functional revision 288943
1// -*- C++ -*-
2//===------------------------ functional ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_FUNCTIONAL
12#define _LIBCPP_FUNCTIONAL
13
14/*
15    functional synopsis
16
17namespace std
18{
19
20template <class Arg, class Result>
21struct unary_function
22{
23    typedef Arg    argument_type;
24    typedef Result result_type;
25};
26
27template <class Arg1, class Arg2, class Result>
28struct binary_function
29{
30    typedef Arg1   first_argument_type;
31    typedef Arg2   second_argument_type;
32    typedef Result result_type;
33};
34
35template <class T>
36class reference_wrapper
37    : public unary_function<T1, R> // if wrapping a unary functor
38    : public binary_function<T1, T2, R> // if wraping a binary functor
39{
40public:
41    // types
42    typedef T type;
43    typedef see below result_type; // Not always defined
44
45    // construct/copy/destroy
46    reference_wrapper(T&) noexcept;
47    reference_wrapper(T&&) = delete; // do not bind to temps
48    reference_wrapper(const reference_wrapper<T>& x) noexcept;
49
50    // assignment
51    reference_wrapper& operator=(const reference_wrapper<T>& x) noexcept;
52
53    // access
54    operator T& () const noexcept;
55    T& get() const noexcept;
56
57    // invoke
58    template <class... ArgTypes>
59      typename result_of<T&(ArgTypes&&...)>::type
60          operator() (ArgTypes&&...) const;
61};
62
63template <class T> reference_wrapper<T> ref(T& t) noexcept;
64template <class T> void ref(const T&& t) = delete;
65template <class T> reference_wrapper<T> ref(reference_wrapper<T>t) noexcept;
66
67template <class T> reference_wrapper<const T> cref(const T& t) noexcept;
68template <class T> void cref(const T&& t) = delete;
69template <class T> reference_wrapper<const T> cref(reference_wrapper<T> t) noexcept;
70
71template <class T> // <class T=void> in C++14
72struct plus : binary_function<T, T, T>
73{
74    T operator()(const T& x, const T& y) const;
75};
76
77template <class T> // <class T=void> in C++14
78struct minus : binary_function<T, T, T>
79{
80    T operator()(const T& x, const T& y) const;
81};
82
83template <class T> // <class T=void> in C++14
84struct multiplies : binary_function<T, T, T>
85{
86    T operator()(const T& x, const T& y) const;
87};
88
89template <class T> // <class T=void> in C++14
90struct divides : binary_function<T, T, T>
91{
92    T operator()(const T& x, const T& y) const;
93};
94
95template <class T> // <class T=void> in C++14
96struct modulus : binary_function<T, T, T>
97{
98    T operator()(const T& x, const T& y) const;
99};
100
101template <class T> // <class T=void> in C++14
102struct negate : unary_function<T, T>
103{
104    T operator()(const T& x) const;
105};
106
107template <class T> // <class T=void> in C++14
108struct equal_to : binary_function<T, T, bool>
109{
110    bool operator()(const T& x, const T& y) const;
111};
112
113template <class T> // <class T=void> in C++14
114struct not_equal_to : binary_function<T, T, bool>
115{
116    bool operator()(const T& x, const T& y) const;
117};
118
119template <class T> // <class T=void> in C++14
120struct greater : binary_function<T, T, bool>
121{
122    bool operator()(const T& x, const T& y) const;
123};
124
125template <class T> // <class T=void> in C++14
126struct less : binary_function<T, T, bool>
127{
128    bool operator()(const T& x, const T& y) const;
129};
130
131template <class T> // <class T=void> in C++14
132struct greater_equal : binary_function<T, T, bool>
133{
134    bool operator()(const T& x, const T& y) const;
135};
136
137template <class T> // <class T=void> in C++14
138struct less_equal : binary_function<T, T, bool>
139{
140    bool operator()(const T& x, const T& y) const;
141};
142
143template <class T> // <class T=void> in C++14
144struct logical_and : binary_function<T, T, bool>
145{
146    bool operator()(const T& x, const T& y) const;
147};
148
149template <class T> // <class T=void> in C++14
150struct logical_or : binary_function<T, T, bool>
151{
152    bool operator()(const T& x, const T& y) const;
153};
154
155template <class T> // <class T=void> in C++14
156struct logical_not : unary_function<T, bool>
157{
158    bool operator()(const T& x) const;
159};
160
161template <class T> // <class T=void> in C++14
162struct bit_and : unary_function<T, bool>
163{
164    bool operator()(const T& x, const T& y) const;
165};
166
167template <class T> // <class T=void> in C++14
168struct bit_or : unary_function<T, bool>
169{
170    bool operator()(const T& x, const T& y) const;
171};
172
173template <class T> // <class T=void> in C++14
174struct bit_xor : unary_function<T, bool>
175{
176    bool operator()(const T& x, const T& y) const;
177};
178
179template <class T=void> // C++14
180struct bit_xor : unary_function<T, bool>
181{
182    bool operator()(const T& x) const;
183};
184
185template <class Predicate>
186class unary_negate
187    : public unary_function<typename Predicate::argument_type, bool>
188{
189public:
190    explicit unary_negate(const Predicate& pred);
191    bool operator()(const typename Predicate::argument_type& x) const;
192};
193
194template <class Predicate> unary_negate<Predicate> not1(const Predicate& pred);
195
196template <class Predicate>
197class binary_negate
198    : public binary_function<typename Predicate::first_argument_type,
199                             typename Predicate::second_argument_type,
200                             bool>
201{
202public:
203    explicit binary_negate(const Predicate& pred);
204    bool operator()(const typename Predicate::first_argument_type& x,
205                    const typename Predicate::second_argument_type& y) const;
206};
207
208template <class Predicate> binary_negate<Predicate> not2(const Predicate& pred);
209
210template<class T> struct is_bind_expression;
211template<class T> struct is_placeholder;
212
213template<class Fn, class... BoundArgs>
214  unspecified bind(Fn&&, BoundArgs&&...);
215template<class R, class Fn, class... BoundArgs>
216  unspecified bind(Fn&&, BoundArgs&&...);
217
218namespace placeholders {
219  // M is the implementation-defined number of placeholders
220  extern unspecified _1;
221  extern unspecified _2;
222  .
223  .
224  .
225  extern unspecified _Mp;
226}
227
228template <class Operation>
229class binder1st
230    : public unary_function<typename Operation::second_argument_type,
231                            typename Operation::result_type>
232{
233protected:
234    Operation                               op;
235    typename Operation::first_argument_type value;
236public:
237    binder1st(const Operation& x, const typename Operation::first_argument_type y);
238    typename Operation::result_type operator()(      typename Operation::second_argument_type& x) const;
239    typename Operation::result_type operator()(const typename Operation::second_argument_type& x) const;
240};
241
242template <class Operation, class T>
243binder1st<Operation> bind1st(const Operation& op, const T& x);
244
245template <class Operation>
246class binder2nd
247    : public unary_function<typename Operation::first_argument_type,
248                            typename Operation::result_type>
249{
250protected:
251    Operation                                op;
252    typename Operation::second_argument_type value;
253public:
254    binder2nd(const Operation& x, const typename Operation::second_argument_type y);
255    typename Operation::result_type operator()(      typename Operation::first_argument_type& x) const;
256    typename Operation::result_type operator()(const typename Operation::first_argument_type& x) const;
257};
258
259template <class Operation, class T>
260binder2nd<Operation> bind2nd(const Operation& op, const T& x);
261
262template <class Arg, class Result>
263class pointer_to_unary_function : public unary_function<Arg, Result>
264{
265public:
266    explicit pointer_to_unary_function(Result (*f)(Arg));
267    Result operator()(Arg x) const;
268};
269
270template <class Arg, class Result>
271pointer_to_unary_function<Arg,Result> ptr_fun(Result (*f)(Arg));
272
273template <class Arg1, class Arg2, class Result>
274class pointer_to_binary_function : public binary_function<Arg1, Arg2, Result>
275{
276public:
277    explicit pointer_to_binary_function(Result (*f)(Arg1, Arg2));
278    Result operator()(Arg1 x, Arg2 y) const;
279};
280
281template <class Arg1, class Arg2, class Result>
282pointer_to_binary_function<Arg1,Arg2,Result> ptr_fun(Result (*f)(Arg1,Arg2));
283
284template<class S, class T>
285class mem_fun_t : public unary_function<T*, S>
286{
287public:
288    explicit mem_fun_t(S (T::*p)());
289    S operator()(T* p) const;
290};
291
292template<class S, class T, class A>
293class mem_fun1_t : public binary_function<T*, A, S>
294{
295public:
296    explicit mem_fun1_t(S (T::*p)(A));
297    S operator()(T* p, A x) const;
298};
299
300template<class S, class T>          mem_fun_t<S,T>    mem_fun(S (T::*f)());
301template<class S, class T, class A> mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A));
302
303template<class S, class T>
304class mem_fun_ref_t : public unary_function<T, S>
305{
306public:
307    explicit mem_fun_ref_t(S (T::*p)());
308    S operator()(T& p) const;
309};
310
311template<class S, class T, class A>
312class mem_fun1_ref_t : public binary_function<T, A, S>
313{
314public:
315    explicit mem_fun1_ref_t(S (T::*p)(A));
316    S operator()(T& p, A x) const;
317};
318
319template<class S, class T>          mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)());
320template<class S, class T, class A> mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A));
321
322template <class S, class T>
323class const_mem_fun_t : public unary_function<const T*, S>
324{
325public:
326    explicit const_mem_fun_t(S (T::*p)() const);
327    S operator()(const T* p) const;
328};
329
330template <class S, class T, class A>
331class const_mem_fun1_t : public binary_function<const T*, A, S>
332{
333public:
334    explicit const_mem_fun1_t(S (T::*p)(A) const);
335    S operator()(const T* p, A x) const;
336};
337
338template <class S, class T>          const_mem_fun_t<S,T>    mem_fun(S (T::*f)() const);
339template <class S, class T, class A> const_mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A) const);
340
341template <class S, class T>
342class const_mem_fun_ref_t : public unary_function<T, S>
343{
344public:
345    explicit const_mem_fun_ref_t(S (T::*p)() const);
346    S operator()(const T& p) const;
347};
348
349template <class S, class T, class A>
350class const_mem_fun1_ref_t : public binary_function<T, A, S>
351{
352public:
353    explicit const_mem_fun1_ref_t(S (T::*p)(A) const);
354    S operator()(const T& p, A x) const;
355};
356
357template <class S, class T>          const_mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)() const);
358template <class S, class T, class A> const_mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A) const);
359
360template<class R, class T> unspecified mem_fn(R T::*);
361
362class bad_function_call
363    : public exception
364{
365};
366
367template<class> class function; // undefined
368
369template<class R, class... ArgTypes>
370class function<R(ArgTypes...)>
371  : public unary_function<T1, R>      // iff sizeof...(ArgTypes) == 1 and
372                                      // ArgTypes contains T1
373  : public binary_function<T1, T2, R> // iff sizeof...(ArgTypes) == 2 and
374                                      // ArgTypes contains T1 and T2
375{
376public:
377    typedef R result_type;
378
379    // construct/copy/destroy:
380    function() noexcept;
381    function(nullptr_t) noexcept;
382    function(const function&);
383    function(function&&) noexcept;
384    template<class F>
385      function(F);
386    template<Allocator Alloc>
387      function(allocator_arg_t, const Alloc&) noexcept;
388    template<Allocator Alloc>
389      function(allocator_arg_t, const Alloc&, nullptr_t) noexcept;
390    template<Allocator Alloc>
391      function(allocator_arg_t, const Alloc&, const function&);
392    template<Allocator Alloc>
393      function(allocator_arg_t, const Alloc&, function&&);
394    template<class F, Allocator Alloc>
395      function(allocator_arg_t, const Alloc&, F);
396
397    function& operator=(const function&);
398    function& operator=(function&&) noexcept;
399    function& operator=(nullptr_t) noexcept;
400    template<class F>
401      function& operator=(F&&);
402    template<class F>
403      function& operator=(reference_wrapper<F>) noexcept;
404
405    ~function();
406
407    // function modifiers:
408    void swap(function&) noexcept;
409    template<class F, class Alloc>
410      void assign(F&&, const Alloc&);
411
412    // function capacity:
413    explicit operator bool() const noexcept;
414
415    // function invocation:
416    R operator()(ArgTypes...) const;
417
418    // function target access:
419    const std::type_info& target_type() const noexcept;
420    template <typename T>       T* target() noexcept;
421    template <typename T> const T* target() const noexcept;
422};
423
424// Null pointer comparisons:
425template <class R, class ... ArgTypes>
426  bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
427
428template <class R, class ... ArgTypes>
429  bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
430
431template <class R, class ... ArgTypes>
432  bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
433
434template <class  R, class ... ArgTypes>
435  bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
436
437// specialized algorithms:
438template <class  R, class ... ArgTypes>
439  void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&) noexcept;
440
441template <class T> struct hash;
442
443template <> struct hash<bool>;
444template <> struct hash<char>;
445template <> struct hash<signed char>;
446template <> struct hash<unsigned char>;
447template <> struct hash<char16_t>;
448template <> struct hash<char32_t>;
449template <> struct hash<wchar_t>;
450template <> struct hash<short>;
451template <> struct hash<unsigned short>;
452template <> struct hash<int>;
453template <> struct hash<unsigned int>;
454template <> struct hash<long>;
455template <> struct hash<long long>;
456template <> struct hash<unsigned long>;
457template <> struct hash<unsigned long long>;
458
459template <> struct hash<float>;
460template <> struct hash<double>;
461template <> struct hash<long double>;
462
463template<class T> struct hash<T*>;
464
465}  // std
466
467POLICY:  For non-variadic implementations, the number of arguments is limited
468         to 3.  It is hoped that the need for non-variadic implementations
469         will be minimal.
470
471*/
472
473#include <__config>
474#include <type_traits>
475#include <typeinfo>
476#include <exception>
477#include <memory>
478#include <tuple>
479
480#include <__functional_base>
481
482#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
483#pragma GCC system_header
484#endif
485
486_LIBCPP_BEGIN_NAMESPACE_STD
487
488#if _LIBCPP_STD_VER > 11
489template <class _Tp = void>
490#else
491template <class _Tp>
492#endif
493struct _LIBCPP_TYPE_VIS_ONLY plus : binary_function<_Tp, _Tp, _Tp>
494{
495    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
496    _Tp operator()(const _Tp& __x, const _Tp& __y) const
497        {return __x + __y;}
498};
499
500#if _LIBCPP_STD_VER > 11
501template <>
502struct _LIBCPP_TYPE_VIS_ONLY plus<void>
503{
504    template <class _T1, class _T2>
505    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
506    auto operator()(_T1&& __t, _T2&& __u) const
507    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u)))
508    -> decltype        (_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u))
509        { return        _VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u); }
510    typedef void is_transparent;
511};
512#endif
513
514
515#if _LIBCPP_STD_VER > 11
516template <class _Tp = void>
517#else
518template <class _Tp>
519#endif
520struct _LIBCPP_TYPE_VIS_ONLY minus : binary_function<_Tp, _Tp, _Tp>
521{
522    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
523    _Tp operator()(const _Tp& __x, const _Tp& __y) const
524        {return __x - __y;}
525};
526
527#if _LIBCPP_STD_VER > 11
528template <>
529struct _LIBCPP_TYPE_VIS_ONLY minus<void>
530{
531    template <class _T1, class _T2>
532    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
533    auto operator()(_T1&& __t, _T2&& __u) const
534    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u)))
535    -> decltype        (_VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u))
536        { return        _VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u); }
537    typedef void is_transparent;
538};
539#endif
540
541
542#if _LIBCPP_STD_VER > 11
543template <class _Tp = void>
544#else
545template <class _Tp>
546#endif
547struct _LIBCPP_TYPE_VIS_ONLY multiplies : binary_function<_Tp, _Tp, _Tp>
548{
549    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
550    _Tp operator()(const _Tp& __x, const _Tp& __y) const
551        {return __x * __y;}
552};
553
554#if _LIBCPP_STD_VER > 11
555template <>
556struct _LIBCPP_TYPE_VIS_ONLY multiplies<void>
557{
558    template <class _T1, class _T2>
559    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
560    auto operator()(_T1&& __t, _T2&& __u) const
561    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u)))
562    -> decltype        (_VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u))
563        { return        _VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u); }
564    typedef void is_transparent;
565};
566#endif
567
568
569#if _LIBCPP_STD_VER > 11
570template <class _Tp = void>
571#else
572template <class _Tp>
573#endif
574struct _LIBCPP_TYPE_VIS_ONLY divides : binary_function<_Tp, _Tp, _Tp>
575{
576    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
577    _Tp operator()(const _Tp& __x, const _Tp& __y) const
578        {return __x / __y;}
579};
580
581#if _LIBCPP_STD_VER > 11
582template <>
583struct _LIBCPP_TYPE_VIS_ONLY divides<void>
584{
585    template <class _T1, class _T2>
586    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
587    auto operator()(_T1&& __t, _T2&& __u) const
588    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u)))
589    -> decltype        (_VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u))
590        { return        _VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u); }
591    typedef void is_transparent;
592};
593#endif
594
595
596#if _LIBCPP_STD_VER > 11
597template <class _Tp = void>
598#else
599template <class _Tp>
600#endif
601struct _LIBCPP_TYPE_VIS_ONLY modulus : binary_function<_Tp, _Tp, _Tp>
602{
603    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
604    _Tp operator()(const _Tp& __x, const _Tp& __y) const
605        {return __x % __y;}
606};
607
608#if _LIBCPP_STD_VER > 11
609template <>
610struct _LIBCPP_TYPE_VIS_ONLY modulus<void>
611{
612    template <class _T1, class _T2>
613    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
614    auto operator()(_T1&& __t, _T2&& __u) const
615    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u)))
616    -> decltype        (_VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u))
617        { return        _VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u); }
618    typedef void is_transparent;
619};
620#endif
621
622
623#if _LIBCPP_STD_VER > 11
624template <class _Tp = void>
625#else
626template <class _Tp>
627#endif
628struct _LIBCPP_TYPE_VIS_ONLY negate : unary_function<_Tp, _Tp>
629{
630    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
631    _Tp operator()(const _Tp& __x) const
632        {return -__x;}
633};
634
635#if _LIBCPP_STD_VER > 11
636template <>
637struct _LIBCPP_TYPE_VIS_ONLY negate<void>
638{
639    template <class _Tp>
640    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
641    auto operator()(_Tp&& __x) const
642    _NOEXCEPT_(noexcept(- _VSTD::forward<_Tp>(__x)))
643    -> decltype        (- _VSTD::forward<_Tp>(__x))
644        { return        - _VSTD::forward<_Tp>(__x); }
645    typedef void is_transparent;
646};
647#endif
648
649
650#if _LIBCPP_STD_VER > 11
651template <class _Tp = void>
652#else
653template <class _Tp>
654#endif
655struct _LIBCPP_TYPE_VIS_ONLY equal_to : binary_function<_Tp, _Tp, bool>
656{
657    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
658    bool operator()(const _Tp& __x, const _Tp& __y) const
659        {return __x == __y;}
660};
661
662#if _LIBCPP_STD_VER > 11
663template <>
664struct _LIBCPP_TYPE_VIS_ONLY equal_to<void>
665{
666    template <class _T1, class _T2>
667    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
668    auto operator()(_T1&& __t, _T2&& __u) const
669    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u)))
670    -> decltype        (_VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u))
671        { return        _VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u); }
672    typedef void is_transparent;
673};
674#endif
675
676
677#if _LIBCPP_STD_VER > 11
678template <class _Tp = void>
679#else
680template <class _Tp>
681#endif
682struct _LIBCPP_TYPE_VIS_ONLY not_equal_to : binary_function<_Tp, _Tp, bool>
683{
684    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
685    bool operator()(const _Tp& __x, const _Tp& __y) const
686        {return __x != __y;}
687};
688
689#if _LIBCPP_STD_VER > 11
690template <>
691struct _LIBCPP_TYPE_VIS_ONLY not_equal_to<void>
692{
693    template <class _T1, class _T2>
694    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
695    auto operator()(_T1&& __t, _T2&& __u) const
696    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u)))
697    -> decltype        (_VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u))
698        { return        _VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u); }
699    typedef void is_transparent;
700};
701#endif
702
703
704#if _LIBCPP_STD_VER > 11
705template <class _Tp = void>
706#else
707template <class _Tp>
708#endif
709struct _LIBCPP_TYPE_VIS_ONLY greater : binary_function<_Tp, _Tp, bool>
710{
711    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
712    bool operator()(const _Tp& __x, const _Tp& __y) const
713        {return __x > __y;}
714};
715
716#if _LIBCPP_STD_VER > 11
717template <>
718struct _LIBCPP_TYPE_VIS_ONLY greater<void>
719{
720    template <class _T1, class _T2>
721    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
722    auto operator()(_T1&& __t, _T2&& __u) const
723    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u)))
724    -> decltype        (_VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u))
725        { return        _VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u); }
726    typedef void is_transparent;
727};
728#endif
729
730
731// less in <__functional_base>
732
733#if _LIBCPP_STD_VER > 11
734template <class _Tp = void>
735#else
736template <class _Tp>
737#endif
738struct _LIBCPP_TYPE_VIS_ONLY greater_equal : binary_function<_Tp, _Tp, bool>
739{
740    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
741    bool operator()(const _Tp& __x, const _Tp& __y) const
742        {return __x >= __y;}
743};
744
745#if _LIBCPP_STD_VER > 11
746template <>
747struct _LIBCPP_TYPE_VIS_ONLY greater_equal<void>
748{
749    template <class _T1, class _T2>
750    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
751    auto operator()(_T1&& __t, _T2&& __u) const
752    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u)))
753    -> decltype        (_VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u))
754        { return        _VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u); }
755    typedef void is_transparent;
756};
757#endif
758
759
760#if _LIBCPP_STD_VER > 11
761template <class _Tp = void>
762#else
763template <class _Tp>
764#endif
765struct _LIBCPP_TYPE_VIS_ONLY less_equal : binary_function<_Tp, _Tp, bool>
766{
767    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
768    bool operator()(const _Tp& __x, const _Tp& __y) const
769        {return __x <= __y;}
770};
771
772#if _LIBCPP_STD_VER > 11
773template <>
774struct _LIBCPP_TYPE_VIS_ONLY less_equal<void>
775{
776    template <class _T1, class _T2>
777    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
778    auto operator()(_T1&& __t, _T2&& __u) const
779    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u)))
780    -> decltype        (_VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u))
781        { return        _VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u); }
782    typedef void is_transparent;
783};
784#endif
785
786
787#if _LIBCPP_STD_VER > 11
788template <class _Tp = void>
789#else
790template <class _Tp>
791#endif
792struct _LIBCPP_TYPE_VIS_ONLY logical_and : binary_function<_Tp, _Tp, bool>
793{
794    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
795    bool operator()(const _Tp& __x, const _Tp& __y) const
796        {return __x && __y;}
797};
798
799#if _LIBCPP_STD_VER > 11
800template <>
801struct _LIBCPP_TYPE_VIS_ONLY logical_and<void>
802{
803    template <class _T1, class _T2>
804    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
805    auto operator()(_T1&& __t, _T2&& __u) const
806    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u)))
807    -> decltype        (_VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u))
808        { return        _VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u); }
809    typedef void is_transparent;
810};
811#endif
812
813
814#if _LIBCPP_STD_VER > 11
815template <class _Tp = void>
816#else
817template <class _Tp>
818#endif
819struct _LIBCPP_TYPE_VIS_ONLY logical_or : binary_function<_Tp, _Tp, bool>
820{
821    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
822    bool operator()(const _Tp& __x, const _Tp& __y) const
823        {return __x || __y;}
824};
825
826#if _LIBCPP_STD_VER > 11
827template <>
828struct _LIBCPP_TYPE_VIS_ONLY logical_or<void>
829{
830    template <class _T1, class _T2>
831    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
832    auto operator()(_T1&& __t, _T2&& __u) const
833    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u)))
834    -> decltype        (_VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u))
835        { return        _VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u); }
836    typedef void is_transparent;
837};
838#endif
839
840
841#if _LIBCPP_STD_VER > 11
842template <class _Tp = void>
843#else
844template <class _Tp>
845#endif
846struct _LIBCPP_TYPE_VIS_ONLY logical_not : unary_function<_Tp, bool>
847{
848    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
849    bool operator()(const _Tp& __x) const
850        {return !__x;}
851};
852
853#if _LIBCPP_STD_VER > 11
854template <>
855struct _LIBCPP_TYPE_VIS_ONLY logical_not<void>
856{
857    template <class _Tp>
858    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
859    auto operator()(_Tp&& __x) const
860    _NOEXCEPT_(noexcept(!_VSTD::forward<_Tp>(__x)))
861    -> decltype        (!_VSTD::forward<_Tp>(__x))
862        { return        !_VSTD::forward<_Tp>(__x); }
863    typedef void is_transparent;
864};
865#endif
866
867
868#if _LIBCPP_STD_VER > 11
869template <class _Tp = void>
870#else
871template <class _Tp>
872#endif
873struct _LIBCPP_TYPE_VIS_ONLY bit_and : binary_function<_Tp, _Tp, _Tp>
874{
875    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
876    _Tp operator()(const _Tp& __x, const _Tp& __y) const
877        {return __x & __y;}
878};
879
880#if _LIBCPP_STD_VER > 11
881template <>
882struct _LIBCPP_TYPE_VIS_ONLY bit_and<void>
883{
884    template <class _T1, class _T2>
885    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
886    auto operator()(_T1&& __t, _T2&& __u) const
887    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u)))
888    -> decltype        (_VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u))
889        { return        _VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u); }
890    typedef void is_transparent;
891};
892#endif
893
894
895#if _LIBCPP_STD_VER > 11
896template <class _Tp = void>
897#else
898template <class _Tp>
899#endif
900struct _LIBCPP_TYPE_VIS_ONLY bit_or : binary_function<_Tp, _Tp, _Tp>
901{
902    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
903    _Tp operator()(const _Tp& __x, const _Tp& __y) const
904        {return __x | __y;}
905};
906
907#if _LIBCPP_STD_VER > 11
908template <>
909struct _LIBCPP_TYPE_VIS_ONLY bit_or<void>
910{
911    template <class _T1, class _T2>
912    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
913    auto operator()(_T1&& __t, _T2&& __u) const
914    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u)))
915    -> decltype        (_VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u))
916        { return        _VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u); }
917    typedef void is_transparent;
918};
919#endif
920
921
922#if _LIBCPP_STD_VER > 11
923template <class _Tp = void>
924#else
925template <class _Tp>
926#endif
927struct _LIBCPP_TYPE_VIS_ONLY bit_xor : binary_function<_Tp, _Tp, _Tp>
928{
929    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
930    _Tp operator()(const _Tp& __x, const _Tp& __y) const
931        {return __x ^ __y;}
932};
933
934#if _LIBCPP_STD_VER > 11
935template <>
936struct _LIBCPP_TYPE_VIS_ONLY bit_xor<void>
937{
938    template <class _T1, class _T2>
939    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
940    auto operator()(_T1&& __t, _T2&& __u) const
941    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u)))
942    -> decltype        (_VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u))
943        { return        _VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u); }
944    typedef void is_transparent;
945};
946#endif
947
948
949#if _LIBCPP_STD_VER > 11
950template <class _Tp = void>
951struct _LIBCPP_TYPE_VIS_ONLY bit_not : unary_function<_Tp, _Tp>
952{
953    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
954    _Tp operator()(const _Tp& __x) const
955        {return ~__x;}
956};
957
958template <>
959struct _LIBCPP_TYPE_VIS_ONLY bit_not<void>
960{
961    template <class _Tp>
962    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
963    auto operator()(_Tp&& __x) const
964    _NOEXCEPT_(noexcept(~_VSTD::forward<_Tp>(__x)))
965    -> decltype        (~_VSTD::forward<_Tp>(__x))
966        { return        ~_VSTD::forward<_Tp>(__x); }
967    typedef void is_transparent;
968};
969#endif
970
971template <class _Predicate>
972class _LIBCPP_TYPE_VIS_ONLY unary_negate
973    : public unary_function<typename _Predicate::argument_type, bool>
974{
975    _Predicate __pred_;
976public:
977    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
978    explicit unary_negate(const _Predicate& __pred)
979        : __pred_(__pred) {}
980    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
981    bool operator()(const typename _Predicate::argument_type& __x) const
982        {return !__pred_(__x);}
983};
984
985template <class _Predicate>
986inline _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
987unary_negate<_Predicate>
988not1(const _Predicate& __pred) {return unary_negate<_Predicate>(__pred);}
989
990template <class _Predicate>
991class _LIBCPP_TYPE_VIS_ONLY binary_negate
992    : public binary_function<typename _Predicate::first_argument_type,
993                             typename _Predicate::second_argument_type,
994                             bool>
995{
996    _Predicate __pred_;
997public:
998    _LIBCPP_INLINE_VISIBILITY explicit _LIBCPP_CONSTEXPR_AFTER_CXX11 
999    binary_negate(const _Predicate& __pred) : __pred_(__pred) {}
1000
1001    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1002    bool operator()(const typename _Predicate::first_argument_type& __x,
1003                    const typename _Predicate::second_argument_type& __y) const
1004        {return !__pred_(__x, __y);}
1005};
1006
1007template <class _Predicate>
1008inline _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1009binary_negate<_Predicate>
1010not2(const _Predicate& __pred) {return binary_negate<_Predicate>(__pred);}
1011
1012template <class __Operation>
1013class _LIBCPP_TYPE_VIS_ONLY binder1st
1014    : public unary_function<typename __Operation::second_argument_type,
1015                            typename __Operation::result_type>
1016{
1017protected:
1018    __Operation                               op;
1019    typename __Operation::first_argument_type value;
1020public:
1021    _LIBCPP_INLINE_VISIBILITY binder1st(const __Operation& __x,
1022                               const typename __Operation::first_argument_type __y)
1023        : op(__x), value(__y) {}
1024    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1025        (typename __Operation::second_argument_type& __x) const
1026            {return op(value, __x);}
1027    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1028        (const typename __Operation::second_argument_type& __x) const
1029            {return op(value, __x);}
1030};
1031
1032template <class __Operation, class _Tp>
1033inline _LIBCPP_INLINE_VISIBILITY
1034binder1st<__Operation>
1035bind1st(const __Operation& __op, const _Tp& __x)
1036    {return binder1st<__Operation>(__op, __x);}
1037
1038template <class __Operation>
1039class _LIBCPP_TYPE_VIS_ONLY binder2nd
1040    : public unary_function<typename __Operation::first_argument_type,
1041                            typename __Operation::result_type>
1042{
1043protected:
1044    __Operation                                op;
1045    typename __Operation::second_argument_type value;
1046public:
1047    _LIBCPP_INLINE_VISIBILITY
1048    binder2nd(const __Operation& __x, const typename __Operation::second_argument_type __y)
1049        : op(__x), value(__y) {}
1050    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1051        (      typename __Operation::first_argument_type& __x) const
1052            {return op(__x, value);}
1053    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1054        (const typename __Operation::first_argument_type& __x) const
1055            {return op(__x, value);}
1056};
1057
1058template <class __Operation, class _Tp>
1059inline _LIBCPP_INLINE_VISIBILITY
1060binder2nd<__Operation>
1061bind2nd(const __Operation& __op, const _Tp& __x)
1062    {return binder2nd<__Operation>(__op, __x);}
1063
1064template <class _Arg, class _Result>
1065class _LIBCPP_TYPE_VIS_ONLY pointer_to_unary_function
1066    : public unary_function<_Arg, _Result>
1067{
1068    _Result (*__f_)(_Arg);
1069public:
1070    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_unary_function(_Result (*__f)(_Arg))
1071        : __f_(__f) {}
1072    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg __x) const
1073        {return __f_(__x);}
1074};
1075
1076template <class _Arg, class _Result>
1077inline _LIBCPP_INLINE_VISIBILITY
1078pointer_to_unary_function<_Arg,_Result>
1079ptr_fun(_Result (*__f)(_Arg))
1080    {return pointer_to_unary_function<_Arg,_Result>(__f);}
1081
1082template <class _Arg1, class _Arg2, class _Result>
1083class _LIBCPP_TYPE_VIS_ONLY pointer_to_binary_function
1084    : public binary_function<_Arg1, _Arg2, _Result>
1085{
1086    _Result (*__f_)(_Arg1, _Arg2);
1087public:
1088    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_binary_function(_Result (*__f)(_Arg1, _Arg2))
1089        : __f_(__f) {}
1090    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg1 __x, _Arg2 __y) const
1091        {return __f_(__x, __y);}
1092};
1093
1094template <class _Arg1, class _Arg2, class _Result>
1095inline _LIBCPP_INLINE_VISIBILITY
1096pointer_to_binary_function<_Arg1,_Arg2,_Result>
1097ptr_fun(_Result (*__f)(_Arg1,_Arg2))
1098    {return pointer_to_binary_function<_Arg1,_Arg2,_Result>(__f);}
1099
1100template<class _Sp, class _Tp>
1101class _LIBCPP_TYPE_VIS_ONLY mem_fun_t : public unary_function<_Tp*, _Sp>
1102{
1103    _Sp (_Tp::*__p_)();
1104public:
1105    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_t(_Sp (_Tp::*__p)())
1106        : __p_(__p) {}
1107    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p) const
1108        {return (__p->*__p_)();}
1109};
1110
1111template<class _Sp, class _Tp, class _Ap>
1112class _LIBCPP_TYPE_VIS_ONLY mem_fun1_t : public binary_function<_Tp*, _Ap, _Sp>
1113{
1114    _Sp (_Tp::*__p_)(_Ap);
1115public:
1116    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_t(_Sp (_Tp::*__p)(_Ap))
1117        : __p_(__p) {}
1118    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p, _Ap __x) const
1119        {return (__p->*__p_)(__x);}
1120};
1121
1122template<class _Sp, class _Tp>
1123inline _LIBCPP_INLINE_VISIBILITY
1124mem_fun_t<_Sp,_Tp>
1125mem_fun(_Sp (_Tp::*__f)())
1126    {return mem_fun_t<_Sp,_Tp>(__f);}
1127
1128template<class _Sp, class _Tp, class _Ap>
1129inline _LIBCPP_INLINE_VISIBILITY
1130mem_fun1_t<_Sp,_Tp,_Ap>
1131mem_fun(_Sp (_Tp::*__f)(_Ap))
1132    {return mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
1133
1134template<class _Sp, class _Tp>
1135class _LIBCPP_TYPE_VIS_ONLY mem_fun_ref_t : public unary_function<_Tp, _Sp>
1136{
1137    _Sp (_Tp::*__p_)();
1138public:
1139    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_ref_t(_Sp (_Tp::*__p)())
1140        : __p_(__p) {}
1141    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p) const
1142        {return (__p.*__p_)();}
1143};
1144
1145template<class _Sp, class _Tp, class _Ap>
1146class _LIBCPP_TYPE_VIS_ONLY mem_fun1_ref_t : public binary_function<_Tp, _Ap, _Sp>
1147{
1148    _Sp (_Tp::*__p_)(_Ap);
1149public:
1150    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap))
1151        : __p_(__p) {}
1152    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p, _Ap __x) const
1153        {return (__p.*__p_)(__x);}
1154};
1155
1156template<class _Sp, class _Tp>
1157inline _LIBCPP_INLINE_VISIBILITY
1158mem_fun_ref_t<_Sp,_Tp>
1159mem_fun_ref(_Sp (_Tp::*__f)())
1160    {return mem_fun_ref_t<_Sp,_Tp>(__f);}
1161
1162template<class _Sp, class _Tp, class _Ap>
1163inline _LIBCPP_INLINE_VISIBILITY
1164mem_fun1_ref_t<_Sp,_Tp,_Ap>
1165mem_fun_ref(_Sp (_Tp::*__f)(_Ap))
1166    {return mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
1167
1168template <class _Sp, class _Tp>
1169class _LIBCPP_TYPE_VIS_ONLY const_mem_fun_t : public unary_function<const _Tp*, _Sp>
1170{
1171    _Sp (_Tp::*__p_)() const;
1172public:
1173    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_t(_Sp (_Tp::*__p)() const)
1174        : __p_(__p) {}
1175    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p) const
1176        {return (__p->*__p_)();}
1177};
1178
1179template <class _Sp, class _Tp, class _Ap>
1180class _LIBCPP_TYPE_VIS_ONLY const_mem_fun1_t : public binary_function<const _Tp*, _Ap, _Sp>
1181{
1182    _Sp (_Tp::*__p_)(_Ap) const;
1183public:
1184    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_t(_Sp (_Tp::*__p)(_Ap) const)
1185        : __p_(__p) {}
1186    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p, _Ap __x) const
1187        {return (__p->*__p_)(__x);}
1188};
1189
1190template <class _Sp, class _Tp>
1191inline _LIBCPP_INLINE_VISIBILITY
1192const_mem_fun_t<_Sp,_Tp>
1193mem_fun(_Sp (_Tp::*__f)() const)
1194    {return const_mem_fun_t<_Sp,_Tp>(__f);}
1195
1196template <class _Sp, class _Tp, class _Ap>
1197inline _LIBCPP_INLINE_VISIBILITY
1198const_mem_fun1_t<_Sp,_Tp,_Ap>
1199mem_fun(_Sp (_Tp::*__f)(_Ap) const)
1200    {return const_mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
1201
1202template <class _Sp, class _Tp>
1203class _LIBCPP_TYPE_VIS_ONLY const_mem_fun_ref_t : public unary_function<_Tp, _Sp>
1204{
1205    _Sp (_Tp::*__p_)() const;
1206public:
1207    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_ref_t(_Sp (_Tp::*__p)() const)
1208        : __p_(__p) {}
1209    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p) const
1210        {return (__p.*__p_)();}
1211};
1212
1213template <class _Sp, class _Tp, class _Ap>
1214class _LIBCPP_TYPE_VIS_ONLY const_mem_fun1_ref_t
1215    : public binary_function<_Tp, _Ap, _Sp>
1216{
1217    _Sp (_Tp::*__p_)(_Ap) const;
1218public:
1219    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap) const)
1220        : __p_(__p) {}
1221    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p, _Ap __x) const
1222        {return (__p.*__p_)(__x);}
1223};
1224
1225template <class _Sp, class _Tp>
1226inline _LIBCPP_INLINE_VISIBILITY
1227const_mem_fun_ref_t<_Sp,_Tp>
1228mem_fun_ref(_Sp (_Tp::*__f)() const)
1229    {return const_mem_fun_ref_t<_Sp,_Tp>(__f);}
1230
1231template <class _Sp, class _Tp, class _Ap>
1232inline _LIBCPP_INLINE_VISIBILITY
1233const_mem_fun1_ref_t<_Sp,_Tp,_Ap>
1234mem_fun_ref(_Sp (_Tp::*__f)(_Ap) const)
1235    {return const_mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
1236
1237#ifdef _LIBCPP_HAS_NO_VARIADICS
1238
1239#include <__functional_03>
1240
1241#else  // _LIBCPP_HAS_NO_VARIADICS
1242
1243template <class _Tp>
1244class __mem_fn
1245    : public __weak_result_type<_Tp>
1246{
1247public:
1248    // types
1249    typedef _Tp type;
1250private:
1251    type __f_;
1252
1253public:
1254    _LIBCPP_INLINE_VISIBILITY __mem_fn(type __f) : __f_(__f) {}
1255
1256    // invoke
1257    template <class... _ArgTypes>
1258       _LIBCPP_INLINE_VISIBILITY
1259       typename __invoke_return<type, _ArgTypes...>::type
1260          operator() (_ArgTypes&&... __args) const
1261          {
1262              return __invoke(__f_, _VSTD::forward<_ArgTypes>(__args)...);
1263          }
1264};
1265
1266template<class _Rp, class _Tp>
1267inline _LIBCPP_INLINE_VISIBILITY
1268__mem_fn<_Rp _Tp::*>
1269mem_fn(_Rp _Tp::* __pm)
1270{
1271    return __mem_fn<_Rp _Tp::*>(__pm);
1272}
1273
1274// bad_function_call
1275
1276class _LIBCPP_EXCEPTION_ABI bad_function_call
1277    : public exception
1278{
1279};
1280
1281template<class _Fp> class _LIBCPP_TYPE_VIS_ONLY function; // undefined
1282
1283namespace __function
1284{
1285
1286template<class _Rp, class ..._ArgTypes>
1287struct __maybe_derive_from_unary_function
1288{
1289};
1290
1291template<class _Rp, class _A1>
1292struct __maybe_derive_from_unary_function<_Rp(_A1)>
1293    : public unary_function<_A1, _Rp>
1294{
1295};
1296
1297template<class _Rp, class ..._ArgTypes>
1298struct __maybe_derive_from_binary_function
1299{
1300};
1301
1302template<class _Rp, class _A1, class _A2>
1303struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)>
1304    : public binary_function<_A1, _A2, _Rp>
1305{
1306};
1307
1308template<class _Fp> class __base;
1309
1310template<class _Rp, class ..._ArgTypes>
1311class __base<_Rp(_ArgTypes...)>
1312{
1313    __base(const __base&);
1314    __base& operator=(const __base&);
1315public:
1316    _LIBCPP_INLINE_VISIBILITY __base() {}
1317    _LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
1318    virtual __base* __clone() const = 0;
1319    virtual void __clone(__base*) const = 0;
1320    virtual void destroy() _NOEXCEPT = 0;
1321    virtual void destroy_deallocate() _NOEXCEPT = 0;
1322    virtual _Rp operator()(_ArgTypes&& ...) = 0;
1323#ifndef _LIBCPP_NO_RTTI
1324    virtual const void* target(const type_info&) const _NOEXCEPT = 0;
1325    virtual const std::type_info& target_type() const _NOEXCEPT = 0;
1326#endif  // _LIBCPP_NO_RTTI
1327};
1328
1329template<class _FD, class _Alloc, class _FB> class __func;
1330
1331template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1332class __func<_Fp, _Alloc, _Rp(_ArgTypes...)>
1333    : public  __base<_Rp(_ArgTypes...)>
1334{
1335    __compressed_pair<_Fp, _Alloc> __f_;
1336public:
1337    _LIBCPP_INLINE_VISIBILITY
1338    explicit __func(_Fp&& __f)
1339        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
1340                                    _VSTD::forward_as_tuple()) {}
1341    _LIBCPP_INLINE_VISIBILITY
1342    explicit __func(const _Fp& __f, const _Alloc& __a)
1343        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
1344                                    _VSTD::forward_as_tuple(__a)) {}
1345
1346    _LIBCPP_INLINE_VISIBILITY
1347    explicit __func(const _Fp& __f, _Alloc&& __a)
1348        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
1349                                    _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
1350
1351    _LIBCPP_INLINE_VISIBILITY
1352    explicit __func(_Fp&& __f, _Alloc&& __a)
1353        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
1354                                    _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
1355    virtual __base<_Rp(_ArgTypes...)>* __clone() const;
1356    virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
1357    virtual void destroy() _NOEXCEPT;
1358    virtual void destroy_deallocate() _NOEXCEPT;
1359    virtual _Rp operator()(_ArgTypes&& ... __arg);
1360#ifndef _LIBCPP_NO_RTTI
1361    virtual const void* target(const type_info&) const _NOEXCEPT;
1362    virtual const std::type_info& target_type() const _NOEXCEPT;
1363#endif  // _LIBCPP_NO_RTTI
1364};
1365
1366template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1367__base<_Rp(_ArgTypes...)>*
1368__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone() const
1369{
1370    typedef allocator_traits<_Alloc> __alloc_traits;
1371    typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
1372    _Ap __a(__f_.second());
1373    typedef __allocator_destructor<_Ap> _Dp;
1374    unique_ptr<__func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1375    ::new (__hold.get()) __func(__f_.first(), _Alloc(__a));
1376    return __hold.release();
1377}
1378
1379template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1380void
1381__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const
1382{
1383    ::new (__p) __func(__f_.first(), __f_.second());
1384}
1385
1386template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1387void
1388__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() _NOEXCEPT
1389{
1390    __f_.~__compressed_pair<_Fp, _Alloc>();
1391}
1392
1393template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1394void
1395__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() _NOEXCEPT
1396{
1397    typedef allocator_traits<_Alloc> __alloc_traits;
1398    typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
1399    _Ap __a(__f_.second());
1400    __f_.~__compressed_pair<_Fp, _Alloc>();
1401    __a.deallocate(this, 1);
1402}
1403
1404template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1405_Rp
1406__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
1407{
1408    typedef __invoke_void_return_wrapper<_Rp> _Invoker;
1409    return _Invoker::__call(__f_.first(), _VSTD::forward<_ArgTypes>(__arg)...);
1410}
1411
1412#ifndef _LIBCPP_NO_RTTI
1413
1414template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1415const void*
1416__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target(const type_info& __ti) const _NOEXCEPT
1417{
1418    if (__ti == typeid(_Fp))
1419        return &__f_.first();
1420    return (const void*)0;
1421}
1422
1423template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1424const std::type_info&
1425__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
1426{
1427    return typeid(_Fp);
1428}
1429
1430#endif  // _LIBCPP_NO_RTTI
1431
1432}  // __function
1433
1434template<class _Rp, class ..._ArgTypes>
1435class _LIBCPP_TYPE_VIS_ONLY function<_Rp(_ArgTypes...)>
1436    : public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
1437      public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
1438{
1439    typedef __function::__base<_Rp(_ArgTypes...)> __base;
1440    typename aligned_storage<3*sizeof(void*)>::type __buf_;
1441    __base* __f_;
1442
1443    template <class _Fp>
1444        _LIBCPP_INLINE_VISIBILITY
1445        static bool __not_null(const _Fp&) {return true;}
1446    template <class _R2, class ..._Ap>
1447        _LIBCPP_INLINE_VISIBILITY
1448        static bool __not_null(_R2 (*__p)(_Ap...)) {return __p;}
1449    template <class _R2, class _Cp, class ..._Ap>
1450        _LIBCPP_INLINE_VISIBILITY
1451        static bool __not_null(_R2 (_Cp::*__p)(_Ap...)) {return __p;}
1452    template <class _R2, class _Cp, class ..._Ap>
1453        _LIBCPP_INLINE_VISIBILITY
1454        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) const) {return __p;}
1455    template <class _R2, class _Cp, class ..._Ap>
1456        _LIBCPP_INLINE_VISIBILITY
1457        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) volatile) {return __p;}
1458    template <class _R2, class _Cp, class ..._Ap>
1459        _LIBCPP_INLINE_VISIBILITY
1460        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) const volatile) {return __p;}
1461    template <class _R2, class ..._Ap>
1462        _LIBCPP_INLINE_VISIBILITY
1463        static bool __not_null(const function<_R2(_Ap...)>& __p) {return !!__p;}
1464
1465    template <class _Fp, bool = !is_same<_Fp, function>::value &&
1466                                __invokable<_Fp&, _ArgTypes...>::value>
1467        struct __callable;
1468    template <class _Fp>
1469        struct __callable<_Fp, true>
1470        {
1471            static const bool value = is_same<void, _Rp>::value ||
1472                is_convertible<typename __invoke_of<_Fp&, _ArgTypes...>::type,
1473                               _Rp>::value;
1474        };
1475    template <class _Fp>
1476        struct __callable<_Fp, false>
1477        {
1478            static const bool value = false;
1479        };
1480public:
1481    typedef _Rp result_type;
1482
1483    // construct/copy/destroy:
1484    _LIBCPP_INLINE_VISIBILITY
1485    function() _NOEXCEPT : __f_(0) {}
1486    _LIBCPP_INLINE_VISIBILITY
1487    function(nullptr_t) _NOEXCEPT : __f_(0) {}
1488    function(const function&);
1489    function(function&&) _NOEXCEPT;
1490    template<class _Fp>
1491      function(_Fp, typename enable_if
1492                                     <
1493                                        __callable<_Fp>::value &&
1494                                        !is_same<_Fp, function>::value
1495                                      >::type* = 0);
1496
1497    template<class _Alloc>
1498      _LIBCPP_INLINE_VISIBILITY
1499      function(allocator_arg_t, const _Alloc&) _NOEXCEPT : __f_(0) {}
1500    template<class _Alloc>
1501      _LIBCPP_INLINE_VISIBILITY
1502      function(allocator_arg_t, const _Alloc&, nullptr_t) _NOEXCEPT : __f_(0) {}
1503    template<class _Alloc>
1504      function(allocator_arg_t, const _Alloc&, const function&);
1505    template<class _Alloc>
1506      function(allocator_arg_t, const _Alloc&, function&&);
1507    template<class _Fp, class _Alloc>
1508      function(allocator_arg_t, const _Alloc& __a, _Fp __f,
1509               typename enable_if<__callable<_Fp>::value>::type* = 0);
1510
1511    function& operator=(const function&);
1512    function& operator=(function&&) _NOEXCEPT;
1513    function& operator=(nullptr_t) _NOEXCEPT;
1514    template<class _Fp>
1515      typename enable_if
1516      <
1517        __callable<typename decay<_Fp>::type>::value &&
1518        !is_same<typename remove_reference<_Fp>::type, function>::value,
1519        function&
1520      >::type
1521      operator=(_Fp&&);
1522
1523    ~function();
1524
1525    // function modifiers:
1526    void swap(function&) _NOEXCEPT;
1527    template<class _Fp, class _Alloc>
1528      _LIBCPP_INLINE_VISIBILITY
1529      void assign(_Fp&& __f, const _Alloc& __a)
1530        {function(allocator_arg, __a, _VSTD::forward<_Fp>(__f)).swap(*this);}
1531
1532    // function capacity:
1533    _LIBCPP_INLINE_VISIBILITY
1534        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return __f_;}
1535
1536    // deleted overloads close possible hole in the type system
1537    template<class _R2, class... _ArgTypes2>
1538      bool operator==(const function<_R2(_ArgTypes2...)>&) const = delete;
1539    template<class _R2, class... _ArgTypes2>
1540      bool operator!=(const function<_R2(_ArgTypes2...)>&) const = delete;
1541public:
1542    // function invocation:
1543    _Rp operator()(_ArgTypes...) const;
1544
1545#ifndef _LIBCPP_NO_RTTI
1546    // function target access:
1547    const std::type_info& target_type() const _NOEXCEPT;
1548    template <typename _Tp> _Tp* target() _NOEXCEPT;
1549    template <typename _Tp> const _Tp* target() const _NOEXCEPT;
1550#endif  // _LIBCPP_NO_RTTI
1551};
1552
1553template<class _Rp, class ..._ArgTypes>
1554function<_Rp(_ArgTypes...)>::function(const function& __f)
1555{
1556    if (__f.__f_ == 0)
1557        __f_ = 0;
1558    else if (__f.__f_ == (const __base*)&__f.__buf_)
1559    {
1560        __f_ = (__base*)&__buf_;
1561        __f.__f_->__clone(__f_);
1562    }
1563    else
1564        __f_ = __f.__f_->__clone();
1565}
1566
1567template<class _Rp, class ..._ArgTypes>
1568template <class _Alloc>
1569function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
1570                                     const function& __f)
1571{
1572    if (__f.__f_ == 0)
1573        __f_ = 0;
1574    else if (__f.__f_ == (const __base*)&__f.__buf_)
1575    {
1576        __f_ = (__base*)&__buf_;
1577        __f.__f_->__clone(__f_);
1578    }
1579    else
1580        __f_ = __f.__f_->__clone();
1581}
1582
1583template<class _Rp, class ..._ArgTypes>
1584function<_Rp(_ArgTypes...)>::function(function&& __f) _NOEXCEPT
1585{
1586    if (__f.__f_ == 0)
1587        __f_ = 0;
1588    else if (__f.__f_ == (__base*)&__f.__buf_)
1589    {
1590        __f_ = (__base*)&__buf_;
1591        __f.__f_->__clone(__f_);
1592    }
1593    else
1594    {
1595        __f_ = __f.__f_;
1596        __f.__f_ = 0;
1597    }
1598}
1599
1600template<class _Rp, class ..._ArgTypes>
1601template <class _Alloc>
1602function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
1603                                     function&& __f)
1604{
1605    if (__f.__f_ == 0)
1606        __f_ = 0;
1607    else if (__f.__f_ == (__base*)&__f.__buf_)
1608    {
1609        __f_ = (__base*)&__buf_;
1610        __f.__f_->__clone(__f_);
1611    }
1612    else
1613    {
1614        __f_ = __f.__f_;
1615        __f.__f_ = 0;
1616    }
1617}
1618
1619template<class _Rp, class ..._ArgTypes>
1620template <class _Fp>
1621function<_Rp(_ArgTypes...)>::function(_Fp __f,
1622                                     typename enable_if
1623                                     <
1624                                        __callable<_Fp>::value &&
1625                                        !is_same<_Fp, function>::value
1626                                     >::type*)
1627    : __f_(0)
1628{
1629    if (__not_null(__f))
1630    {
1631        typedef __function::__func<_Fp, allocator<_Fp>, _Rp(_ArgTypes...)> _FF;
1632        if (sizeof(_FF) <= sizeof(__buf_) && is_nothrow_copy_constructible<_Fp>::value)
1633        {
1634            __f_ = (__base*)&__buf_;
1635            ::new (__f_) _FF(_VSTD::move(__f));
1636        }
1637        else
1638        {
1639            typedef allocator<_FF> _Ap;
1640            _Ap __a;
1641            typedef __allocator_destructor<_Ap> _Dp;
1642            unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1643            ::new (__hold.get()) _FF(_VSTD::move(__f), allocator<_Fp>(__a));
1644            __f_ = __hold.release();
1645        }
1646    }
1647}
1648
1649template<class _Rp, class ..._ArgTypes>
1650template <class _Fp, class _Alloc>
1651function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc& __a0, _Fp __f,
1652                                     typename enable_if<__callable<_Fp>::value>::type*)
1653    : __f_(0)
1654{
1655    typedef allocator_traits<_Alloc> __alloc_traits;
1656    if (__not_null(__f))
1657    {
1658        typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _FF;
1659        typedef typename __rebind_alloc_helper<__alloc_traits, _FF>::type _Ap;
1660        _Ap __a(__a0);
1661        if (sizeof(_FF) <= sizeof(__buf_) && 
1662            is_nothrow_copy_constructible<_Fp>::value && is_nothrow_copy_constructible<_Ap>::value)
1663        {
1664            __f_ = (__base*)&__buf_;
1665            ::new (__f_) _FF(_VSTD::move(__f), _Alloc(__a));
1666        }
1667        else
1668        {
1669            typedef __allocator_destructor<_Ap> _Dp;
1670            unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1671            ::new (__hold.get()) _FF(_VSTD::move(__f), _Alloc(__a));
1672            __f_ = __hold.release();
1673        }
1674    }
1675}
1676
1677template<class _Rp, class ..._ArgTypes>
1678function<_Rp(_ArgTypes...)>&
1679function<_Rp(_ArgTypes...)>::operator=(const function& __f)
1680{
1681    function(__f).swap(*this);
1682    return *this;
1683}
1684
1685template<class _Rp, class ..._ArgTypes>
1686function<_Rp(_ArgTypes...)>&
1687function<_Rp(_ArgTypes...)>::operator=(function&& __f) _NOEXCEPT
1688{
1689    if (__f_ == (__base*)&__buf_)
1690        __f_->destroy();
1691    else if (__f_)
1692        __f_->destroy_deallocate();
1693    __f_ = 0;
1694    if (__f.__f_ == 0)
1695        __f_ = 0;
1696    else if (__f.__f_ == (__base*)&__f.__buf_)
1697    {
1698        __f_ = (__base*)&__buf_;
1699        __f.__f_->__clone(__f_);
1700    }
1701    else
1702    {
1703        __f_ = __f.__f_;
1704        __f.__f_ = 0;
1705    }
1706    return *this;
1707}
1708
1709template<class _Rp, class ..._ArgTypes>
1710function<_Rp(_ArgTypes...)>&
1711function<_Rp(_ArgTypes...)>::operator=(nullptr_t) _NOEXCEPT
1712{
1713    if (__f_ == (__base*)&__buf_)
1714        __f_->destroy();
1715    else if (__f_)
1716        __f_->destroy_deallocate();
1717    __f_ = 0;
1718    return *this;
1719}
1720
1721template<class _Rp, class ..._ArgTypes>
1722template <class _Fp>
1723typename enable_if
1724<
1725    function<_Rp(_ArgTypes...)>::template __callable<typename decay<_Fp>::type>::value &&
1726    !is_same<typename remove_reference<_Fp>::type, function<_Rp(_ArgTypes...)>>::value,
1727    function<_Rp(_ArgTypes...)>&
1728>::type
1729function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f)
1730{
1731    function(_VSTD::forward<_Fp>(__f)).swap(*this);
1732    return *this;
1733}
1734
1735template<class _Rp, class ..._ArgTypes>
1736function<_Rp(_ArgTypes...)>::~function()
1737{
1738    if (__f_ == (__base*)&__buf_)
1739        __f_->destroy();
1740    else if (__f_)
1741        __f_->destroy_deallocate();
1742}
1743
1744template<class _Rp, class ..._ArgTypes>
1745void
1746function<_Rp(_ArgTypes...)>::swap(function& __f) _NOEXCEPT
1747{
1748    if (__f_ == (__base*)&__buf_ && __f.__f_ == (__base*)&__f.__buf_)
1749    {
1750        typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
1751        __base* __t = (__base*)&__tempbuf;
1752        __f_->__clone(__t);
1753        __f_->destroy();
1754        __f_ = 0;
1755        __f.__f_->__clone((__base*)&__buf_);
1756        __f.__f_->destroy();
1757        __f.__f_ = 0;
1758        __f_ = (__base*)&__buf_;
1759        __t->__clone((__base*)&__f.__buf_);
1760        __t->destroy();
1761        __f.__f_ = (__base*)&__f.__buf_;
1762    }
1763    else if (__f_ == (__base*)&__buf_)
1764    {
1765        __f_->__clone((__base*)&__f.__buf_);
1766        __f_->destroy();
1767        __f_ = __f.__f_;
1768        __f.__f_ = (__base*)&__f.__buf_;
1769    }
1770    else if (__f.__f_ == (__base*)&__f.__buf_)
1771    {
1772        __f.__f_->__clone((__base*)&__buf_);
1773        __f.__f_->destroy();
1774        __f.__f_ = __f_;
1775        __f_ = (__base*)&__buf_;
1776    }
1777    else
1778        _VSTD::swap(__f_, __f.__f_);
1779}
1780
1781template<class _Rp, class ..._ArgTypes>
1782_Rp
1783function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
1784{
1785#ifndef _LIBCPP_NO_EXCEPTIONS
1786    if (__f_ == 0)
1787        throw bad_function_call();
1788#endif  // _LIBCPP_NO_EXCEPTIONS
1789    return (*__f_)(_VSTD::forward<_ArgTypes>(__arg)...);
1790}
1791
1792#ifndef _LIBCPP_NO_RTTI
1793
1794template<class _Rp, class ..._ArgTypes>
1795const std::type_info&
1796function<_Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
1797{
1798    if (__f_ == 0)
1799        return typeid(void);
1800    return __f_->target_type();
1801}
1802
1803template<class _Rp, class ..._ArgTypes>
1804template <typename _Tp>
1805_Tp*
1806function<_Rp(_ArgTypes...)>::target() _NOEXCEPT
1807{
1808    if (__f_ == 0)
1809        return (_Tp*)0;
1810    return (_Tp*)__f_->target(typeid(_Tp));
1811}
1812
1813template<class _Rp, class ..._ArgTypes>
1814template <typename _Tp>
1815const _Tp*
1816function<_Rp(_ArgTypes...)>::target() const _NOEXCEPT
1817{
1818    if (__f_ == 0)
1819        return (const _Tp*)0;
1820    return (const _Tp*)__f_->target(typeid(_Tp));
1821}
1822
1823#endif  // _LIBCPP_NO_RTTI
1824
1825template <class _Rp, class... _ArgTypes>
1826inline _LIBCPP_INLINE_VISIBILITY
1827bool
1828operator==(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return !__f;}
1829
1830template <class _Rp, class... _ArgTypes>
1831inline _LIBCPP_INLINE_VISIBILITY
1832bool
1833operator==(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return !__f;}
1834
1835template <class _Rp, class... _ArgTypes>
1836inline _LIBCPP_INLINE_VISIBILITY
1837bool
1838operator!=(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return (bool)__f;}
1839
1840template <class _Rp, class... _ArgTypes>
1841inline _LIBCPP_INLINE_VISIBILITY
1842bool
1843operator!=(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return (bool)__f;}
1844
1845template <class _Rp, class... _ArgTypes>
1846inline _LIBCPP_INLINE_VISIBILITY
1847void
1848swap(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y) _NOEXCEPT
1849{return __x.swap(__y);}
1850
1851template<class _Tp> struct __is_bind_expression : public false_type {};
1852template<class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_bind_expression
1853    : public __is_bind_expression<typename remove_cv<_Tp>::type> {};
1854
1855template<class _Tp> struct __is_placeholder : public integral_constant<int, 0> {};
1856template<class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_placeholder
1857    : public __is_placeholder<typename remove_cv<_Tp>::type> {};
1858
1859namespace placeholders
1860{
1861
1862template <int _Np> struct __ph {};
1863
1864_LIBCPP_FUNC_VIS extern __ph<1>   _1;
1865_LIBCPP_FUNC_VIS extern __ph<2>   _2;
1866_LIBCPP_FUNC_VIS extern __ph<3>   _3;
1867_LIBCPP_FUNC_VIS extern __ph<4>   _4;
1868_LIBCPP_FUNC_VIS extern __ph<5>   _5;
1869_LIBCPP_FUNC_VIS extern __ph<6>   _6;
1870_LIBCPP_FUNC_VIS extern __ph<7>   _7;
1871_LIBCPP_FUNC_VIS extern __ph<8>   _8;
1872_LIBCPP_FUNC_VIS extern __ph<9>   _9;
1873_LIBCPP_FUNC_VIS extern __ph<10> _10;
1874
1875}  // placeholders
1876
1877template<int _Np>
1878struct __is_placeholder<placeholders::__ph<_Np> >
1879    : public integral_constant<int, _Np> {};
1880
1881template <class _Tp, class _Uj>
1882inline _LIBCPP_INLINE_VISIBILITY
1883_Tp&
1884__mu(reference_wrapper<_Tp> __t, _Uj&)
1885{
1886    return __t.get();
1887}
1888
1889template <class _Ti, class ..._Uj, size_t ..._Indx>
1890inline _LIBCPP_INLINE_VISIBILITY
1891typename __invoke_of<_Ti&, _Uj...>::type
1892__mu_expand(_Ti& __ti, tuple<_Uj...>& __uj, __tuple_indices<_Indx...>)
1893{
1894    return __ti(_VSTD::forward<_Uj>(_VSTD::get<_Indx>(__uj))...);
1895}
1896
1897template <class _Ti, class ..._Uj>
1898inline _LIBCPP_INLINE_VISIBILITY
1899typename __lazy_enable_if
1900<
1901    is_bind_expression<_Ti>::value,
1902    __invoke_of<_Ti&, _Uj...>
1903>::type
1904__mu(_Ti& __ti, tuple<_Uj...>& __uj)
1905{
1906    typedef typename __make_tuple_indices<sizeof...(_Uj)>::type __indices;
1907    return  __mu_expand(__ti, __uj, __indices());
1908}
1909
1910template <bool IsPh, class _Ti, class _Uj>
1911struct __mu_return2 {};
1912
1913template <class _Ti, class _Uj>
1914struct __mu_return2<true, _Ti, _Uj>
1915{
1916    typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _Uj>::type type;
1917};
1918
1919template <class _Ti, class _Uj>
1920inline _LIBCPP_INLINE_VISIBILITY
1921typename enable_if
1922<
1923    0 < is_placeholder<_Ti>::value,
1924    typename __mu_return2<0 < is_placeholder<_Ti>::value, _Ti, _Uj>::type
1925>::type
1926__mu(_Ti&, _Uj& __uj)
1927{
1928    const size_t _Indx = is_placeholder<_Ti>::value - 1;
1929    return _VSTD::forward<typename tuple_element<_Indx, _Uj>::type>(_VSTD::get<_Indx>(__uj));
1930}
1931
1932template <class _Ti, class _Uj>
1933inline _LIBCPP_INLINE_VISIBILITY
1934typename enable_if
1935<
1936    !is_bind_expression<_Ti>::value &&
1937    is_placeholder<_Ti>::value == 0 &&
1938    !__is_reference_wrapper<_Ti>::value,
1939    _Ti&
1940>::type
1941__mu(_Ti& __ti, _Uj&)
1942{
1943    return __ti;
1944}
1945
1946template <class _Ti, bool IsReferenceWrapper, bool IsBindEx, bool IsPh,
1947          class _TupleUj>
1948struct ____mu_return;
1949
1950template <bool _Invokable, class _Ti, class ..._Uj>
1951struct ____mu_return_invokable  // false
1952{
1953    typedef __nat type;
1954};
1955
1956template <class _Ti, class ..._Uj>
1957struct ____mu_return_invokable<true, _Ti, _Uj...>
1958{
1959    typedef typename __invoke_of<_Ti&, _Uj...>::type type;
1960};
1961
1962template <class _Ti, class ..._Uj>
1963struct ____mu_return<_Ti, false, true, false, tuple<_Uj...> >
1964    : public ____mu_return_invokable<__invokable<_Ti&, _Uj...>::value, _Ti, _Uj...>
1965{
1966};
1967
1968template <class _Ti, class _TupleUj>
1969struct ____mu_return<_Ti, false, false, true, _TupleUj>
1970{
1971    typedef typename tuple_element<is_placeholder<_Ti>::value - 1,
1972                                   _TupleUj>::type&& type;
1973};
1974
1975template <class _Ti, class _TupleUj>
1976struct ____mu_return<_Ti, true, false, false, _TupleUj>
1977{
1978    typedef typename _Ti::type& type;
1979};
1980
1981template <class _Ti, class _TupleUj>
1982struct ____mu_return<_Ti, false, false, false, _TupleUj>
1983{
1984    typedef _Ti& type;
1985};
1986
1987template <class _Ti, class _TupleUj>
1988struct __mu_return
1989    : public ____mu_return<_Ti,
1990                           __is_reference_wrapper<_Ti>::value,
1991                           is_bind_expression<_Ti>::value,
1992                           0 < is_placeholder<_Ti>::value &&
1993                           is_placeholder<_Ti>::value <= tuple_size<_TupleUj>::value,
1994                           _TupleUj>
1995{
1996};
1997
1998template <class _Fp, class _BoundArgs, class _TupleUj>
1999struct __is_valid_bind_return
2000{
2001    static const bool value = false;
2002};
2003
2004template <class _Fp, class ..._BoundArgs, class _TupleUj>
2005struct __is_valid_bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj>
2006{
2007    static const bool value = __invokable<_Fp,
2008                    typename __mu_return<_BoundArgs, _TupleUj>::type...>::value;
2009};
2010
2011template <class _Fp, class ..._BoundArgs, class _TupleUj>
2012struct __is_valid_bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj>
2013{
2014    static const bool value = __invokable<_Fp,
2015                    typename __mu_return<const _BoundArgs, _TupleUj>::type...>::value;
2016};
2017
2018template <class _Fp, class _BoundArgs, class _TupleUj,
2019          bool = __is_valid_bind_return<_Fp, _BoundArgs, _TupleUj>::value>
2020struct __bind_return;
2021
2022template <class _Fp, class ..._BoundArgs, class _TupleUj>
2023struct __bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj, true>
2024{
2025    typedef typename __invoke_of
2026    <
2027        _Fp&,
2028        typename __mu_return
2029        <
2030            _BoundArgs,
2031            _TupleUj
2032        >::type...
2033    >::type type;
2034};
2035
2036template <class _Fp, class ..._BoundArgs, class _TupleUj>
2037struct __bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj, true>
2038{
2039    typedef typename __invoke_of
2040    <
2041        _Fp&,
2042        typename __mu_return
2043        <
2044            const _BoundArgs,
2045            _TupleUj
2046        >::type...
2047    >::type type;
2048};
2049
2050template <class _Fp, class _BoundArgs, size_t ..._Indx, class _Args>
2051inline _LIBCPP_INLINE_VISIBILITY
2052typename __bind_return<_Fp, _BoundArgs, _Args>::type
2053__apply_functor(_Fp& __f, _BoundArgs& __bound_args, __tuple_indices<_Indx...>,
2054                _Args&& __args)
2055{
2056    return __invoke(__f, __mu(_VSTD::get<_Indx>(__bound_args), __args)...);
2057}
2058
2059template<class _Fp, class ..._BoundArgs>
2060class __bind
2061    : public __weak_result_type<typename decay<_Fp>::type>
2062{
2063protected:
2064    typedef typename decay<_Fp>::type _Fd;
2065    typedef tuple<typename decay<_BoundArgs>::type...> _Td;
2066private:
2067    _Fd __f_;
2068    _Td __bound_args_;
2069
2070    typedef typename __make_tuple_indices<sizeof...(_BoundArgs)>::type __indices;
2071public:
2072#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2073
2074    _LIBCPP_INLINE_VISIBILITY
2075    __bind(const __bind& __b)
2076        : __f_(__b.__f_),
2077          __bound_args_(__b.__bound_args_) {}
2078
2079    _LIBCPP_INLINE_VISIBILITY
2080    __bind& operator=(const __bind& __b)
2081    {
2082        __f_ = __b.__f_;
2083        __bound_args_ = __b.__bound_args_;
2084        return *this;
2085    }
2086
2087    _LIBCPP_INLINE_VISIBILITY
2088    __bind(__bind&& __b)
2089        : __f_(_VSTD::move(__b.__f_)),
2090          __bound_args_(_VSTD::move(__b.__bound_args_)) {}
2091
2092    _LIBCPP_INLINE_VISIBILITY
2093    __bind& operator=(__bind&& __b)
2094    {
2095        __f_ = _VSTD::move(__b.__f_);
2096        __bound_args_ = _VSTD::move(__b.__bound_args_);
2097        return *this;
2098    }
2099
2100#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2101
2102    template <class _Gp, class ..._BA,
2103              class = typename enable_if
2104                               <
2105                                  is_constructible<_Fd, _Gp>::value &&
2106                                  !is_same<typename remove_reference<_Gp>::type,
2107                                           __bind>::value
2108                               >::type>
2109      _LIBCPP_INLINE_VISIBILITY
2110      explicit __bind(_Gp&& __f, _BA&& ...__bound_args)
2111        : __f_(_VSTD::forward<_Gp>(__f)),
2112          __bound_args_(_VSTD::forward<_BA>(__bound_args)...) {}
2113
2114    template <class ..._Args>
2115        _LIBCPP_INLINE_VISIBILITY
2116        typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
2117        operator()(_Args&& ...__args)
2118        {
2119            return __apply_functor(__f_, __bound_args_, __indices(),
2120                                  tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
2121        }
2122
2123    template <class ..._Args>
2124        _LIBCPP_INLINE_VISIBILITY
2125        typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type
2126        operator()(_Args&& ...__args) const
2127        {
2128            return __apply_functor(__f_, __bound_args_, __indices(),
2129                                   tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
2130        }
2131};
2132
2133template<class _Fp, class ..._BoundArgs>
2134struct __is_bind_expression<__bind<_Fp, _BoundArgs...> > : public true_type {};
2135
2136template<class _Rp, class _Fp, class ..._BoundArgs>
2137class __bind_r
2138    : public __bind<_Fp, _BoundArgs...>
2139{
2140    typedef __bind<_Fp, _BoundArgs...> base;
2141    typedef typename base::_Fd _Fd;
2142    typedef typename base::_Td _Td;
2143public:
2144    typedef _Rp result_type;
2145
2146#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2147
2148    _LIBCPP_INLINE_VISIBILITY
2149    __bind_r(const __bind_r& __b)
2150        : base(_VSTD::forward<const base&>(__b)) {}
2151
2152    _LIBCPP_INLINE_VISIBILITY
2153    __bind_r& operator=(const __bind_r& __b)
2154    {
2155        base::operator=(_VSTD::forward<const base&>(__b));
2156        return *this;
2157    }
2158
2159    _LIBCPP_INLINE_VISIBILITY
2160    __bind_r(__bind_r&& __b)
2161        : base(_VSTD::forward<base>(__b)) {}
2162
2163    _LIBCPP_INLINE_VISIBILITY
2164    __bind_r& operator=(__bind_r&& __b)
2165    {
2166        base::operator=(_VSTD::forward<base>(__b));
2167        return *this;
2168    }
2169
2170#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2171
2172    template <class _Gp, class ..._BA,
2173              class = typename enable_if
2174                               <
2175                                  is_constructible<_Fd, _Gp>::value &&
2176                                  !is_same<typename remove_reference<_Gp>::type,
2177                                           __bind_r>::value
2178                               >::type>
2179      _LIBCPP_INLINE_VISIBILITY
2180      explicit __bind_r(_Gp&& __f, _BA&& ...__bound_args)
2181        : base(_VSTD::forward<_Gp>(__f),
2182               _VSTD::forward<_BA>(__bound_args)...) {}
2183
2184    template <class ..._Args>
2185        _LIBCPP_INLINE_VISIBILITY
2186        typename enable_if
2187        <
2188            is_convertible<typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type,
2189                           result_type>::value || is_void<_Rp>::value,
2190            result_type
2191        >::type
2192        operator()(_Args&& ...__args)
2193        {
2194            typedef __invoke_void_return_wrapper<_Rp> _Invoker;
2195            return _Invoker::__call(static_cast<base&>(*this), _VSTD::forward<_Args>(__args)...);
2196        }
2197
2198    template <class ..._Args>
2199        _LIBCPP_INLINE_VISIBILITY
2200        typename enable_if
2201        <
2202            is_convertible<typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type,
2203                           result_type>::value || is_void<_Rp>::value,
2204            result_type
2205        >::type
2206        operator()(_Args&& ...__args) const
2207        {
2208            typedef __invoke_void_return_wrapper<_Rp> _Invoker;
2209            return _Invoker::__call(static_cast<base const&>(*this), _VSTD::forward<_Args>(__args)...);
2210        }
2211};
2212
2213template<class _Rp, class _Fp, class ..._BoundArgs>
2214struct __is_bind_expression<__bind_r<_Rp, _Fp, _BoundArgs...> > : public true_type {};
2215
2216template<class _Fp, class ..._BoundArgs>
2217inline _LIBCPP_INLINE_VISIBILITY
2218__bind<_Fp, _BoundArgs...>
2219bind(_Fp&& __f, _BoundArgs&&... __bound_args)
2220{
2221    typedef __bind<_Fp, _BoundArgs...> type;
2222    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
2223}
2224
2225template<class _Rp, class _Fp, class ..._BoundArgs>
2226inline _LIBCPP_INLINE_VISIBILITY
2227__bind_r<_Rp, _Fp, _BoundArgs...>
2228bind(_Fp&& __f, _BoundArgs&&... __bound_args)
2229{
2230    typedef __bind_r<_Rp, _Fp, _BoundArgs...> type;
2231    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
2232}
2233
2234#endif  // _LIBCPP_HAS_NO_VARIADICS
2235
2236template <>
2237struct _LIBCPP_TYPE_VIS_ONLY hash<bool>
2238    : public unary_function<bool, size_t>
2239{
2240    _LIBCPP_INLINE_VISIBILITY
2241    size_t operator()(bool __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2242};
2243
2244template <>
2245struct _LIBCPP_TYPE_VIS_ONLY hash<char>
2246    : public unary_function<char, size_t>
2247{
2248    _LIBCPP_INLINE_VISIBILITY
2249    size_t operator()(char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2250};
2251
2252template <>
2253struct _LIBCPP_TYPE_VIS_ONLY hash<signed char>
2254    : public unary_function<signed char, size_t>
2255{
2256    _LIBCPP_INLINE_VISIBILITY
2257    size_t operator()(signed char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2258};
2259
2260template <>
2261struct _LIBCPP_TYPE_VIS_ONLY hash<unsigned char>
2262    : public unary_function<unsigned char, size_t>
2263{
2264    _LIBCPP_INLINE_VISIBILITY
2265    size_t operator()(unsigned char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2266};
2267
2268#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
2269
2270template <>
2271struct _LIBCPP_TYPE_VIS_ONLY hash<char16_t>
2272    : public unary_function<char16_t, size_t>
2273{
2274    _LIBCPP_INLINE_VISIBILITY
2275    size_t operator()(char16_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2276};
2277
2278template <>
2279struct _LIBCPP_TYPE_VIS_ONLY hash<char32_t>
2280    : public unary_function<char32_t, size_t>
2281{
2282    _LIBCPP_INLINE_VISIBILITY
2283    size_t operator()(char32_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2284};
2285
2286#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
2287
2288template <>
2289struct _LIBCPP_TYPE_VIS_ONLY hash<wchar_t>
2290    : public unary_function<wchar_t, size_t>
2291{
2292    _LIBCPP_INLINE_VISIBILITY
2293    size_t operator()(wchar_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2294};
2295
2296template <>
2297struct _LIBCPP_TYPE_VIS_ONLY hash<short>
2298    : public unary_function<short, size_t>
2299{
2300    _LIBCPP_INLINE_VISIBILITY
2301    size_t operator()(short __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2302};
2303
2304template <>
2305struct _LIBCPP_TYPE_VIS_ONLY hash<unsigned short>
2306    : public unary_function<unsigned short, size_t>
2307{
2308    _LIBCPP_INLINE_VISIBILITY
2309    size_t operator()(unsigned short __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2310};
2311
2312template <>
2313struct _LIBCPP_TYPE_VIS_ONLY hash<int>
2314    : public unary_function<int, size_t>
2315{
2316    _LIBCPP_INLINE_VISIBILITY
2317    size_t operator()(int __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2318};
2319
2320template <>
2321struct _LIBCPP_TYPE_VIS_ONLY hash<unsigned int>
2322    : public unary_function<unsigned int, size_t>
2323{
2324    _LIBCPP_INLINE_VISIBILITY
2325    size_t operator()(unsigned int __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2326};
2327
2328template <>
2329struct _LIBCPP_TYPE_VIS_ONLY hash<long>
2330    : public unary_function<long, size_t>
2331{
2332    _LIBCPP_INLINE_VISIBILITY
2333    size_t operator()(long __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2334};
2335
2336template <>
2337struct _LIBCPP_TYPE_VIS_ONLY hash<unsigned long>
2338    : public unary_function<unsigned long, size_t>
2339{
2340    _LIBCPP_INLINE_VISIBILITY
2341    size_t operator()(unsigned long __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
2342};
2343
2344template <>
2345struct _LIBCPP_TYPE_VIS_ONLY hash<long long>
2346    : public __scalar_hash<long long>
2347{
2348};
2349
2350template <>
2351struct _LIBCPP_TYPE_VIS_ONLY hash<unsigned long long>
2352    : public __scalar_hash<unsigned long long>
2353{
2354};
2355
2356template <>
2357struct _LIBCPP_TYPE_VIS_ONLY hash<float>
2358    : public __scalar_hash<float>
2359{
2360    _LIBCPP_INLINE_VISIBILITY
2361    size_t operator()(float __v) const _NOEXCEPT
2362    {
2363        // -0.0 and 0.0 should return same hash
2364       if (__v == 0)
2365           return 0;
2366        return __scalar_hash<float>::operator()(__v);
2367    }
2368};
2369
2370template <>
2371struct _LIBCPP_TYPE_VIS_ONLY hash<double>
2372    : public __scalar_hash<double>
2373{
2374    _LIBCPP_INLINE_VISIBILITY
2375    size_t operator()(double __v) const _NOEXCEPT
2376    {
2377        // -0.0 and 0.0 should return same hash
2378       if (__v == 0)
2379           return 0;
2380        return __scalar_hash<double>::operator()(__v);
2381    }
2382};
2383
2384template <>
2385struct _LIBCPP_TYPE_VIS_ONLY hash<long double>
2386    : public __scalar_hash<long double>
2387{
2388    _LIBCPP_INLINE_VISIBILITY
2389    size_t operator()(long double __v) const _NOEXCEPT
2390    {
2391        // -0.0 and 0.0 should return same hash
2392        if (__v == 0)
2393            return 0;
2394#if defined(__i386__)
2395        // Zero out padding bits
2396        union
2397        {
2398            long double __t;
2399            struct
2400            {
2401                size_t __a;
2402                size_t __b;
2403                size_t __c;
2404                size_t __d;
2405            };
2406        } __u;
2407        __u.__a = 0;
2408        __u.__b = 0;
2409        __u.__c = 0;
2410        __u.__d = 0;
2411        __u.__t = __v;
2412        return __u.__a ^ __u.__b ^ __u.__c ^ __u.__d;
2413#elif defined(__x86_64__)
2414        // Zero out padding bits
2415        union
2416        {
2417            long double __t;
2418            struct
2419            {
2420                size_t __a;
2421                size_t __b;
2422            };
2423        } __u;
2424        __u.__a = 0;
2425        __u.__b = 0;
2426        __u.__t = __v;
2427        return __u.__a ^ __u.__b;
2428#else
2429        return __scalar_hash<long double>::operator()(__v);
2430#endif
2431    }
2432};
2433
2434#if _LIBCPP_STD_VER > 11
2435template <class _Tp>
2436struct _LIBCPP_TYPE_VIS_ONLY hash
2437    : public unary_function<_Tp, size_t>
2438{
2439    static_assert(is_enum<_Tp>::value, "This hash only works for enumeration types");
2440
2441    _LIBCPP_INLINE_VISIBILITY
2442    size_t operator()(_Tp __v) const _NOEXCEPT
2443    {
2444        typedef typename underlying_type<_Tp>::type type;
2445        return hash<type>{}(static_cast<type>(__v));
2446    }
2447};
2448#endif
2449
2450
2451#if _LIBCPP_STD_VER > 14
2452template <class _Fn, class ..._Args>
2453result_of_t<_Fn&&(_Args&&...)>
2454invoke(_Fn&& __f, _Args&&... __args) {
2455    return __invoke(_VSTD::forward<_Fn>(__f), _VSTD::forward<_Args>(__args)...);
2456}
2457#endif
2458
2459// struct hash<T*> in <memory>
2460
2461_LIBCPP_END_NAMESPACE_STD
2462
2463#endif  // _LIBCPP_FUNCTIONAL
2464