp, _A0>
1818    : public common_type
1819             <
1820                 decltype(__is_constructible_ref<_Tp>::__(declval<_A0>()))
1821             >::type
1822    {};
1823
1824//      Scalars and references are not constructible from multiple args.
1825
1826template <class _Tp, class _A0, class ..._Args>
1827struct __is_constructible<true, _Tp, _A0, _Args...>
1828    : public false_type
1829    {};
1830
1831//      Treat scalars and reference types separately
1832
1833template <bool, class _Tp, class... _Args>
1834struct __is_constructible_void_check
1835    : public __is_constructible<is_scalar<_Tp>::value || is_reference<_Tp>::value,
1836                                _Tp, _Args...>
1837    {};
1838
1839//      If any of T or Args is void, is_constructible should be false
1840
1841template <class _Tp, class... _Args>
1842struct __is_constructible_void_check<true, _Tp, _Args...>
1843    : public false_type
1844    {};
1845
1846template <class ..._Args> struct __contains_void;
1847
1848template <> struct __contains_void<> : false_type {};
1849
1850template <class _A0, class ..._Args>
1851struct __contains_void<_A0, _Args...>
1852{
1853    static const bool value = is_void<_A0>::value ||
1854                              __contains_void<_Args...>::value;
1855};
1856
1857//      is_constructible entry point
1858
1859template <class _Tp, class... _Args>
1860struct _LIBCPP_VISIBLE is_constructible
1861    : public __is_constructible_void_check<__contains_void<_Tp, _Args...>::value
1862                                        || is_abstract<_Tp>::value,
1863                                           _Tp, _Args...>
1864    {};
1865
1866//      Array types are default constructible if their element type
1867//      is default constructible
1868
1869template <class _Ap, size_t _Np>
1870struct __is_constructible<false, _Ap[_Np]>
1871    : public is_constructible<typename remove_all_extents<_Ap>::type>
1872    {};
1873
1874//      Otherwise array types are not constructible by this syntax
1875
1876template <class _Ap, size_t _Np, class ..._Args>
1877struct __is_constructible<false, _Ap[_Np], _Args...>
1878    : public false_type
1879    {};
1880
1881//      Incomplete array types are not constructible
1882
1883template <class _Ap, class ..._Args>
1884struct __is_constructible<false, _Ap[], _Args...>
1885    : public false_type
1886    {};
1887
1888#else  // _LIBCPP_HAS_NO_VARIADICS
1889
1890// template <class T> struct is_constructible0;
1891
1892//      main is_constructible0 test
1893
1894template <class _Tp>
1895decltype((_Tp(), true_type()))
1896__is_constructible0_test(_Tp&);
1897
1898false_type
1899__is_constructible0_test(__any);
1900
1901template <class _Tp, class _A0>
1902decltype((_Tp(_VSTD::declval<_A0>()), true_type()))
1903__is_constructible1_test(_Tp&, _A0&);
1904
1905template <class _A0>
1906false_type
1907__is_constructible1_test(__any, _A0&);
1908
1909template <class _Tp, class _A0, class _A1>
1910decltype((_Tp(_VSTD::declval<_A0>(), _VSTD::declval<_A1>()), true_type()))
1911__is_constructible2_test(_Tp&, _A0&, _A1&);
1912
1913template <class _A0, class _A1>
1914false_type
1915__is_constructible2_test(__any, _A0&, _A1&);
1916
1917template <bool, class _Tp>
1918struct __is_constructible0_imp // false, _Tp is not a scalar
1919    : public common_type
1920             <
1921                 decltype(__is_constructible0_test(declval<_Tp&>()))
1922             >::type
1923    {};
1924
1925template <bool, class _Tp, class _A0>
1926struct __is_constructible1_imp // false, _Tp is not a scalar
1927    : public common_type
1928             <
1929                 decltype(__is_constructible1_test(declval<_Tp&>(), declval<_A0&>()))
1930             >::type
1931    {};
1932
1933template <bool, class _Tp, class _A0, class _A1>
1934struct __is_constructible2_imp // false, _Tp is not a scalar
1935    : public common_type
1936             <
1937                 decltype(__is_constructible2_test(declval<_Tp&>(), declval<_A0>(), declval<_A1>()))
1938             >::type
1939    {};
1940
1941//      handle scalars and reference types
1942
1943//      Scalars are default constructible, references are not
1944
1945template <class _Tp>
1946struct __is_constructible0_imp<true, _Tp>
1947    : public is_scalar<_Tp>
1948    {};
1949
1950template <class _Tp, class _A0>
1951struct __is_constructible1_imp<true, _Tp, _A0>
1952    : public is_convertible<_A0, _Tp>
1953    {};
1954
1955template <class _Tp, class _A0, class _A1>
1956struct __is_constructible2_imp<true, _Tp, _A0, _A1>
1957    : public false_type
1958    {};
1959
1960//      Treat scalars and reference types separately
1961
1962template <bool, class _Tp>
1963struct __is_constructible0_void_check
1964    : public __is_constructible0_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
1965                                _Tp>
1966    {};
1967
1968template <bool, class _Tp, class _A0>
1969struct __is_constructible1_void_check
1970    : public __is_constructible1_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
1971                                _Tp, _A0>
1972    {};
1973
1974template <bool, class _Tp, class _A0, class _A1>
1975struct __is_constructible2_void_check
1976    : public __is_constructible2_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value,
1977                                _Tp, _A0, _A1>
1978    {};
1979
1980//      If any of T or Args is void, is_constructible should be false
1981
1982template <class _Tp>
1983struct __is_constructible0_void_check<true, _Tp>
1984    : public false_type
1985    {};
1986
1987template <class _Tp, class _A0>
1988struct __is_constructible1_void_check<true, _Tp, _A0>
1989    : public false_type
1990    {};
1991
1992template <class _Tp, class _A0, class _A1>
1993struct __is_constructible2_void_check<true, _Tp, _A0, _A1>
1994    : public false_type
1995    {};
1996
1997//      is_constructible entry point
1998
1999namespace __is_construct
2000{
2001
2002struct __nat {};
2003
2004}
2005
2006template <class _Tp, class _A0 = __is_construct::__nat,
2007                     class _A1 = __is_construct::__nat>
2008struct _LIBCPP_VISIBLE is_constructible
2009    : public __is_constructible2_void_check<is_void<_Tp>::value
2010                                        || is_abstract<_Tp>::value
2011                                        || is_function<_Tp>::value
2012                                        || is_void<_A0>::value
2013                                        || is_void<_A1>::value,
2014                                           _Tp, _A0, _A1>
2015    {};
2016
2017template <class _Tp>
2018struct _LIBCPP_VISIBLE is_constructible<_Tp, __is_construct::__nat, __is_construct::__nat>
2019    : public __is_constructible0_void_check<is_void<_Tp>::value
2020                                        || is_abstract<_Tp>::value
2021                                        || is_function<_Tp>::value,
2022                                           _Tp>
2023    {};
2024
2025template <class _Tp, class _A0>
2026struct _LIBCPP_VISIBLE is_constructible<_Tp, _A0, __is_construct::__nat>
2027    : public __is_constructible1_void_check<is_void<_Tp>::value
2028                                        || is_abstract<_Tp>::value
2029                                        || is_function<_Tp>::value
2030                                        || is_void<_A0>::value,
2031                                           _Tp, _A0>
2032    {};
2033
2034//      Array types are default constructible if their element type
2035//      is default constructible
2036
2037template <class _Ap, size_t _Np>
2038struct __is_constructible0_imp<false, _Ap[_Np]>
2039    : public is_constructible<typename remove_all_extents<_Ap>::type>
2040    {};
2041
2042template <class _Ap, size_t _Np, class _A0>
2043struct __is_constructible1_imp<false, _Ap[_Np], _A0>
2044    : public false_type
2045    {};
2046
2047template <class _Ap, size_t _Np, class _A0, class _A1>
2048struct __is_constructible2_imp<false, _Ap[_Np], _A0, _A1>
2049    : public false_type
2050    {};
2051
2052//      Incomplete array types are not constructible
2053
2054template <class _Ap>
2055struct __is_constructible0_imp<false, _Ap[]>
2056    : public false_type
2057    {};
2058
2059template <class _Ap, class _A0>
2060struct __is_constructible1_imp<false, _Ap[], _A0>
2061    : public false_type
2062    {};
2063
2064template <class _Ap, class _A0, class _A1>
2065struct __is_constructible2_imp<false, _Ap[], _A0, _A1>
2066    : public false_type
2067    {};
2068
2069#endif  // _LIBCPP_HAS_NO_VARIADICS
2070
2071// is_default_constructible
2072
2073template <class _Tp>
2074struct _LIBCPP_VISIBLE is_default_constructible
2075    : public is_constructible<_Tp>
2076    {};
2077
2078// is_copy_constructible
2079
2080template <class _Tp>
2081struct _LIBCPP_VISIBLE is_copy_constructible
2082    : public is_constructible<_Tp, const typename add_lvalue_reference<_Tp>::type>
2083    {};
2084
2085// is_move_constructible
2086
2087template <class _Tp>
2088struct _LIBCPP_VISIBLE is_move_constructible
2089#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2090    : public is_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
2091#else
2092    : public is_copy_constructible<_Tp>
2093#endif
2094    {};
2095
2096// is_trivially_constructible
2097
2098#ifndef _LIBCPP_HAS_NO_VARIADICS
2099
2100#if __has_feature(is_trivially_constructible)
2101
2102template <class _Tp, class... _Args>
2103struct _LIBCPP_VISIBLE is_trivially_constructible
2104    : integral_constant<bool, __is_trivially_constructible(_Tp, _Args...)>
2105{
2106};
2107
2108#else  // !__has_feature(is_trivially_constructible)
2109
2110template <class _Tp, class... _Args>
2111struct _LIBCPP_VISIBLE is_trivially_constructible
2112    : false_type
2113{
2114};
2115
2116template <class _Tp>
2117struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp>
2118#if __has_feature(has_trivial_constructor) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2119    : integral_constant<bool, __has_trivial_constructor(_Tp)>
2120#else
2121    : integral_constant<bool, is_scalar<_Tp>::value>
2122#endif
2123{
2124};
2125
2126template <class _Tp>
2127#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2128struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp&&>
2129#else
2130struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp>
2131#endif
2132    : integral_constant<bool, is_scalar<_Tp>::value>
2133{
2134};
2135
2136template <class _Tp>
2137struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, const _Tp&>
2138    : integral_constant<bool, is_scalar<_Tp>::value>
2139{
2140};
2141
2142template <class _Tp>
2143struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp&>
2144    : integral_constant<bool, is_scalar<_Tp>::value>
2145{
2146};
2147
2148#endif  // !__has_feature(is_trivially_constructible)
2149
2150#else  // _LIBCPP_HAS_NO_VARIADICS
2151
2152template <class _Tp, class _A0 = __is_construct::__nat,
2153                     class _A1 = __is_construct::__nat>
2154struct _LIBCPP_VISIBLE is_trivially_constructible
2155    : false_type
2156{
2157};
2158
2159#if __has_feature(is_trivially_constructible)
2160
2161template <class _Tp>
2162struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, __is_construct::__nat,
2163                                                       __is_construct::__nat>
2164    : integral_constant<bool, __is_trivially_constructible(_Tp)>
2165{
2166};
2167
2168template <class _Tp>
2169struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp,
2170                                                       __is_construct::__nat>
2171    : integral_constant<bool, __is_trivially_constructible(_Tp, _Tp)>
2172{
2173};
2174
2175template <class _Tp>
2176struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, const _Tp&,
2177                                                       __is_construct::__nat>
2178    : integral_constant<bool, __is_trivially_constructible(_Tp, const _Tp&)>
2179{
2180};
2181
2182template <class _Tp>
2183struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp&,
2184                                                       __is_construct::__nat>
2185    : integral_constant<bool, __is_trivially_constructible(_Tp, _Tp&)>
2186{
2187};
2188
2189#else  // !__has_feature(is_trivially_constructible)
2190
2191template <class _Tp>
2192struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, __is_construct::__nat,
2193                                                       __is_construct::__nat>
2194    : integral_constant<bool, is_scalar<_Tp>::value>
2195{
2196};
2197
2198template <class _Tp>
2199struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp,
2200                                                       __is_construct::__nat>
2201    : integral_constant<bool, is_scalar<_Tp>::value>
2202{
2203};
2204
2205template <class _Tp>
2206struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, const _Tp&,
2207                                                       __is_construct::__nat>
2208    : integral_constant<bool, is_scalar<_Tp>::value>
2209{
2210};
2211
2212template <class _Tp>
2213struct _LIBCPP_VISIBLE is_trivially_constructible<_Tp, _Tp&,
2214                                                       __is_construct::__nat>
2215    : integral_constant<bool, is_scalar<_Tp>::value>
2216{
2217};
2218
2219#endif  // !__has_feature(is_trivially_constructible)
2220
2221#endif  // _LIBCPP_HAS_NO_VARIADICS
2222
2223// is_trivially_default_constructible
2224
2225template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_default_constructible
2226    : public is_trivially_constructible<_Tp>
2227    {};
2228
2229// is_trivially_copy_constructible
2230
2231template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_copy_constructible
2232    : public is_trivially_constructible<_Tp, const typename add_lvalue_reference<_Tp>::type>
2233    {};
2234
2235// is_trivially_move_constructible
2236
2237template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_move_constructible
2238#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2239    : public is_trivially_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
2240#else
2241    : public is_trivially_copy_constructible<_Tp>
2242#endif
2243    {};
2244
2245// is_trivially_assignable
2246
2247#if __has_feature(is_trivially_constructible)
2248
2249template <class _Tp, class _Arg>
2250struct is_trivially_assignable
2251    : integral_constant<bool, __is_trivially_assignable(_Tp, _Arg)>
2252{
2253};
2254
2255#else  // !__has_feature(is_trivially_constructible)
2256
2257template <class _Tp, class _Arg>
2258struct is_trivially_assignable
2259    : public false_type {};
2260
2261template <class _Tp>
2262struct is_trivially_assignable<_Tp&, _Tp>
2263    : integral_constant<bool, is_scalar<_Tp>::value> {};
2264
2265template <class _Tp>
2266struct is_trivially_assignable<_Tp&, _Tp&>
2267    : integral_constant<bool, is_scalar<_Tp>::value> {};
2268
2269template <class _Tp>
2270struct is_trivially_assignable<_Tp&, const _Tp&>
2271    : integral_constant<bool, is_scalar<_Tp>::value> {};
2272
2273#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2274
2275template <class _Tp>
2276struct is_trivially_assignable<_Tp&, _Tp&&>
2277    : integral_constant<bool, is_scalar<_Tp>::value> {};
2278
2279#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2280
2281#endif  // !__has_feature(is_trivially_constructible)
2282
2283// is_trivially_copy_assignable
2284
2285template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_copy_assignable
2286    : public is_trivially_assignable<typename add_lvalue_reference<_Tp>::type,
2287                               const typename add_lvalue_reference<_Tp>::type>
2288    {};
2289
2290// is_trivially_move_assignable
2291
2292template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_move_assignable
2293    : public is_trivially_assignable<typename add_lvalue_reference<_Tp>::type,
2294#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2295                                     typename add_rvalue_reference<_Tp>::type>
2296#else
2297                                     typename add_lvalue_reference<_Tp>::type>
2298#endif
2299    {};
2300
2301// is_trivially_destructible
2302
2303#if __has_feature(has_trivial_destructor) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2304
2305template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_destructible
2306    : public integral_constant<bool, __has_trivial_destructor(_Tp)> {};
2307
2308#else  // _LIBCPP_HAS_TYPE_TRAITS
2309
2310template <class _Tp> struct __libcpp_trivial_destructor
2311    : public integral_constant<bool, is_scalar<_Tp>::value ||
2312                                     is_reference<_Tp>::value> {};
2313
2314template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_destructible
2315    : public __libcpp_trivial_destructor<typename remove_all_extents<_Tp>::type> {};
2316
2317#endif  // _LIBCPP_HAS_TYPE_TRAITS
2318
2319// is_nothrow_constructible
2320
2321#ifndef _LIBCPP_HAS_NO_VARIADICS
2322
2323#if __has_feature(cxx_noexcept)
2324
2325template <bool, class _Tp, class... _Args> struct __is_nothrow_constructible;
2326
2327template <class _Tp, class... _Args>
2328struct __is_nothrow_constructible<true, _Tp, _Args...>
2329    : public integral_constant<bool, noexcept(_Tp(declval<_Args>()...))>
2330{
2331};
2332
2333template <class _Tp, class... _Args>
2334struct __is_nothrow_constructible<false, _Tp, _Args...>
2335    : public false_type
2336{
2337};
2338
2339template <class _Tp, class... _Args>
2340struct _LIBCPP_VISIBLE is_nothrow_constructible
2341    : __is_nothrow_constructible<is_constructible<_Tp, _Args...>::value, _Tp, _Args...>
2342{
2343};
2344
2345template <class _Tp, size_t _Ns>
2346struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp[_Ns]>
2347    : __is_nothrow_constructible<is_constructible<_Tp>::value, _Tp>
2348{
2349};
2350
2351#else  // __has_feature(cxx_noexcept)
2352
2353template <class _Tp, class... _Args>
2354struct _LIBCPP_VISIBLE is_nothrow_constructible
2355    : false_type
2356{
2357};
2358
2359template <class _Tp>
2360struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp>
2361#if __has_feature(has_nothrow_constructor) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2362    : integral_constant<bool, __has_nothrow_constructor(_Tp)>
2363#else
2364    : integral_constant<bool, is_scalar<_Tp>::value>
2365#endif
2366{
2367};
2368
2369template <class _Tp>
2370#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2371struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, _Tp&&>
2372#else
2373struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, _Tp>
2374#endif
2375#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2376    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2377#else
2378    : integral_constant<bool, is_scalar<_Tp>::value>
2379#endif
2380{
2381};
2382
2383template <class _Tp>
2384struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, const _Tp&>
2385#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2386    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2387#else
2388    : integral_constant<bool, is_scalar<_Tp>::value>
2389#endif
2390{
2391};
2392
2393template <class _Tp>
2394struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, _Tp&>
2395#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2396    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2397#else
2398    : integral_constant<bool, is_scalar<_Tp>::value>
2399#endif
2400{
2401};
2402
2403#endif  // __has_feature(cxx_noexcept)
2404
2405#else  // _LIBCPP_HAS_NO_VARIADICS
2406
2407template <class _Tp, class _A0 = __is_construct::__nat,
2408                     class _A1 = __is_construct::__nat>
2409struct _LIBCPP_VISIBLE is_nothrow_constructible
2410    : false_type
2411{
2412};
2413
2414template <class _Tp>
2415struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, __is_construct::__nat,
2416                                                       __is_construct::__nat>
2417#if __has_feature(has_nothrow_constructor) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2418    : integral_constant<bool, __has_nothrow_constructor(_Tp)>
2419#else
2420    : integral_constant<bool, is_scalar<_Tp>::value>
2421#endif
2422{
2423};
2424
2425template <class _Tp>
2426struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, _Tp,
2427                                                       __is_construct::__nat>
2428#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2429    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2430#else
2431    : integral_constant<bool, is_scalar<_Tp>::value>
2432#endif
2433{
2434};
2435
2436template <class _Tp>
2437struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, const _Tp&,
2438                                                       __is_construct::__nat>
2439#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2440    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2441#else
2442    : integral_constant<bool, is_scalar<_Tp>::value>
2443#endif
2444{
2445};
2446
2447template <class _Tp>
2448struct _LIBCPP_VISIBLE is_nothrow_constructible<_Tp, _Tp&,
2449                                                       __is_construct::__nat>
2450#if __has_feature(has_nothrow_copy) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2451    : integral_constant<bool, __has_nothrow_copy(_Tp)>
2452#else
2453    : integral_constant<bool, is_scalar<_Tp>::value>
2454#endif
2455{
2456};
2457
2458#endif  // _LIBCPP_HAS_NO_VARIADICS
2459
2460// is_nothrow_default_constructible
2461
2462template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_default_constructible
2463    : public is_nothrow_constructible<_Tp>
2464    {};
2465
2466// is_nothrow_copy_constructible
2467
2468template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_copy_constructible
2469    : public is_nothrow_constructible<_Tp, const typename add_lvalue_reference<_Tp>::type>
2470    {};
2471
2472// is_nothrow_move_constructible
2473
2474template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_move_constructible
2475#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2476    : public is_nothrow_constructible<_Tp, typename add_rvalue_reference<_Tp>::type>
2477#else
2478    : public is_nothrow_copy_constructible<_Tp>
2479#endif
2480    {};
2481
2482// is_nothrow_assignable
2483
2484#if __has_feature(cxx_noexcept)
2485
2486template <bool, class _Tp, class _Arg> struct __is_nothrow_assignable;
2487
2488template <class _Tp, class _Arg>
2489struct __is_nothrow_assignable<false, _Tp, _Arg>
2490    : public false_type
2491{
2492};
2493
2494template <class _Tp, class _Arg>
2495struct __is_nothrow_assignable<true, _Tp, _Arg>
2496    : public integral_constant<bool, noexcept(_VSTD::declval<_Tp>() = _VSTD::declval<_Arg>()) >
2497{
2498};
2499
2500template <class _Tp, class _Arg>
2501struct _LIBCPP_VISIBLE is_nothrow_assignable
2502    : public __is_nothrow_assignable<is_assignable<_Tp, _Arg>::value, _Tp, _Arg>
2503{
2504};
2505
2506#else  // __has_feature(cxx_noexcept)
2507
2508template <class _Tp, class _Arg>
2509struct _LIBCPP_VISIBLE is_nothrow_assignable
2510    : public false_type {};
2511
2512template <class _Tp>
2513struct _LIBCPP_VISIBLE is_nothrow_assignable<_Tp&, _Tp>
2514#if __has_feature(has_nothrow_assign) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2515    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
2516#else
2517    : integral_constant<bool, is_scalar<_Tp>::value> {};
2518#endif
2519
2520template <class _Tp>
2521struct _LIBCPP_VISIBLE is_nothrow_assignable<_Tp&, _Tp&>
2522#if __has_feature(has_nothrow_assign) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2523    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
2524#else
2525    : integral_constant<bool, is_scalar<_Tp>::value> {};
2526#endif
2527
2528template <class _Tp>
2529struct _LIBCPP_VISIBLE is_nothrow_assignable<_Tp&, const _Tp&>
2530#if __has_feature(has_nothrow_assign) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2531    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
2532#else
2533    : integral_constant<bool, is_scalar<_Tp>::value> {};
2534#endif
2535
2536#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2537
2538template <class _Tp>
2539struct is_nothrow_assignable<_Tp&, _Tp&&>
2540#if __has_feature(has_nothrow_assign) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2541    : integral_constant<bool, __has_nothrow_assign(_Tp)> {};
2542#else
2543    : integral_constant<bool, is_scalar<_Tp>::value> {};
2544#endif
2545
2546#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2547
2548#endif  // __has_feature(cxx_noexcept)
2549
2550// is_nothrow_copy_assignable
2551
2552template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_copy_assignable
2553    : public is_nothrow_assignable<typename add_lvalue_reference<_Tp>::type,
2554                               const typename add_lvalue_reference<_Tp>::type>
2555    {};
2556
2557// is_nothrow_move_assignable
2558
2559template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_move_assignable
2560    : public is_nothrow_assignable<typename add_lvalue_reference<_Tp>::type,
2561#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2562                                     typename add_rvalue_reference<_Tp>::type>
2563#else
2564                                     typename add_lvalue_reference<_Tp>::type>
2565#endif
2566    {};
2567
2568// is_nothrow_destructible
2569
2570#if __has_feature(cxx_noexcept)
2571
2572template <bool, class _Tp> struct __is_nothrow_destructible;
2573
2574template <class _Tp>
2575struct __is_nothrow_destructible<false, _Tp>
2576    : public false_type
2577{
2578};
2579
2580template <class _Tp>
2581struct __is_nothrow_destructible<true, _Tp>
2582    : public integral_constant<bool, noexcept(_VSTD::declval<_Tp>().~_Tp()) >
2583{
2584};
2585
2586template <class _Tp>
2587struct _LIBCPP_VISIBLE is_nothrow_destructible
2588    : public __is_nothrow_destructible<is_destructible<_Tp>::value, _Tp>
2589{
2590};
2591
2592template <class _Tp, size_t _Ns>
2593struct _LIBCPP_VISIBLE is_nothrow_destructible<_Tp[_Ns]>
2594    : public is_nothrow_destructible<_Tp>
2595{
2596};
2597
2598template <class _Tp>
2599struct _LIBCPP_VISIBLE is_nothrow_destructible<_Tp&>
2600    : public true_type
2601{
2602};
2603
2604#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2605
2606template <class _Tp>
2607struct _LIBCPP_VISIBLE is_nothrow_destructible<_Tp&&>
2608    : public true_type
2609{
2610};
2611
2612#endif
2613
2614#else
2615
2616template <class _Tp> struct __libcpp_nothrow_destructor
2617    : public integral_constant<bool, is_scalar<_Tp>::value ||
2618                                     is_reference<_Tp>::value> {};
2619
2620template <class _Tp> struct _LIBCPP_VISIBLE is_nothrow_destructible
2621    : public __libcpp_nothrow_destructor<typename remove_all_extents<_Tp>::type> {};
2622
2623#endif
2624
2625// is_pod
2626
2627#if __has_feature(is_pod) || (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
2628
2629template <class _Tp> struct _LIBCPP_VISIBLE is_pod
2630    : public integral_constant<bool, __is_pod(_Tp)> {};
2631
2632#else  // _LIBCPP_HAS_TYPE_TRAITS
2633
2634template <class _Tp> struct _LIBCPP_VISIBLE is_pod
2635    : public integral_constant<bool, is_trivially_default_constructible<_Tp>::value   &&
2636                                     is_trivially_copy_constructible<_Tp>::value      &&
2637                                     is_trivially_copy_assignable<_Tp>::value    &&
2638                                     is_trivially_destructible<_Tp>::value> {};
2639
2640#endif  // _LIBCPP_HAS_TYPE_TRAITS
2641
2642// is_literal_type;
2643
2644template <class _Tp> struct _LIBCPP_VISIBLE is_literal_type
2645#if __has_feature(is_literal)
2646    : public integral_constant<bool, __is_literal(_Tp)>
2647#else
2648    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value ||
2649                              is_reference<typename remove_all_extents<_Tp>::type>::value>
2650#endif
2651    {};
2652    
2653// is_standard_layout;
2654
2655template <class _Tp> struct _LIBCPP_VISIBLE is_standard_layout
2656#if __has_feature(is_standard_layout)
2657    : public integral_constant<bool, __is_standard_layout(_Tp)>
2658#else
2659    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value>
2660#endif
2661    {};
2662    
2663// is_trivially_copyable;
2664
2665template <class _Tp> struct _LIBCPP_VISIBLE is_trivially_copyable
2666#if __has_feature(is_trivially_copyable)
2667    : public integral_constant<bool, __is_trivially_copyable(_Tp)>
2668#else
2669    : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value>
2670#endif
2671    {};
2672    
2673// is_trivial;
2674
2675template <class _Tp> struct _LIBCPP_VISIBLE is_trivial
2676#if __has_feature(is_trivial)
2677    : public integral_constant<bool, __is_trivial(_Tp)>
2678#else
2679    : integral_constant<bool, is_trivially_copyable<_Tp>::value &&
2680                                 is_trivially_default_constructible<_Tp>::value>
2681#endif
2682    {};
2683
2684#ifndef _LIBCPP_HAS_NO_VARIADICS
2685
2686// Check for complete types
2687
2688template <class ..._Tp> struct __check_complete;
2689
2690template <>
2691struct __check_complete<>
2692{
2693};
2694
2695template <class _Hp, class _T0, class ..._Tp>
2696struct __check_complete<_Hp, _T0, _Tp...>
2697    : private __check_complete<_Hp>,
2698      private __check_complete<_T0, _Tp...>
2699{
2700};
2701
2702template <class _Hp>
2703struct __check_complete<_Hp, _Hp>
2704    : private __check_complete<_Hp>
2705{
2706};
2707
2708template <class _Tp>
2709struct __check_complete<_Tp>
2710{
2711    static_assert(sizeof(_Tp) > 0, "Type must be complete.");
2712};
2713
2714template <class _Tp>
2715struct __check_complete<_Tp&>
2716    : private __check_complete<_Tp>
2717{
2718};
2719
2720template <class _Tp>
2721struct __check_complete<_Tp&&>
2722    : private __check_complete<_Tp>
2723{
2724};
2725
2726template <class _Rp, class ..._Param>
2727struct __check_complete<_Rp (*)(_Param...)>
2728    : private __check_complete<_Rp>
2729{
2730};
2731
2732template <class _Rp, class ..._Param>
2733struct __check_complete<_Rp (_Param...)>
2734    : private __check_complete<_Rp>
2735{
2736};
2737
2738template <class _Rp, class _Class, class ..._Param>
2739struct __check_complete<_Rp (_Class::*)(_Param...)>
2740    : private __check_complete<_Class>
2741{
2742};
2743
2744template <class _Rp, class _Class, class ..._Param>
2745struct __check_complete<_Rp (_Class::*)(_Param...) const>
2746    : private __check_complete<_Class>
2747{
2748};
2749
2750template <class _Rp, class _Class, class ..._Param>
2751struct __check_complete<_Rp (_Class::*)(_Param...) volatile>
2752    : private __check_complete<_Class>
2753{
2754};
2755
2756template <class _Rp, class _Class, class ..._Param>
2757struct __check_complete<_Rp (_Class::*)(_Param...) const volatile>
2758    : private __check_complete<_Class>
2759{
2760};
2761
2762#if __has_feature(cxx_reference_qualified_functions)
2763
2764template <class _Rp, class _Class, class ..._Param>
2765struct __check_complete<_Rp (_Class::*)(_Param...) &>
2766    : private __check_complete<_Class>
2767{
2768};
2769
2770template <class _Rp, class _Class, class ..._Param>
2771struct __check_complete<_Rp (_Class::*)(_Param...) const&>
2772    : private __check_complete<_Class>
2773{
2774};
2775
2776template <class _Rp, class _Class, class ..._Param>
2777struct __check_complete<_Rp (_Class::*)(_Param...) volatile&>
2778    : private __check_complete<_Class>
2779{
2780};
2781
2782template <class _Rp, class _Class, class ..._Param>
2783struct __check_complete<_Rp (_Class::*)(_Param...) const volatile&>
2784    : private __check_complete<_Class>
2785{
2786};
2787
2788template <class _Rp, class _Class, class ..._Param>
2789struct __check_complete<_Rp (_Class::*)(_Param...) &&>
2790    : private __check_complete<_Class>
2791{
2792};
2793
2794template <class _Rp, class _Class, class ..._Param>
2795struct __check_complete<_Rp (_Class::*)(_Param...) const&&>
2796    : private __check_complete<_Class>
2797{
2798};
2799
2800template <class _Rp, class _Class, class ..._Param>
2801struct __check_complete<_Rp (_Class::*)(_Param...) volatile&&>
2802    : private __check_complete<_Class>
2803{
2804};
2805
2806template <class _Rp, class _Class, class ..._Param>
2807struct __check_complete<_Rp (_Class::*)(_Param...) const volatile&&>
2808    : private __check_complete<_Class>
2809{
2810};
2811
2812#endif
2813
2814template <class _Rp, class _Class>
2815struct __check_complete<_Rp _Class::*>
2816    : private __check_complete<_Class>
2817{
2818};
2819
2820// __invoke forward declarations
2821
2822// fall back - none of the bullets
2823
2824template <class ..._Args>
2825auto
2826__invoke(__any, _Args&& ...__args)
2827    -> __nat;
2828
2829// bullets 1 and 2
2830
2831template <class _Fp, class _A0, class ..._Args>
2832_LIBCPP_INLINE_VISIBILITY
2833auto
2834__invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
2835    -> decltype((_VSTD::forward<_A0>(__a0).*__f)(_VSTD::forward<_Args>(__args)...));
2836
2837template <class _Fp, class _A0, class ..._Args>
2838_LIBCPP_INLINE_VISIBILITY
2839auto
2840__invoke(_Fp&& __f, _A0&& __a0, _Args&& ...__args)
2841    -> decltype(((*_VSTD::forward<_A0>(__a0)).*__f)(_VSTD::forward<_Args>(__args)...));
2842
2843// bullets 3 and 4
2844
2845template <class _Fp, class _A0>
2846_LIBCPP_INLINE_VISIBILITY
2847auto
2848__invoke(_Fp&& __f, _A0&& __a0)
2849    -> decltype(_VSTD::forward<_A0>(__a0).*__f);
2850
2851template <class _Fp, class _A0>
2852_LIBCPP_INLINE_VISIBILITY
2853auto
2854__invoke(_Fp&& __f, _A0&& __a0)
2855    -> decltype((*_VSTD::forward<_A0>(__a0)).*__f);
2856
2857// bullet 5
2858
2859template <class _Fp, class ..._Args>
2860_LIBCPP_INLINE_VISIBILITY
2861auto
2862__invoke(_Fp&& __f, _Args&& ...__args)
2863    -> decltype(_VSTD::forward<_Fp>(__f)(_VSTD::forward<_Args>(__args)...));
2864
2865// __invokable
2866
2867template <class _Fp, class ..._Args>
2868struct __invokable_imp
2869    : private __check_complete<_Fp>
2870{
2871    typedef decltype(
2872            __invoke(_VSTD::declval<_Fp>(), _VSTD::declval<_Args>()...)
2873                    ) type;
2874    static const bool value = !is_same<type, __nat>::value;
2875};
2876
2877template <class _Fp, class ..._Args>
2878struct __invokable
2879    : public integral_constant<bool,
2880          __invokable_imp<_Fp, _Args...>::value>
2881{
2882};
2883
2884// __invoke_of
2885
2886template <bool _Invokable, class _Fp, class ..._Args>
2887struct __invoke_of_imp  // false
2888{
2889};
2890
2891template <class _Fp, class ..._Args>
2892struct __invoke_of_imp<true, _Fp, _Args...>
2893{
2894    typedef typename __invokable_imp<_Fp, _Args...>::type type;
2895};
2896
2897template <class _Fp, class ..._Args>
2898struct __invoke_of
2899    : public __invoke_of_imp<__invokable<_Fp, _Args...>::value, _Fp, _Args...>
2900{
2901};
2902
2903template <class _Fp, class ..._Args>
2904class _LIBCPP_VISIBLE result_of<_Fp(_Args...)>
2905    : public __invoke_of<_Fp, _Args...>
2906{
2907};
2908
2909#endif  // _LIBCPP_HAS_NO_VARIADICS
2910
2911template <class _Tp>
2912inline _LIBCPP_INLINE_VISIBILITY
2913#ifndef _LIBCPP_HAS_NO_ADVANCED_SFINAE
2914typename enable_if
2915<
2916    is_move_constructible<_Tp>::value &&
2917    is_move_assignable<_Tp>::value
2918>::type
2919#else
2920void
2921#endif
2922swap(_Tp& __x, _Tp& __y) _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value &&
2923                                    is_nothrow_move_assignable<_Tp>::value)
2924{
2925    _Tp __t(_VSTD::move(__x));
2926    __x = _VSTD::move(__y);
2927    __y = _VSTD::move(__t);
2928}
2929
2930template <class _ForwardIterator1, class _ForwardIterator2>
2931inline _LIBCPP_INLINE_VISIBILITY
2932void
2933iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
2934    //                                  _NOEXCEPT_(_NOEXCEPT_(swap(*__a, *__b)))
2935               _NOEXCEPT_(_NOEXCEPT_(swap(*_VSTD::declval<_ForwardIterator1>(),
2936                                          *_VSTD::declval<_ForwardIterator2>())))
2937{
2938    swap(*__a, *__b);
2939}
2940
2941// __swappable
2942
2943namespace __detail
2944{
2945
2946using _VSTD::swap;
2947__nat swap(__any, __any);
2948
2949template <class _Tp>
2950struct __swappable
2951{
2952    typedef decltype(swap(_VSTD::declval<_Tp&>(), _VSTD::declval<_Tp&>())) type;
2953    static const bool value = !is_same<type, __nat>::value;
2954};
2955
2956}  // __detail
2957
2958template <class _Tp>
2959struct __is_swappable
2960    : public integral_constant<bool, __detail::__swappable<_Tp>::value>
2961{
2962};
2963
2964#if __has_feature(cxx_noexcept)
2965
2966template <bool, class _Tp>
2967struct __is_nothrow_swappable_imp
2968    : public integral_constant<bool, noexcept(swap(_VSTD::declval<_Tp&>(),
2969                                                   _VSTD::declval<_Tp&>()))>
2970{
2971};
2972
2973template <class _Tp>
2974struct __is_nothrow_swappable_imp<false, _Tp>
2975    : public false_type
2976{
2977};
2978
2979template <class _Tp>
2980struct __is_nothrow_swappable
2981    : public __is_nothrow_swappable_imp<__is_swappable<_Tp>::value, _Tp>
2982{
2983};
2984
2985#else  // __has_feature(cxx_noexcept)
2986
2987template <class _Tp>
2988struct __is_nothrow_swappable
2989    : public false_type
2990{
2991};
2992
2993#endif  // __has_feature(cxx_noexcept)
2994
2995#ifdef _LIBCXX_UNDERLYING_TYPE
2996
2997template <class _Tp>
2998struct underlying_type
2999{
3000    typedef _LIBCXX_UNDERLYING_TYPE(_Tp) type;
3001};
3002
3003#else  // _LIBCXX_UNDERLYING_TYPE
3004
3005template <class _Tp, bool _Support = false>
3006struct underlying_type
3007{
3008    static_assert(_Support, "The underyling_type trait requires compiler "
3009                            "support. Either no such support exists or "
3010                            "libc++ does not know how to use it.");
3011};
3012
3013#endif // _LIBCXX_UNDERLYING_TYPE
3014
3015_LIBCPP_END_NAMESPACE_STD
3016
3017#endif  // _LIBCPP_TYPE_TRAITS
3018