libstdc++
type_traits
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1 // C++11 <type_traits> -*- C++ -*-
2 
3 // Copyright (C) 2007-2018 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/type_traits
26  * This is a Standard C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_TYPE_TRAITS
30 #define _GLIBCXX_TYPE_TRAITS 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <bits/c++config.h>
39 
40 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
41 # if defined (__UINT_LEAST16_TYPE__) && defined(__UINT_LEAST32_TYPE__)
42 namespace std
43 {
44  typedef __UINT_LEAST16_TYPE__ uint_least16_t;
45  typedef __UINT_LEAST32_TYPE__ uint_least32_t;
46 }
47 # else
48 # include <cstdint>
49 # endif
50 #endif
51 
52 namespace std _GLIBCXX_VISIBILITY(default)
53 {
54 _GLIBCXX_BEGIN_NAMESPACE_VERSION
55 
56  /**
57  * @defgroup metaprogramming Metaprogramming
58  * @ingroup utilities
59  *
60  * Template utilities for compile-time introspection and modification,
61  * including type classification traits, type property inspection traits
62  * and type transformation traits.
63  *
64  * @{
65  */
66 
67  /// integral_constant
68  template<typename _Tp, _Tp __v>
69  struct integral_constant
70  {
71  static constexpr _Tp value = __v;
72  typedef _Tp value_type;
73  typedef integral_constant<_Tp, __v> type;
74  constexpr operator value_type() const noexcept { return value; }
75 #if __cplusplus > 201103L
76 
77 #define __cpp_lib_integral_constant_callable 201304
78 
79  constexpr value_type operator()() const noexcept { return value; }
80 #endif
81  };
82 
83  template<typename _Tp, _Tp __v>
84  constexpr _Tp integral_constant<_Tp, __v>::value;
85 
86  /// The type used as a compile-time boolean with true value.
87  typedef integral_constant<bool, true> true_type;
88 
89  /// The type used as a compile-time boolean with false value.
90  typedef integral_constant<bool, false> false_type;
91 
92  template<bool __v>
93  using __bool_constant = integral_constant<bool, __v>;
94 
95 #if __cplusplus > 201402L
96 # define __cpp_lib_bool_constant 201505
97  template<bool __v>
98  using bool_constant = integral_constant<bool, __v>;
99 #endif
100 
101  // Meta programming helper types.
102 
103  template<bool, typename, typename>
104  struct conditional;
105 
106  template<typename...>
107  struct __or_;
108 
109  template<>
110  struct __or_<>
111  : public false_type
112  { };
113 
114  template<typename _B1>
115  struct __or_<_B1>
116  : public _B1
117  { };
118 
119  template<typename _B1, typename _B2>
120  struct __or_<_B1, _B2>
121  : public conditional<_B1::value, _B1, _B2>::type
122  { };
123 
124  template<typename _B1, typename _B2, typename _B3, typename... _Bn>
125  struct __or_<_B1, _B2, _B3, _Bn...>
126  : public conditional<_B1::value, _B1, __or_<_B2, _B3, _Bn...>>::type
127  { };
128 
129  template<typename...>
130  struct __and_;
131 
132  template<>
133  struct __and_<>
134  : public true_type
135  { };
136 
137  template<typename _B1>
138  struct __and_<_B1>
139  : public _B1
140  { };
141 
142  template<typename _B1, typename _B2>
143  struct __and_<_B1, _B2>
144  : public conditional<_B1::value, _B2, _B1>::type
145  { };
146 
147  template<typename _B1, typename _B2, typename _B3, typename... _Bn>
148  struct __and_<_B1, _B2, _B3, _Bn...>
149  : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
150  { };
151 
152  template<typename _Pp>
153  struct __not_
154  : public __bool_constant<!bool(_Pp::value)>
155  { };
156 
157 #if __cplusplus >= 201703L
158 
159 #define __cpp_lib_logical_traits 201510
160 
161  template<typename... _Bn>
162  struct conjunction
163  : __and_<_Bn...>
164  { };
165 
166  template<typename... _Bn>
167  struct disjunction
168  : __or_<_Bn...>
169  { };
170 
171  template<typename _Pp>
172  struct negation
173  : __not_<_Pp>
174  { };
175 
176  template<typename... _Bn>
177  inline constexpr bool conjunction_v = conjunction<_Bn...>::value;
178 
179  template<typename... _Bn>
180  inline constexpr bool disjunction_v = disjunction<_Bn...>::value;
181 
182  template<typename _Pp>
183  inline constexpr bool negation_v = negation<_Pp>::value;
184 
185 #endif // C++17
186 
187  // For several sfinae-friendly trait implementations we transport both the
188  // result information (as the member type) and the failure information (no
189  // member type). This is very similar to std::enable_if, but we cannot use
190  // them, because we need to derive from them as an implementation detail.
191 
192  template<typename _Tp>
193  struct __success_type
194  { typedef _Tp type; };
195 
196  struct __failure_type
197  { };
198 
199  // Primary type categories.
200 
201  template<typename>
202  struct remove_cv;
203 
204  template<typename>
205  struct __is_void_helper
206  : public false_type { };
207 
208  template<>
209  struct __is_void_helper<void>
210  : public true_type { };
211 
212  /// is_void
213  template<typename _Tp>
214  struct is_void
215  : public __is_void_helper<typename remove_cv<_Tp>::type>::type
216  { };
217 
218  template<typename>
219  struct __is_integral_helper
220  : public false_type { };
221 
222  template<>
223  struct __is_integral_helper<bool>
224  : public true_type { };
225 
226  template<>
227  struct __is_integral_helper<char>
228  : public true_type { };
229 
230  template<>
231  struct __is_integral_helper<signed char>
232  : public true_type { };
233 
234  template<>
235  struct __is_integral_helper<unsigned char>
236  : public true_type { };
237 
238 #ifdef _GLIBCXX_USE_WCHAR_T
239  template<>
240  struct __is_integral_helper<wchar_t>
241  : public true_type { };
242 #endif
243 
244  template<>
245  struct __is_integral_helper<char16_t>
246  : public true_type { };
247 
248  template<>
249  struct __is_integral_helper<char32_t>
250  : public true_type { };
251 
252  template<>
253  struct __is_integral_helper<short>
254  : public true_type { };
255 
256  template<>
257  struct __is_integral_helper<unsigned short>
258  : public true_type { };
259 
260  template<>
261  struct __is_integral_helper<int>
262  : public true_type { };
263 
264  template<>
265  struct __is_integral_helper<unsigned int>
266  : public true_type { };
267 
268  template<>
269  struct __is_integral_helper<long>
270  : public true_type { };
271 
272  template<>
273  struct __is_integral_helper<unsigned long>
274  : public true_type { };
275 
276  template<>
277  struct __is_integral_helper<long long>
278  : public true_type { };
279 
280  template<>
281  struct __is_integral_helper<unsigned long long>
282  : public true_type { };
283 
284  // Conditionalizing on __STRICT_ANSI__ here will break any port that
285  // uses one of these types for size_t.
286 #if defined(__GLIBCXX_TYPE_INT_N_0)
287  template<>
288  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_0>
289  : public true_type { };
290 
291  template<>
292  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_0>
293  : public true_type { };
294 #endif
295 #if defined(__GLIBCXX_TYPE_INT_N_1)
296  template<>
297  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_1>
298  : public true_type { };
299 
300  template<>
301  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_1>
302  : public true_type { };
303 #endif
304 #if defined(__GLIBCXX_TYPE_INT_N_2)
305  template<>
306  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_2>
307  : public true_type { };
308 
309  template<>
310  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_2>
311  : public true_type { };
312 #endif
313 #if defined(__GLIBCXX_TYPE_INT_N_3)
314  template<>
315  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_3>
316  : public true_type { };
317 
318  template<>
319  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_3>
320  : public true_type { };
321 #endif
322 
323  /// is_integral
324  template<typename _Tp>
325  struct is_integral
326  : public __is_integral_helper<typename remove_cv<_Tp>::type>::type
327  { };
328 
329  template<typename>
330  struct __is_floating_point_helper
331  : public false_type { };
332 
333  template<>
334  struct __is_floating_point_helper<float>
335  : public true_type { };
336 
337  template<>
338  struct __is_floating_point_helper<double>
339  : public true_type { };
340 
341  template<>
342  struct __is_floating_point_helper<long double>
343  : public true_type { };
344 
345 #if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
346  template<>
347  struct __is_floating_point_helper<__float128>
348  : public true_type { };
349 #endif
350 
351  /// is_floating_point
352  template<typename _Tp>
353  struct is_floating_point
354  : public __is_floating_point_helper<typename remove_cv<_Tp>::type>::type
355  { };
356 
357  /// is_array
358  template<typename>
359  struct is_array
360  : public false_type { };
361 
362  template<typename _Tp, std::size_t _Size>
363  struct is_array<_Tp[_Size]>
364  : public true_type { };
365 
366  template<typename _Tp>
367  struct is_array<_Tp[]>
368  : public true_type { };
369 
370  template<typename>
371  struct __is_pointer_helper
372  : public false_type { };
373 
374  template<typename _Tp>
375  struct __is_pointer_helper<_Tp*>
376  : public true_type { };
377 
378  /// is_pointer
379  template<typename _Tp>
380  struct is_pointer
381  : public __is_pointer_helper<typename remove_cv<_Tp>::type>::type
382  { };
383 
384  /// is_lvalue_reference
385  template<typename>
386  struct is_lvalue_reference
387  : public false_type { };
388 
389  template<typename _Tp>
390  struct is_lvalue_reference<_Tp&>
391  : public true_type { };
392 
393  /// is_rvalue_reference
394  template<typename>
395  struct is_rvalue_reference
396  : public false_type { };
397 
398  template<typename _Tp>
399  struct is_rvalue_reference<_Tp&&>
400  : public true_type { };
401 
402  template<typename>
403  struct is_function;
404 
405  template<typename>
406  struct __is_member_object_pointer_helper
407  : public false_type { };
408 
409  template<typename _Tp, typename _Cp>
410  struct __is_member_object_pointer_helper<_Tp _Cp::*>
411  : public integral_constant<bool, !is_function<_Tp>::value> { };
412 
413  /// is_member_object_pointer
414  template<typename _Tp>
415  struct is_member_object_pointer
416  : public __is_member_object_pointer_helper<
417  typename remove_cv<_Tp>::type>::type
418  { };
419 
420  template<typename>
421  struct __is_member_function_pointer_helper
422  : public false_type { };
423 
424  template<typename _Tp, typename _Cp>
425  struct __is_member_function_pointer_helper<_Tp _Cp::*>
426  : public integral_constant<bool, is_function<_Tp>::value> { };
427 
428  /// is_member_function_pointer
429  template<typename _Tp>
430  struct is_member_function_pointer
431  : public __is_member_function_pointer_helper<
432  typename remove_cv<_Tp>::type>::type
433  { };
434 
435  /// is_enum
436  template<typename _Tp>
437  struct is_enum
438  : public integral_constant<bool, __is_enum(_Tp)>
439  { };
440 
441  /// is_union
442  template<typename _Tp>
443  struct is_union
444  : public integral_constant<bool, __is_union(_Tp)>
445  { };
446 
447  /// is_class
448  template<typename _Tp>
449  struct is_class
450  : public integral_constant<bool, __is_class(_Tp)>
451  { };
452 
453  /// is_function
454  template<typename>
455  struct is_function
456  : public false_type { };
457 
458  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
459  struct is_function<_Res(_ArgTypes...) _GLIBCXX_NOEXCEPT_QUAL>
460  : public true_type { };
461 
462  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
463  struct is_function<_Res(_ArgTypes...) & _GLIBCXX_NOEXCEPT_QUAL>
464  : public true_type { };
465 
466  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
467  struct is_function<_Res(_ArgTypes...) && _GLIBCXX_NOEXCEPT_QUAL>
468  : public true_type { };
469 
470  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
471  struct is_function<_Res(_ArgTypes......) _GLIBCXX_NOEXCEPT_QUAL>
472  : public true_type { };
473 
474  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
475  struct is_function<_Res(_ArgTypes......) & _GLIBCXX_NOEXCEPT_QUAL>
476  : public true_type { };
477 
478  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
479  struct is_function<_Res(_ArgTypes......) && _GLIBCXX_NOEXCEPT_QUAL>
480  : public true_type { };
481 
482  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
483  struct is_function<_Res(_ArgTypes...) const _GLIBCXX_NOEXCEPT_QUAL>
484  : public true_type { };
485 
486  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
487  struct is_function<_Res(_ArgTypes...) const & _GLIBCXX_NOEXCEPT_QUAL>
488  : public true_type { };
489 
490  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
491  struct is_function<_Res(_ArgTypes...) const && _GLIBCXX_NOEXCEPT_QUAL>
492  : public true_type { };
493 
494  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
495  struct is_function<_Res(_ArgTypes......) const _GLIBCXX_NOEXCEPT_QUAL>
496  : public true_type { };
497 
498  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
499  struct is_function<_Res(_ArgTypes......) const & _GLIBCXX_NOEXCEPT_QUAL>
500  : public true_type { };
501 
502  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
503  struct is_function<_Res(_ArgTypes......) const && _GLIBCXX_NOEXCEPT_QUAL>
504  : public true_type { };
505 
506  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
507  struct is_function<_Res(_ArgTypes...) volatile _GLIBCXX_NOEXCEPT_QUAL>
508  : public true_type { };
509 
510  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
511  struct is_function<_Res(_ArgTypes...) volatile & _GLIBCXX_NOEXCEPT_QUAL>
512  : public true_type { };
513 
514  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
515  struct is_function<_Res(_ArgTypes...) volatile && _GLIBCXX_NOEXCEPT_QUAL>
516  : public true_type { };
517 
518  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
519  struct is_function<_Res(_ArgTypes......) volatile _GLIBCXX_NOEXCEPT_QUAL>
520  : public true_type { };
521 
522  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
523  struct is_function<_Res(_ArgTypes......) volatile & _GLIBCXX_NOEXCEPT_QUAL>
524  : public true_type { };
525 
526  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
527  struct is_function<_Res(_ArgTypes......) volatile && _GLIBCXX_NOEXCEPT_QUAL>
528  : public true_type { };
529 
530  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
531  struct is_function<_Res(_ArgTypes...) const volatile _GLIBCXX_NOEXCEPT_QUAL>
532  : public true_type { };
533 
534  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
535  struct is_function<_Res(_ArgTypes...) const volatile & _GLIBCXX_NOEXCEPT_QUAL>
536  : public true_type { };
537 
538  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
539  struct is_function<_Res(_ArgTypes...) const volatile && _GLIBCXX_NOEXCEPT_QUAL>
540  : public true_type { };
541 
542  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
543  struct is_function<_Res(_ArgTypes......) const volatile _GLIBCXX_NOEXCEPT_QUAL>
544  : public true_type { };
545 
546  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
547  struct is_function<_Res(_ArgTypes......) const volatile & _GLIBCXX_NOEXCEPT_QUAL>
548  : public true_type { };
549 
550  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
551  struct is_function<_Res(_ArgTypes......) const volatile && _GLIBCXX_NOEXCEPT_QUAL>
552  : public true_type { };
553 
554 #define __cpp_lib_is_null_pointer 201309
555 
556  template<typename>
557  struct __is_null_pointer_helper
558  : public false_type { };
559 
560  template<>
561  struct __is_null_pointer_helper<std::nullptr_t>
562  : public true_type { };
563 
564  /// is_null_pointer (LWG 2247).
565  template<typename _Tp>
566  struct is_null_pointer
567  : public __is_null_pointer_helper<typename remove_cv<_Tp>::type>::type
568  { };
569 
570  /// __is_nullptr_t (extension).
571  template<typename _Tp>
572  struct __is_nullptr_t
573  : public is_null_pointer<_Tp>
574  { };
575 
576  // Composite type categories.
577 
578  /// is_reference
579  template<typename _Tp>
580  struct is_reference
581  : public __or_<is_lvalue_reference<_Tp>,
582  is_rvalue_reference<_Tp>>::type
583  { };
584 
585  /// is_arithmetic
586  template<typename _Tp>
587  struct is_arithmetic
588  : public __or_<is_integral<_Tp>, is_floating_point<_Tp>>::type
589  { };
590 
591  /// is_fundamental
592  template<typename _Tp>
593  struct is_fundamental
594  : public __or_<is_arithmetic<_Tp>, is_void<_Tp>,
595  is_null_pointer<_Tp>>::type
596  { };
597 
598  /// is_object
599  template<typename _Tp>
600  struct is_object
601  : public __not_<__or_<is_function<_Tp>, is_reference<_Tp>,
602  is_void<_Tp>>>::type
603  { };
604 
605  template<typename>
606  struct is_member_pointer;
607 
608  /// is_scalar
609  template<typename _Tp>
610  struct is_scalar
611  : public __or_<is_arithmetic<_Tp>, is_enum<_Tp>, is_pointer<_Tp>,
612  is_member_pointer<_Tp>, is_null_pointer<_Tp>>::type
613  { };
614 
615  /// is_compound
616  template<typename _Tp>
617  struct is_compound
618  : public integral_constant<bool, !is_fundamental<_Tp>::value> { };
619 
620  template<typename _Tp>
621  struct __is_member_pointer_helper
622  : public false_type { };
623 
624  template<typename _Tp, typename _Cp>
625  struct __is_member_pointer_helper<_Tp _Cp::*>
626  : public true_type { };
627 
628  /// is_member_pointer
629  template<typename _Tp>
630  struct is_member_pointer
631  : public __is_member_pointer_helper<typename remove_cv<_Tp>::type>::type
632  { };
633 
634  // Utility to detect referenceable types ([defns.referenceable]).
635 
636  template<typename _Tp>
637  struct __is_referenceable
638  : public __or_<is_object<_Tp>, is_reference<_Tp>>::type
639  { };
640 
641  template<typename _Res, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
642  struct __is_referenceable<_Res(_Args...) _GLIBCXX_NOEXCEPT_QUAL>
643  : public true_type
644  { };
645 
646  template<typename _Res, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
647  struct __is_referenceable<_Res(_Args......) _GLIBCXX_NOEXCEPT_QUAL>
648  : public true_type
649  { };
650 
651  // Type properties.
652 
653  /// is_const
654  template<typename>
655  struct is_const
656  : public false_type { };
657 
658  template<typename _Tp>
659  struct is_const<_Tp const>
660  : public true_type { };
661 
662  /// is_volatile
663  template<typename>
664  struct is_volatile
665  : public false_type { };
666 
667  template<typename _Tp>
668  struct is_volatile<_Tp volatile>
669  : public true_type { };
670 
671  /// is_trivial
672  template<typename _Tp>
673  struct is_trivial
674  : public integral_constant<bool, __is_trivial(_Tp)>
675  { };
676 
677  // is_trivially_copyable
678  template<typename _Tp>
679  struct is_trivially_copyable
680  : public integral_constant<bool, __is_trivially_copyable(_Tp)>
681  { };
682 
683  /// is_standard_layout
684  template<typename _Tp>
685  struct is_standard_layout
686  : public integral_constant<bool, __is_standard_layout(_Tp)>
687  { };
688 
689  /// is_pod
690  // Could use is_standard_layout && is_trivial instead of the builtin.
691  template<typename _Tp>
692  struct is_pod
693  : public integral_constant<bool, __is_pod(_Tp)>
694  { };
695 
696  /// is_literal_type
697  template<typename _Tp>
698  struct is_literal_type
699  : public integral_constant<bool, __is_literal_type(_Tp)>
700  { };
701 
702  /// is_empty
703  template<typename _Tp>
704  struct is_empty
705  : public integral_constant<bool, __is_empty(_Tp)>
706  { };
707 
708  /// is_polymorphic
709  template<typename _Tp>
710  struct is_polymorphic
711  : public integral_constant<bool, __is_polymorphic(_Tp)>
712  { };
713 
714 #if __cplusplus >= 201402L
715 #define __cpp_lib_is_final 201402L
716  /// is_final
717  template<typename _Tp>
718  struct is_final
719  : public integral_constant<bool, __is_final(_Tp)>
720  { };
721 #endif
722 
723  /// is_abstract
724  template<typename _Tp>
725  struct is_abstract
726  : public integral_constant<bool, __is_abstract(_Tp)>
727  { };
728 
729  template<typename _Tp,
730  bool = is_arithmetic<_Tp>::value>
731  struct __is_signed_helper
732  : public false_type { };
733 
734  template<typename _Tp>
735  struct __is_signed_helper<_Tp, true>
736  : public integral_constant<bool, _Tp(-1) < _Tp(0)>
737  { };
738 
739  /// is_signed
740  template<typename _Tp>
741  struct is_signed
742  : public __is_signed_helper<_Tp>::type
743  { };
744 
745  /// is_unsigned
746  template<typename _Tp>
747  struct is_unsigned
748  : public __and_<is_arithmetic<_Tp>, __not_<is_signed<_Tp>>>
749  { };
750 
751 
752  // Destructible and constructible type properties.
753 
754  /**
755  * @brief Utility to simplify expressions used in unevaluated operands
756  * @ingroup utilities
757  */
758 
759  template<typename _Tp, typename _Up = _Tp&&>
760  _Up
761  __declval(int);
762 
763  template<typename _Tp>
764  _Tp
765  __declval(long);
766 
767  template<typename _Tp>
768  auto declval() noexcept -> decltype(__declval<_Tp>(0));
769 
770  template<typename, unsigned = 0>
771  struct extent;
772 
773  template<typename>
774  struct remove_all_extents;
775 
776  template<typename _Tp>
777  struct __is_array_known_bounds
778  : public integral_constant<bool, (extent<_Tp>::value > 0)>
779  { };
780 
781  template<typename _Tp>
782  struct __is_array_unknown_bounds
783  : public __and_<is_array<_Tp>, __not_<extent<_Tp>>>
784  { };
785 
786  // In N3290 is_destructible does not say anything about function
787  // types and abstract types, see LWG 2049. This implementation
788  // describes function types as non-destructible and all complete
789  // object types as destructible, iff the explicit destructor
790  // call expression is wellformed.
791  struct __do_is_destructible_impl
792  {
793  template<typename _Tp, typename = decltype(declval<_Tp&>().~_Tp())>
794  static true_type __test(int);
795 
796  template<typename>
797  static false_type __test(...);
798  };
799 
800  template<typename _Tp>
801  struct __is_destructible_impl
802  : public __do_is_destructible_impl
803  {
804  typedef decltype(__test<_Tp>(0)) type;
805  };
806 
807  template<typename _Tp,
808  bool = __or_<is_void<_Tp>,
809  __is_array_unknown_bounds<_Tp>,
810  is_function<_Tp>>::value,
811  bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
812  struct __is_destructible_safe;
813 
814  template<typename _Tp>
815  struct __is_destructible_safe<_Tp, false, false>
816  : public __is_destructible_impl<typename
817  remove_all_extents<_Tp>::type>::type
818  { };
819 
820  template<typename _Tp>
821  struct __is_destructible_safe<_Tp, true, false>
822  : public false_type { };
823 
824  template<typename _Tp>
825  struct __is_destructible_safe<_Tp, false, true>
826  : public true_type { };
827 
828  /// is_destructible
829  template<typename _Tp>
830  struct is_destructible
831  : public __is_destructible_safe<_Tp>::type
832  { };
833 
834  // is_nothrow_destructible requires that is_destructible is
835  // satisfied as well. We realize that by mimicing the
836  // implementation of is_destructible but refer to noexcept(expr)
837  // instead of decltype(expr).
838  struct __do_is_nt_destructible_impl
839  {
840  template<typename _Tp>
841  static integral_constant<bool, noexcept(declval<_Tp&>().~_Tp())>
842  __test(int);
843 
844  template<typename>
845  static false_type __test(...);
846  };
847 
848  template<typename _Tp>
849  struct __is_nt_destructible_impl
850  : public __do_is_nt_destructible_impl
851  {
852  typedef decltype(__test<_Tp>(0)) type;
853  };
854 
855  template<typename _Tp,
856  bool = __or_<is_void<_Tp>,
857  __is_array_unknown_bounds<_Tp>,
858  is_function<_Tp>>::value,
859  bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
860  struct __is_nt_destructible_safe;
861 
862  template<typename _Tp>
863  struct __is_nt_destructible_safe<_Tp, false, false>
864  : public __is_nt_destructible_impl<typename
865  remove_all_extents<_Tp>::type>::type
866  { };
867 
868  template<typename _Tp>
869  struct __is_nt_destructible_safe<_Tp, true, false>
870  : public false_type { };
871 
872  template<typename _Tp>
873  struct __is_nt_destructible_safe<_Tp, false, true>
874  : public true_type { };
875 
876  /// is_nothrow_destructible
877  template<typename _Tp>
878  struct is_nothrow_destructible
879  : public __is_nt_destructible_safe<_Tp>::type
880  { };
881 
882  struct __do_is_default_constructible_impl
883  {
884  template<typename _Tp, typename = decltype(_Tp())>
885  static true_type __test(int);
886 
887  template<typename>
888  static false_type __test(...);
889  };
890 
891  template<typename _Tp>
892  struct __is_default_constructible_impl
893  : public __do_is_default_constructible_impl
894  {
895  typedef decltype(__test<_Tp>(0)) type;
896  };
897 
898  template<typename _Tp>
899  struct __is_default_constructible_atom
900  : public __and_<__not_<is_void<_Tp>>,
901  __is_default_constructible_impl<_Tp>>
902  { };
903 
904  template<typename _Tp, bool = is_array<_Tp>::value>
905  struct __is_default_constructible_safe;
906 
907  // The following technique is a workaround for a current core language
908  // restriction, which does not allow for array types to occur in
909  // functional casts of the form T(). Complete arrays can be default-
910  // constructed, if the element type is default-constructible, but
911  // arrays with unknown bounds are not.
912  template<typename _Tp>
913  struct __is_default_constructible_safe<_Tp, true>
914  : public __and_<__is_array_known_bounds<_Tp>,
915  __is_default_constructible_atom<typename
916  remove_all_extents<_Tp>::type>>
917  { };
918 
919  template<typename _Tp>
920  struct __is_default_constructible_safe<_Tp, false>
921  : public __is_default_constructible_atom<_Tp>::type
922  { };
923 
924  /// is_default_constructible
925  template<typename _Tp>
926  struct is_default_constructible
927  : public __is_default_constructible_safe<_Tp>::type
928  { };
929 
930  /// is_constructible
931  template<typename _Tp, typename... _Args>
932  struct is_constructible
933  : public __bool_constant<__is_constructible(_Tp, _Args...)>
934  { };
935 
936  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
937  struct __is_copy_constructible_impl;
938 
939  template<typename _Tp>
940  struct __is_copy_constructible_impl<_Tp, false>
941  : public false_type { };
942 
943  template<typename _Tp>
944  struct __is_copy_constructible_impl<_Tp, true>
945  : public is_constructible<_Tp, const _Tp&>
946  { };
947 
948  /// is_copy_constructible
949  template<typename _Tp>
950  struct is_copy_constructible
951  : public __is_copy_constructible_impl<_Tp>
952  { };
953 
954  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
955  struct __is_move_constructible_impl;
956 
957  template<typename _Tp>
958  struct __is_move_constructible_impl<_Tp, false>
959  : public false_type { };
960 
961  template<typename _Tp>
962  struct __is_move_constructible_impl<_Tp, true>
963  : public is_constructible<_Tp, _Tp&&>
964  { };
965 
966  /// is_move_constructible
967  template<typename _Tp>
968  struct is_move_constructible
969  : public __is_move_constructible_impl<_Tp>
970  { };
971 
972  template<typename _Tp>
973  struct __is_nt_default_constructible_atom
974  : public integral_constant<bool, noexcept(_Tp())>
975  { };
976 
977  template<typename _Tp, bool = is_array<_Tp>::value>
978  struct __is_nt_default_constructible_impl;
979 
980  template<typename _Tp>
981  struct __is_nt_default_constructible_impl<_Tp, true>
982  : public __and_<__is_array_known_bounds<_Tp>,
983  __is_nt_default_constructible_atom<typename
984  remove_all_extents<_Tp>::type>>
985  { };
986 
987  template<typename _Tp>
988  struct __is_nt_default_constructible_impl<_Tp, false>
989  : public __is_nt_default_constructible_atom<_Tp>
990  { };
991 
992  /// is_nothrow_default_constructible
993  template<typename _Tp>
994  struct is_nothrow_default_constructible
995  : public __and_<is_default_constructible<_Tp>,
996  __is_nt_default_constructible_impl<_Tp>>
997  { };
998 
999  template<typename _Tp, typename... _Args>
1000  struct __is_nt_constructible_impl
1001  : public integral_constant<bool, noexcept(_Tp(declval<_Args>()...))>
1002  { };
1003 
1004  template<typename _Tp, typename _Arg>
1005  struct __is_nt_constructible_impl<_Tp, _Arg>
1006  : public integral_constant<bool,
1007  noexcept(static_cast<_Tp>(declval<_Arg>()))>
1008  { };
1009 
1010  template<typename _Tp>
1011  struct __is_nt_constructible_impl<_Tp>
1012  : public is_nothrow_default_constructible<_Tp>
1013  { };
1014 
1015  /// is_nothrow_constructible
1016  template<typename _Tp, typename... _Args>
1017  struct is_nothrow_constructible
1018  : public __and_<is_constructible<_Tp, _Args...>,
1019  __is_nt_constructible_impl<_Tp, _Args...>>
1020  { };
1021 
1022  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1023  struct __is_nothrow_copy_constructible_impl;
1024 
1025  template<typename _Tp>
1026  struct __is_nothrow_copy_constructible_impl<_Tp, false>
1027  : public false_type { };
1028 
1029  template<typename _Tp>
1030  struct __is_nothrow_copy_constructible_impl<_Tp, true>
1031  : public is_nothrow_constructible<_Tp, const _Tp&>
1032  { };
1033 
1034  /// is_nothrow_copy_constructible
1035  template<typename _Tp>
1036  struct is_nothrow_copy_constructible
1037  : public __is_nothrow_copy_constructible_impl<_Tp>
1038  { };
1039 
1040  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1041  struct __is_nothrow_move_constructible_impl;
1042 
1043  template<typename _Tp>
1044  struct __is_nothrow_move_constructible_impl<_Tp, false>
1045  : public false_type { };
1046 
1047  template<typename _Tp>
1048  struct __is_nothrow_move_constructible_impl<_Tp, true>
1049  : public is_nothrow_constructible<_Tp, _Tp&&>
1050  { };
1051 
1052  /// is_nothrow_move_constructible
1053  template<typename _Tp>
1054  struct is_nothrow_move_constructible
1055  : public __is_nothrow_move_constructible_impl<_Tp>
1056  { };
1057 
1058  /// is_assignable
1059  template<typename _Tp, typename _Up>
1060  struct is_assignable
1061  : public __bool_constant<__is_assignable(_Tp, _Up)>
1062  { };
1063 
1064  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1065  struct __is_copy_assignable_impl;
1066 
1067  template<typename _Tp>
1068  struct __is_copy_assignable_impl<_Tp, false>
1069  : public false_type { };
1070 
1071  template<typename _Tp>
1072  struct __is_copy_assignable_impl<_Tp, true>
1073  : public is_assignable<_Tp&, const _Tp&>
1074  { };
1075 
1076  /// is_copy_assignable
1077  template<typename _Tp>
1078  struct is_copy_assignable
1079  : public __is_copy_assignable_impl<_Tp>
1080  { };
1081 
1082  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1083  struct __is_move_assignable_impl;
1084 
1085  template<typename _Tp>
1086  struct __is_move_assignable_impl<_Tp, false>
1087  : public false_type { };
1088 
1089  template<typename _Tp>
1090  struct __is_move_assignable_impl<_Tp, true>
1091  : public is_assignable<_Tp&, _Tp&&>
1092  { };
1093 
1094  /// is_move_assignable
1095  template<typename _Tp>
1096  struct is_move_assignable
1097  : public __is_move_assignable_impl<_Tp>
1098  { };
1099 
1100  template<typename _Tp, typename _Up>
1101  struct __is_nt_assignable_impl
1102  : public integral_constant<bool, noexcept(declval<_Tp>() = declval<_Up>())>
1103  { };
1104 
1105  /// is_nothrow_assignable
1106  template<typename _Tp, typename _Up>
1107  struct is_nothrow_assignable
1108  : public __and_<is_assignable<_Tp, _Up>,
1109  __is_nt_assignable_impl<_Tp, _Up>>
1110  { };
1111 
1112  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1113  struct __is_nt_copy_assignable_impl;
1114 
1115  template<typename _Tp>
1116  struct __is_nt_copy_assignable_impl<_Tp, false>
1117  : public false_type { };
1118 
1119  template<typename _Tp>
1120  struct __is_nt_copy_assignable_impl<_Tp, true>
1121  : public is_nothrow_assignable<_Tp&, const _Tp&>
1122  { };
1123 
1124  /// is_nothrow_copy_assignable
1125  template<typename _Tp>
1126  struct is_nothrow_copy_assignable
1127  : public __is_nt_copy_assignable_impl<_Tp>
1128  { };
1129 
1130  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1131  struct __is_nt_move_assignable_impl;
1132 
1133  template<typename _Tp>
1134  struct __is_nt_move_assignable_impl<_Tp, false>
1135  : public false_type { };
1136 
1137  template<typename _Tp>
1138  struct __is_nt_move_assignable_impl<_Tp, true>
1139  : public is_nothrow_assignable<_Tp&, _Tp&&>
1140  { };
1141 
1142  /// is_nothrow_move_assignable
1143  template<typename _Tp>
1144  struct is_nothrow_move_assignable
1145  : public __is_nt_move_assignable_impl<_Tp>
1146  { };
1147 
1148  /// is_trivially_constructible
1149  template<typename _Tp, typename... _Args>
1150  struct is_trivially_constructible
1151  : public __bool_constant<__is_trivially_constructible(_Tp, _Args...)>
1152  { };
1153 
1154  /// is_trivially_default_constructible
1155  template<typename _Tp>
1156  struct is_trivially_default_constructible
1157  : public is_trivially_constructible<_Tp>::type
1158  { };
1159 
1160  struct __do_is_implicitly_default_constructible_impl
1161  {
1162  template <typename _Tp>
1163  static void __helper(const _Tp&);
1164 
1165  template <typename _Tp>
1166  static true_type __test(const _Tp&,
1167  decltype(__helper<const _Tp&>({}))* = 0);
1168 
1169  static false_type __test(...);
1170  };
1171 
1172  template<typename _Tp>
1173  struct __is_implicitly_default_constructible_impl
1174  : public __do_is_implicitly_default_constructible_impl
1175  {
1176  typedef decltype(__test(declval<_Tp>())) type;
1177  };
1178 
1179  template<typename _Tp>
1180  struct __is_implicitly_default_constructible_safe
1181  : public __is_implicitly_default_constructible_impl<_Tp>::type
1182  { };
1183 
1184  template <typename _Tp>
1185  struct __is_implicitly_default_constructible
1186  : public __and_<is_default_constructible<_Tp>,
1187  __is_implicitly_default_constructible_safe<_Tp>>
1188  { };
1189 
1190  /// is_trivially_copy_constructible
1191 
1192  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1193  struct __is_trivially_copy_constructible_impl;
1194 
1195  template<typename _Tp>
1196  struct __is_trivially_copy_constructible_impl<_Tp, false>
1197  : public false_type { };
1198 
1199  template<typename _Tp>
1200  struct __is_trivially_copy_constructible_impl<_Tp, true>
1201  : public __and_<is_copy_constructible<_Tp>,
1202  integral_constant<bool,
1203  __is_trivially_constructible(_Tp, const _Tp&)>>
1204  { };
1205 
1206  template<typename _Tp>
1207  struct is_trivially_copy_constructible
1208  : public __is_trivially_copy_constructible_impl<_Tp>
1209  { };
1210 
1211  /// is_trivially_move_constructible
1212 
1213  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1214  struct __is_trivially_move_constructible_impl;
1215 
1216  template<typename _Tp>
1217  struct __is_trivially_move_constructible_impl<_Tp, false>
1218  : public false_type { };
1219 
1220  template<typename _Tp>
1221  struct __is_trivially_move_constructible_impl<_Tp, true>
1222  : public __and_<is_move_constructible<_Tp>,
1223  integral_constant<bool,
1224  __is_trivially_constructible(_Tp, _Tp&&)>>
1225  { };
1226 
1227  template<typename _Tp>
1228  struct is_trivially_move_constructible
1229  : public __is_trivially_move_constructible_impl<_Tp>
1230  { };
1231 
1232  /// is_trivially_assignable
1233  template<typename _Tp, typename _Up>
1234  struct is_trivially_assignable
1235  : public __bool_constant<__is_trivially_assignable(_Tp, _Up)>
1236  { };
1237 
1238  /// is_trivially_copy_assignable
1239 
1240  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1241  struct __is_trivially_copy_assignable_impl;
1242 
1243  template<typename _Tp>
1244  struct __is_trivially_copy_assignable_impl<_Tp, false>
1245  : public false_type { };
1246 
1247  template<typename _Tp>
1248  struct __is_trivially_copy_assignable_impl<_Tp, true>
1249  : public __and_<is_copy_assignable<_Tp>,
1250  integral_constant<bool,
1251  __is_trivially_assignable(_Tp&, const _Tp&)>>
1252  { };
1253 
1254  template<typename _Tp>
1255  struct is_trivially_copy_assignable
1256  : public __is_trivially_copy_assignable_impl<_Tp>
1257  { };
1258 
1259  /// is_trivially_move_assignable
1260 
1261  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1262  struct __is_trivially_move_assignable_impl;
1263 
1264  template<typename _Tp>
1265  struct __is_trivially_move_assignable_impl<_Tp, false>
1266  : public false_type { };
1267 
1268  template<typename _Tp>
1269  struct __is_trivially_move_assignable_impl<_Tp, true>
1270  : public __and_<is_move_assignable<_Tp>,
1271  integral_constant<bool,
1272  __is_trivially_assignable(_Tp&, _Tp&&)>>
1273  { };
1274 
1275  template<typename _Tp>
1276  struct is_trivially_move_assignable
1277  : public __is_trivially_move_assignable_impl<_Tp>
1278  { };
1279 
1280  /// is_trivially_destructible
1281  template<typename _Tp>
1282  struct is_trivially_destructible
1283  : public __and_<is_destructible<_Tp>, integral_constant<bool,
1284  __has_trivial_destructor(_Tp)>>
1285  { };
1286 
1287 
1288  /// has_virtual_destructor
1289  template<typename _Tp>
1290  struct has_virtual_destructor
1291  : public integral_constant<bool, __has_virtual_destructor(_Tp)>
1292  { };
1293 
1294 
1295  // type property queries.
1296 
1297  /// alignment_of
1298  template<typename _Tp>
1299  struct alignment_of
1300  : public integral_constant<std::size_t, __alignof__(_Tp)> { };
1301 
1302  /// rank
1303  template<typename>
1304  struct rank
1305  : public integral_constant<std::size_t, 0> { };
1306 
1307  template<typename _Tp, std::size_t _Size>
1308  struct rank<_Tp[_Size]>
1309  : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
1310 
1311  template<typename _Tp>
1312  struct rank<_Tp[]>
1313  : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
1314 
1315  /// extent
1316  template<typename, unsigned _Uint>
1317  struct extent
1318  : public integral_constant<std::size_t, 0> { };
1319 
1320  template<typename _Tp, unsigned _Uint, std::size_t _Size>
1321  struct extent<_Tp[_Size], _Uint>
1322  : public integral_constant<std::size_t,
1323  _Uint == 0 ? _Size : extent<_Tp,
1324  _Uint - 1>::value>
1325  { };
1326 
1327  template<typename _Tp, unsigned _Uint>
1328  struct extent<_Tp[], _Uint>
1329  : public integral_constant<std::size_t,
1330  _Uint == 0 ? 0 : extent<_Tp,
1331  _Uint - 1>::value>
1332  { };
1333 
1334 
1335  // Type relations.
1336 
1337  /// is_same
1338  template<typename, typename>
1339  struct is_same
1340  : public false_type { };
1341 
1342  template<typename _Tp>
1343  struct is_same<_Tp, _Tp>
1344  : public true_type { };
1345 
1346  /// is_base_of
1347  template<typename _Base, typename _Derived>
1348  struct is_base_of
1349  : public integral_constant<bool, __is_base_of(_Base, _Derived)>
1350  { };
1351 
1352  template<typename _From, typename _To,
1353  bool = __or_<is_void<_From>, is_function<_To>,
1354  is_array<_To>>::value>
1355  struct __is_convertible_helper
1356  { typedef typename is_void<_To>::type type; };
1357 
1358  template<typename _From, typename _To>
1359  class __is_convertible_helper<_From, _To, false>
1360  {
1361  template<typename _To1>
1362  static void __test_aux(_To1);
1363 
1364  template<typename _From1, typename _To1,
1365  typename = decltype(__test_aux<_To1>(std::declval<_From1>()))>
1366  static true_type
1367  __test(int);
1368 
1369  template<typename, typename>
1370  static false_type
1371  __test(...);
1372 
1373  public:
1374  typedef decltype(__test<_From, _To>(0)) type;
1375  };
1376 
1377 
1378  /// is_convertible
1379  template<typename _From, typename _To>
1380  struct is_convertible
1381  : public __is_convertible_helper<_From, _To>::type
1382  { };
1383 
1384 
1385  // Const-volatile modifications.
1386 
1387  /// remove_const
1388  template<typename _Tp>
1389  struct remove_const
1390  { typedef _Tp type; };
1391 
1392  template<typename _Tp>
1393  struct remove_const<_Tp const>
1394  { typedef _Tp type; };
1395 
1396  /// remove_volatile
1397  template<typename _Tp>
1398  struct remove_volatile
1399  { typedef _Tp type; };
1400 
1401  template<typename _Tp>
1402  struct remove_volatile<_Tp volatile>
1403  { typedef _Tp type; };
1404 
1405  /// remove_cv
1406  template<typename _Tp>
1407  struct remove_cv
1408  {
1409  typedef typename
1410  remove_const<typename remove_volatile<_Tp>::type>::type type;
1411  };
1412 
1413  /// add_const
1414  template<typename _Tp>
1415  struct add_const
1416  { typedef _Tp const type; };
1417 
1418  /// add_volatile
1419  template<typename _Tp>
1420  struct add_volatile
1421  { typedef _Tp volatile type; };
1422 
1423  /// add_cv
1424  template<typename _Tp>
1425  struct add_cv
1426  {
1427  typedef typename
1428  add_const<typename add_volatile<_Tp>::type>::type type;
1429  };
1430 
1431 #if __cplusplus > 201103L
1432 
1433 #define __cpp_lib_transformation_trait_aliases 201304
1434 
1435  /// Alias template for remove_const
1436  template<typename _Tp>
1437  using remove_const_t = typename remove_const<_Tp>::type;
1438 
1439  /// Alias template for remove_volatile
1440  template<typename _Tp>
1441  using remove_volatile_t = typename remove_volatile<_Tp>::type;
1442 
1443  /// Alias template for remove_cv
1444  template<typename _Tp>
1445  using remove_cv_t = typename remove_cv<_Tp>::type;
1446 
1447  /// Alias template for add_const
1448  template<typename _Tp>
1449  using add_const_t = typename add_const<_Tp>::type;
1450 
1451  /// Alias template for add_volatile
1452  template<typename _Tp>
1453  using add_volatile_t = typename add_volatile<_Tp>::type;
1454 
1455  /// Alias template for add_cv
1456  template<typename _Tp>
1457  using add_cv_t = typename add_cv<_Tp>::type;
1458 #endif
1459 
1460  // Reference transformations.
1461 
1462  /// remove_reference
1463  template<typename _Tp>
1464  struct remove_reference
1465  { typedef _Tp type; };
1466 
1467  template<typename _Tp>
1468  struct remove_reference<_Tp&>
1469  { typedef _Tp type; };
1470 
1471  template<typename _Tp>
1472  struct remove_reference<_Tp&&>
1473  { typedef _Tp type; };
1474 
1475  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1476  struct __add_lvalue_reference_helper
1477  { typedef _Tp type; };
1478 
1479  template<typename _Tp>
1480  struct __add_lvalue_reference_helper<_Tp, true>
1481  { typedef _Tp& type; };
1482 
1483  /// add_lvalue_reference
1484  template<typename _Tp>
1485  struct add_lvalue_reference
1486  : public __add_lvalue_reference_helper<_Tp>
1487  { };
1488 
1489  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1490  struct __add_rvalue_reference_helper
1491  { typedef _Tp type; };
1492 
1493  template<typename _Tp>
1494  struct __add_rvalue_reference_helper<_Tp, true>
1495  { typedef _Tp&& type; };
1496 
1497  /// add_rvalue_reference
1498  template<typename _Tp>
1499  struct add_rvalue_reference
1500  : public __add_rvalue_reference_helper<_Tp>
1501  { };
1502 
1503 #if __cplusplus > 201103L
1504  /// Alias template for remove_reference
1505  template<typename _Tp>
1506  using remove_reference_t = typename remove_reference<_Tp>::type;
1507 
1508  /// Alias template for add_lvalue_reference
1509  template<typename _Tp>
1510  using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type;
1511 
1512  /// Alias template for add_rvalue_reference
1513  template<typename _Tp>
1514  using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type;
1515 #endif
1516 
1517  // Sign modifications.
1518 
1519  // Utility for constructing identically cv-qualified types.
1520  template<typename _Unqualified, bool _IsConst, bool _IsVol>
1521  struct __cv_selector;
1522 
1523  template<typename _Unqualified>
1524  struct __cv_selector<_Unqualified, false, false>
1525  { typedef _Unqualified __type; };
1526 
1527  template<typename _Unqualified>
1528  struct __cv_selector<_Unqualified, false, true>
1529  { typedef volatile _Unqualified __type; };
1530 
1531  template<typename _Unqualified>
1532  struct __cv_selector<_Unqualified, true, false>
1533  { typedef const _Unqualified __type; };
1534 
1535  template<typename _Unqualified>
1536  struct __cv_selector<_Unqualified, true, true>
1537  { typedef const volatile _Unqualified __type; };
1538 
1539  template<typename _Qualified, typename _Unqualified,
1540  bool _IsConst = is_const<_Qualified>::value,
1541  bool _IsVol = is_volatile<_Qualified>::value>
1542  class __match_cv_qualifiers
1543  {
1544  typedef __cv_selector<_Unqualified, _IsConst, _IsVol> __match;
1545 
1546  public:
1547  typedef typename __match::__type __type;
1548  };
1549 
1550  // Utility for finding the unsigned versions of signed integral types.
1551  template<typename _Tp>
1552  struct __make_unsigned
1553  { typedef _Tp __type; };
1554 
1555  template<>
1556  struct __make_unsigned<char>
1557  { typedef unsigned char __type; };
1558 
1559  template<>
1560  struct __make_unsigned<signed char>
1561  { typedef unsigned char __type; };
1562 
1563  template<>
1564  struct __make_unsigned<short>
1565  { typedef unsigned short __type; };
1566 
1567  template<>
1568  struct __make_unsigned<int>
1569  { typedef unsigned int __type; };
1570 
1571  template<>
1572  struct __make_unsigned<long>
1573  { typedef unsigned long __type; };
1574 
1575  template<>
1576  struct __make_unsigned<long long>
1577  { typedef unsigned long long __type; };
1578 
1579 #if defined(_GLIBCXX_USE_WCHAR_T) && !defined(__WCHAR_UNSIGNED__)
1580  template<>
1581  struct __make_unsigned<wchar_t> : __make_unsigned<__WCHAR_TYPE__>
1582  { };
1583 #endif
1584 
1585 #if defined(__GLIBCXX_TYPE_INT_N_0)
1586  template<>
1587  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_0>
1588  { typedef unsigned __GLIBCXX_TYPE_INT_N_0 __type; };
1589 #endif
1590 #if defined(__GLIBCXX_TYPE_INT_N_1)
1591  template<>
1592  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_1>
1593  { typedef unsigned __GLIBCXX_TYPE_INT_N_1 __type; };
1594 #endif
1595 #if defined(__GLIBCXX_TYPE_INT_N_2)
1596  template<>
1597  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_2>
1598  { typedef unsigned __GLIBCXX_TYPE_INT_N_2 __type; };
1599 #endif
1600 #if defined(__GLIBCXX_TYPE_INT_N_3)
1601  template<>
1602  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_3>
1603  { typedef unsigned __GLIBCXX_TYPE_INT_N_3 __type; };
1604 #endif
1605 
1606  // Select between integral and enum: not possible to be both.
1607  template<typename _Tp,
1608  bool _IsInt = is_integral<_Tp>::value,
1609  bool _IsEnum = is_enum<_Tp>::value>
1610  class __make_unsigned_selector;
1611 
1612  template<typename _Tp>
1613  class __make_unsigned_selector<_Tp, true, false>
1614  {
1615  typedef __make_unsigned<typename remove_cv<_Tp>::type> __unsignedt;
1616  typedef typename __unsignedt::__type __unsigned_type;
1617  typedef __match_cv_qualifiers<_Tp, __unsigned_type> __cv_unsigned;
1618 
1619  public:
1620  typedef typename __cv_unsigned::__type __type;
1621  };
1622 
1623  template<typename _Tp>
1624  class __make_unsigned_selector<_Tp, false, true>
1625  {
1626  // With -fshort-enums, an enum may be as small as a char.
1627  typedef unsigned char __smallest;
1628  static const bool __b0 = sizeof(_Tp) <= sizeof(__smallest);
1629  static const bool __b1 = sizeof(_Tp) <= sizeof(unsigned short);
1630  static const bool __b2 = sizeof(_Tp) <= sizeof(unsigned int);
1631  static const bool __b3 = sizeof(_Tp) <= sizeof(unsigned long);
1632  typedef conditional<__b3, unsigned long, unsigned long long> __cond3;
1633  typedef typename __cond3::type __cond3_type;
1634  typedef conditional<__b2, unsigned int, __cond3_type> __cond2;
1635  typedef typename __cond2::type __cond2_type;
1636  typedef conditional<__b1, unsigned short, __cond2_type> __cond1;
1637  typedef typename __cond1::type __cond1_type;
1638 
1639  typedef typename conditional<__b0, __smallest, __cond1_type>::type
1640  __unsigned_type;
1641  typedef __match_cv_qualifiers<_Tp, __unsigned_type> __cv_unsigned;
1642 
1643  public:
1644  typedef typename __cv_unsigned::__type __type;
1645  };
1646 
1647  // Given an integral/enum type, return the corresponding unsigned
1648  // integer type.
1649  // Primary template.
1650  /// make_unsigned
1651  template<typename _Tp>
1652  struct make_unsigned
1653  { typedef typename __make_unsigned_selector<_Tp>::__type type; };
1654 
1655  // Integral, but don't define.
1656  template<>
1657  struct make_unsigned<bool>;
1658 
1659 
1660  // Utility for finding the signed versions of unsigned integral types.
1661  template<typename _Tp>
1662  struct __make_signed
1663  { typedef _Tp __type; };
1664 
1665  template<>
1666  struct __make_signed<char>
1667  { typedef signed char __type; };
1668 
1669  template<>
1670  struct __make_signed<unsigned char>
1671  { typedef signed char __type; };
1672 
1673  template<>
1674  struct __make_signed<unsigned short>
1675  { typedef signed short __type; };
1676 
1677  template<>
1678  struct __make_signed<unsigned int>
1679  { typedef signed int __type; };
1680 
1681  template<>
1682  struct __make_signed<unsigned long>
1683  { typedef signed long __type; };
1684 
1685  template<>
1686  struct __make_signed<unsigned long long>
1687  { typedef signed long long __type; };
1688 
1689 #if defined(_GLIBCXX_USE_WCHAR_T) && defined(__WCHAR_UNSIGNED__)
1690  template<>
1691  struct __make_signed<wchar_t> : __make_signed<__WCHAR_TYPE__>
1692  { };
1693 #endif
1694 
1695 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
1696  template<>
1697  struct __make_signed<char16_t> : __make_signed<uint_least16_t>
1698  { };
1699  template<>
1700  struct __make_signed<char32_t> : __make_signed<uint_least32_t>
1701  { };
1702 #endif
1703 
1704 #if defined(__GLIBCXX_TYPE_INT_N_0)
1705  template<>
1706  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_0>
1707  { typedef __GLIBCXX_TYPE_INT_N_0 __type; };
1708 #endif
1709 #if defined(__GLIBCXX_TYPE_INT_N_1)
1710  template<>
1711  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_1>
1712  { typedef __GLIBCXX_TYPE_INT_N_1 __type; };
1713 #endif
1714 #if defined(__GLIBCXX_TYPE_INT_N_2)
1715  template<>
1716  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_2>
1717  { typedef __GLIBCXX_TYPE_INT_N_2 __type; };
1718 #endif
1719 #if defined(__GLIBCXX_TYPE_INT_N_3)
1720  template<>
1721  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_3>
1722  { typedef __GLIBCXX_TYPE_INT_N_3 __type; };
1723 #endif
1724 
1725  // Select between integral and enum: not possible to be both.
1726  template<typename _Tp,
1727  bool _IsInt = is_integral<_Tp>::value,
1728  bool _IsEnum = is_enum<_Tp>::value>
1729  class __make_signed_selector;
1730 
1731  template<typename _Tp>
1732  class __make_signed_selector<_Tp, true, false>
1733  {
1734  typedef __make_signed<typename remove_cv<_Tp>::type> __signedt;
1735  typedef typename __signedt::__type __signed_type;
1736  typedef __match_cv_qualifiers<_Tp, __signed_type> __cv_signed;
1737 
1738  public:
1739  typedef typename __cv_signed::__type __type;
1740  };
1741 
1742  template<typename _Tp>
1743  class __make_signed_selector<_Tp, false, true>
1744  {
1745  typedef typename __make_unsigned_selector<_Tp>::__type __unsigned_type;
1746 
1747  public:
1748  typedef typename __make_signed_selector<__unsigned_type>::__type __type;
1749  };
1750 
1751  // Given an integral/enum type, return the corresponding signed
1752  // integer type.
1753  // Primary template.
1754  /// make_signed
1755  template<typename _Tp>
1756  struct make_signed
1757  { typedef typename __make_signed_selector<_Tp>::__type type; };
1758 
1759  // Integral, but don't define.
1760  template<>
1761  struct make_signed<bool>;
1762 
1763 #if __cplusplus > 201103L
1764  /// Alias template for make_signed
1765  template<typename _Tp>
1766  using make_signed_t = typename make_signed<_Tp>::type;
1767 
1768  /// Alias template for make_unsigned
1769  template<typename _Tp>
1770  using make_unsigned_t = typename make_unsigned<_Tp>::type;
1771 #endif
1772 
1773  // Array modifications.
1774 
1775  /// remove_extent
1776  template<typename _Tp>
1777  struct remove_extent
1778  { typedef _Tp type; };
1779 
1780  template<typename _Tp, std::size_t _Size>
1781  struct remove_extent<_Tp[_Size]>
1782  { typedef _Tp type; };
1783 
1784  template<typename _Tp>
1785  struct remove_extent<_Tp[]>
1786  { typedef _Tp type; };
1787 
1788  /// remove_all_extents
1789  template<typename _Tp>
1790  struct remove_all_extents
1791  { typedef _Tp type; };
1792 
1793  template<typename _Tp, std::size_t _Size>
1794  struct remove_all_extents<_Tp[_Size]>
1795  { typedef typename remove_all_extents<_Tp>::type type; };
1796 
1797  template<typename _Tp>
1798  struct remove_all_extents<_Tp[]>
1799  { typedef typename remove_all_extents<_Tp>::type type; };
1800 
1801 #if __cplusplus > 201103L
1802  /// Alias template for remove_extent
1803  template<typename _Tp>
1804  using remove_extent_t = typename remove_extent<_Tp>::type;
1805 
1806  /// Alias template for remove_all_extents
1807  template<typename _Tp>
1808  using remove_all_extents_t = typename remove_all_extents<_Tp>::type;
1809 #endif
1810 
1811  // Pointer modifications.
1812 
1813  template<typename _Tp, typename>
1814  struct __remove_pointer_helper
1815  { typedef _Tp type; };
1816 
1817  template<typename _Tp, typename _Up>
1818  struct __remove_pointer_helper<_Tp, _Up*>
1819  { typedef _Up type; };
1820 
1821  /// remove_pointer
1822  template<typename _Tp>
1823  struct remove_pointer
1824  : public __remove_pointer_helper<_Tp, typename remove_cv<_Tp>::type>
1825  { };
1826 
1827  /// add_pointer
1828  template<typename _Tp, bool = __or_<__is_referenceable<_Tp>,
1829  is_void<_Tp>>::value>
1830  struct __add_pointer_helper
1831  { typedef _Tp type; };
1832 
1833  template<typename _Tp>
1834  struct __add_pointer_helper<_Tp, true>
1835  { typedef typename remove_reference<_Tp>::type* type; };
1836 
1837  template<typename _Tp>
1838  struct add_pointer
1839  : public __add_pointer_helper<_Tp>
1840  { };
1841 
1842 #if __cplusplus > 201103L
1843  /// Alias template for remove_pointer
1844  template<typename _Tp>
1845  using remove_pointer_t = typename remove_pointer<_Tp>::type;
1846 
1847  /// Alias template for add_pointer
1848  template<typename _Tp>
1849  using add_pointer_t = typename add_pointer<_Tp>::type;
1850 #endif
1851 
1852  template<std::size_t _Len>
1853  struct __aligned_storage_msa
1854  {
1855  union __type
1856  {
1857  unsigned char __data[_Len];
1858  struct __attribute__((__aligned__)) { } __align;
1859  };
1860  };
1861 
1862  /**
1863  * @brief Alignment type.
1864  *
1865  * The value of _Align is a default-alignment which shall be the
1866  * most stringent alignment requirement for any C++ object type
1867  * whose size is no greater than _Len (3.9). The member typedef
1868  * type shall be a POD type suitable for use as uninitialized
1869  * storage for any object whose size is at most _Len and whose
1870  * alignment is a divisor of _Align.
1871  */
1872  template<std::size_t _Len, std::size_t _Align =
1873  __alignof__(typename __aligned_storage_msa<_Len>::__type)>
1874  struct aligned_storage
1875  {
1876  union type
1877  {
1878  unsigned char __data[_Len];
1879  struct __attribute__((__aligned__((_Align)))) { } __align;
1880  };
1881  };
1882 
1883  template <typename... _Types>
1884  struct __strictest_alignment
1885  {
1886  static const size_t _S_alignment = 0;
1887  static const size_t _S_size = 0;
1888  };
1889 
1890  template <typename _Tp, typename... _Types>
1891  struct __strictest_alignment<_Tp, _Types...>
1892  {
1893  static const size_t _S_alignment =
1894  alignof(_Tp) > __strictest_alignment<_Types...>::_S_alignment
1895  ? alignof(_Tp) : __strictest_alignment<_Types...>::_S_alignment;
1896  static const size_t _S_size =
1897  sizeof(_Tp) > __strictest_alignment<_Types...>::_S_size
1898  ? sizeof(_Tp) : __strictest_alignment<_Types...>::_S_size;
1899  };
1900 
1901  /**
1902  * @brief Provide aligned storage for types.
1903  *
1904  * [meta.trans.other]
1905  *
1906  * Provides aligned storage for any of the provided types of at
1907  * least size _Len.
1908  *
1909  * @see aligned_storage
1910  */
1911  template <size_t _Len, typename... _Types>
1912  struct aligned_union
1913  {
1914  private:
1915  static_assert(sizeof...(_Types) != 0, "At least one type is required");
1916 
1917  using __strictest = __strictest_alignment<_Types...>;
1918  static const size_t _S_len = _Len > __strictest::_S_size
1919  ? _Len : __strictest::_S_size;
1920  public:
1921  /// The value of the strictest alignment of _Types.
1922  static const size_t alignment_value = __strictest::_S_alignment;
1923  /// The storage.
1924  typedef typename aligned_storage<_S_len, alignment_value>::type type;
1925  };
1926 
1927  template <size_t _Len, typename... _Types>
1928  const size_t aligned_union<_Len, _Types...>::alignment_value;
1929 
1930  // Decay trait for arrays and functions, used for perfect forwarding
1931  // in make_pair, make_tuple, etc.
1932  template<typename _Up,
1933  bool _IsArray = is_array<_Up>::value,
1934  bool _IsFunction = is_function<_Up>::value>
1935  struct __decay_selector;
1936 
1937  // NB: DR 705.
1938  template<typename _Up>
1939  struct __decay_selector<_Up, false, false>
1940  { typedef typename remove_cv<_Up>::type __type; };
1941 
1942  template<typename _Up>
1943  struct __decay_selector<_Up, true, false>
1944  { typedef typename remove_extent<_Up>::type* __type; };
1945 
1946  template<typename _Up>
1947  struct __decay_selector<_Up, false, true>
1948  { typedef typename add_pointer<_Up>::type __type; };
1949 
1950  /// decay
1951  template<typename _Tp>
1952  class decay
1953  {
1954  typedef typename remove_reference<_Tp>::type __remove_type;
1955 
1956  public:
1957  typedef typename __decay_selector<__remove_type>::__type type;
1958  };
1959 
1960  template<typename _Tp>
1961  class reference_wrapper;
1962 
1963  // Helper which adds a reference to a type when given a reference_wrapper
1964  template<typename _Tp>
1965  struct __strip_reference_wrapper
1966  {
1967  typedef _Tp __type;
1968  };
1969 
1970  template<typename _Tp>
1971  struct __strip_reference_wrapper<reference_wrapper<_Tp> >
1972  {
1973  typedef _Tp& __type;
1974  };
1975 
1976  template<typename _Tp>
1977  struct __decay_and_strip
1978  {
1979  typedef typename __strip_reference_wrapper<
1980  typename decay<_Tp>::type>::__type __type;
1981  };
1982 
1983 
1984  // Primary template.
1985  /// Define a member typedef @c type only if a boolean constant is true.
1986  template<bool, typename _Tp = void>
1987  struct enable_if
1988  { };
1989 
1990  // Partial specialization for true.
1991  template<typename _Tp>
1992  struct enable_if<true, _Tp>
1993  { typedef _Tp type; };
1994 
1995  template<typename... _Cond>
1996  using _Require = typename enable_if<__and_<_Cond...>::value>::type;
1997 
1998  // Primary template.
1999  /// Define a member typedef @c type to one of two argument types.
2000  template<bool _Cond, typename _Iftrue, typename _Iffalse>
2001  struct conditional
2002  { typedef _Iftrue type; };
2003 
2004  // Partial specialization for false.
2005  template<typename _Iftrue, typename _Iffalse>
2006  struct conditional<false, _Iftrue, _Iffalse>
2007  { typedef _Iffalse type; };
2008 
2009  /// common_type
2010  template<typename... _Tp>
2011  struct common_type;
2012 
2013  // Sfinae-friendly common_type implementation:
2014 
2015  struct __do_common_type_impl
2016  {
2017  template<typename _Tp, typename _Up>
2018  static __success_type<typename decay<decltype
2019  (true ? std::declval<_Tp>()
2020  : std::declval<_Up>())>::type> _S_test(int);
2021 
2022  template<typename, typename>
2023  static __failure_type _S_test(...);
2024  };
2025 
2026  template<typename _Tp, typename _Up>
2027  struct __common_type_impl
2028  : private __do_common_type_impl
2029  {
2030  typedef decltype(_S_test<_Tp, _Up>(0)) type;
2031  };
2032 
2033  struct __do_member_type_wrapper
2034  {
2035  template<typename _Tp>
2036  static __success_type<typename _Tp::type> _S_test(int);
2037 
2038  template<typename>
2039  static __failure_type _S_test(...);
2040  };
2041 
2042  template<typename _Tp>
2043  struct __member_type_wrapper
2044  : private __do_member_type_wrapper
2045  {
2046  typedef decltype(_S_test<_Tp>(0)) type;
2047  };
2048 
2049  template<typename _CTp, typename... _Args>
2050  struct __expanded_common_type_wrapper
2051  {
2052  typedef common_type<typename _CTp::type, _Args...> type;
2053  };
2054 
2055  template<typename... _Args>
2056  struct __expanded_common_type_wrapper<__failure_type, _Args...>
2057  { typedef __failure_type type; };
2058 
2059  template<typename _Tp>
2060  struct common_type<_Tp>
2061  { typedef typename decay<_Tp>::type type; };
2062 
2063  template<typename _Tp, typename _Up>
2064  struct common_type<_Tp, _Up>
2065  : public __common_type_impl<_Tp, _Up>::type
2066  { };
2067 
2068  template<typename _Tp, typename _Up, typename... _Vp>
2069  struct common_type<_Tp, _Up, _Vp...>
2070  : public __expanded_common_type_wrapper<typename __member_type_wrapper<
2071  common_type<_Tp, _Up>>::type, _Vp...>::type
2072  { };
2073 
2074  /// The underlying type of an enum.
2075  template<typename _Tp>
2076  struct underlying_type
2077  {
2078  typedef __underlying_type(_Tp) type;
2079  };
2080 
2081  template<typename _Tp>
2082  struct __declval_protector
2083  {
2084  static const bool __stop = false;
2085  };
2086 
2087  template<typename _Tp>
2088  auto declval() noexcept -> decltype(__declval<_Tp>(0))
2089  {
2090  static_assert(__declval_protector<_Tp>::__stop,
2091  "declval() must not be used!");
2092  return __declval<_Tp>(0);
2093  }
2094 
2095  /// result_of
2096  template<typename _Signature>
2097  class result_of;
2098 
2099  // Sfinae-friendly result_of implementation:
2100 
2101 #define __cpp_lib_result_of_sfinae 201210
2102 
2103  struct __invoke_memfun_ref { };
2104  struct __invoke_memfun_deref { };
2105  struct __invoke_memobj_ref { };
2106  struct __invoke_memobj_deref { };
2107  struct __invoke_other { };
2108 
2109  // Associate a tag type with a specialization of __success_type.
2110  template<typename _Tp, typename _Tag>
2111  struct __result_of_success : __success_type<_Tp>
2112  { using __invoke_type = _Tag; };
2113 
2114  // [func.require] paragraph 1 bullet 1:
2115  struct __result_of_memfun_ref_impl
2116  {
2117  template<typename _Fp, typename _Tp1, typename... _Args>
2118  static __result_of_success<decltype(
2119  (std::declval<_Tp1>().*std::declval<_Fp>())(std::declval<_Args>()...)
2120  ), __invoke_memfun_ref> _S_test(int);
2121 
2122  template<typename...>
2123  static __failure_type _S_test(...);
2124  };
2125 
2126  template<typename _MemPtr, typename _Arg, typename... _Args>
2127  struct __result_of_memfun_ref
2128  : private __result_of_memfun_ref_impl
2129  {
2130  typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
2131  };
2132 
2133  // [func.require] paragraph 1 bullet 2:
2134  struct __result_of_memfun_deref_impl
2135  {
2136  template<typename _Fp, typename _Tp1, typename... _Args>
2137  static __result_of_success<decltype(
2138  ((*std::declval<_Tp1>()).*std::declval<_Fp>())(std::declval<_Args>()...)
2139  ), __invoke_memfun_deref> _S_test(int);
2140 
2141  template<typename...>
2142  static __failure_type _S_test(...);
2143  };
2144 
2145  template<typename _MemPtr, typename _Arg, typename... _Args>
2146  struct __result_of_memfun_deref
2147  : private __result_of_memfun_deref_impl
2148  {
2149  typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
2150  };
2151 
2152  // [func.require] paragraph 1 bullet 3:
2153  struct __result_of_memobj_ref_impl
2154  {
2155  template<typename _Fp, typename _Tp1>
2156  static __result_of_success<decltype(
2157  std::declval<_Tp1>().*std::declval<_Fp>()
2158  ), __invoke_memobj_ref> _S_test(int);
2159 
2160  template<typename, typename>
2161  static __failure_type _S_test(...);
2162  };
2163 
2164  template<typename _MemPtr, typename _Arg>
2165  struct __result_of_memobj_ref
2166  : private __result_of_memobj_ref_impl
2167  {
2168  typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
2169  };
2170 
2171  // [func.require] paragraph 1 bullet 4:
2172  struct __result_of_memobj_deref_impl
2173  {
2174  template<typename _Fp, typename _Tp1>
2175  static __result_of_success<decltype(
2176  (*std::declval<_Tp1>()).*std::declval<_Fp>()
2177  ), __invoke_memobj_deref> _S_test(int);
2178 
2179  template<typename, typename>
2180  static __failure_type _S_test(...);
2181  };
2182 
2183  template<typename _MemPtr, typename _Arg>
2184  struct __result_of_memobj_deref
2185  : private __result_of_memobj_deref_impl
2186  {
2187  typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
2188  };
2189 
2190  template<typename _MemPtr, typename _Arg>
2191  struct __result_of_memobj;
2192 
2193  template<typename _Res, typename _Class, typename _Arg>
2194  struct __result_of_memobj<_Res _Class::*, _Arg>
2195  {
2196  typedef typename remove_cv<typename remove_reference<
2197  _Arg>::type>::type _Argval;
2198  typedef _Res _Class::* _MemPtr;
2199  typedef typename conditional<__or_<is_same<_Argval, _Class>,
2200  is_base_of<_Class, _Argval>>::value,
2201  __result_of_memobj_ref<_MemPtr, _Arg>,
2202  __result_of_memobj_deref<_MemPtr, _Arg>
2203  >::type::type type;
2204  };
2205 
2206  template<typename _MemPtr, typename _Arg, typename... _Args>
2207  struct __result_of_memfun;
2208 
2209  template<typename _Res, typename _Class, typename _Arg, typename... _Args>
2210  struct __result_of_memfun<_Res _Class::*, _Arg, _Args...>
2211  {
2212  typedef typename remove_cv<typename remove_reference<
2213  _Arg>::type>::type _Argval;
2214  typedef _Res _Class::* _MemPtr;
2215  typedef typename conditional<__or_<is_same<_Argval, _Class>,
2216  is_base_of<_Class, _Argval>>::value,
2217  __result_of_memfun_ref<_MemPtr, _Arg, _Args...>,
2218  __result_of_memfun_deref<_MemPtr, _Arg, _Args...>
2219  >::type::type type;
2220  };
2221 
2222  // _GLIBCXX_RESOLVE_LIB_DEFECTS
2223  // 2219. INVOKE-ing a pointer to member with a reference_wrapper
2224  // as the object expression
2225 
2226  // Used by result_of, invoke etc. to unwrap a reference_wrapper.
2227  template<typename _Tp, typename _Up = typename decay<_Tp>::type>
2228  struct __inv_unwrap
2229  {
2230  using type = _Tp;
2231  };
2232 
2233  template<typename _Tp, typename _Up>
2234  struct __inv_unwrap<_Tp, reference_wrapper<_Up>>
2235  {
2236  using type = _Up&;
2237  };
2238 
2239  template<bool, bool, typename _Functor, typename... _ArgTypes>
2240  struct __result_of_impl
2241  {
2242  typedef __failure_type type;
2243  };
2244 
2245  template<typename _MemPtr, typename _Arg>
2246  struct __result_of_impl<true, false, _MemPtr, _Arg>
2247  : public __result_of_memobj<typename decay<_MemPtr>::type,
2248  typename __inv_unwrap<_Arg>::type>
2249  { };
2250 
2251  template<typename _MemPtr, typename _Arg, typename... _Args>
2252  struct __result_of_impl<false, true, _MemPtr, _Arg, _Args...>
2253  : public __result_of_memfun<typename decay<_MemPtr>::type,
2254  typename __inv_unwrap<_Arg>::type, _Args...>
2255  { };
2256 
2257  // [func.require] paragraph 1 bullet 5:
2258  struct __result_of_other_impl
2259  {
2260  template<typename _Fn, typename... _Args>
2261  static __result_of_success<decltype(
2262  std::declval<_Fn>()(std::declval<_Args>()...)
2263  ), __invoke_other> _S_test(int);
2264 
2265  template<typename...>
2266  static __failure_type _S_test(...);
2267  };
2268 
2269  template<typename _Functor, typename... _ArgTypes>
2270  struct __result_of_impl<false, false, _Functor, _ArgTypes...>
2271  : private __result_of_other_impl
2272  {
2273  typedef decltype(_S_test<_Functor, _ArgTypes...>(0)) type;
2274  };
2275 
2276  // __invoke_result (std::invoke_result for C++11)
2277  template<typename _Functor, typename... _ArgTypes>
2278  struct __invoke_result
2279  : public __result_of_impl<
2280  is_member_object_pointer<
2281  typename remove_reference<_Functor>::type
2282  >::value,
2283  is_member_function_pointer<
2284  typename remove_reference<_Functor>::type
2285  >::value,
2286  _Functor, _ArgTypes...
2287  >::type
2288  { };
2289 
2290  template<typename _Functor, typename... _ArgTypes>
2291  struct result_of<_Functor(_ArgTypes...)>
2292  : public __invoke_result<_Functor, _ArgTypes...>
2293  { };
2294 
2295 #if __cplusplus > 201103L
2296  /// Alias template for aligned_storage
2297  template<size_t _Len, size_t _Align =
2298  __alignof__(typename __aligned_storage_msa<_Len>::__type)>
2299  using aligned_storage_t = typename aligned_storage<_Len, _Align>::type;
2300 
2301  template <size_t _Len, typename... _Types>
2302  using aligned_union_t = typename aligned_union<_Len, _Types...>::type;
2303 
2304  /// Alias template for decay
2305  template<typename _Tp>
2306  using decay_t = typename decay<_Tp>::type;
2307 
2308  /// Alias template for enable_if
2309  template<bool _Cond, typename _Tp = void>
2310  using enable_if_t = typename enable_if<_Cond, _Tp>::type;
2311 
2312  /// Alias template for conditional
2313  template<bool _Cond, typename _Iftrue, typename _Iffalse>
2314  using conditional_t = typename conditional<_Cond, _Iftrue, _Iffalse>::type;
2315 
2316  /// Alias template for common_type
2317  template<typename... _Tp>
2318  using common_type_t = typename common_type<_Tp...>::type;
2319 
2320  /// Alias template for underlying_type
2321  template<typename _Tp>
2322  using underlying_type_t = typename underlying_type<_Tp>::type;
2323 
2324  /// Alias template for result_of
2325  template<typename _Tp>
2326  using result_of_t = typename result_of<_Tp>::type;
2327 #endif
2328 
2329  template<typename...> using __void_t = void;
2330 
2331 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
2332 #define __cpp_lib_void_t 201411
2333  /// A metafunction that always yields void, used for detecting valid types.
2334  template<typename...> using void_t = void;
2335 #endif
2336 
2337  /// Implementation of the detection idiom (negative case).
2338  template<typename _Default, typename _AlwaysVoid,
2339  template<typename...> class _Op, typename... _Args>
2340  struct __detector
2341  {
2342  using value_t = false_type;
2343  using type = _Default;
2344  };
2345 
2346  /// Implementation of the detection idiom (positive case).
2347  template<typename _Default, template<typename...> class _Op,
2348  typename... _Args>
2349  struct __detector<_Default, __void_t<_Op<_Args...>>, _Op, _Args...>
2350  {
2351  using value_t = true_type;
2352  using type = _Op<_Args...>;
2353  };
2354 
2355  // Detect whether _Op<_Args...> is a valid type, use _Default if not.
2356  template<typename _Default, template<typename...> class _Op,
2357  typename... _Args>
2358  using __detected_or = __detector<_Default, void, _Op, _Args...>;
2359 
2360  // _Op<_Args...> if that is a valid type, otherwise _Default.
2361  template<typename _Default, template<typename...> class _Op,
2362  typename... _Args>
2363  using __detected_or_t
2364  = typename __detected_or<_Default, _Op, _Args...>::type;
2365 
2366  /// @} group metaprogramming
2367 
2368  /**
2369  * Use SFINAE to determine if the type _Tp has a publicly-accessible
2370  * member type _NTYPE.
2371  */
2372 #define _GLIBCXX_HAS_NESTED_TYPE(_NTYPE) \
2373  template<typename _Tp, typename = __void_t<>> \
2374  struct __has_##_NTYPE \
2375  : false_type \
2376  { }; \
2377  template<typename _Tp> \
2378  struct __has_##_NTYPE<_Tp, __void_t<typename _Tp::_NTYPE>> \
2379  : true_type \
2380  { };
2381 
2382  template <typename _Tp>
2383  struct __is_swappable;
2384 
2385  template <typename _Tp>
2386  struct __is_nothrow_swappable;
2387 
2388  template<typename... _Elements>
2389  class tuple;
2390 
2391  template<typename>
2392  struct __is_tuple_like_impl : false_type
2393  { };
2394 
2395  template<typename... _Tps>
2396  struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
2397  { };
2398 
2399  // Internal type trait that allows us to sfinae-protect tuple_cat.
2400  template<typename _Tp>
2401  struct __is_tuple_like
2402  : public __is_tuple_like_impl<typename remove_cv<
2403  typename remove_reference<_Tp>::type>::type>::type
2404  { };
2405 
2406  template<typename _Tp>
2407  inline
2408  typename enable_if<__and_<__not_<__is_tuple_like<_Tp>>,
2409  is_move_constructible<_Tp>,
2410  is_move_assignable<_Tp>>::value>::type
2411  swap(_Tp&, _Tp&)
2412  noexcept(__and_<is_nothrow_move_constructible<_Tp>,
2413  is_nothrow_move_assignable<_Tp>>::value);
2414 
2415  template<typename _Tp, size_t _Nm>
2416  inline
2417  typename enable_if<__is_swappable<_Tp>::value>::type
2418  swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
2419  noexcept(__is_nothrow_swappable<_Tp>::value);
2420 
2421  namespace __swappable_details {
2422  using std::swap;
2423 
2424  struct __do_is_swappable_impl
2425  {
2426  template<typename _Tp, typename
2427  = decltype(swap(std::declval<_Tp&>(), std::declval<_Tp&>()))>
2428  static true_type __test(int);
2429 
2430  template<typename>
2431  static false_type __test(...);
2432  };
2433 
2434  struct __do_is_nothrow_swappable_impl
2435  {
2436  template<typename _Tp>
2437  static __bool_constant<
2438  noexcept(swap(std::declval<_Tp&>(), std::declval<_Tp&>()))
2439  > __test(int);
2440 
2441  template<typename>
2442  static false_type __test(...);
2443  };
2444 
2445  } // namespace __swappable_details
2446 
2447  template<typename _Tp>
2448  struct __is_swappable_impl
2449  : public __swappable_details::__do_is_swappable_impl
2450  {
2451  typedef decltype(__test<_Tp>(0)) type;
2452  };
2453 
2454  template<typename _Tp>
2455  struct __is_nothrow_swappable_impl
2456  : public __swappable_details::__do_is_nothrow_swappable_impl
2457  {
2458  typedef decltype(__test<_Tp>(0)) type;
2459  };
2460 
2461  template<typename _Tp>
2462  struct __is_swappable
2463  : public __is_swappable_impl<_Tp>::type
2464  { };
2465 
2466  template<typename _Tp>
2467  struct __is_nothrow_swappable
2468  : public __is_nothrow_swappable_impl<_Tp>::type
2469  { };
2470 
2471 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
2472 #define __cpp_lib_is_swappable 201603
2473  /// Metafunctions used for detecting swappable types: p0185r1
2474 
2475  /// is_swappable
2476  template<typename _Tp>
2477  struct is_swappable
2478  : public __is_swappable_impl<_Tp>::type
2479  { };
2480 
2481  /// is_nothrow_swappable
2482  template<typename _Tp>
2483  struct is_nothrow_swappable
2484  : public __is_nothrow_swappable_impl<_Tp>::type
2485  { };
2486 
2487 #if __cplusplus >= 201402L
2488  /// is_swappable_v
2489  template<typename _Tp>
2490  _GLIBCXX17_INLINE constexpr bool is_swappable_v =
2491  is_swappable<_Tp>::value;
2492 
2493  /// is_nothrow_swappable_v
2494  template<typename _Tp>
2495  _GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_v =
2496  is_nothrow_swappable<_Tp>::value;
2497 #endif // __cplusplus >= 201402L
2498 
2499  namespace __swappable_with_details {
2500  using std::swap;
2501 
2502  struct __do_is_swappable_with_impl
2503  {
2504  template<typename _Tp, typename _Up, typename
2505  = decltype(swap(std::declval<_Tp>(), std::declval<_Up>())),
2506  typename
2507  = decltype(swap(std::declval<_Up>(), std::declval<_Tp>()))>
2508  static true_type __test(int);
2509 
2510  template<typename, typename>
2511  static false_type __test(...);
2512  };
2513 
2514  struct __do_is_nothrow_swappable_with_impl
2515  {
2516  template<typename _Tp, typename _Up>
2517  static __bool_constant<
2518  noexcept(swap(std::declval<_Tp>(), std::declval<_Up>()))
2519  &&
2520  noexcept(swap(std::declval<_Up>(), std::declval<_Tp>()))
2521  > __test(int);
2522 
2523  template<typename, typename>
2524  static false_type __test(...);
2525  };
2526 
2527  } // namespace __swappable_with_details
2528 
2529  template<typename _Tp, typename _Up>
2530  struct __is_swappable_with_impl
2531  : public __swappable_with_details::__do_is_swappable_with_impl
2532  {
2533  typedef decltype(__test<_Tp, _Up>(0)) type;
2534  };
2535 
2536  // Optimization for the homogenous lvalue case, not required:
2537  template<typename _Tp>
2538  struct __is_swappable_with_impl<_Tp&, _Tp&>
2539  : public __swappable_details::__do_is_swappable_impl
2540  {
2541  typedef decltype(__test<_Tp&>(0)) type;
2542  };
2543 
2544  template<typename _Tp, typename _Up>
2545  struct __is_nothrow_swappable_with_impl
2546  : public __swappable_with_details::__do_is_nothrow_swappable_with_impl
2547  {
2548  typedef decltype(__test<_Tp, _Up>(0)) type;
2549  };
2550 
2551  // Optimization for the homogenous lvalue case, not required:
2552  template<typename _Tp>
2553  struct __is_nothrow_swappable_with_impl<_Tp&, _Tp&>
2554  : public __swappable_details::__do_is_nothrow_swappable_impl
2555  {
2556  typedef decltype(__test<_Tp&>(0)) type;
2557  };
2558 
2559  /// is_swappable_with
2560  template<typename _Tp, typename _Up>
2561  struct is_swappable_with
2562  : public __is_swappable_with_impl<_Tp, _Up>::type
2563  { };
2564 
2565  /// is_nothrow_swappable_with
2566  template<typename _Tp, typename _Up>
2567  struct is_nothrow_swappable_with
2568  : public __is_nothrow_swappable_with_impl<_Tp, _Up>::type
2569  { };
2570 
2571 #if __cplusplus >= 201402L
2572  /// is_swappable_with_v
2573  template<typename _Tp, typename _Up>
2574  _GLIBCXX17_INLINE constexpr bool is_swappable_with_v =
2575  is_swappable_with<_Tp, _Up>::value;
2576 
2577  /// is_nothrow_swappable_with_v
2578  template<typename _Tp, typename _Up>
2579  _GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_with_v =
2580  is_nothrow_swappable_with<_Tp, _Up>::value;
2581 #endif // __cplusplus >= 201402L
2582 
2583 #endif// c++1z or gnu++11
2584 
2585  // __is_invocable (std::is_invocable for C++11)
2586 
2587  template<typename _Result, typename _Ret, typename = void>
2588  struct __is_invocable_impl : false_type { };
2589 
2590  template<typename _Result, typename _Ret>
2591  struct __is_invocable_impl<_Result, _Ret, __void_t<typename _Result::type>>
2592  : __or_<is_void<_Ret>, is_convertible<typename _Result::type, _Ret>>::type
2593  { };
2594 
2595  template<typename _Fn, typename... _ArgTypes>
2596  struct __is_invocable
2597  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>::type
2598  { };
2599 
2600  template<typename _Fn, typename _Tp, typename... _Args>
2601  constexpr bool __call_is_nt(__invoke_memfun_ref)
2602  {
2603  using _Up = typename __inv_unwrap<_Tp>::type;
2604  return noexcept((std::declval<_Up>().*std::declval<_Fn>())(
2605  std::declval<_Args>()...));
2606  }
2607 
2608  template<typename _Fn, typename _Tp, typename... _Args>
2609  constexpr bool __call_is_nt(__invoke_memfun_deref)
2610  {
2611  return noexcept(((*std::declval<_Tp>()).*std::declval<_Fn>())(
2612  std::declval<_Args>()...));
2613  }
2614 
2615  template<typename _Fn, typename _Tp>
2616  constexpr bool __call_is_nt(__invoke_memobj_ref)
2617  {
2618  using _Up = typename __inv_unwrap<_Tp>::type;
2619  return noexcept(std::declval<_Up>().*std::declval<_Fn>());
2620  }
2621 
2622  template<typename _Fn, typename _Tp>
2623  constexpr bool __call_is_nt(__invoke_memobj_deref)
2624  {
2625  return noexcept((*std::declval<_Tp>()).*std::declval<_Fn>());
2626  }
2627 
2628  template<typename _Fn, typename... _Args>
2629  constexpr bool __call_is_nt(__invoke_other)
2630  {
2631  return noexcept(std::declval<_Fn>()(std::declval<_Args>()...));
2632  }
2633 
2634  template<typename _Result, typename _Fn, typename... _Args>
2635  struct __call_is_nothrow
2636  : __bool_constant<
2637  std::__call_is_nt<_Fn, _Args...>(typename _Result::__invoke_type{})
2638  >
2639  { };
2640 
2641  template<typename _Fn, typename... _Args>
2642  using __call_is_nothrow_
2643  = __call_is_nothrow<__invoke_result<_Fn, _Args...>, _Fn, _Args...>;
2644 
2645  // __is_nothrow_invocable (std::is_nothrow_invocable for C++11)
2646  template<typename _Fn, typename... _Args>
2647  struct __is_nothrow_invocable
2648  : __and_<__is_invocable<_Fn, _Args...>,
2649  __call_is_nothrow_<_Fn, _Args...>>::type
2650  { };
2651 
2652  struct __nonesuch {
2653  __nonesuch() = delete;
2654  ~__nonesuch() = delete;
2655  __nonesuch(__nonesuch const&) = delete;
2656  void operator=(__nonesuch const&) = delete;
2657  };
2658 
2659 #if __cplusplus >= 201703L
2660 # define __cpp_lib_is_invocable 201703
2661 
2662  /// std::invoke_result
2663  template<typename _Functor, typename... _ArgTypes>
2664  struct invoke_result
2665  : public __invoke_result<_Functor, _ArgTypes...>
2666  { };
2667 
2668  /// std::invoke_result_t
2669  template<typename _Fn, typename... _Args>
2670  using invoke_result_t = typename invoke_result<_Fn, _Args...>::type;
2671 
2672  /// std::is_invocable
2673  template<typename _Fn, typename... _ArgTypes>
2674  struct is_invocable
2675  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>::type
2676  { };
2677 
2678  /// std::is_invocable_r
2679  template<typename _Ret, typename _Fn, typename... _ArgTypes>
2680  struct is_invocable_r
2681  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, _Ret>::type
2682  { };
2683 
2684  /// std::is_nothrow_invocable
2685  template<typename _Fn, typename... _ArgTypes>
2686  struct is_nothrow_invocable
2687  : __and_<__is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>,
2688  __call_is_nothrow_<_Fn, _ArgTypes...>>::type
2689  { };
2690 
2691  template<typename _Result, typename _Ret, typename = void>
2692  struct __is_nt_invocable_impl : false_type { };
2693 
2694  template<typename _Result, typename _Ret>
2695  struct __is_nt_invocable_impl<_Result, _Ret,
2696  __void_t<typename _Result::type>>
2697  : __or_<is_void<_Ret>,
2698  __and_<is_convertible<typename _Result::type, _Ret>,
2699  is_nothrow_constructible<_Ret, typename _Result::type>>>
2700  { };
2701 
2702  /// std::is_nothrow_invocable_r
2703  template<typename _Ret, typename _Fn, typename... _ArgTypes>
2704  struct is_nothrow_invocable_r
2705  : __and_<__is_nt_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, _Ret>,
2706  __call_is_nothrow_<_Fn, _ArgTypes...>>::type
2707  { };
2708 
2709  /// std::is_invocable_v
2710  template<typename _Fn, typename... _Args>
2711  inline constexpr bool is_invocable_v = is_invocable<_Fn, _Args...>::value;
2712 
2713  /// std::is_nothrow_invocable_v
2714  template<typename _Fn, typename... _Args>
2715  inline constexpr bool is_nothrow_invocable_v
2716  = is_nothrow_invocable<_Fn, _Args...>::value;
2717 
2718  /// std::is_invocable_r_v
2719  template<typename _Fn, typename... _Args>
2720  inline constexpr bool is_invocable_r_v
2721  = is_invocable_r<_Fn, _Args...>::value;
2722 
2723  /// std::is_nothrow_invocable_r_v
2724  template<typename _Fn, typename... _Args>
2725  inline constexpr bool is_nothrow_invocable_r_v
2726  = is_nothrow_invocable_r<_Fn, _Args...>::value;
2727 #endif // C++17
2728 
2729 #if __cplusplus >= 201703L
2730 # define __cpp_lib_type_trait_variable_templates 201510L
2731 template <typename _Tp>
2732  inline constexpr bool is_void_v = is_void<_Tp>::value;
2733 template <typename _Tp>
2734  inline constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value;
2735 template <typename _Tp>
2736  inline constexpr bool is_integral_v = is_integral<_Tp>::value;
2737 template <typename _Tp>
2738  inline constexpr bool is_floating_point_v = is_floating_point<_Tp>::value;
2739 template <typename _Tp>
2740  inline constexpr bool is_array_v = is_array<_Tp>::value;
2741 template <typename _Tp>
2742  inline constexpr bool is_pointer_v = is_pointer<_Tp>::value;
2743 template <typename _Tp>
2744  inline constexpr bool is_lvalue_reference_v =
2745  is_lvalue_reference<_Tp>::value;
2746 template <typename _Tp>
2747  inline constexpr bool is_rvalue_reference_v =
2748  is_rvalue_reference<_Tp>::value;
2749 template <typename _Tp>
2750  inline constexpr bool is_member_object_pointer_v =
2751  is_member_object_pointer<_Tp>::value;
2752 template <typename _Tp>
2753  inline constexpr bool is_member_function_pointer_v =
2754  is_member_function_pointer<_Tp>::value;
2755 template <typename _Tp>
2756  inline constexpr bool is_enum_v = is_enum<_Tp>::value;
2757 template <typename _Tp>
2758  inline constexpr bool is_union_v = is_union<_Tp>::value;
2759 template <typename _Tp>
2760  inline constexpr bool is_class_v = is_class<_Tp>::value;
2761 template <typename _Tp>
2762  inline constexpr bool is_function_v = is_function<_Tp>::value;
2763 template <typename _Tp>
2764  inline constexpr bool is_reference_v = is_reference<_Tp>::value;
2765 template <typename _Tp>
2766  inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
2767 template <typename _Tp>
2768  inline constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
2769 template <typename _Tp>
2770  inline constexpr bool is_object_v = is_object<_Tp>::value;
2771 template <typename _Tp>
2772  inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
2773 template <typename _Tp>
2774  inline constexpr bool is_compound_v = is_compound<_Tp>::value;
2775 template <typename _Tp>
2776  inline constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
2777 template <typename _Tp>
2778  inline constexpr bool is_const_v = is_const<_Tp>::value;
2779 template <typename _Tp>
2780  inline constexpr bool is_volatile_v = is_volatile<_Tp>::value;
2781 template <typename _Tp>
2782  inline constexpr bool is_trivial_v = is_trivial<_Tp>::value;
2783 template <typename _Tp>
2784  inline constexpr bool is_trivially_copyable_v =
2785  is_trivially_copyable<_Tp>::value;
2786 template <typename _Tp>
2787  inline constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
2788 template <typename _Tp>
2789  inline constexpr bool is_pod_v = is_pod<_Tp>::value;
2790 template <typename _Tp>
2791  inline constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
2792 template <typename _Tp>
2793  inline constexpr bool is_empty_v = is_empty<_Tp>::value;
2794 template <typename _Tp>
2795  inline constexpr bool is_polymorphic_v = is_polymorphic<_Tp>::value;
2796 template <typename _Tp>
2797  inline constexpr bool is_abstract_v = is_abstract<_Tp>::value;
2798 template <typename _Tp>
2799  inline constexpr bool is_final_v = is_final<_Tp>::value;
2800 template <typename _Tp>
2801  inline constexpr bool is_signed_v = is_signed<_Tp>::value;
2802 template <typename _Tp>
2803  inline constexpr bool is_unsigned_v = is_unsigned<_Tp>::value;
2804 template <typename _Tp, typename... _Args>
2805  inline constexpr bool is_constructible_v =
2806  is_constructible<_Tp, _Args...>::value;
2807 template <typename _Tp>
2808  inline constexpr bool is_default_constructible_v =
2809  is_default_constructible<_Tp>::value;
2810 template <typename _Tp>
2811  inline constexpr bool is_copy_constructible_v =
2812  is_copy_constructible<_Tp>::value;
2813 template <typename _Tp>
2814  inline constexpr bool is_move_constructible_v =
2815  is_move_constructible<_Tp>::value;
2816 template <typename _Tp, typename _Up>
2817  inline constexpr bool is_assignable_v = is_assignable<_Tp, _Up>::value;
2818 template <typename _Tp>
2819  inline constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value;
2820 template <typename _Tp>
2821  inline constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value;
2822 template <typename _Tp>
2823  inline constexpr bool is_destructible_v = is_destructible<_Tp>::value;
2824 template <typename _Tp, typename... _Args>
2825  inline constexpr bool is_trivially_constructible_v =
2826  is_trivially_constructible<_Tp, _Args...>::value;
2827 template <typename _Tp>
2828  inline constexpr bool is_trivially_default_constructible_v =
2829  is_trivially_default_constructible<_Tp>::value;
2830 template <typename _Tp>
2831  inline constexpr bool is_trivially_copy_constructible_v =
2832  is_trivially_copy_constructible<_Tp>::value;
2833 template <typename _Tp>
2834  inline constexpr bool is_trivially_move_constructible_v =
2835  is_trivially_move_constructible<_Tp>::value;
2836 template <typename _Tp, typename _Up>
2837  inline constexpr bool is_trivially_assignable_v =
2838  is_trivially_assignable<_Tp, _Up>::value;
2839 template <typename _Tp>
2840  inline constexpr bool is_trivially_copy_assignable_v =
2841  is_trivially_copy_assignable<_Tp>::value;
2842 template <typename _Tp>
2843  inline constexpr bool is_trivially_move_assignable_v =
2844  is_trivially_move_assignable<_Tp>::value;
2845 template <typename _Tp>
2846  inline constexpr bool is_trivially_destructible_v =
2847  is_trivially_destructible<_Tp>::value;
2848 template <typename _Tp, typename... _Args>
2849  inline constexpr bool is_nothrow_constructible_v =
2850  is_nothrow_constructible<_Tp, _Args...>::value;
2851 template <typename _Tp>
2852  inline constexpr bool is_nothrow_default_constructible_v =
2853  is_nothrow_default_constructible<_Tp>::value;
2854 template <typename _Tp>
2855  inline constexpr bool is_nothrow_copy_constructible_v =
2856  is_nothrow_copy_constructible<_Tp>::value;
2857 template <typename _Tp>
2858  inline constexpr bool is_nothrow_move_constructible_v =
2859  is_nothrow_move_constructible<_Tp>::value;
2860 template <typename _Tp, typename _Up>
2861  inline constexpr bool is_nothrow_assignable_v =
2862  is_nothrow_assignable<_Tp, _Up>::value;
2863 template <typename _Tp>
2864  inline constexpr bool is_nothrow_copy_assignable_v =
2865  is_nothrow_copy_assignable<_Tp>::value;
2866 template <typename _Tp>
2867  inline constexpr bool is_nothrow_move_assignable_v =
2868  is_nothrow_move_assignable<_Tp>::value;
2869 template <typename _Tp>
2870  inline constexpr bool is_nothrow_destructible_v =
2871  is_nothrow_destructible<_Tp>::value;
2872 template <typename _Tp>
2873  inline constexpr bool has_virtual_destructor_v =
2874  has_virtual_destructor<_Tp>::value;
2875 template <typename _Tp>
2876  inline constexpr size_t alignment_of_v = alignment_of<_Tp>::value;
2877 template <typename _Tp>
2878  inline constexpr size_t rank_v = rank<_Tp>::value;
2879 template <typename _Tp, unsigned _Idx = 0>
2880  inline constexpr size_t extent_v = extent<_Tp, _Idx>::value;
2881 template <typename _Tp, typename _Up>
2882  inline constexpr bool is_same_v = is_same<_Tp, _Up>::value;
2883 template <typename _Base, typename _Derived>
2884  inline constexpr bool is_base_of_v = is_base_of<_Base, _Derived>::value;
2885 template <typename _From, typename _To>
2886  inline constexpr bool is_convertible_v = is_convertible<_From, _To>::value;
2887 
2888 #if __GNUC__ >= 7
2889 # define _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP 1
2890 #elif defined(__is_identifier)
2891 // For non-GNU compilers:
2892 # if ! __is_identifier(__has_unique_object_representations)
2893 # define _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP 1
2894 # endif
2895 #endif
2896 
2897 #ifdef _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP
2898 # define __cpp_lib_has_unique_object_representations 201606
2899  /// has_unique_object_representations
2900  template<typename _Tp>
2901  struct has_unique_object_representations
2902  : bool_constant<__has_unique_object_representations(
2903  remove_cv_t<remove_all_extents_t<_Tp>>
2904  )>
2905  { };
2906 
2907  template<typename _Tp>
2908  inline constexpr bool has_unique_object_representations_v
2909  = has_unique_object_representations<_Tp>::value;
2910 #endif
2911 #undef _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP
2912 
2913 #if __GNUC__ >= 7
2914 # define _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE 1
2915 #elif defined(__is_identifier)
2916 // For non-GNU compilers:
2917 # if ! __is_identifier(__is_aggregate)
2918 # define _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE 1
2919 # endif
2920 #endif
2921 
2922 #ifdef _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE
2923 #define __cpp_lib_is_aggregate 201703
2924  /// is_aggregate
2925  template<typename _Tp>
2926  struct is_aggregate
2927  : bool_constant<__is_aggregate(remove_cv_t<_Tp>)> { };
2928 
2929  /// is_aggregate_v
2930  template<typename _Tp>
2931  inline constexpr bool is_aggregate_v = is_aggregate<_Tp>::value;
2932 #endif
2933 #undef _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE
2934 
2935 #endif // C++17
2936 
2937 #if __cplusplus > 201703L
2938  /// Byte order
2939  enum class endian
2940  {
2941  little = __ORDER_LITTLE_ENDIAN__,
2942  big = __ORDER_BIG_ENDIAN__,
2943  native = __BYTE_ORDER__
2944  };
2945 #endif // C++2a
2946 
2947 _GLIBCXX_END_NAMESPACE_VERSION
2948 } // namespace std
2949 
2950 #endif // C++11
2951 
2952 #endif // _GLIBCXX_TYPE_TRAITS