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 namespace std _GLIBCXX_VISIBILITY(default)
41 {
42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 
44  /**
45  * @defgroup metaprogramming Metaprogramming
46  * @ingroup utilities
47  *
48  * Template utilities for compile-time introspection and modification,
49  * including type classification traits, type property inspection traits
50  * and type transformation traits.
51  *
52  * @{
53  */
54 
55  /// integral_constant
56  template<typename _Tp, _Tp __v>
57  struct integral_constant
58  {
59  static constexpr _Tp value = __v;
60  typedef _Tp value_type;
61  typedef integral_constant<_Tp, __v> type;
62  constexpr operator value_type() const noexcept { return value; }
63 #if __cplusplus > 201103L
64 
65 #define __cpp_lib_integral_constant_callable 201304
66 
67  constexpr value_type operator()() const noexcept { return value; }
68 #endif
69  };
70 
71  template<typename _Tp, _Tp __v>
72  constexpr _Tp integral_constant<_Tp, __v>::value;
73 
74  /// The type used as a compile-time boolean with true value.
75  typedef integral_constant<bool, true> true_type;
76 
77  /// The type used as a compile-time boolean with false value.
78  typedef integral_constant<bool, false> false_type;
79 
80  template<bool __v>
81  using __bool_constant = integral_constant<bool, __v>;
82 
83 #if __cplusplus > 201402L
84 # define __cpp_lib_bool_constant 201505
85  template<bool __v>
86  using bool_constant = integral_constant<bool, __v>;
87 #endif
88 
89  // Meta programming helper types.
90 
91  template<bool, typename, typename>
92  struct conditional;
93 
94  template<typename...>
95  struct __or_;
96 
97  template<>
98  struct __or_<>
99  : public false_type
100  { };
101 
102  template<typename _B1>
103  struct __or_<_B1>
104  : public _B1
105  { };
106 
107  template<typename _B1, typename _B2>
108  struct __or_<_B1, _B2>
109  : public conditional<_B1::value, _B1, _B2>::type
110  { };
111 
112  template<typename _B1, typename _B2, typename _B3, typename... _Bn>
113  struct __or_<_B1, _B2, _B3, _Bn...>
114  : public conditional<_B1::value, _B1, __or_<_B2, _B3, _Bn...>>::type
115  { };
116 
117  template<typename...>
118  struct __and_;
119 
120  template<>
121  struct __and_<>
122  : public true_type
123  { };
124 
125  template<typename _B1>
126  struct __and_<_B1>
127  : public _B1
128  { };
129 
130  template<typename _B1, typename _B2>
131  struct __and_<_B1, _B2>
132  : public conditional<_B1::value, _B2, _B1>::type
133  { };
134 
135  template<typename _B1, typename _B2, typename _B3, typename... _Bn>
136  struct __and_<_B1, _B2, _B3, _Bn...>
137  : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
138  { };
139 
140  template<typename _Pp>
141  struct __not_
142  : public __bool_constant<!bool(_Pp::value)>
143  { };
144 
145 #if __cplusplus >= 201703L
146 
147 #define __cpp_lib_logical_traits 201510
148 
149  template<typename... _Bn>
150  struct conjunction
151  : __and_<_Bn...>
152  { };
153 
154  template<typename... _Bn>
155  struct disjunction
156  : __or_<_Bn...>
157  { };
158 
159  template<typename _Pp>
160  struct negation
161  : __not_<_Pp>
162  { };
163 
164  template<typename... _Bn>
165  inline constexpr bool conjunction_v = conjunction<_Bn...>::value;
166 
167  template<typename... _Bn>
168  inline constexpr bool disjunction_v = disjunction<_Bn...>::value;
169 
170  template<typename _Pp>
171  inline constexpr bool negation_v = negation<_Pp>::value;
172 
173 #endif // C++17
174 
175  // For several sfinae-friendly trait implementations we transport both the
176  // result information (as the member type) and the failure information (no
177  // member type). This is very similar to std::enable_if, but we cannot use
178  // them, because we need to derive from them as an implementation detail.
179 
180  template<typename _Tp>
181  struct __success_type
182  { typedef _Tp type; };
183 
184  struct __failure_type
185  { };
186 
187  // Primary type categories.
188 
189  template<typename>
190  struct remove_cv;
191 
192  template<typename>
193  struct __is_void_helper
194  : public false_type { };
195 
196  template<>
197  struct __is_void_helper<void>
198  : public true_type { };
199 
200  /// is_void
201  template<typename _Tp>
202  struct is_void
203  : public __is_void_helper<typename remove_cv<_Tp>::type>::type
204  { };
205 
206  template<typename>
207  struct __is_integral_helper
208  : public false_type { };
209 
210  template<>
211  struct __is_integral_helper<bool>
212  : public true_type { };
213 
214  template<>
215  struct __is_integral_helper<char>
216  : public true_type { };
217 
218  template<>
219  struct __is_integral_helper<signed char>
220  : public true_type { };
221 
222  template<>
223  struct __is_integral_helper<unsigned char>
224  : public true_type { };
225 
226 #ifdef _GLIBCXX_USE_WCHAR_T
227  template<>
228  struct __is_integral_helper<wchar_t>
229  : public true_type { };
230 #endif
231 
232  template<>
233  struct __is_integral_helper<char16_t>
234  : public true_type { };
235 
236  template<>
237  struct __is_integral_helper<char32_t>
238  : public true_type { };
239 
240  template<>
241  struct __is_integral_helper<short>
242  : public true_type { };
243 
244  template<>
245  struct __is_integral_helper<unsigned short>
246  : public true_type { };
247 
248  template<>
249  struct __is_integral_helper<int>
250  : public true_type { };
251 
252  template<>
253  struct __is_integral_helper<unsigned int>
254  : public true_type { };
255 
256  template<>
257  struct __is_integral_helper<long>
258  : public true_type { };
259 
260  template<>
261  struct __is_integral_helper<unsigned long>
262  : public true_type { };
263 
264  template<>
265  struct __is_integral_helper<long long>
266  : public true_type { };
267 
268  template<>
269  struct __is_integral_helper<unsigned long long>
270  : public true_type { };
271 
272  // Conditionalizing on __STRICT_ANSI__ here will break any port that
273  // uses one of these types for size_t.
274 #if defined(__GLIBCXX_TYPE_INT_N_0)
275  template<>
276  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_0>
277  : public true_type { };
278 
279  template<>
280  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_0>
281  : public true_type { };
282 #endif
283 #if defined(__GLIBCXX_TYPE_INT_N_1)
284  template<>
285  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_1>
286  : public true_type { };
287 
288  template<>
289  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_1>
290  : public true_type { };
291 #endif
292 #if defined(__GLIBCXX_TYPE_INT_N_2)
293  template<>
294  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_2>
295  : public true_type { };
296 
297  template<>
298  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_2>
299  : public true_type { };
300 #endif
301 #if defined(__GLIBCXX_TYPE_INT_N_3)
302  template<>
303  struct __is_integral_helper<__GLIBCXX_TYPE_INT_N_3>
304  : public true_type { };
305 
306  template<>
307  struct __is_integral_helper<unsigned __GLIBCXX_TYPE_INT_N_3>
308  : public true_type { };
309 #endif
310 
311  /// is_integral
312  template<typename _Tp>
313  struct is_integral
314  : public __is_integral_helper<typename remove_cv<_Tp>::type>::type
315  { };
316 
317  template<typename>
318  struct __is_floating_point_helper
319  : public false_type { };
320 
321  template<>
322  struct __is_floating_point_helper<float>
323  : public true_type { };
324 
325  template<>
326  struct __is_floating_point_helper<double>
327  : public true_type { };
328 
329  template<>
330  struct __is_floating_point_helper<long double>
331  : public true_type { };
332 
333 #if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
334  template<>
335  struct __is_floating_point_helper<__float128>
336  : public true_type { };
337 #endif
338 
339  /// is_floating_point
340  template<typename _Tp>
341  struct is_floating_point
342  : public __is_floating_point_helper<typename remove_cv<_Tp>::type>::type
343  { };
344 
345  /// is_array
346  template<typename>
347  struct is_array
348  : public false_type { };
349 
350  template<typename _Tp, std::size_t _Size>
351  struct is_array<_Tp[_Size]>
352  : public true_type { };
353 
354  template<typename _Tp>
355  struct is_array<_Tp[]>
356  : public true_type { };
357 
358  template<typename>
359  struct __is_pointer_helper
360  : public false_type { };
361 
362  template<typename _Tp>
363  struct __is_pointer_helper<_Tp*>
364  : public true_type { };
365 
366  /// is_pointer
367  template<typename _Tp>
368  struct is_pointer
369  : public __is_pointer_helper<typename remove_cv<_Tp>::type>::type
370  { };
371 
372  /// is_lvalue_reference
373  template<typename>
374  struct is_lvalue_reference
375  : public false_type { };
376 
377  template<typename _Tp>
378  struct is_lvalue_reference<_Tp&>
379  : public true_type { };
380 
381  /// is_rvalue_reference
382  template<typename>
383  struct is_rvalue_reference
384  : public false_type { };
385 
386  template<typename _Tp>
387  struct is_rvalue_reference<_Tp&&>
388  : public true_type { };
389 
390  template<typename>
391  struct is_function;
392 
393  template<typename>
394  struct __is_member_object_pointer_helper
395  : public false_type { };
396 
397  template<typename _Tp, typename _Cp>
398  struct __is_member_object_pointer_helper<_Tp _Cp::*>
399  : public integral_constant<bool, !is_function<_Tp>::value> { };
400 
401  /// is_member_object_pointer
402  template<typename _Tp>
403  struct is_member_object_pointer
404  : public __is_member_object_pointer_helper<
405  typename remove_cv<_Tp>::type>::type
406  { };
407 
408  template<typename>
409  struct __is_member_function_pointer_helper
410  : public false_type { };
411 
412  template<typename _Tp, typename _Cp>
413  struct __is_member_function_pointer_helper<_Tp _Cp::*>
414  : public integral_constant<bool, is_function<_Tp>::value> { };
415 
416  /// is_member_function_pointer
417  template<typename _Tp>
418  struct is_member_function_pointer
419  : public __is_member_function_pointer_helper<
420  typename remove_cv<_Tp>::type>::type
421  { };
422 
423  /// is_enum
424  template<typename _Tp>
425  struct is_enum
426  : public integral_constant<bool, __is_enum(_Tp)>
427  { };
428 
429  /// is_union
430  template<typename _Tp>
431  struct is_union
432  : public integral_constant<bool, __is_union(_Tp)>
433  { };
434 
435  /// is_class
436  template<typename _Tp>
437  struct is_class
438  : public integral_constant<bool, __is_class(_Tp)>
439  { };
440 
441  /// is_function
442  template<typename>
443  struct is_function
444  : public false_type { };
445 
446  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
447  struct is_function<_Res(_ArgTypes...) _GLIBCXX_NOEXCEPT_QUAL>
448  : public true_type { };
449 
450  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
451  struct is_function<_Res(_ArgTypes...) & _GLIBCXX_NOEXCEPT_QUAL>
452  : public true_type { };
453 
454  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
455  struct is_function<_Res(_ArgTypes...) && _GLIBCXX_NOEXCEPT_QUAL>
456  : public true_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...) const _GLIBCXX_NOEXCEPT_QUAL>
472  : public true_type { };
473 
474  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
475  struct is_function<_Res(_ArgTypes...) const & _GLIBCXX_NOEXCEPT_QUAL>
476  : public true_type { };
477 
478  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
479  struct is_function<_Res(_ArgTypes...) const && _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...) volatile _GLIBCXX_NOEXCEPT_QUAL>
496  : public true_type { };
497 
498  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
499  struct is_function<_Res(_ArgTypes...) volatile & _GLIBCXX_NOEXCEPT_QUAL>
500  : public true_type { };
501 
502  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
503  struct is_function<_Res(_ArgTypes...) volatile && _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...) const volatile _GLIBCXX_NOEXCEPT_QUAL>
520  : public true_type { };
521 
522  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
523  struct is_function<_Res(_ArgTypes...) const volatile & _GLIBCXX_NOEXCEPT_QUAL>
524  : public true_type { };
525 
526  template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
527  struct is_function<_Res(_ArgTypes...) const 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 #define __cpp_lib_is_null_pointer 201309
543 
544  template<typename>
545  struct __is_null_pointer_helper
546  : public false_type { };
547 
548  template<>
549  struct __is_null_pointer_helper<std::nullptr_t>
550  : public true_type { };
551 
552  /// is_null_pointer (LWG 2247).
553  template<typename _Tp>
554  struct is_null_pointer
555  : public __is_null_pointer_helper<typename remove_cv<_Tp>::type>::type
556  { };
557 
558  /// __is_nullptr_t (extension).
559  template<typename _Tp>
560  struct __is_nullptr_t
561  : public is_null_pointer<_Tp>
562  { };
563 
564  // Composite type categories.
565 
566  /// is_reference
567  template<typename _Tp>
568  struct is_reference
569  : public __or_<is_lvalue_reference<_Tp>,
570  is_rvalue_reference<_Tp>>::type
571  { };
572 
573  /// is_arithmetic
574  template<typename _Tp>
575  struct is_arithmetic
576  : public __or_<is_integral<_Tp>, is_floating_point<_Tp>>::type
577  { };
578 
579  /// is_fundamental
580  template<typename _Tp>
581  struct is_fundamental
582  : public __or_<is_arithmetic<_Tp>, is_void<_Tp>,
583  is_null_pointer<_Tp>>::type
584  { };
585 
586  /// is_object
587  template<typename _Tp>
588  struct is_object
589  : public __not_<__or_<is_function<_Tp>, is_reference<_Tp>,
590  is_void<_Tp>>>::type
591  { };
592 
593  template<typename>
594  struct is_member_pointer;
595 
596  /// is_scalar
597  template<typename _Tp>
598  struct is_scalar
599  : public __or_<is_arithmetic<_Tp>, is_enum<_Tp>, is_pointer<_Tp>,
600  is_member_pointer<_Tp>, is_null_pointer<_Tp>>::type
601  { };
602 
603  /// is_compound
604  template<typename _Tp>
605  struct is_compound
606  : public integral_constant<bool, !is_fundamental<_Tp>::value> { };
607 
608  template<typename _Tp>
609  struct __is_member_pointer_helper
610  : public false_type { };
611 
612  template<typename _Tp, typename _Cp>
613  struct __is_member_pointer_helper<_Tp _Cp::*>
614  : public true_type { };
615 
616  /// is_member_pointer
617  template<typename _Tp>
618  struct is_member_pointer
619  : public __is_member_pointer_helper<typename remove_cv<_Tp>::type>::type
620  { };
621 
622  // Utility to detect referenceable types ([defns.referenceable]).
623 
624  template<typename _Tp>
625  struct __is_referenceable
626  : public __or_<is_object<_Tp>, is_reference<_Tp>>::type
627  { };
628 
629  template<typename _Res, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
630  struct __is_referenceable<_Res(_Args...) _GLIBCXX_NOEXCEPT_QUAL>
631  : public true_type
632  { };
633 
634  template<typename _Res, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
635  struct __is_referenceable<_Res(_Args......) _GLIBCXX_NOEXCEPT_QUAL>
636  : public true_type
637  { };
638 
639  // Type properties.
640 
641  /// is_const
642  template<typename>
643  struct is_const
644  : public false_type { };
645 
646  template<typename _Tp>
647  struct is_const<_Tp const>
648  : public true_type { };
649 
650  /// is_volatile
651  template<typename>
652  struct is_volatile
653  : public false_type { };
654 
655  template<typename _Tp>
656  struct is_volatile<_Tp volatile>
657  : public true_type { };
658 
659  /// is_trivial
660  template<typename _Tp>
661  struct is_trivial
662  : public integral_constant<bool, __is_trivial(_Tp)>
663  { };
664 
665  // is_trivially_copyable
666  template<typename _Tp>
667  struct is_trivially_copyable
668  : public integral_constant<bool, __is_trivially_copyable(_Tp)>
669  { };
670 
671  /// is_standard_layout
672  template<typename _Tp>
673  struct is_standard_layout
674  : public integral_constant<bool, __is_standard_layout(_Tp)>
675  { };
676 
677  /// is_pod
678  // Could use is_standard_layout && is_trivial instead of the builtin.
679  template<typename _Tp>
680  struct is_pod
681  : public integral_constant<bool, __is_pod(_Tp)>
682  { };
683 
684  /// is_literal_type
685  template<typename _Tp>
686  struct is_literal_type
687  : public integral_constant<bool, __is_literal_type(_Tp)>
688  { };
689 
690  /// is_empty
691  template<typename _Tp>
692  struct is_empty
693  : public integral_constant<bool, __is_empty(_Tp)>
694  { };
695 
696  /// is_polymorphic
697  template<typename _Tp>
698  struct is_polymorphic
699  : public integral_constant<bool, __is_polymorphic(_Tp)>
700  { };
701 
702 #if __cplusplus >= 201402L
703 #define __cpp_lib_is_final 201402L
704  /// is_final
705  template<typename _Tp>
706  struct is_final
707  : public integral_constant<bool, __is_final(_Tp)>
708  { };
709 #endif
710 
711  /// is_abstract
712  template<typename _Tp>
713  struct is_abstract
714  : public integral_constant<bool, __is_abstract(_Tp)>
715  { };
716 
717  template<typename _Tp,
718  bool = is_arithmetic<_Tp>::value>
719  struct __is_signed_helper
720  : public false_type { };
721 
722  template<typename _Tp>
723  struct __is_signed_helper<_Tp, true>
724  : public integral_constant<bool, _Tp(-1) < _Tp(0)>
725  { };
726 
727  /// is_signed
728  template<typename _Tp>
729  struct is_signed
730  : public __is_signed_helper<_Tp>::type
731  { };
732 
733  /// is_unsigned
734  template<typename _Tp>
735  struct is_unsigned
736  : public __and_<is_arithmetic<_Tp>, __not_<is_signed<_Tp>>>
737  { };
738 
739 
740  // Destructible and constructible type properties.
741 
742  /**
743  * @brief Utility to simplify expressions used in unevaluated operands
744  * @ingroup utilities
745  */
746 
747  template<typename _Tp, typename _Up = _Tp&&>
748  _Up
749  __declval(int);
750 
751  template<typename _Tp>
752  _Tp
753  __declval(long);
754 
755  template<typename _Tp>
756  auto declval() noexcept -> decltype(__declval<_Tp>(0));
757 
758  template<typename, unsigned = 0>
759  struct extent;
760 
761  template<typename>
762  struct remove_all_extents;
763 
764  template<typename _Tp>
765  struct __is_array_known_bounds
766  : public integral_constant<bool, (extent<_Tp>::value > 0)>
767  { };
768 
769  template<typename _Tp>
770  struct __is_array_unknown_bounds
771  : public __and_<is_array<_Tp>, __not_<extent<_Tp>>>
772  { };
773 
774  // In N3290 is_destructible does not say anything about function
775  // types and abstract types, see LWG 2049. This implementation
776  // describes function types as non-destructible and all complete
777  // object types as destructible, iff the explicit destructor
778  // call expression is wellformed.
779  struct __do_is_destructible_impl
780  {
781  template<typename _Tp, typename = decltype(declval<_Tp&>().~_Tp())>
782  static true_type __test(int);
783 
784  template<typename>
785  static false_type __test(...);
786  };
787 
788  template<typename _Tp>
789  struct __is_destructible_impl
790  : public __do_is_destructible_impl
791  {
792  typedef decltype(__test<_Tp>(0)) type;
793  };
794 
795  template<typename _Tp,
796  bool = __or_<is_void<_Tp>,
797  __is_array_unknown_bounds<_Tp>,
798  is_function<_Tp>>::value,
799  bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
800  struct __is_destructible_safe;
801 
802  template<typename _Tp>
803  struct __is_destructible_safe<_Tp, false, false>
804  : public __is_destructible_impl<typename
805  remove_all_extents<_Tp>::type>::type
806  { };
807 
808  template<typename _Tp>
809  struct __is_destructible_safe<_Tp, true, false>
810  : public false_type { };
811 
812  template<typename _Tp>
813  struct __is_destructible_safe<_Tp, false, true>
814  : public true_type { };
815 
816  /// is_destructible
817  template<typename _Tp>
818  struct is_destructible
819  : public __is_destructible_safe<_Tp>::type
820  { };
821 
822  // is_nothrow_destructible requires that is_destructible is
823  // satisfied as well. We realize that by mimicing the
824  // implementation of is_destructible but refer to noexcept(expr)
825  // instead of decltype(expr).
826  struct __do_is_nt_destructible_impl
827  {
828  template<typename _Tp>
829  static integral_constant<bool, noexcept(declval<_Tp&>().~_Tp())>
830  __test(int);
831 
832  template<typename>
833  static false_type __test(...);
834  };
835 
836  template<typename _Tp>
837  struct __is_nt_destructible_impl
838  : public __do_is_nt_destructible_impl
839  {
840  typedef decltype(__test<_Tp>(0)) type;
841  };
842 
843  template<typename _Tp,
844  bool = __or_<is_void<_Tp>,
845  __is_array_unknown_bounds<_Tp>,
846  is_function<_Tp>>::value,
847  bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
848  struct __is_nt_destructible_safe;
849 
850  template<typename _Tp>
851  struct __is_nt_destructible_safe<_Tp, false, false>
852  : public __is_nt_destructible_impl<typename
853  remove_all_extents<_Tp>::type>::type
854  { };
855 
856  template<typename _Tp>
857  struct __is_nt_destructible_safe<_Tp, true, false>
858  : public false_type { };
859 
860  template<typename _Tp>
861  struct __is_nt_destructible_safe<_Tp, false, true>
862  : public true_type { };
863 
864  /// is_nothrow_destructible
865  template<typename _Tp>
866  struct is_nothrow_destructible
867  : public __is_nt_destructible_safe<_Tp>::type
868  { };
869 
870  struct __do_is_default_constructible_impl
871  {
872  template<typename _Tp, typename = decltype(_Tp())>
873  static true_type __test(int);
874 
875  template<typename>
876  static false_type __test(...);
877  };
878 
879  template<typename _Tp>
880  struct __is_default_constructible_impl
881  : public __do_is_default_constructible_impl
882  {
883  typedef decltype(__test<_Tp>(0)) type;
884  };
885 
886  template<typename _Tp>
887  struct __is_default_constructible_atom
888  : public __and_<__not_<is_void<_Tp>>,
889  __is_default_constructible_impl<_Tp>>
890  { };
891 
892  template<typename _Tp, bool = is_array<_Tp>::value>
893  struct __is_default_constructible_safe;
894 
895  // The following technique is a workaround for a current core language
896  // restriction, which does not allow for array types to occur in
897  // functional casts of the form T(). Complete arrays can be default-
898  // constructed, if the element type is default-constructible, but
899  // arrays with unknown bounds are not.
900  template<typename _Tp>
901  struct __is_default_constructible_safe<_Tp, true>
902  : public __and_<__is_array_known_bounds<_Tp>,
903  __is_default_constructible_atom<typename
904  remove_all_extents<_Tp>::type>>
905  { };
906 
907  template<typename _Tp>
908  struct __is_default_constructible_safe<_Tp, false>
909  : public __is_default_constructible_atom<_Tp>::type
910  { };
911 
912  /// is_default_constructible
913  template<typename _Tp>
914  struct is_default_constructible
915  : public __is_default_constructible_safe<_Tp>::type
916  { };
917 
918  /// is_constructible
919  template<typename _Tp, typename... _Args>
920  struct is_constructible
921  : public __bool_constant<__is_constructible(_Tp, _Args...)>
922  { };
923 
924  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
925  struct __is_copy_constructible_impl;
926 
927  template<typename _Tp>
928  struct __is_copy_constructible_impl<_Tp, false>
929  : public false_type { };
930 
931  template<typename _Tp>
932  struct __is_copy_constructible_impl<_Tp, true>
933  : public is_constructible<_Tp, const _Tp&>
934  { };
935 
936  /// is_copy_constructible
937  template<typename _Tp>
938  struct is_copy_constructible
939  : public __is_copy_constructible_impl<_Tp>
940  { };
941 
942  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
943  struct __is_move_constructible_impl;
944 
945  template<typename _Tp>
946  struct __is_move_constructible_impl<_Tp, false>
947  : public false_type { };
948 
949  template<typename _Tp>
950  struct __is_move_constructible_impl<_Tp, true>
951  : public is_constructible<_Tp, _Tp&&>
952  { };
953 
954  /// is_move_constructible
955  template<typename _Tp>
956  struct is_move_constructible
957  : public __is_move_constructible_impl<_Tp>
958  { };
959 
960  template<typename _Tp>
961  struct __is_nt_default_constructible_atom
962  : public integral_constant<bool, noexcept(_Tp())>
963  { };
964 
965  template<typename _Tp, bool = is_array<_Tp>::value>
966  struct __is_nt_default_constructible_impl;
967 
968  template<typename _Tp>
969  struct __is_nt_default_constructible_impl<_Tp, true>
970  : public __and_<__is_array_known_bounds<_Tp>,
971  __is_nt_default_constructible_atom<typename
972  remove_all_extents<_Tp>::type>>
973  { };
974 
975  template<typename _Tp>
976  struct __is_nt_default_constructible_impl<_Tp, false>
977  : public __is_nt_default_constructible_atom<_Tp>
978  { };
979 
980  /// is_nothrow_default_constructible
981  template<typename _Tp>
982  struct is_nothrow_default_constructible
983  : public __and_<is_default_constructible<_Tp>,
984  __is_nt_default_constructible_impl<_Tp>>
985  { };
986 
987  template<typename _Tp, typename... _Args>
988  struct __is_nt_constructible_impl
989  : public integral_constant<bool, noexcept(_Tp(declval<_Args>()...))>
990  { };
991 
992  template<typename _Tp, typename _Arg>
993  struct __is_nt_constructible_impl<_Tp, _Arg>
994  : public integral_constant<bool,
995  noexcept(static_cast<_Tp>(declval<_Arg>()))>
996  { };
997 
998  template<typename _Tp>
999  struct __is_nt_constructible_impl<_Tp>
1000  : public is_nothrow_default_constructible<_Tp>
1001  { };
1002 
1003  /// is_nothrow_constructible
1004  template<typename _Tp, typename... _Args>
1005  struct is_nothrow_constructible
1006  : public __and_<is_constructible<_Tp, _Args...>,
1007  __is_nt_constructible_impl<_Tp, _Args...>>
1008  { };
1009 
1010  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1011  struct __is_nothrow_copy_constructible_impl;
1012 
1013  template<typename _Tp>
1014  struct __is_nothrow_copy_constructible_impl<_Tp, false>
1015  : public false_type { };
1016 
1017  template<typename _Tp>
1018  struct __is_nothrow_copy_constructible_impl<_Tp, true>
1019  : public is_nothrow_constructible<_Tp, const _Tp&>
1020  { };
1021 
1022  /// is_nothrow_copy_constructible
1023  template<typename _Tp>
1024  struct is_nothrow_copy_constructible
1025  : public __is_nothrow_copy_constructible_impl<_Tp>
1026  { };
1027 
1028  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1029  struct __is_nothrow_move_constructible_impl;
1030 
1031  template<typename _Tp>
1032  struct __is_nothrow_move_constructible_impl<_Tp, false>
1033  : public false_type { };
1034 
1035  template<typename _Tp>
1036  struct __is_nothrow_move_constructible_impl<_Tp, true>
1037  : public is_nothrow_constructible<_Tp, _Tp&&>
1038  { };
1039 
1040  /// is_nothrow_move_constructible
1041  template<typename _Tp>
1042  struct is_nothrow_move_constructible
1043  : public __is_nothrow_move_constructible_impl<_Tp>
1044  { };
1045 
1046  /// is_assignable
1047  template<typename _Tp, typename _Up>
1048  struct is_assignable
1049  : public __bool_constant<__is_assignable(_Tp, _Up)>
1050  { };
1051 
1052  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1053  struct __is_copy_assignable_impl;
1054 
1055  template<typename _Tp>
1056  struct __is_copy_assignable_impl<_Tp, false>
1057  : public false_type { };
1058 
1059  template<typename _Tp>
1060  struct __is_copy_assignable_impl<_Tp, true>
1061  : public is_assignable<_Tp&, const _Tp&>
1062  { };
1063 
1064  /// is_copy_assignable
1065  template<typename _Tp>
1066  struct is_copy_assignable
1067  : public __is_copy_assignable_impl<_Tp>
1068  { };
1069 
1070  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1071  struct __is_move_assignable_impl;
1072 
1073  template<typename _Tp>
1074  struct __is_move_assignable_impl<_Tp, false>
1075  : public false_type { };
1076 
1077  template<typename _Tp>
1078  struct __is_move_assignable_impl<_Tp, true>
1079  : public is_assignable<_Tp&, _Tp&&>
1080  { };
1081 
1082  /// is_move_assignable
1083  template<typename _Tp>
1084  struct is_move_assignable
1085  : public __is_move_assignable_impl<_Tp>
1086  { };
1087 
1088  template<typename _Tp, typename _Up>
1089  struct __is_nt_assignable_impl
1090  : public integral_constant<bool, noexcept(declval<_Tp>() = declval<_Up>())>
1091  { };
1092 
1093  /// is_nothrow_assignable
1094  template<typename _Tp, typename _Up>
1095  struct is_nothrow_assignable
1096  : public __and_<is_assignable<_Tp, _Up>,
1097  __is_nt_assignable_impl<_Tp, _Up>>
1098  { };
1099 
1100  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1101  struct __is_nt_copy_assignable_impl;
1102 
1103  template<typename _Tp>
1104  struct __is_nt_copy_assignable_impl<_Tp, false>
1105  : public false_type { };
1106 
1107  template<typename _Tp>
1108  struct __is_nt_copy_assignable_impl<_Tp, true>
1109  : public is_nothrow_assignable<_Tp&, const _Tp&>
1110  { };
1111 
1112  /// is_nothrow_copy_assignable
1113  template<typename _Tp>
1114  struct is_nothrow_copy_assignable
1115  : public __is_nt_copy_assignable_impl<_Tp>
1116  { };
1117 
1118  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1119  struct __is_nt_move_assignable_impl;
1120 
1121  template<typename _Tp>
1122  struct __is_nt_move_assignable_impl<_Tp, false>
1123  : public false_type { };
1124 
1125  template<typename _Tp>
1126  struct __is_nt_move_assignable_impl<_Tp, true>
1127  : public is_nothrow_assignable<_Tp&, _Tp&&>
1128  { };
1129 
1130  /// is_nothrow_move_assignable
1131  template<typename _Tp>
1132  struct is_nothrow_move_assignable
1133  : public __is_nt_move_assignable_impl<_Tp>
1134  { };
1135 
1136  /// is_trivially_constructible
1137  template<typename _Tp, typename... _Args>
1138  struct is_trivially_constructible
1139  : public __and_<is_constructible<_Tp, _Args...>, __bool_constant<
1140  __is_trivially_constructible(_Tp, _Args...)>>::type
1141  { };
1142 
1143  /// is_trivially_default_constructible
1144  template<typename _Tp>
1145  struct is_trivially_default_constructible
1146  : public is_trivially_constructible<_Tp>::type
1147  { };
1148 
1149  struct __do_is_implicitly_default_constructible_impl
1150  {
1151  template <typename _Tp>
1152  static void __helper(const _Tp&);
1153 
1154  template <typename _Tp>
1155  static true_type __test(const _Tp&,
1156  decltype(__helper<const _Tp&>({}))* = 0);
1157 
1158  static false_type __test(...);
1159  };
1160 
1161  template<typename _Tp>
1162  struct __is_implicitly_default_constructible_impl
1163  : public __do_is_implicitly_default_constructible_impl
1164  {
1165  typedef decltype(__test(declval<_Tp>())) type;
1166  };
1167 
1168  template<typename _Tp>
1169  struct __is_implicitly_default_constructible_safe
1170  : public __is_implicitly_default_constructible_impl<_Tp>::type
1171  { };
1172 
1173  template <typename _Tp>
1174  struct __is_implicitly_default_constructible
1175  : public __and_<is_default_constructible<_Tp>,
1176  __is_implicitly_default_constructible_safe<_Tp>>
1177  { };
1178 
1179  /// is_trivially_copy_constructible
1180 
1181  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1182  struct __is_trivially_copy_constructible_impl;
1183 
1184  template<typename _Tp>
1185  struct __is_trivially_copy_constructible_impl<_Tp, false>
1186  : public false_type { };
1187 
1188  template<typename _Tp>
1189  struct __is_trivially_copy_constructible_impl<_Tp, true>
1190  : public __and_<is_copy_constructible<_Tp>,
1191  integral_constant<bool,
1192  __is_trivially_constructible(_Tp, const _Tp&)>>
1193  { };
1194 
1195  template<typename _Tp>
1196  struct is_trivially_copy_constructible
1197  : public __is_trivially_copy_constructible_impl<_Tp>
1198  { };
1199 
1200  /// is_trivially_move_constructible
1201 
1202  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1203  struct __is_trivially_move_constructible_impl;
1204 
1205  template<typename _Tp>
1206  struct __is_trivially_move_constructible_impl<_Tp, false>
1207  : public false_type { };
1208 
1209  template<typename _Tp>
1210  struct __is_trivially_move_constructible_impl<_Tp, true>
1211  : public __and_<is_move_constructible<_Tp>,
1212  integral_constant<bool,
1213  __is_trivially_constructible(_Tp, _Tp&&)>>
1214  { };
1215 
1216  template<typename _Tp>
1217  struct is_trivially_move_constructible
1218  : public __is_trivially_move_constructible_impl<_Tp>
1219  { };
1220 
1221  /// is_trivially_assignable
1222  template<typename _Tp, typename _Up>
1223  struct is_trivially_assignable
1224  : public __bool_constant<__is_trivially_assignable(_Tp, _Up)>
1225  { };
1226 
1227  /// is_trivially_copy_assignable
1228 
1229  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1230  struct __is_trivially_copy_assignable_impl;
1231 
1232  template<typename _Tp>
1233  struct __is_trivially_copy_assignable_impl<_Tp, false>
1234  : public false_type { };
1235 
1236  template<typename _Tp>
1237  struct __is_trivially_copy_assignable_impl<_Tp, true>
1238  : public __and_<is_copy_assignable<_Tp>,
1239  integral_constant<bool,
1240  __is_trivially_assignable(_Tp&, const _Tp&)>>
1241  { };
1242 
1243  template<typename _Tp>
1244  struct is_trivially_copy_assignable
1245  : public __is_trivially_copy_assignable_impl<_Tp>
1246  { };
1247 
1248  /// is_trivially_move_assignable
1249 
1250  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1251  struct __is_trivially_move_assignable_impl;
1252 
1253  template<typename _Tp>
1254  struct __is_trivially_move_assignable_impl<_Tp, false>
1255  : public false_type { };
1256 
1257  template<typename _Tp>
1258  struct __is_trivially_move_assignable_impl<_Tp, true>
1259  : public __and_<is_move_assignable<_Tp>,
1260  integral_constant<bool,
1261  __is_trivially_assignable(_Tp&, _Tp&&)>>
1262  { };
1263 
1264  template<typename _Tp>
1265  struct is_trivially_move_assignable
1266  : public __is_trivially_move_assignable_impl<_Tp>
1267  { };
1268 
1269  /// is_trivially_destructible
1270  template<typename _Tp>
1271  struct is_trivially_destructible
1272  : public __and_<is_destructible<_Tp>, integral_constant<bool,
1273  __has_trivial_destructor(_Tp)>>
1274  { };
1275 
1276 
1277  /// has_virtual_destructor
1278  template<typename _Tp>
1279  struct has_virtual_destructor
1280  : public integral_constant<bool, __has_virtual_destructor(_Tp)>
1281  { };
1282 
1283 
1284  // type property queries.
1285 
1286  /// alignment_of
1287  template<typename _Tp>
1288  struct alignment_of
1289  : public integral_constant<std::size_t, alignof(_Tp)> { };
1290 
1291  /// rank
1292  template<typename>
1293  struct rank
1294  : public integral_constant<std::size_t, 0> { };
1295 
1296  template<typename _Tp, std::size_t _Size>
1297  struct rank<_Tp[_Size]>
1298  : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
1299 
1300  template<typename _Tp>
1301  struct rank<_Tp[]>
1302  : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
1303 
1304  /// extent
1305  template<typename, unsigned _Uint>
1306  struct extent
1307  : public integral_constant<std::size_t, 0> { };
1308 
1309  template<typename _Tp, unsigned _Uint, std::size_t _Size>
1310  struct extent<_Tp[_Size], _Uint>
1311  : public integral_constant<std::size_t,
1312  _Uint == 0 ? _Size : extent<_Tp,
1313  _Uint - 1>::value>
1314  { };
1315 
1316  template<typename _Tp, unsigned _Uint>
1317  struct extent<_Tp[], _Uint>
1318  : public integral_constant<std::size_t,
1319  _Uint == 0 ? 0 : extent<_Tp,
1320  _Uint - 1>::value>
1321  { };
1322 
1323 
1324  // Type relations.
1325 
1326  /// is_same
1327  template<typename, typename>
1328  struct is_same
1329  : public false_type { };
1330 
1331  template<typename _Tp>
1332  struct is_same<_Tp, _Tp>
1333  : public true_type { };
1334 
1335  /// is_base_of
1336  template<typename _Base, typename _Derived>
1337  struct is_base_of
1338  : public integral_constant<bool, __is_base_of(_Base, _Derived)>
1339  { };
1340 
1341  template<typename _From, typename _To,
1342  bool = __or_<is_void<_From>, is_function<_To>,
1343  is_array<_To>>::value>
1344  struct __is_convertible_helper
1345  { typedef typename is_void<_To>::type type; };
1346 
1347  template<typename _From, typename _To>
1348  class __is_convertible_helper<_From, _To, false>
1349  {
1350  template<typename _To1>
1351  static void __test_aux(_To1);
1352 
1353  template<typename _From1, typename _To1,
1354  typename = decltype(__test_aux<_To1>(std::declval<_From1>()))>
1355  static true_type
1356  __test(int);
1357 
1358  template<typename, typename>
1359  static false_type
1360  __test(...);
1361 
1362  public:
1363  typedef decltype(__test<_From, _To>(0)) type;
1364  };
1365 
1366 
1367  /// is_convertible
1368  template<typename _From, typename _To>
1369  struct is_convertible
1370  : public __is_convertible_helper<_From, _To>::type
1371  { };
1372 
1373 
1374  // Const-volatile modifications.
1375 
1376  /// remove_const
1377  template<typename _Tp>
1378  struct remove_const
1379  { typedef _Tp type; };
1380 
1381  template<typename _Tp>
1382  struct remove_const<_Tp const>
1383  { typedef _Tp type; };
1384 
1385  /// remove_volatile
1386  template<typename _Tp>
1387  struct remove_volatile
1388  { typedef _Tp type; };
1389 
1390  template<typename _Tp>
1391  struct remove_volatile<_Tp volatile>
1392  { typedef _Tp type; };
1393 
1394  /// remove_cv
1395  template<typename _Tp>
1396  struct remove_cv
1397  {
1398  typedef typename
1399  remove_const<typename remove_volatile<_Tp>::type>::type type;
1400  };
1401 
1402  /// add_const
1403  template<typename _Tp>
1404  struct add_const
1405  { typedef _Tp const type; };
1406 
1407  /// add_volatile
1408  template<typename _Tp>
1409  struct add_volatile
1410  { typedef _Tp volatile type; };
1411 
1412  /// add_cv
1413  template<typename _Tp>
1414  struct add_cv
1415  {
1416  typedef typename
1417  add_const<typename add_volatile<_Tp>::type>::type type;
1418  };
1419 
1420 #if __cplusplus > 201103L
1421 
1422 #define __cpp_lib_transformation_trait_aliases 201304
1423 
1424  /// Alias template for remove_const
1425  template<typename _Tp>
1426  using remove_const_t = typename remove_const<_Tp>::type;
1427 
1428  /// Alias template for remove_volatile
1429  template<typename _Tp>
1430  using remove_volatile_t = typename remove_volatile<_Tp>::type;
1431 
1432  /// Alias template for remove_cv
1433  template<typename _Tp>
1434  using remove_cv_t = typename remove_cv<_Tp>::type;
1435 
1436  /// Alias template for add_const
1437  template<typename _Tp>
1438  using add_const_t = typename add_const<_Tp>::type;
1439 
1440  /// Alias template for add_volatile
1441  template<typename _Tp>
1442  using add_volatile_t = typename add_volatile<_Tp>::type;
1443 
1444  /// Alias template for add_cv
1445  template<typename _Tp>
1446  using add_cv_t = typename add_cv<_Tp>::type;
1447 #endif
1448 
1449  // Reference transformations.
1450 
1451  /// remove_reference
1452  template<typename _Tp>
1453  struct remove_reference
1454  { typedef _Tp type; };
1455 
1456  template<typename _Tp>
1457  struct remove_reference<_Tp&>
1458  { typedef _Tp type; };
1459 
1460  template<typename _Tp>
1461  struct remove_reference<_Tp&&>
1462  { typedef _Tp type; };
1463 
1464  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1465  struct __add_lvalue_reference_helper
1466  { typedef _Tp type; };
1467 
1468  template<typename _Tp>
1469  struct __add_lvalue_reference_helper<_Tp, true>
1470  { typedef _Tp& type; };
1471 
1472  /// add_lvalue_reference
1473  template<typename _Tp>
1474  struct add_lvalue_reference
1475  : public __add_lvalue_reference_helper<_Tp>
1476  { };
1477 
1478  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
1479  struct __add_rvalue_reference_helper
1480  { typedef _Tp type; };
1481 
1482  template<typename _Tp>
1483  struct __add_rvalue_reference_helper<_Tp, true>
1484  { typedef _Tp&& type; };
1485 
1486  /// add_rvalue_reference
1487  template<typename _Tp>
1488  struct add_rvalue_reference
1489  : public __add_rvalue_reference_helper<_Tp>
1490  { };
1491 
1492 #if __cplusplus > 201103L
1493  /// Alias template for remove_reference
1494  template<typename _Tp>
1495  using remove_reference_t = typename remove_reference<_Tp>::type;
1496 
1497  /// Alias template for add_lvalue_reference
1498  template<typename _Tp>
1499  using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type;
1500 
1501  /// Alias template for add_rvalue_reference
1502  template<typename _Tp>
1503  using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type;
1504 #endif
1505 
1506  // Sign modifications.
1507 
1508  // Utility for constructing identically cv-qualified types.
1509  template<typename _Unqualified, bool _IsConst, bool _IsVol>
1510  struct __cv_selector;
1511 
1512  template<typename _Unqualified>
1513  struct __cv_selector<_Unqualified, false, false>
1514  { typedef _Unqualified __type; };
1515 
1516  template<typename _Unqualified>
1517  struct __cv_selector<_Unqualified, false, true>
1518  { typedef volatile _Unqualified __type; };
1519 
1520  template<typename _Unqualified>
1521  struct __cv_selector<_Unqualified, true, false>
1522  { typedef const _Unqualified __type; };
1523 
1524  template<typename _Unqualified>
1525  struct __cv_selector<_Unqualified, true, true>
1526  { typedef const volatile _Unqualified __type; };
1527 
1528  template<typename _Qualified, typename _Unqualified,
1529  bool _IsConst = is_const<_Qualified>::value,
1530  bool _IsVol = is_volatile<_Qualified>::value>
1531  class __match_cv_qualifiers
1532  {
1533  typedef __cv_selector<_Unqualified, _IsConst, _IsVol> __match;
1534 
1535  public:
1536  typedef typename __match::__type __type;
1537  };
1538 
1539  // Utility for finding the unsigned versions of signed integral types.
1540  template<typename _Tp>
1541  struct __make_unsigned
1542  { typedef _Tp __type; };
1543 
1544  template<>
1545  struct __make_unsigned<char>
1546  { typedef unsigned char __type; };
1547 
1548  template<>
1549  struct __make_unsigned<signed char>
1550  { typedef unsigned char __type; };
1551 
1552  template<>
1553  struct __make_unsigned<short>
1554  { typedef unsigned short __type; };
1555 
1556  template<>
1557  struct __make_unsigned<int>
1558  { typedef unsigned int __type; };
1559 
1560  template<>
1561  struct __make_unsigned<long>
1562  { typedef unsigned long __type; };
1563 
1564  template<>
1565  struct __make_unsigned<long long>
1566  { typedef unsigned long long __type; };
1567 
1568 #if defined(__GLIBCXX_TYPE_INT_N_0)
1569  template<>
1570  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_0>
1571  { typedef unsigned __GLIBCXX_TYPE_INT_N_0 __type; };
1572 #endif
1573 #if defined(__GLIBCXX_TYPE_INT_N_1)
1574  template<>
1575  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_1>
1576  { typedef unsigned __GLIBCXX_TYPE_INT_N_1 __type; };
1577 #endif
1578 #if defined(__GLIBCXX_TYPE_INT_N_2)
1579  template<>
1580  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_2>
1581  { typedef unsigned __GLIBCXX_TYPE_INT_N_2 __type; };
1582 #endif
1583 #if defined(__GLIBCXX_TYPE_INT_N_3)
1584  template<>
1585  struct __make_unsigned<__GLIBCXX_TYPE_INT_N_3>
1586  { typedef unsigned __GLIBCXX_TYPE_INT_N_3 __type; };
1587 #endif
1588 
1589  // Select between integral and enum: not possible to be both.
1590  template<typename _Tp,
1591  bool _IsInt = is_integral<_Tp>::value,
1592  bool _IsEnum = is_enum<_Tp>::value>
1593  class __make_unsigned_selector;
1594 
1595  template<typename _Tp>
1596  class __make_unsigned_selector<_Tp, true, false>
1597  {
1598  typedef __make_unsigned<typename remove_cv<_Tp>::type> __unsignedt;
1599  typedef typename __unsignedt::__type __unsigned_type;
1600  typedef __match_cv_qualifiers<_Tp, __unsigned_type> __cv_unsigned;
1601 
1602  public:
1603  typedef typename __cv_unsigned::__type __type;
1604  };
1605 
1606  template<typename _Tp>
1607  class __make_unsigned_selector<_Tp, false, true>
1608  {
1609  // With -fshort-enums, an enum may be as small as a char.
1610  typedef unsigned char __smallest;
1611  static const bool __b0 = sizeof(_Tp) <= sizeof(__smallest);
1612  static const bool __b1 = sizeof(_Tp) <= sizeof(unsigned short);
1613  static const bool __b2 = sizeof(_Tp) <= sizeof(unsigned int);
1614  static const bool __b3 = sizeof(_Tp) <= sizeof(unsigned long);
1615  typedef conditional<__b3, unsigned long, unsigned long long> __cond3;
1616  typedef typename __cond3::type __cond3_type;
1617  typedef conditional<__b2, unsigned int, __cond3_type> __cond2;
1618  typedef typename __cond2::type __cond2_type;
1619  typedef conditional<__b1, unsigned short, __cond2_type> __cond1;
1620  typedef typename __cond1::type __cond1_type;
1621 
1622  typedef typename conditional<__b0, __smallest, __cond1_type>::type
1623  __unsigned_type;
1624  typedef __match_cv_qualifiers<_Tp, __unsigned_type> __cv_unsigned;
1625 
1626  public:
1627  typedef typename __cv_unsigned::__type __type;
1628  };
1629 
1630  // Given an integral/enum type, return the corresponding unsigned
1631  // integer type.
1632  // Primary template.
1633  /// make_unsigned
1634  template<typename _Tp>
1635  struct make_unsigned
1636  { typedef typename __make_unsigned_selector<_Tp>::__type type; };
1637 
1638  // Integral, but don't define.
1639  template<>
1640  struct make_unsigned<bool>;
1641 
1642 
1643  // Utility for finding the signed versions of unsigned integral types.
1644  template<typename _Tp>
1645  struct __make_signed
1646  { typedef _Tp __type; };
1647 
1648  template<>
1649  struct __make_signed<char>
1650  { typedef signed char __type; };
1651 
1652  template<>
1653  struct __make_signed<unsigned char>
1654  { typedef signed char __type; };
1655 
1656  template<>
1657  struct __make_signed<unsigned short>
1658  { typedef signed short __type; };
1659 
1660  template<>
1661  struct __make_signed<unsigned int>
1662  { typedef signed int __type; };
1663 
1664  template<>
1665  struct __make_signed<unsigned long>
1666  { typedef signed long __type; };
1667 
1668  template<>
1669  struct __make_signed<unsigned long long>
1670  { typedef signed long long __type; };
1671 
1672 #if defined(__GLIBCXX_TYPE_INT_N_0)
1673  template<>
1674  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_0>
1675  { typedef __GLIBCXX_TYPE_INT_N_0 __type; };
1676 #endif
1677 #if defined(__GLIBCXX_TYPE_INT_N_1)
1678  template<>
1679  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_1>
1680  { typedef __GLIBCXX_TYPE_INT_N_1 __type; };
1681 #endif
1682 #if defined(__GLIBCXX_TYPE_INT_N_2)
1683  template<>
1684  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_2>
1685  { typedef __GLIBCXX_TYPE_INT_N_2 __type; };
1686 #endif
1687 #if defined(__GLIBCXX_TYPE_INT_N_3)
1688  template<>
1689  struct __make_signed<unsigned __GLIBCXX_TYPE_INT_N_3>
1690  { typedef __GLIBCXX_TYPE_INT_N_3 __type; };
1691 #endif
1692 
1693  // Select between integral and enum: not possible to be both.
1694  template<typename _Tp,
1695  bool _IsInt = is_integral<_Tp>::value,
1696  bool _IsEnum = is_enum<_Tp>::value>
1697  class __make_signed_selector;
1698 
1699  template<typename _Tp>
1700  class __make_signed_selector<_Tp, true, false>
1701  {
1702  typedef __make_signed<typename remove_cv<_Tp>::type> __signedt;
1703  typedef typename __signedt::__type __signed_type;
1704  typedef __match_cv_qualifiers<_Tp, __signed_type> __cv_signed;
1705 
1706  public:
1707  typedef typename __cv_signed::__type __type;
1708  };
1709 
1710  template<typename _Tp>
1711  class __make_signed_selector<_Tp, false, true>
1712  {
1713  typedef typename __make_unsigned_selector<_Tp>::__type __unsigned_type;
1714 
1715  public:
1716  typedef typename __make_signed_selector<__unsigned_type>::__type __type;
1717  };
1718 
1719  // Given an integral/enum type, return the corresponding signed
1720  // integer type.
1721  // Primary template.
1722  /// make_signed
1723  template<typename _Tp>
1724  struct make_signed
1725  { typedef typename __make_signed_selector<_Tp>::__type type; };
1726 
1727  // Integral, but don't define.
1728  template<>
1729  struct make_signed<bool>;
1730 
1731 #if __cplusplus > 201103L
1732  /// Alias template for make_signed
1733  template<typename _Tp>
1734  using make_signed_t = typename make_signed<_Tp>::type;
1735 
1736  /// Alias template for make_unsigned
1737  template<typename _Tp>
1738  using make_unsigned_t = typename make_unsigned<_Tp>::type;
1739 #endif
1740 
1741  // Array modifications.
1742 
1743  /// remove_extent
1744  template<typename _Tp>
1745  struct remove_extent
1746  { typedef _Tp type; };
1747 
1748  template<typename _Tp, std::size_t _Size>
1749  struct remove_extent<_Tp[_Size]>
1750  { typedef _Tp type; };
1751 
1752  template<typename _Tp>
1753  struct remove_extent<_Tp[]>
1754  { typedef _Tp type; };
1755 
1756  /// remove_all_extents
1757  template<typename _Tp>
1758  struct remove_all_extents
1759  { typedef _Tp type; };
1760 
1761  template<typename _Tp, std::size_t _Size>
1762  struct remove_all_extents<_Tp[_Size]>
1763  { typedef typename remove_all_extents<_Tp>::type type; };
1764 
1765  template<typename _Tp>
1766  struct remove_all_extents<_Tp[]>
1767  { typedef typename remove_all_extents<_Tp>::type type; };
1768 
1769 #if __cplusplus > 201103L
1770  /// Alias template for remove_extent
1771  template<typename _Tp>
1772  using remove_extent_t = typename remove_extent<_Tp>::type;
1773 
1774  /// Alias template for remove_all_extents
1775  template<typename _Tp>
1776  using remove_all_extents_t = typename remove_all_extents<_Tp>::type;
1777 #endif
1778 
1779  // Pointer modifications.
1780 
1781  template<typename _Tp, typename>
1782  struct __remove_pointer_helper
1783  { typedef _Tp type; };
1784 
1785  template<typename _Tp, typename _Up>
1786  struct __remove_pointer_helper<_Tp, _Up*>
1787  { typedef _Up type; };
1788 
1789  /// remove_pointer
1790  template<typename _Tp>
1791  struct remove_pointer
1792  : public __remove_pointer_helper<_Tp, typename remove_cv<_Tp>::type>
1793  { };
1794 
1795  /// add_pointer
1796  template<typename _Tp, bool = __or_<__is_referenceable<_Tp>,
1797  is_void<_Tp>>::value>
1798  struct __add_pointer_helper
1799  { typedef _Tp type; };
1800 
1801  template<typename _Tp>
1802  struct __add_pointer_helper<_Tp, true>
1803  { typedef typename remove_reference<_Tp>::type* type; };
1804 
1805  template<typename _Tp>
1806  struct add_pointer
1807  : public __add_pointer_helper<_Tp>
1808  { };
1809 
1810 #if __cplusplus > 201103L
1811  /// Alias template for remove_pointer
1812  template<typename _Tp>
1813  using remove_pointer_t = typename remove_pointer<_Tp>::type;
1814 
1815  /// Alias template for add_pointer
1816  template<typename _Tp>
1817  using add_pointer_t = typename add_pointer<_Tp>::type;
1818 #endif
1819 
1820  template<std::size_t _Len>
1821  struct __aligned_storage_msa
1822  {
1823  union __type
1824  {
1825  unsigned char __data[_Len];
1826  struct __attribute__((__aligned__)) { } __align;
1827  };
1828  };
1829 
1830  /**
1831  * @brief Alignment type.
1832  *
1833  * The value of _Align is a default-alignment which shall be the
1834  * most stringent alignment requirement for any C++ object type
1835  * whose size is no greater than _Len (3.9). The member typedef
1836  * type shall be a POD type suitable for use as uninitialized
1837  * storage for any object whose size is at most _Len and whose
1838  * alignment is a divisor of _Align.
1839  */
1840  template<std::size_t _Len, std::size_t _Align =
1841  __alignof__(typename __aligned_storage_msa<_Len>::__type)>
1842  struct aligned_storage
1843  {
1844  union type
1845  {
1846  unsigned char __data[_Len];
1847  struct __attribute__((__aligned__((_Align)))) { } __align;
1848  };
1849  };
1850 
1851  template <typename... _Types>
1852  struct __strictest_alignment
1853  {
1854  static const size_t _S_alignment = 0;
1855  static const size_t _S_size = 0;
1856  };
1857 
1858  template <typename _Tp, typename... _Types>
1859  struct __strictest_alignment<_Tp, _Types...>
1860  {
1861  static const size_t _S_alignment =
1862  alignof(_Tp) > __strictest_alignment<_Types...>::_S_alignment
1863  ? alignof(_Tp) : __strictest_alignment<_Types...>::_S_alignment;
1864  static const size_t _S_size =
1865  sizeof(_Tp) > __strictest_alignment<_Types...>::_S_size
1866  ? sizeof(_Tp) : __strictest_alignment<_Types...>::_S_size;
1867  };
1868 
1869  /**
1870  * @brief Provide aligned storage for types.
1871  *
1872  * [meta.trans.other]
1873  *
1874  * Provides aligned storage for any of the provided types of at
1875  * least size _Len.
1876  *
1877  * @see aligned_storage
1878  */
1879  template <size_t _Len, typename... _Types>
1880  struct aligned_union
1881  {
1882  private:
1883  static_assert(sizeof...(_Types) != 0, "At least one type is required");
1884 
1885  using __strictest = __strictest_alignment<_Types...>;
1886  static const size_t _S_len = _Len > __strictest::_S_size
1887  ? _Len : __strictest::_S_size;
1888  public:
1889  /// The value of the strictest alignment of _Types.
1890  static const size_t alignment_value = __strictest::_S_alignment;
1891  /// The storage.
1892  typedef typename aligned_storage<_S_len, alignment_value>::type type;
1893  };
1894 
1895  template <size_t _Len, typename... _Types>
1896  const size_t aligned_union<_Len, _Types...>::alignment_value;
1897 
1898  // Decay trait for arrays and functions, used for perfect forwarding
1899  // in make_pair, make_tuple, etc.
1900  template<typename _Up,
1901  bool _IsArray = is_array<_Up>::value,
1902  bool _IsFunction = is_function<_Up>::value>
1903  struct __decay_selector;
1904 
1905  // NB: DR 705.
1906  template<typename _Up>
1907  struct __decay_selector<_Up, false, false>
1908  { typedef typename remove_cv<_Up>::type __type; };
1909 
1910  template<typename _Up>
1911  struct __decay_selector<_Up, true, false>
1912  { typedef typename remove_extent<_Up>::type* __type; };
1913 
1914  template<typename _Up>
1915  struct __decay_selector<_Up, false, true>
1916  { typedef typename add_pointer<_Up>::type __type; };
1917 
1918  /// decay
1919  template<typename _Tp>
1920  class decay
1921  {
1922  typedef typename remove_reference<_Tp>::type __remove_type;
1923 
1924  public:
1925  typedef typename __decay_selector<__remove_type>::__type type;
1926  };
1927 
1928  template<typename _Tp>
1929  class reference_wrapper;
1930 
1931  // Helper which adds a reference to a type when given a reference_wrapper
1932  template<typename _Tp>
1933  struct __strip_reference_wrapper
1934  {
1935  typedef _Tp __type;
1936  };
1937 
1938  template<typename _Tp>
1939  struct __strip_reference_wrapper<reference_wrapper<_Tp> >
1940  {
1941  typedef _Tp& __type;
1942  };
1943 
1944  template<typename _Tp>
1945  struct __decay_and_strip
1946  {
1947  typedef typename __strip_reference_wrapper<
1948  typename decay<_Tp>::type>::__type __type;
1949  };
1950 
1951 
1952  // Primary template.
1953  /// Define a member typedef @c type only if a boolean constant is true.
1954  template<bool, typename _Tp = void>
1955  struct enable_if
1956  { };
1957 
1958  // Partial specialization for true.
1959  template<typename _Tp>
1960  struct enable_if<true, _Tp>
1961  { typedef _Tp type; };
1962 
1963  template<typename... _Cond>
1964  using _Require = typename enable_if<__and_<_Cond...>::value>::type;
1965 
1966  // Primary template.
1967  /// Define a member typedef @c type to one of two argument types.
1968  template<bool _Cond, typename _Iftrue, typename _Iffalse>
1969  struct conditional
1970  { typedef _Iftrue type; };
1971 
1972  // Partial specialization for false.
1973  template<typename _Iftrue, typename _Iffalse>
1974  struct conditional<false, _Iftrue, _Iffalse>
1975  { typedef _Iffalse type; };
1976 
1977  /// common_type
1978  template<typename... _Tp>
1979  struct common_type;
1980 
1981  // Sfinae-friendly common_type implementation:
1982 
1983  struct __do_common_type_impl
1984  {
1985  template<typename _Tp, typename _Up>
1986  static __success_type<typename decay<decltype
1987  (true ? std::declval<_Tp>()
1988  : std::declval<_Up>())>::type> _S_test(int);
1989 
1990  template<typename, typename>
1991  static __failure_type _S_test(...);
1992  };
1993 
1994  template<typename _Tp, typename _Up>
1995  struct __common_type_impl
1996  : private __do_common_type_impl
1997  {
1998  typedef decltype(_S_test<_Tp, _Up>(0)) type;
1999  };
2000 
2001  struct __do_member_type_wrapper
2002  {
2003  template<typename _Tp>
2004  static __success_type<typename _Tp::type> _S_test(int);
2005 
2006  template<typename>
2007  static __failure_type _S_test(...);
2008  };
2009 
2010  template<typename _Tp>
2011  struct __member_type_wrapper
2012  : private __do_member_type_wrapper
2013  {
2014  typedef decltype(_S_test<_Tp>(0)) type;
2015  };
2016 
2017  template<typename _CTp, typename... _Args>
2018  struct __expanded_common_type_wrapper
2019  {
2020  typedef common_type<typename _CTp::type, _Args...> type;
2021  };
2022 
2023  template<typename... _Args>
2024  struct __expanded_common_type_wrapper<__failure_type, _Args...>
2025  { typedef __failure_type type; };
2026 
2027  template<>
2028  struct common_type<>
2029  { };
2030 
2031  template<typename _Tp>
2032  struct common_type<_Tp>
2033  : common_type<_Tp, _Tp>
2034  { };
2035 
2036  template<typename _Tp, typename _Up>
2037  struct common_type<_Tp, _Up>
2038  : public __common_type_impl<_Tp, _Up>::type
2039  { };
2040 
2041  template<typename _Tp, typename _Up, typename... _Vp>
2042  struct common_type<_Tp, _Up, _Vp...>
2043  : public __expanded_common_type_wrapper<typename __member_type_wrapper<
2044  common_type<_Tp, _Up>>::type, _Vp...>::type
2045  { };
2046 
2047  /// The underlying type of an enum.
2048  template<typename _Tp>
2049  struct underlying_type
2050  {
2051  typedef __underlying_type(_Tp) type;
2052  };
2053 
2054  template<typename _Tp>
2055  struct __declval_protector
2056  {
2057  static const bool __stop = false;
2058  };
2059 
2060  template<typename _Tp>
2061  auto declval() noexcept -> decltype(__declval<_Tp>(0))
2062  {
2063  static_assert(__declval_protector<_Tp>::__stop,
2064  "declval() must not be used!");
2065  return __declval<_Tp>(0);
2066  }
2067 
2068  // wchar_t, char16_t and char32_t are integral types but are neither
2069  // signed integer types nor unsigned integer types, so must be
2070  // transformed to the integer type with the smallest rank that has the
2071  // same size and signedness.
2072  // Use the partial specialization for enumeration types to do that,
2073  // which means these explicit specializations must be defined after
2074  // std::conditional has been defined.
2075 
2076 #if defined(_GLIBCXX_USE_WCHAR_T)
2077  template<>
2078  struct __make_unsigned<wchar_t>
2079  {
2080  using __type
2081  = typename __make_unsigned_selector<wchar_t, false, true>::__type;
2082  };
2083 
2084  template<>
2085  struct __make_signed<wchar_t>
2086  {
2087  using __type
2088  = typename __make_signed_selector<wchar_t, false, true>::__type;
2089  };
2090 #endif
2091 
2092  template<>
2093  struct __make_unsigned<char16_t>
2094  {
2095  using __type
2096  = typename __make_unsigned_selector<char16_t, false, true>::__type;
2097  };
2098 
2099  template<>
2100  struct __make_signed<char16_t>
2101  {
2102  using __type
2103  = typename __make_signed_selector<char16_t, false, true>::__type;
2104  };
2105 
2106  template<>
2107  struct __make_unsigned<char32_t>
2108  {
2109  using __type
2110  = typename __make_unsigned_selector<char32_t, false, true>::__type;
2111  };
2112 
2113  template<>
2114  struct __make_signed<char32_t>
2115  {
2116  using __type
2117  = typename __make_signed_selector<char32_t, false, true>::__type;
2118  };
2119 
2120 
2121  /// result_of
2122  template<typename _Signature>
2123  class result_of;
2124 
2125  // Sfinae-friendly result_of implementation:
2126 
2127 #define __cpp_lib_result_of_sfinae 201210
2128 
2129  struct __invoke_memfun_ref { };
2130  struct __invoke_memfun_deref { };
2131  struct __invoke_memobj_ref { };
2132  struct __invoke_memobj_deref { };
2133  struct __invoke_other { };
2134 
2135  // Associate a tag type with a specialization of __success_type.
2136  template<typename _Tp, typename _Tag>
2137  struct __result_of_success : __success_type<_Tp>
2138  { using __invoke_type = _Tag; };
2139 
2140  // [func.require] paragraph 1 bullet 1:
2141  struct __result_of_memfun_ref_impl
2142  {
2143  template<typename _Fp, typename _Tp1, typename... _Args>
2144  static __result_of_success<decltype(
2145  (std::declval<_Tp1>().*std::declval<_Fp>())(std::declval<_Args>()...)
2146  ), __invoke_memfun_ref> _S_test(int);
2147 
2148  template<typename...>
2149  static __failure_type _S_test(...);
2150  };
2151 
2152  template<typename _MemPtr, typename _Arg, typename... _Args>
2153  struct __result_of_memfun_ref
2154  : private __result_of_memfun_ref_impl
2155  {
2156  typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
2157  };
2158 
2159  // [func.require] paragraph 1 bullet 2:
2160  struct __result_of_memfun_deref_impl
2161  {
2162  template<typename _Fp, typename _Tp1, typename... _Args>
2163  static __result_of_success<decltype(
2164  ((*std::declval<_Tp1>()).*std::declval<_Fp>())(std::declval<_Args>()...)
2165  ), __invoke_memfun_deref> _S_test(int);
2166 
2167  template<typename...>
2168  static __failure_type _S_test(...);
2169  };
2170 
2171  template<typename _MemPtr, typename _Arg, typename... _Args>
2172  struct __result_of_memfun_deref
2173  : private __result_of_memfun_deref_impl
2174  {
2175  typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
2176  };
2177 
2178  // [func.require] paragraph 1 bullet 3:
2179  struct __result_of_memobj_ref_impl
2180  {
2181  template<typename _Fp, typename _Tp1>
2182  static __result_of_success<decltype(
2183  std::declval<_Tp1>().*std::declval<_Fp>()
2184  ), __invoke_memobj_ref> _S_test(int);
2185 
2186  template<typename, typename>
2187  static __failure_type _S_test(...);
2188  };
2189 
2190  template<typename _MemPtr, typename _Arg>
2191  struct __result_of_memobj_ref
2192  : private __result_of_memobj_ref_impl
2193  {
2194  typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
2195  };
2196 
2197  // [func.require] paragraph 1 bullet 4:
2198  struct __result_of_memobj_deref_impl
2199  {
2200  template<typename _Fp, typename _Tp1>
2201  static __result_of_success<decltype(
2202  (*std::declval<_Tp1>()).*std::declval<_Fp>()
2203  ), __invoke_memobj_deref> _S_test(int);
2204 
2205  template<typename, typename>
2206  static __failure_type _S_test(...);
2207  };
2208 
2209  template<typename _MemPtr, typename _Arg>
2210  struct __result_of_memobj_deref
2211  : private __result_of_memobj_deref_impl
2212  {
2213  typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
2214  };
2215 
2216  template<typename _MemPtr, typename _Arg>
2217  struct __result_of_memobj;
2218 
2219  template<typename _Res, typename _Class, typename _Arg>
2220  struct __result_of_memobj<_Res _Class::*, _Arg>
2221  {
2222  typedef typename remove_cv<typename remove_reference<
2223  _Arg>::type>::type _Argval;
2224  typedef _Res _Class::* _MemPtr;
2225  typedef typename conditional<__or_<is_same<_Argval, _Class>,
2226  is_base_of<_Class, _Argval>>::value,
2227  __result_of_memobj_ref<_MemPtr, _Arg>,
2228  __result_of_memobj_deref<_MemPtr, _Arg>
2229  >::type::type type;
2230  };
2231 
2232  template<typename _MemPtr, typename _Arg, typename... _Args>
2233  struct __result_of_memfun;
2234 
2235  template<typename _Res, typename _Class, typename _Arg, typename... _Args>
2236  struct __result_of_memfun<_Res _Class::*, _Arg, _Args...>
2237  {
2238  typedef typename remove_cv<typename remove_reference<
2239  _Arg>::type>::type _Argval;
2240  typedef _Res _Class::* _MemPtr;
2241  typedef typename conditional<__or_<is_same<_Argval, _Class>,
2242  is_base_of<_Class, _Argval>>::value,
2243  __result_of_memfun_ref<_MemPtr, _Arg, _Args...>,
2244  __result_of_memfun_deref<_MemPtr, _Arg, _Args...>
2245  >::type::type type;
2246  };
2247 
2248  // _GLIBCXX_RESOLVE_LIB_DEFECTS
2249  // 2219. INVOKE-ing a pointer to member with a reference_wrapper
2250  // as the object expression
2251 
2252  // Used by result_of, invoke etc. to unwrap a reference_wrapper.
2253  template<typename _Tp, typename _Up = typename decay<_Tp>::type>
2254  struct __inv_unwrap
2255  {
2256  using type = _Tp;
2257  };
2258 
2259  template<typename _Tp, typename _Up>
2260  struct __inv_unwrap<_Tp, reference_wrapper<_Up>>
2261  {
2262  using type = _Up&;
2263  };
2264 
2265  template<bool, bool, typename _Functor, typename... _ArgTypes>
2266  struct __result_of_impl
2267  {
2268  typedef __failure_type type;
2269  };
2270 
2271  template<typename _MemPtr, typename _Arg>
2272  struct __result_of_impl<true, false, _MemPtr, _Arg>
2273  : public __result_of_memobj<typename decay<_MemPtr>::type,
2274  typename __inv_unwrap<_Arg>::type>
2275  { };
2276 
2277  template<typename _MemPtr, typename _Arg, typename... _Args>
2278  struct __result_of_impl<false, true, _MemPtr, _Arg, _Args...>
2279  : public __result_of_memfun<typename decay<_MemPtr>::type,
2280  typename __inv_unwrap<_Arg>::type, _Args...>
2281  { };
2282 
2283  // [func.require] paragraph 1 bullet 5:
2284  struct __result_of_other_impl
2285  {
2286  template<typename _Fn, typename... _Args>
2287  static __result_of_success<decltype(
2288  std::declval<_Fn>()(std::declval<_Args>()...)
2289  ), __invoke_other> _S_test(int);
2290 
2291  template<typename...>
2292  static __failure_type _S_test(...);
2293  };
2294 
2295  template<typename _Functor, typename... _ArgTypes>
2296  struct __result_of_impl<false, false, _Functor, _ArgTypes...>
2297  : private __result_of_other_impl
2298  {
2299  typedef decltype(_S_test<_Functor, _ArgTypes...>(0)) type;
2300  };
2301 
2302  // __invoke_result (std::invoke_result for C++11)
2303  template<typename _Functor, typename... _ArgTypes>
2304  struct __invoke_result
2305  : public __result_of_impl<
2306  is_member_object_pointer<
2307  typename remove_reference<_Functor>::type
2308  >::value,
2309  is_member_function_pointer<
2310  typename remove_reference<_Functor>::type
2311  >::value,
2312  _Functor, _ArgTypes...
2313  >::type
2314  { };
2315 
2316  template<typename _Functor, typename... _ArgTypes>
2317  struct result_of<_Functor(_ArgTypes...)>
2318  : public __invoke_result<_Functor, _ArgTypes...>
2319  { };
2320 
2321 #if __cplusplus >= 201402L
2322  /// Alias template for aligned_storage
2323  template<size_t _Len, size_t _Align =
2324  __alignof__(typename __aligned_storage_msa<_Len>::__type)>
2325  using aligned_storage_t = typename aligned_storage<_Len, _Align>::type;
2326 
2327  template <size_t _Len, typename... _Types>
2328  using aligned_union_t = typename aligned_union<_Len, _Types...>::type;
2329 
2330  /// Alias template for decay
2331  template<typename _Tp>
2332  using decay_t = typename decay<_Tp>::type;
2333 
2334  /// Alias template for enable_if
2335  template<bool _Cond, typename _Tp = void>
2336  using enable_if_t = typename enable_if<_Cond, _Tp>::type;
2337 
2338  /// Alias template for conditional
2339  template<bool _Cond, typename _Iftrue, typename _Iffalse>
2340  using conditional_t = typename conditional<_Cond, _Iftrue, _Iffalse>::type;
2341 
2342  /// Alias template for common_type
2343  template<typename... _Tp>
2344  using common_type_t = typename common_type<_Tp...>::type;
2345 
2346  /// Alias template for underlying_type
2347  template<typename _Tp>
2348  using underlying_type_t = typename underlying_type<_Tp>::type;
2349 
2350  /// Alias template for result_of
2351  template<typename _Tp>
2352  using result_of_t = typename result_of<_Tp>::type;
2353 #endif // C++14
2354 
2355  // __enable_if_t (std::enable_if_t for C++11)
2356  template<bool _Cond, typename _Tp = void>
2357  using __enable_if_t = typename enable_if<_Cond, _Tp>::type;
2358 
2359  // __void_t (std::void_t for C++11)
2360  template<typename...> using __void_t = void;
2361 
2362 #if __cplusplus >= 201703L || !defined(__STRICT_ANSI__) // c++17 or gnu++11
2363 #define __cpp_lib_void_t 201411
2364  /// A metafunction that always yields void, used for detecting valid types.
2365  template<typename...> using void_t = void;
2366 #endif
2367 
2368  /// Implementation of the detection idiom (negative case).
2369  template<typename _Default, typename _AlwaysVoid,
2370  template<typename...> class _Op, typename... _Args>
2371  struct __detector
2372  {
2373  using value_t = false_type;
2374  using type = _Default;
2375  };
2376 
2377  /// Implementation of the detection idiom (positive case).
2378  template<typename _Default, template<typename...> class _Op,
2379  typename... _Args>
2380  struct __detector<_Default, __void_t<_Op<_Args...>>, _Op, _Args...>
2381  {
2382  using value_t = true_type;
2383  using type = _Op<_Args...>;
2384  };
2385 
2386  // Detect whether _Op<_Args...> is a valid type, use _Default if not.
2387  template<typename _Default, template<typename...> class _Op,
2388  typename... _Args>
2389  using __detected_or = __detector<_Default, void, _Op, _Args...>;
2390 
2391  // _Op<_Args...> if that is a valid type, otherwise _Default.
2392  template<typename _Default, template<typename...> class _Op,
2393  typename... _Args>
2394  using __detected_or_t
2395  = typename __detected_or<_Default, _Op, _Args...>::type;
2396 
2397  /// @} group metaprogramming
2398 
2399  /**
2400  * Use SFINAE to determine if the type _Tp has a publicly-accessible
2401  * member type _NTYPE.
2402  */
2403 #define _GLIBCXX_HAS_NESTED_TYPE(_NTYPE) \
2404  template<typename _Tp, typename = __void_t<>> \
2405  struct __has_##_NTYPE \
2406  : false_type \
2407  { }; \
2408  template<typename _Tp> \
2409  struct __has_##_NTYPE<_Tp, __void_t<typename _Tp::_NTYPE>> \
2410  : true_type \
2411  { };
2412 
2413  template <typename _Tp>
2414  struct __is_swappable;
2415 
2416  template <typename _Tp>
2417  struct __is_nothrow_swappable;
2418 
2419  template<typename... _Elements>
2420  class tuple;
2421 
2422  template<typename>
2423  struct __is_tuple_like_impl : false_type
2424  { };
2425 
2426  template<typename... _Tps>
2427  struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
2428  { };
2429 
2430  // Internal type trait that allows us to sfinae-protect tuple_cat.
2431  template<typename _Tp>
2432  struct __is_tuple_like
2433  : public __is_tuple_like_impl<typename remove_cv<
2434  typename remove_reference<_Tp>::type>::type>::type
2435  { };
2436 
2437  template<typename _Tp>
2438  inline
2439  typename enable_if<__and_<__not_<__is_tuple_like<_Tp>>,
2440  is_move_constructible<_Tp>,
2441  is_move_assignable<_Tp>>::value>::type
2442  swap(_Tp&, _Tp&)
2443  noexcept(__and_<is_nothrow_move_constructible<_Tp>,
2444  is_nothrow_move_assignable<_Tp>>::value);
2445 
2446  template<typename _Tp, size_t _Nm>
2447  inline
2448  typename enable_if<__is_swappable<_Tp>::value>::type
2449  swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
2450  noexcept(__is_nothrow_swappable<_Tp>::value);
2451 
2452  namespace __swappable_details {
2453  using std::swap;
2454 
2455  struct __do_is_swappable_impl
2456  {
2457  template<typename _Tp, typename
2458  = decltype(swap(std::declval<_Tp&>(), std::declval<_Tp&>()))>
2459  static true_type __test(int);
2460 
2461  template<typename>
2462  static false_type __test(...);
2463  };
2464 
2465  struct __do_is_nothrow_swappable_impl
2466  {
2467  template<typename _Tp>
2468  static __bool_constant<
2469  noexcept(swap(std::declval<_Tp&>(), std::declval<_Tp&>()))
2470  > __test(int);
2471 
2472  template<typename>
2473  static false_type __test(...);
2474  };
2475 
2476  } // namespace __swappable_details
2477 
2478  template<typename _Tp>
2479  struct __is_swappable_impl
2480  : public __swappable_details::__do_is_swappable_impl
2481  {
2482  typedef decltype(__test<_Tp>(0)) type;
2483  };
2484 
2485  template<typename _Tp>
2486  struct __is_nothrow_swappable_impl
2487  : public __swappable_details::__do_is_nothrow_swappable_impl
2488  {
2489  typedef decltype(__test<_Tp>(0)) type;
2490  };
2491 
2492  template<typename _Tp>
2493  struct __is_swappable
2494  : public __is_swappable_impl<_Tp>::type
2495  { };
2496 
2497  template<typename _Tp>
2498  struct __is_nothrow_swappable
2499  : public __is_nothrow_swappable_impl<_Tp>::type
2500  { };
2501 
2502 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
2503 #define __cpp_lib_is_swappable 201603
2504  /// Metafunctions used for detecting swappable types: p0185r1
2505 
2506  /// is_swappable
2507  template<typename _Tp>
2508  struct is_swappable
2509  : public __is_swappable_impl<_Tp>::type
2510  { };
2511 
2512  /// is_nothrow_swappable
2513  template<typename _Tp>
2514  struct is_nothrow_swappable
2515  : public __is_nothrow_swappable_impl<_Tp>::type
2516  { };
2517 
2518 #if __cplusplus >= 201402L
2519  /// is_swappable_v
2520  template<typename _Tp>
2521  _GLIBCXX17_INLINE constexpr bool is_swappable_v =
2522  is_swappable<_Tp>::value;
2523 
2524  /// is_nothrow_swappable_v
2525  template<typename _Tp>
2526  _GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_v =
2527  is_nothrow_swappable<_Tp>::value;
2528 #endif // __cplusplus >= 201402L
2529 
2530  namespace __swappable_with_details {
2531  using std::swap;
2532 
2533  struct __do_is_swappable_with_impl
2534  {
2535  template<typename _Tp, typename _Up, typename
2536  = decltype(swap(std::declval<_Tp>(), std::declval<_Up>())),
2537  typename
2538  = decltype(swap(std::declval<_Up>(), std::declval<_Tp>()))>
2539  static true_type __test(int);
2540 
2541  template<typename, typename>
2542  static false_type __test(...);
2543  };
2544 
2545  struct __do_is_nothrow_swappable_with_impl
2546  {
2547  template<typename _Tp, typename _Up>
2548  static __bool_constant<
2549  noexcept(swap(std::declval<_Tp>(), std::declval<_Up>()))
2550  &&
2551  noexcept(swap(std::declval<_Up>(), std::declval<_Tp>()))
2552  > __test(int);
2553 
2554  template<typename, typename>
2555  static false_type __test(...);
2556  };
2557 
2558  } // namespace __swappable_with_details
2559 
2560  template<typename _Tp, typename _Up>
2561  struct __is_swappable_with_impl
2562  : public __swappable_with_details::__do_is_swappable_with_impl
2563  {
2564  typedef decltype(__test<_Tp, _Up>(0)) type;
2565  };
2566 
2567  // Optimization for the homogenous lvalue case, not required:
2568  template<typename _Tp>
2569  struct __is_swappable_with_impl<_Tp&, _Tp&>
2570  : public __swappable_details::__do_is_swappable_impl
2571  {
2572  typedef decltype(__test<_Tp&>(0)) type;
2573  };
2574 
2575  template<typename _Tp, typename _Up>
2576  struct __is_nothrow_swappable_with_impl
2577  : public __swappable_with_details::__do_is_nothrow_swappable_with_impl
2578  {
2579  typedef decltype(__test<_Tp, _Up>(0)) type;
2580  };
2581 
2582  // Optimization for the homogenous lvalue case, not required:
2583  template<typename _Tp>
2584  struct __is_nothrow_swappable_with_impl<_Tp&, _Tp&>
2585  : public __swappable_details::__do_is_nothrow_swappable_impl
2586  {
2587  typedef decltype(__test<_Tp&>(0)) type;
2588  };
2589 
2590  /// is_swappable_with
2591  template<typename _Tp, typename _Up>
2592  struct is_swappable_with
2593  : public __is_swappable_with_impl<_Tp, _Up>::type
2594  { };
2595 
2596  /// is_nothrow_swappable_with
2597  template<typename _Tp, typename _Up>
2598  struct is_nothrow_swappable_with
2599  : public __is_nothrow_swappable_with_impl<_Tp, _Up>::type
2600  { };
2601 
2602 #if __cplusplus >= 201402L
2603  /// is_swappable_with_v
2604  template<typename _Tp, typename _Up>
2605  _GLIBCXX17_INLINE constexpr bool is_swappable_with_v =
2606  is_swappable_with<_Tp, _Up>::value;
2607 
2608  /// is_nothrow_swappable_with_v
2609  template<typename _Tp, typename _Up>
2610  _GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_with_v =
2611  is_nothrow_swappable_with<_Tp, _Up>::value;
2612 #endif // __cplusplus >= 201402L
2613 
2614 #endif// c++1z or gnu++11
2615 
2616  // __is_invocable (std::is_invocable for C++11)
2617 
2618  template<typename _Result, typename _Ret, typename = void>
2619  struct __is_invocable_impl : false_type { };
2620 
2621  template<typename _Result, typename _Ret>
2622  struct __is_invocable_impl<_Result, _Ret, __void_t<typename _Result::type>>
2623  : __or_<is_void<_Ret>, is_convertible<typename _Result::type, _Ret>>::type
2624  { };
2625 
2626  template<typename _Fn, typename... _ArgTypes>
2627  struct __is_invocable
2628  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>::type
2629  { };
2630 
2631  template<typename _Fn, typename _Tp, typename... _Args>
2632  constexpr bool __call_is_nt(__invoke_memfun_ref)
2633  {
2634  using _Up = typename __inv_unwrap<_Tp>::type;
2635  return noexcept((std::declval<_Up>().*std::declval<_Fn>())(
2636  std::declval<_Args>()...));
2637  }
2638 
2639  template<typename _Fn, typename _Tp, typename... _Args>
2640  constexpr bool __call_is_nt(__invoke_memfun_deref)
2641  {
2642  return noexcept(((*std::declval<_Tp>()).*std::declval<_Fn>())(
2643  std::declval<_Args>()...));
2644  }
2645 
2646  template<typename _Fn, typename _Tp>
2647  constexpr bool __call_is_nt(__invoke_memobj_ref)
2648  {
2649  using _Up = typename __inv_unwrap<_Tp>::type;
2650  return noexcept(std::declval<_Up>().*std::declval<_Fn>());
2651  }
2652 
2653  template<typename _Fn, typename _Tp>
2654  constexpr bool __call_is_nt(__invoke_memobj_deref)
2655  {
2656  return noexcept((*std::declval<_Tp>()).*std::declval<_Fn>());
2657  }
2658 
2659  template<typename _Fn, typename... _Args>
2660  constexpr bool __call_is_nt(__invoke_other)
2661  {
2662  return noexcept(std::declval<_Fn>()(std::declval<_Args>()...));
2663  }
2664 
2665  template<typename _Result, typename _Fn, typename... _Args>
2666  struct __call_is_nothrow
2667  : __bool_constant<
2668  std::__call_is_nt<_Fn, _Args...>(typename _Result::__invoke_type{})
2669  >
2670  { };
2671 
2672  template<typename _Fn, typename... _Args>
2673  using __call_is_nothrow_
2674  = __call_is_nothrow<__invoke_result<_Fn, _Args...>, _Fn, _Args...>;
2675 
2676  // __is_nothrow_invocable (std::is_nothrow_invocable for C++11)
2677  template<typename _Fn, typename... _Args>
2678  struct __is_nothrow_invocable
2679  : __and_<__is_invocable<_Fn, _Args...>,
2680  __call_is_nothrow_<_Fn, _Args...>>::type
2681  { };
2682 
2683  struct __nonesuch {
2684  __nonesuch() = delete;
2685  ~__nonesuch() = delete;
2686  __nonesuch(__nonesuch const&) = delete;
2687  void operator=(__nonesuch const&) = delete;
2688  };
2689 
2690 #if __cplusplus >= 201703L
2691 # define __cpp_lib_is_invocable 201703
2692 
2693  /// std::invoke_result
2694  template<typename _Functor, typename... _ArgTypes>
2695  struct invoke_result
2696  : public __invoke_result<_Functor, _ArgTypes...>
2697  { };
2698 
2699  /// std::invoke_result_t
2700  template<typename _Fn, typename... _Args>
2701  using invoke_result_t = typename invoke_result<_Fn, _Args...>::type;
2702 
2703  /// std::is_invocable
2704  template<typename _Fn, typename... _ArgTypes>
2705  struct is_invocable
2706  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>::type
2707  { };
2708 
2709  /// std::is_invocable_r
2710  template<typename _Ret, typename _Fn, typename... _ArgTypes>
2711  struct is_invocable_r
2712  : __is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, _Ret>::type
2713  { };
2714 
2715  /// std::is_nothrow_invocable
2716  template<typename _Fn, typename... _ArgTypes>
2717  struct is_nothrow_invocable
2718  : __and_<__is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>,
2719  __call_is_nothrow_<_Fn, _ArgTypes...>>::type
2720  { };
2721 
2722  template<typename _Result, typename _Ret, typename = void>
2723  struct __is_nt_invocable_impl : false_type { };
2724 
2725  template<typename _Result, typename _Ret>
2726  struct __is_nt_invocable_impl<_Result, _Ret,
2727  __void_t<typename _Result::type>>
2728  : __or_<is_void<_Ret>,
2729  __and_<is_convertible<typename _Result::type, _Ret>,
2730  is_nothrow_constructible<_Ret, typename _Result::type>>>
2731  { };
2732 
2733  /// std::is_nothrow_invocable_r
2734  template<typename _Ret, typename _Fn, typename... _ArgTypes>
2735  struct is_nothrow_invocable_r
2736  : __and_<__is_nt_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, _Ret>,
2737  __call_is_nothrow_<_Fn, _ArgTypes...>>::type
2738  { };
2739 
2740  /// std::is_invocable_v
2741  template<typename _Fn, typename... _Args>
2742  inline constexpr bool is_invocable_v = is_invocable<_Fn, _Args...>::value;
2743 
2744  /// std::is_nothrow_invocable_v
2745  template<typename _Fn, typename... _Args>
2746  inline constexpr bool is_nothrow_invocable_v
2747  = is_nothrow_invocable<_Fn, _Args...>::value;
2748 
2749  /// std::is_invocable_r_v
2750  template<typename _Fn, typename... _Args>
2751  inline constexpr bool is_invocable_r_v
2752  = is_invocable_r<_Fn, _Args...>::value;
2753 
2754  /// std::is_nothrow_invocable_r_v
2755  template<typename _Fn, typename... _Args>
2756  inline constexpr bool is_nothrow_invocable_r_v
2757  = is_nothrow_invocable_r<_Fn, _Args...>::value;
2758 #endif // C++17
2759 
2760 #if __cplusplus >= 201703L
2761 # define __cpp_lib_type_trait_variable_templates 201510L
2762 template <typename _Tp>
2763  inline constexpr bool is_void_v = is_void<_Tp>::value;
2764 template <typename _Tp>
2765  inline constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value;
2766 template <typename _Tp>
2767  inline constexpr bool is_integral_v = is_integral<_Tp>::value;
2768 template <typename _Tp>
2769  inline constexpr bool is_floating_point_v = is_floating_point<_Tp>::value;
2770 template <typename _Tp>
2771  inline constexpr bool is_array_v = is_array<_Tp>::value;
2772 template <typename _Tp>
2773  inline constexpr bool is_pointer_v = is_pointer<_Tp>::value;
2774 template <typename _Tp>
2775  inline constexpr bool is_lvalue_reference_v =
2776  is_lvalue_reference<_Tp>::value;
2777 template <typename _Tp>
2778  inline constexpr bool is_rvalue_reference_v =
2779  is_rvalue_reference<_Tp>::value;
2780 template <typename _Tp>
2781  inline constexpr bool is_member_object_pointer_v =
2782  is_member_object_pointer<_Tp>::value;
2783 template <typename _Tp>
2784  inline constexpr bool is_member_function_pointer_v =
2785  is_member_function_pointer<_Tp>::value;
2786 template <typename _Tp>
2787  inline constexpr bool is_enum_v = is_enum<_Tp>::value;
2788 template <typename _Tp>
2789  inline constexpr bool is_union_v = is_union<_Tp>::value;
2790 template <typename _Tp>
2791  inline constexpr bool is_class_v = is_class<_Tp>::value;
2792 template <typename _Tp>
2793  inline constexpr bool is_function_v = is_function<_Tp>::value;
2794 template <typename _Tp>
2795  inline constexpr bool is_reference_v = is_reference<_Tp>::value;
2796 template <typename _Tp>
2797  inline constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
2798 template <typename _Tp>
2799  inline constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
2800 template <typename _Tp>
2801  inline constexpr bool is_object_v = is_object<_Tp>::value;
2802 template <typename _Tp>
2803  inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
2804 template <typename _Tp>
2805  inline constexpr bool is_compound_v = is_compound<_Tp>::value;
2806 template <typename _Tp>
2807  inline constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
2808 template <typename _Tp>
2809  inline constexpr bool is_const_v = is_const<_Tp>::value;
2810 template <typename _Tp>
2811  inline constexpr bool is_volatile_v = is_volatile<_Tp>::value;
2812 template <typename _Tp>
2813  inline constexpr bool is_trivial_v = is_trivial<_Tp>::value;
2814 template <typename _Tp>
2815  inline constexpr bool is_trivially_copyable_v =
2816  is_trivially_copyable<_Tp>::value;
2817 template <typename _Tp>
2818  inline constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
2819 template <typename _Tp>
2820  inline constexpr bool is_pod_v = is_pod<_Tp>::value;
2821 template <typename _Tp>
2822  inline constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
2823 template <typename _Tp>
2824  inline constexpr bool is_empty_v = is_empty<_Tp>::value;
2825 template <typename _Tp>
2826  inline constexpr bool is_polymorphic_v = is_polymorphic<_Tp>::value;
2827 template <typename _Tp>
2828  inline constexpr bool is_abstract_v = is_abstract<_Tp>::value;
2829 template <typename _Tp>
2830  inline constexpr bool is_final_v = is_final<_Tp>::value;
2831 template <typename _Tp>
2832  inline constexpr bool is_signed_v = is_signed<_Tp>::value;
2833 template <typename _Tp>
2834  inline constexpr bool is_unsigned_v = is_unsigned<_Tp>::value;
2835 template <typename _Tp, typename... _Args>
2836  inline constexpr bool is_constructible_v =
2837  is_constructible<_Tp, _Args...>::value;
2838 template <typename _Tp>
2839  inline constexpr bool is_default_constructible_v =
2840  is_default_constructible<_Tp>::value;
2841 template <typename _Tp>
2842  inline constexpr bool is_copy_constructible_v =
2843  is_copy_constructible<_Tp>::value;
2844 template <typename _Tp>
2845  inline constexpr bool is_move_constructible_v =
2846  is_move_constructible<_Tp>::value;
2847 template <typename _Tp, typename _Up>
2848  inline constexpr bool is_assignable_v = is_assignable<_Tp, _Up>::value;
2849 template <typename _Tp>
2850  inline constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value;
2851 template <typename _Tp>
2852  inline constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value;
2853 template <typename _Tp>
2854  inline constexpr bool is_destructible_v = is_destructible<_Tp>::value;
2855 template <typename _Tp, typename... _Args>
2856  inline constexpr bool is_trivially_constructible_v =
2857  is_trivially_constructible<_Tp, _Args...>::value;
2858 template <typename _Tp>
2859  inline constexpr bool is_trivially_default_constructible_v =
2860  is_trivially_default_constructible<_Tp>::value;
2861 template <typename _Tp>
2862  inline constexpr bool is_trivially_copy_constructible_v =
2863  is_trivially_copy_constructible<_Tp>::value;
2864 template <typename _Tp>
2865  inline constexpr bool is_trivially_move_constructible_v =
2866  is_trivially_move_constructible<_Tp>::value;
2867 template <typename _Tp, typename _Up>
2868  inline constexpr bool is_trivially_assignable_v =
2869  is_trivially_assignable<_Tp, _Up>::value;
2870 template <typename _Tp>
2871  inline constexpr bool is_trivially_copy_assignable_v =
2872  is_trivially_copy_assignable<_Tp>::value;
2873 template <typename _Tp>
2874  inline constexpr bool is_trivially_move_assignable_v =
2875  is_trivially_move_assignable<_Tp>::value;
2876 template <typename _Tp>
2877  inline constexpr bool is_trivially_destructible_v =
2878  is_trivially_destructible<_Tp>::value;
2879 template <typename _Tp, typename... _Args>
2880  inline constexpr bool is_nothrow_constructible_v =
2881  is_nothrow_constructible<_Tp, _Args...>::value;
2882 template <typename _Tp>
2883  inline constexpr bool is_nothrow_default_constructible_v =
2884  is_nothrow_default_constructible<_Tp>::value;
2885 template <typename _Tp>
2886  inline constexpr bool is_nothrow_copy_constructible_v =
2887  is_nothrow_copy_constructible<_Tp>::value;
2888 template <typename _Tp>
2889  inline constexpr bool is_nothrow_move_constructible_v =
2890  is_nothrow_move_constructible<_Tp>::value;
2891 template <typename _Tp, typename _Up>
2892  inline constexpr bool is_nothrow_assignable_v =
2893  is_nothrow_assignable<_Tp, _Up>::value;
2894 template <typename _Tp>
2895  inline constexpr bool is_nothrow_copy_assignable_v =
2896  is_nothrow_copy_assignable<_Tp>::value;
2897 template <typename _Tp>
2898  inline constexpr bool is_nothrow_move_assignable_v =
2899  is_nothrow_move_assignable<_Tp>::value;
2900 template <typename _Tp>
2901  inline constexpr bool is_nothrow_destructible_v =
2902  is_nothrow_destructible<_Tp>::value;
2903 template <typename _Tp>
2904  inline constexpr bool has_virtual_destructor_v =
2905  has_virtual_destructor<_Tp>::value;
2906 template <typename _Tp>
2907  inline constexpr size_t alignment_of_v = alignment_of<_Tp>::value;
2908 template <typename _Tp>
2909  inline constexpr size_t rank_v = rank<_Tp>::value;
2910 template <typename _Tp, unsigned _Idx = 0>
2911  inline constexpr size_t extent_v = extent<_Tp, _Idx>::value;
2912 template <typename _Tp, typename _Up>
2913  inline constexpr bool is_same_v = is_same<_Tp, _Up>::value;
2914 template <typename _Base, typename _Derived>
2915  inline constexpr bool is_base_of_v = is_base_of<_Base, _Derived>::value;
2916 template <typename _From, typename _To>
2917  inline constexpr bool is_convertible_v = is_convertible<_From, _To>::value;
2918 
2919 #if __GNUC__ >= 7
2920 # define _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP 1
2921 #elif defined(__is_identifier)
2922 // For non-GNU compilers:
2923 # if ! __is_identifier(__has_unique_object_representations)
2924 # define _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP 1
2925 # endif
2926 #endif
2927 
2928 #ifdef _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP
2929 # define __cpp_lib_has_unique_object_representations 201606
2930  /// has_unique_object_representations
2931  template<typename _Tp>
2932  struct has_unique_object_representations
2933  : bool_constant<__has_unique_object_representations(
2934  remove_cv_t<remove_all_extents_t<_Tp>>
2935  )>
2936  { };
2937 
2938  template<typename _Tp>
2939  inline constexpr bool has_unique_object_representations_v
2940  = has_unique_object_representations<_Tp>::value;
2941 #endif
2942 #undef _GLIBCXX_HAVE_BUILTIN_HAS_UNIQ_OBJ_REP
2943 
2944 #if __GNUC__ >= 7
2945 # define _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE 1
2946 #elif defined(__is_identifier)
2947 // For non-GNU compilers:
2948 # if ! __is_identifier(__is_aggregate)
2949 # define _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE 1
2950 # endif
2951 #endif
2952 
2953 #ifdef _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE
2954 #define __cpp_lib_is_aggregate 201703
2955  /// is_aggregate
2956  template<typename _Tp>
2957  struct is_aggregate
2958  : bool_constant<__is_aggregate(remove_cv_t<_Tp>)> { };
2959 
2960  /// is_aggregate_v
2961  template<typename _Tp>
2962  inline constexpr bool is_aggregate_v = is_aggregate<_Tp>::value;
2963 #endif
2964 #undef _GLIBCXX_HAVE_BUILTIN_IS_AGGREGATE
2965 
2966 #endif // C++17
2967 
2968 #if __cplusplus > 201703L
2969  /// Byte order
2970  enum class endian
2971  {
2972  little = __ORDER_LITTLE_ENDIAN__,
2973  big = __ORDER_BIG_ENDIAN__,
2974  native = __BYTE_ORDER__
2975  };
2976 #endif // C++2a
2977 
2978 _GLIBCXX_END_NAMESPACE_VERSION
2979 } // namespace std
2980 
2981 #endif // C++11
2982 
2983 #endif // _GLIBCXX_TYPE_TRAITS
std::is_assignable
is_assignable
Definition: type_traits:1048
std::remove_all_extents
remove_all_extents
Definition: type_traits:762
std::is_same
is_same
Definition: type_traits:1328
std::remove_extent
remove_extent
Definition: type_traits:1745
std::add_volatile
add_volatile
Definition: type_traits:1409
std::is_rvalue_reference
is_rvalue_reference
Definition: type_traits:383
std::is_trivially_assignable
is_trivially_assignable
Definition: type_traits:1223
std::is_move_assignable
is_move_assignable
Definition: type_traits:1084
std::remove_volatile_t
typename remove_volatile< _Tp >::type remove_volatile_t
Alias template for remove_volatile.
Definition: type_traits:1430
std::remove_volatile
remove_volatile
Definition: type_traits:1387
std::is_pointer
is_pointer
Definition: type_traits:368
std::is_convertible
is_convertible
Definition: type_traits:1369
std::add_const_t
typename add_const< _Tp >::type add_const_t
Alias template for add_const.
Definition: type_traits:1438
std::common_type
common_type
Definition: type_traits:1979
std::underlying_type_t
typename underlying_type< _Tp >::type underlying_type_t
Alias template for underlying_type.
Definition: type_traits:2348
std::is_standard_layout
is_standard_layout
Definition: type_traits:673
std::is_member_function_pointer
is_member_function_pointer
Definition: type_traits:418
std::is_nothrow_constructible
is_nothrow_constructible
Definition: type_traits:1005
std::is_nothrow_destructible
is_nothrow_destructible
Definition: type_traits:866
std::conditional_t
typename conditional< _Cond, _Iftrue, _Iffalse >::type conditional_t
Alias template for conditional.
Definition: type_traits:2340
std::remove_all_extents_t
typename remove_all_extents< _Tp >::type remove_all_extents_t
Alias template for remove_all_extents.
Definition: type_traits:1776
std::is_member_object_pointer
is_member_object_pointer
Definition: type_traits:403
std::__is_trivially_move_assignable_impl
is_trivially_move_assignable
Definition: type_traits:1251
std::underlying_type
The underlying type of an enum.
Definition: type_traits:2049
std::void_t
void void_t
A metafunction that always yields void, used for detecting valid types.
Definition: type_traits:2365
std::conditional
Define a member typedef type to one of two argument types.
Definition: type_traits:92
std::add_rvalue_reference_t
typename add_rvalue_reference< _Tp >::type add_rvalue_reference_t
Alias template for add_rvalue_reference.
Definition: type_traits:1503
std::remove_reference
remove_reference
Definition: type_traits:1453
std::make_unsigned
make_unsigned
Definition: type_traits:1635
std::is_const
is_const
Definition: type_traits:643
std::is_function
is_function
Definition: type_traits:391
std::is_swappable
Metafunctions used for detecting swappable types: p0185r1.
Definition: type_traits:2508
std::is_nothrow_assignable
is_nothrow_assignable
Definition: type_traits:1095
std::false_type
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:78
std::aligned_storage
Alignment type.
Definition: type_traits:1842
std::add_const
add_const
Definition: type_traits:1404
std::is_final
is_final
Definition: type_traits:706
std::is_null_pointer
is_null_pointer (LWG 2247).
Definition: type_traits:554
std::add_volatile_t
typename add_volatile< _Tp >::type add_volatile_t
Alias template for add_volatile.
Definition: type_traits:1442
std::add_rvalue_reference
add_rvalue_reference
Definition: type_traits:1488
std::is_literal_type
is_literal_type
Definition: type_traits:686
std::is_union
is_union
Definition: type_traits:431
std::is_swappable_with
is_swappable_with
Definition: type_traits:2592
std::has_virtual_destructor
has_virtual_destructor
Definition: type_traits:1279
std::is_nothrow_move_assignable
is_nothrow_move_assignable
Definition: type_traits:1132
std::is_nothrow_swappable_v
_GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_v
is_nothrow_swappable_v
Definition: type_traits:2526
std::add_lvalue_reference
add_lvalue_reference
Definition: type_traits:1474
std::add_lvalue_reference_t
typename add_lvalue_reference< _Tp >::type add_lvalue_reference_t
Alias template for add_lvalue_reference.
Definition: type_traits:1499
std::common_type_t
typename common_type< _Tp... >::type common_type_t
Alias template for common_type.
Definition: type_traits:2344
std::is_reference
is_reference
Definition: type_traits:568
std::is_default_constructible
is_default_constructible
Definition: type_traits:914
std::is_polymorphic
is_polymorphic
Definition: type_traits:698
std::is_trivially_default_constructible
is_trivially_default_constructible
Definition: type_traits:1145
std::is_nothrow_copy_constructible
is_nothrow_copy_constructible
Definition: type_traits:1024
std::reference_wrapper
Primary class template for reference_wrapper.
Definition: type_traits:1929
std::make_signed_t
typename make_signed< _Tp >::type make_signed_t
Alias template for make_signed.
Definition: type_traits:1734
std::aligned_storage_t
typename aligned_storage< _Len, _Align >::type aligned_storage_t
Alias template for aligned_storage.
Definition: type_traits:2325
std::true_type
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:75
std::remove_pointer_t
typename remove_pointer< _Tp >::type remove_pointer_t
Alias template for remove_pointer.
Definition: type_traits:1813
std::is_member_pointer
is_member_pointer
Definition: type_traits:594
std
ISO C++ entities toplevel namespace is std.
std::is_void
is_void
Definition: type_traits:202
std::decay_t
typename decay< _Tp >::type decay_t
Alias template for decay.
Definition: type_traits:2332
std::aligned_union::type
aligned_storage< _S_len, alignment_value >::type type
The storage.
Definition: type_traits:1892
std::is_base_of
is_base_of
Definition: type_traits:1337
std::is_arithmetic
is_arithmetic
Definition: type_traits:575
std::is_floating_point
is_floating_point
Definition: type_traits:341
std::remove_cv
remove_cv
Definition: type_traits:190
std::__detector
Implementation of the detection idiom (negative case).
Definition: type_traits:2371
std::is_nothrow_move_constructible
is_nothrow_move_constructible
Definition: type_traits:1042
std::enable_if
Define a member typedef type only if a boolean constant is true.
Definition: type_traits:1955
std::is_constructible
is_constructible
Definition: type_traits:920
std::extent
extent
Definition: type_traits:759
std::remove_extent_t
typename remove_extent< _Tp >::type remove_extent_t
Alias template for remove_extent.
Definition: type_traits:1772
std::make_unsigned_t
typename make_unsigned< _Tp >::type make_unsigned_t
Alias template for make_unsigned.
Definition: type_traits:1738
std::add_pointer_t
typename add_pointer< _Tp >::type add_pointer_t
Alias template for add_pointer.
Definition: type_traits:1817
std::result_of
result_of
Definition: type_traits:2123
std::make_signed
make_signed
Definition: type_traits:1724
std::remove_reference_t
typename remove_reference< _Tp >::type remove_reference_t
Alias template for remove_reference.
Definition: type_traits:1495
std::is_move_constructible
is_move_constructible
Definition: type_traits:956
std::is_compound
is_compound
Definition: type_traits:605
std::remove_const_t
typename remove_const< _Tp >::type remove_const_t
Alias template for remove_const.
Definition: type_traits:1426
std::__is_trivially_move_constructible_impl
is_trivially_move_constructible
Definition: type_traits:1203
std::is_copy_assignable
is_copy_assignable
Definition: type_traits:1066
std::remove_pointer
remove_pointer
Definition: type_traits:1791
std::enable_if_t
typename enable_if< _Cond, _Tp >::type enable_if_t
Alias template for enable_if.
Definition: type_traits:2336
std::result_of_t
typename result_of< _Tp >::type result_of_t
Alias template for result_of.
Definition: type_traits:2352
std::is_volatile
is_volatile
Definition: type_traits:652
std::is_nothrow_default_constructible
is_nothrow_default_constructible
Definition: type_traits:982
std::integral_constant
integral_constant
Definition: type_traits:57
std::add_cv
add_cv
Definition: type_traits:1414
std::add_cv_t
typename add_cv< _Tp >::type add_cv_t
Alias template for add_cv.
Definition: type_traits:1446
std::__is_trivially_copy_assignable_impl
is_trivially_copy_assignable
Definition: type_traits:1230
std::is_destructible
is_destructible
Definition: type_traits:818
std::is_nothrow_swappable_with_v
_GLIBCXX17_INLINE constexpr bool is_nothrow_swappable_with_v
is_nothrow_swappable_with_v
Definition: type_traits:2610
std::is_pod
is_pod
Definition: type_traits:680
std::is_swappable_with_v
_GLIBCXX17_INLINE constexpr bool is_swappable_with_v
is_swappable_with_v
Definition: type_traits:2605
std::is_enum
is_enum
Definition: type_traits:425
std::is_trivially_destructible
is_trivially_destructible
Definition: type_traits:1271
std::is_object
is_object
Definition: type_traits:588
std::is_trivial
is_trivial
Definition: type_traits:661
std::is_nothrow_copy_assignable
is_nothrow_copy_assignable
Definition: type_traits:1114
std::aligned_union
Provide aligned storage for types.
Definition: type_traits:1880
std::is_nothrow_swappable
is_nothrow_swappable
Definition: type_traits:2514
std::is_swappable_v
_GLIBCXX17_INLINE constexpr bool is_swappable_v
is_swappable_v
Definition: type_traits:2521
std::is_abstract
is_abstract
Definition: type_traits:713
std::__is_nullptr_t
__is_nullptr_t (extension).
Definition: type_traits:560
std::is_lvalue_reference
is_lvalue_reference
Definition: type_traits:374
std::is_empty
is_empty
Definition: type_traits:692
std::is_class
is_class
Definition: type_traits:437
std::remove_const
remove_const
Definition: type_traits:1378
std::is_integral
is_integral
Definition: type_traits:313
std::is_nothrow_swappable_with
is_nothrow_swappable_with
Definition: type_traits:2598
std::alignment_of
alignment_of
Definition: type_traits:1288
std::is_scalar
is_scalar
Definition: type_traits:598
std::remove_cv_t
typename remove_cv< _Tp >::type remove_cv_t
Alias template for remove_cv.
Definition: type_traits:1434
std::is_trivially_constructible
is_trivially_constructible
Definition: type_traits:1138
std::is_copy_constructible
is_copy_constructible
Definition: type_traits:938
std::is_fundamental
is_fundamental
Definition: type_traits:581
std::is_array
is_array
Definition: type_traits:347
std::__is_trivially_copy_constructible_impl
is_trivially_copy_constructible
Definition: type_traits:1182