xref: /netbsd-src/external/apache2/llvm/dist/libcxx/include/functional (revision 4d6fc14bc9b0c5bf3e30be318c143ee82cadd108)
1// -*- C++ -*-
2//===------------------------ functional ----------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_FUNCTIONAL
11#define _LIBCPP_FUNCTIONAL
12
13/*
14    functional synopsis
15
16namespace std
17{
18
19template <class Arg, class Result>
20struct unary_function
21{
22    typedef Arg    argument_type;
23    typedef Result result_type;
24};
25
26template <class Arg1, class Arg2, class Result>
27struct binary_function
28{
29    typedef Arg1   first_argument_type;
30    typedef Arg2   second_argument_type;
31    typedef Result result_type;
32};
33
34template <class T>
35class reference_wrapper
36    : public unary_function<T1, R> // if wrapping a unary functor
37    : public binary_function<T1, T2, R> // if wraping a binary functor
38{
39public:
40    // types
41    typedef T type;
42    typedef see below result_type; // Not always defined
43
44    // construct/copy/destroy
45    template<class U>
46      reference_wrapper(U&&);
47    reference_wrapper(const reference_wrapper<T>& x) noexcept;
48
49    // assignment
50    reference_wrapper& operator=(const reference_wrapper<T>& x) noexcept;
51
52    // access
53    operator T& () const noexcept;
54    T& get() const noexcept;
55
56    // invoke
57    template <class... ArgTypes>
58      typename result_of<T&(ArgTypes&&...)>::type
59          operator() (ArgTypes&&...) const;
60};
61
62template <class T>
63  reference_wrapper(T&) -> reference_wrapper<T>;
64
65template <class T> reference_wrapper<T> ref(T& t) noexcept;
66template <class T> void ref(const T&& t) = delete;
67template <class T> reference_wrapper<T> ref(reference_wrapper<T>t) noexcept;
68
69template <class T> reference_wrapper<const T> cref(const T& t) noexcept;
70template <class T> void cref(const T&& t) = delete;
71template <class T> reference_wrapper<const T> cref(reference_wrapper<T> t) noexcept;
72
73template <class T> struct unwrap_reference;                                       // since C++20
74template <class T> struct unwrap_ref_decay : unwrap_reference<decay_t<T>> { };    // since C++20
75template <class T> using unwrap_reference_t = typename unwrap_reference<T>::type; // since C++20
76template <class T> using unwrap_ref_decay_t = typename unwrap_ref_decay<T>::type; // since C++20
77
78template <class T> // <class T=void> in C++14
79struct plus : binary_function<T, T, T>
80{
81    T operator()(const T& x, const T& y) const;
82};
83
84template <class T> // <class T=void> in C++14
85struct minus : binary_function<T, T, T>
86{
87    T operator()(const T& x, const T& y) const;
88};
89
90template <class T> // <class T=void> in C++14
91struct multiplies : binary_function<T, T, T>
92{
93    T operator()(const T& x, const T& y) const;
94};
95
96template <class T> // <class T=void> in C++14
97struct divides : binary_function<T, T, T>
98{
99    T operator()(const T& x, const T& y) const;
100};
101
102template <class T> // <class T=void> in C++14
103struct modulus : binary_function<T, T, T>
104{
105    T operator()(const T& x, const T& y) const;
106};
107
108template <class T> // <class T=void> in C++14
109struct negate : unary_function<T, T>
110{
111    T operator()(const T& x) const;
112};
113
114template <class T> // <class T=void> in C++14
115struct equal_to : binary_function<T, T, bool>
116{
117    bool operator()(const T& x, const T& y) const;
118};
119
120template <class T> // <class T=void> in C++14
121struct not_equal_to : binary_function<T, T, bool>
122{
123    bool operator()(const T& x, const T& y) const;
124};
125
126template <class T> // <class T=void> in C++14
127struct greater : binary_function<T, T, bool>
128{
129    bool operator()(const T& x, const T& y) const;
130};
131
132template <class T> // <class T=void> in C++14
133struct less : binary_function<T, T, bool>
134{
135    bool operator()(const T& x, const T& y) const;
136};
137
138template <class T> // <class T=void> in C++14
139struct greater_equal : binary_function<T, T, bool>
140{
141    bool operator()(const T& x, const T& y) const;
142};
143
144template <class T> // <class T=void> in C++14
145struct less_equal : binary_function<T, T, bool>
146{
147    bool operator()(const T& x, const T& y) const;
148};
149
150template <class T> // <class T=void> in C++14
151struct logical_and : binary_function<T, T, bool>
152{
153    bool operator()(const T& x, const T& y) const;
154};
155
156template <class T> // <class T=void> in C++14
157struct logical_or : binary_function<T, T, bool>
158{
159    bool operator()(const T& x, const T& y) const;
160};
161
162template <class T> // <class T=void> in C++14
163struct logical_not : unary_function<T, bool>
164{
165    bool operator()(const T& x) const;
166};
167
168template <class T> // <class T=void> in C++14
169struct bit_and : binary_function<T, T, T>
170{
171    T operator()(const T& x, const T& y) const;
172};
173
174template <class T> // <class T=void> in C++14
175struct bit_or : binary_function<T, T, T>
176{
177    T operator()(const T& x, const T& y) const;
178};
179
180template <class T> // <class T=void> in C++14
181struct bit_xor : binary_function<T, T, T>
182{
183    T operator()(const T& x, const T& y) const;
184};
185
186template <class T=void> // C++14
187struct bit_not : unary_function<T, T>
188{
189    T operator()(const T& x) const;
190};
191
192struct identity; // C++20
193
194template <class Predicate>
195class unary_negate // deprecated in C++17
196    : public unary_function<typename Predicate::argument_type, bool>
197{
198public:
199    explicit unary_negate(const Predicate& pred);
200    bool operator()(const typename Predicate::argument_type& x) const;
201};
202
203template <class Predicate> // deprecated in C++17
204unary_negate<Predicate> not1(const Predicate& pred);
205
206template <class Predicate>
207class binary_negate // deprecated in C++17
208    : public binary_function<typename Predicate::first_argument_type,
209                             typename Predicate::second_argument_type,
210                             bool>
211{
212public:
213    explicit binary_negate(const Predicate& pred);
214    bool operator()(const typename Predicate::first_argument_type& x,
215                    const typename Predicate::second_argument_type& y) const;
216};
217
218template <class Predicate> // deprecated in C++17
219binary_negate<Predicate> not2(const Predicate& pred);
220
221template <class F>
222constexpr unspecified not_fn(F&& f); // C++17, constexpr in C++20
223
224template<class T> struct is_bind_expression;
225template<class T> struct is_placeholder;
226
227    // See C++14 20.9.9, Function object binders
228template <class T> inline constexpr bool is_bind_expression_v
229  = is_bind_expression<T>::value; // C++17
230template <class T> inline constexpr int is_placeholder_v
231  = is_placeholder<T>::value; // C++17
232
233
234template<class Fn, class... BoundArgs>
235  constexpr unspecified bind(Fn&&, BoundArgs&&...);  // constexpr in C++20
236template<class R, class Fn, class... BoundArgs>
237  constexpr unspecified bind(Fn&&, BoundArgs&&...);  // constexpr in C++20
238
239template<class F, class... Args>
240 constexpr // constexpr in C++20
241 invoke_result_t<F, Args...> invoke(F&& f, Args&&... args) // C++17
242    noexcept(is_nothrow_invocable_v<F, Args...>);
243
244namespace placeholders {
245  // M is the implementation-defined number of placeholders
246  extern unspecified _1;
247  extern unspecified _2;
248  .
249  .
250  .
251  extern unspecified _Mp;
252}
253
254template <class Operation>
255class binder1st     // deprecated in C++11, removed in C++17
256    : public unary_function<typename Operation::second_argument_type,
257                            typename Operation::result_type>
258{
259protected:
260    Operation                               op;
261    typename Operation::first_argument_type value;
262public:
263    binder1st(const Operation& x, const typename Operation::first_argument_type y);
264    typename Operation::result_type operator()(      typename Operation::second_argument_type& x) const;
265    typename Operation::result_type operator()(const typename Operation::second_argument_type& x) const;
266};
267
268template <class Operation, class T>
269binder1st<Operation> bind1st(const Operation& op, const T& x);  // deprecated in C++11, removed in C++17
270
271template <class Operation>
272class binder2nd     // deprecated in C++11, removed in C++17
273    : public unary_function<typename Operation::first_argument_type,
274                            typename Operation::result_type>
275{
276protected:
277    Operation                                op;
278    typename Operation::second_argument_type value;
279public:
280    binder2nd(const Operation& x, const typename Operation::second_argument_type y);
281    typename Operation::result_type operator()(      typename Operation::first_argument_type& x) const;
282    typename Operation::result_type operator()(const typename Operation::first_argument_type& x) const;
283};
284
285template <class Operation, class T>
286binder2nd<Operation> bind2nd(const Operation& op, const T& x);  // deprecated in C++11, removed in C++17
287
288template <class Arg, class Result>      // deprecated in C++11, removed in C++17
289class pointer_to_unary_function : public unary_function<Arg, Result>
290{
291public:
292    explicit pointer_to_unary_function(Result (*f)(Arg));
293    Result operator()(Arg x) const;
294};
295
296template <class Arg, class Result>
297pointer_to_unary_function<Arg,Result> ptr_fun(Result (*f)(Arg));      // deprecated in C++11, removed in C++17
298
299template <class Arg1, class Arg2, class Result>      // deprecated in C++11, removed in C++17
300class pointer_to_binary_function : public binary_function<Arg1, Arg2, Result>
301{
302public:
303    explicit pointer_to_binary_function(Result (*f)(Arg1, Arg2));
304    Result operator()(Arg1 x, Arg2 y) const;
305};
306
307template <class Arg1, class Arg2, class Result>
308pointer_to_binary_function<Arg1,Arg2,Result> ptr_fun(Result (*f)(Arg1,Arg2));      // deprecated in C++11, removed in C++17
309
310template<class S, class T>      // deprecated in C++11, removed in C++17
311class mem_fun_t : public unary_function<T*, S>
312{
313public:
314    explicit mem_fun_t(S (T::*p)());
315    S operator()(T* p) const;
316};
317
318template<class S, class T, class A>
319class mem_fun1_t : public binary_function<T*, A, S>      // deprecated in C++11, removed in C++17
320{
321public:
322    explicit mem_fun1_t(S (T::*p)(A));
323    S operator()(T* p, A x) const;
324};
325
326template<class S, class T>          mem_fun_t<S,T>    mem_fun(S (T::*f)());      // deprecated in C++11, removed in C++17
327template<class S, class T, class A> mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A));     // deprecated in C++11, removed in C++17
328
329template<class S, class T>
330class mem_fun_ref_t : public unary_function<T, S>      // deprecated in C++11, removed in C++17
331{
332public:
333    explicit mem_fun_ref_t(S (T::*p)());
334    S operator()(T& p) const;
335};
336
337template<class S, class T, class A>
338class mem_fun1_ref_t : public binary_function<T, A, S>      // deprecated in C++11, removed in C++17
339{
340public:
341    explicit mem_fun1_ref_t(S (T::*p)(A));
342    S operator()(T& p, A x) const;
343};
344
345template<class S, class T>          mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)());      // deprecated in C++11, removed in C++17
346template<class S, class T, class A> mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A));     // deprecated in C++11, removed in C++17
347
348template <class S, class T>
349class const_mem_fun_t : public unary_function<const T*, S>      // deprecated in C++11, removed in C++17
350{
351public:
352    explicit const_mem_fun_t(S (T::*p)() const);
353    S operator()(const T* p) const;
354};
355
356template <class S, class T, class A>
357class const_mem_fun1_t : public binary_function<const T*, A, S>      // deprecated in C++11, removed in C++17
358{
359public:
360    explicit const_mem_fun1_t(S (T::*p)(A) const);
361    S operator()(const T* p, A x) const;
362};
363
364template <class S, class T>          const_mem_fun_t<S,T>    mem_fun(S (T::*f)() const);      // deprecated in C++11, removed in C++17
365template <class S, class T, class A> const_mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A) const);     // deprecated in C++11, removed in C++17
366
367template <class S, class T>
368class const_mem_fun_ref_t : public unary_function<T, S>      // deprecated in C++11, removed in C++17
369{
370public:
371    explicit const_mem_fun_ref_t(S (T::*p)() const);
372    S operator()(const T& p) const;
373};
374
375template <class S, class T, class A>
376class const_mem_fun1_ref_t : public binary_function<T, A, S>      // deprecated in C++11, removed in C++17
377{
378public:
379    explicit const_mem_fun1_ref_t(S (T::*p)(A) const);
380    S operator()(const T& p, A x) const;
381};
382
383template <class S, class T>          const_mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)() const);   // deprecated in C++11, removed in C++17
384template <class S, class T, class A> const_mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A) const);  // deprecated in C++11, removed in C++17
385
386template<class R, class T>
387constexpr unspecified mem_fn(R T::*); // constexpr in C++20
388
389class bad_function_call
390    : public exception
391{
392};
393
394template<class> class function; // undefined
395
396template<class R, class... ArgTypes>
397class function<R(ArgTypes...)>
398  : public unary_function<T1, R>      // iff sizeof...(ArgTypes) == 1 and
399                                      // ArgTypes contains T1
400  : public binary_function<T1, T2, R> // iff sizeof...(ArgTypes) == 2 and
401                                      // ArgTypes contains T1 and T2
402{
403public:
404    typedef R result_type;
405
406    // construct/copy/destroy:
407    function() noexcept;
408    function(nullptr_t) noexcept;
409    function(const function&);
410    function(function&&) noexcept;
411    template<class F>
412      function(F);
413    template<Allocator Alloc>
414      function(allocator_arg_t, const Alloc&) noexcept;            // removed in C++17
415    template<Allocator Alloc>
416      function(allocator_arg_t, const Alloc&, nullptr_t) noexcept; // removed in C++17
417    template<Allocator Alloc>
418      function(allocator_arg_t, const Alloc&, const function&);    // removed in C++17
419    template<Allocator Alloc>
420      function(allocator_arg_t, const Alloc&, function&&);         // removed in C++17
421    template<class F, Allocator Alloc>
422      function(allocator_arg_t, const Alloc&, F);                  // removed in C++17
423
424    function& operator=(const function&);
425    function& operator=(function&&) noexcept;
426    function& operator=(nullptr_t) noexcept;
427    template<class F>
428      function& operator=(F&&);
429    template<class F>
430      function& operator=(reference_wrapper<F>) noexcept;
431
432    ~function();
433
434    // function modifiers:
435    void swap(function&) noexcept;
436    template<class F, class Alloc>
437      void assign(F&&, const Alloc&);                 // Removed in C++17
438
439    // function capacity:
440    explicit operator bool() const noexcept;
441
442    // function invocation:
443    R operator()(ArgTypes...) const;
444
445    // function target access:
446    const std::type_info& target_type() const noexcept;
447    template <typename T>       T* target() noexcept;
448    template <typename T> const T* target() const noexcept;
449};
450
451// Deduction guides
452template<class R, class ...Args>
453function(R(*)(Args...)) -> function<R(Args...)>; // since C++17
454
455template<class F>
456function(F) -> function<see-below>; // since C++17
457
458// Null pointer comparisons:
459template <class R, class ... ArgTypes>
460  bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
461
462template <class R, class ... ArgTypes>
463  bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
464
465template <class R, class ... ArgTypes>
466  bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
467
468template <class  R, class ... ArgTypes>
469  bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
470
471// specialized algorithms:
472template <class  R, class ... ArgTypes>
473  void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&) noexcept;
474
475template <class T> struct hash;
476
477template <> struct hash<bool>;
478template <> struct hash<char>;
479template <> struct hash<signed char>;
480template <> struct hash<unsigned char>;
481template <> struct hash<char8_t>; // since C++20
482template <> struct hash<char16_t>;
483template <> struct hash<char32_t>;
484template <> struct hash<wchar_t>;
485template <> struct hash<short>;
486template <> struct hash<unsigned short>;
487template <> struct hash<int>;
488template <> struct hash<unsigned int>;
489template <> struct hash<long>;
490template <> struct hash<long long>;
491template <> struct hash<unsigned long>;
492template <> struct hash<unsigned long long>;
493
494template <> struct hash<float>;
495template <> struct hash<double>;
496template <> struct hash<long double>;
497
498template<class T> struct hash<T*>;
499template <> struct hash<nullptr_t>;  // C++17
500
501}  // std
502
503POLICY:  For non-variadic implementations, the number of arguments is limited
504         to 3.  It is hoped that the need for non-variadic implementations
505         will be minimal.
506
507*/
508
509#include <__config>
510#include <__debug>
511#include <concepts>
512#include <type_traits>
513#include <typeinfo>
514#include <exception>
515#include <memory>
516#include <tuple>
517#include <utility>
518#include <version>
519
520#include <__functional_base>
521
522#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
523#pragma GCC system_header
524#endif
525
526_LIBCPP_BEGIN_NAMESPACE_STD
527
528#if _LIBCPP_STD_VER > 11
529template <class _Tp = void>
530#else
531template <class _Tp>
532#endif
533struct _LIBCPP_TEMPLATE_VIS plus : binary_function<_Tp, _Tp, _Tp>
534{
535    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
536    _Tp operator()(const _Tp& __x, const _Tp& __y) const
537        {return __x + __y;}
538};
539
540#if _LIBCPP_STD_VER > 11
541template <>
542struct _LIBCPP_TEMPLATE_VIS plus<void>
543{
544    template <class _T1, class _T2>
545    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
546    auto operator()(_T1&& __t, _T2&& __u) const
547    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u)))
548    -> decltype        (_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u))
549        { return        _VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u); }
550    typedef void is_transparent;
551};
552#endif
553
554
555#if _LIBCPP_STD_VER > 11
556template <class _Tp = void>
557#else
558template <class _Tp>
559#endif
560struct _LIBCPP_TEMPLATE_VIS minus : binary_function<_Tp, _Tp, _Tp>
561{
562    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
563    _Tp operator()(const _Tp& __x, const _Tp& __y) const
564        {return __x - __y;}
565};
566
567#if _LIBCPP_STD_VER > 11
568template <>
569struct _LIBCPP_TEMPLATE_VIS minus<void>
570{
571    template <class _T1, class _T2>
572    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
573    auto operator()(_T1&& __t, _T2&& __u) const
574    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u)))
575    -> decltype        (_VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u))
576        { return        _VSTD::forward<_T1>(__t) - _VSTD::forward<_T2>(__u); }
577    typedef void is_transparent;
578};
579#endif
580
581
582#if _LIBCPP_STD_VER > 11
583template <class _Tp = void>
584#else
585template <class _Tp>
586#endif
587struct _LIBCPP_TEMPLATE_VIS multiplies : binary_function<_Tp, _Tp, _Tp>
588{
589    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
590    _Tp operator()(const _Tp& __x, const _Tp& __y) const
591        {return __x * __y;}
592};
593
594#if _LIBCPP_STD_VER > 11
595template <>
596struct _LIBCPP_TEMPLATE_VIS multiplies<void>
597{
598    template <class _T1, class _T2>
599    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
600    auto operator()(_T1&& __t, _T2&& __u) const
601    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u)))
602    -> decltype        (_VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u))
603        { return        _VSTD::forward<_T1>(__t) * _VSTD::forward<_T2>(__u); }
604    typedef void is_transparent;
605};
606#endif
607
608
609#if _LIBCPP_STD_VER > 11
610template <class _Tp = void>
611#else
612template <class _Tp>
613#endif
614struct _LIBCPP_TEMPLATE_VIS divides : binary_function<_Tp, _Tp, _Tp>
615{
616    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
617    _Tp operator()(const _Tp& __x, const _Tp& __y) const
618        {return __x / __y;}
619};
620
621#if _LIBCPP_STD_VER > 11
622template <>
623struct _LIBCPP_TEMPLATE_VIS divides<void>
624{
625    template <class _T1, class _T2>
626    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
627    auto operator()(_T1&& __t, _T2&& __u) const
628    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u)))
629    -> decltype        (_VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u))
630        { return        _VSTD::forward<_T1>(__t) / _VSTD::forward<_T2>(__u); }
631    typedef void is_transparent;
632};
633#endif
634
635
636#if _LIBCPP_STD_VER > 11
637template <class _Tp = void>
638#else
639template <class _Tp>
640#endif
641struct _LIBCPP_TEMPLATE_VIS modulus : binary_function<_Tp, _Tp, _Tp>
642{
643    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
644    _Tp operator()(const _Tp& __x, const _Tp& __y) const
645        {return __x % __y;}
646};
647
648#if _LIBCPP_STD_VER > 11
649template <>
650struct _LIBCPP_TEMPLATE_VIS modulus<void>
651{
652    template <class _T1, class _T2>
653    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
654    auto operator()(_T1&& __t, _T2&& __u) const
655    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u)))
656    -> decltype        (_VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u))
657        { return        _VSTD::forward<_T1>(__t) % _VSTD::forward<_T2>(__u); }
658    typedef void is_transparent;
659};
660#endif
661
662
663#if _LIBCPP_STD_VER > 11
664template <class _Tp = void>
665#else
666template <class _Tp>
667#endif
668struct _LIBCPP_TEMPLATE_VIS negate : unary_function<_Tp, _Tp>
669{
670    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
671    _Tp operator()(const _Tp& __x) const
672        {return -__x;}
673};
674
675#if _LIBCPP_STD_VER > 11
676template <>
677struct _LIBCPP_TEMPLATE_VIS negate<void>
678{
679    template <class _Tp>
680    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
681    auto operator()(_Tp&& __x) const
682    _NOEXCEPT_(noexcept(- _VSTD::forward<_Tp>(__x)))
683    -> decltype        (- _VSTD::forward<_Tp>(__x))
684        { return        - _VSTD::forward<_Tp>(__x); }
685    typedef void is_transparent;
686};
687#endif
688
689
690#if _LIBCPP_STD_VER > 11
691template <class _Tp = void>
692#else
693template <class _Tp>
694#endif
695struct _LIBCPP_TEMPLATE_VIS equal_to : binary_function<_Tp, _Tp, bool>
696{
697    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
698    bool operator()(const _Tp& __x, const _Tp& __y) const
699        {return __x == __y;}
700};
701
702#if _LIBCPP_STD_VER > 11
703template <>
704struct _LIBCPP_TEMPLATE_VIS equal_to<void>
705{
706    template <class _T1, class _T2>
707    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
708    auto operator()(_T1&& __t, _T2&& __u) const
709    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u)))
710    -> decltype        (_VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u))
711        { return        _VSTD::forward<_T1>(__t) == _VSTD::forward<_T2>(__u); }
712    typedef void is_transparent;
713};
714#endif
715
716
717#if _LIBCPP_STD_VER > 11
718template <class _Tp = void>
719#else
720template <class _Tp>
721#endif
722struct _LIBCPP_TEMPLATE_VIS not_equal_to : binary_function<_Tp, _Tp, bool>
723{
724    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
725    bool operator()(const _Tp& __x, const _Tp& __y) const
726        {return __x != __y;}
727};
728
729#if _LIBCPP_STD_VER > 11
730template <>
731struct _LIBCPP_TEMPLATE_VIS not_equal_to<void>
732{
733    template <class _T1, class _T2>
734    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
735    auto operator()(_T1&& __t, _T2&& __u) const
736    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u)))
737    -> decltype        (_VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u))
738        { return        _VSTD::forward<_T1>(__t) != _VSTD::forward<_T2>(__u); }
739    typedef void is_transparent;
740};
741#endif
742
743
744#if _LIBCPP_STD_VER > 11
745template <class _Tp = void>
746#else
747template <class _Tp>
748#endif
749struct _LIBCPP_TEMPLATE_VIS greater : binary_function<_Tp, _Tp, bool>
750{
751    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
752    bool operator()(const _Tp& __x, const _Tp& __y) const
753        {return __x > __y;}
754};
755
756#if _LIBCPP_STD_VER > 11
757template <>
758struct _LIBCPP_TEMPLATE_VIS greater<void>
759{
760    template <class _T1, class _T2>
761    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
762    auto operator()(_T1&& __t, _T2&& __u) const
763    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u)))
764    -> decltype        (_VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u))
765        { return        _VSTD::forward<_T1>(__t) > _VSTD::forward<_T2>(__u); }
766    typedef void is_transparent;
767};
768#endif
769
770
771// less in <__functional_base>
772
773#if _LIBCPP_STD_VER > 11
774template <class _Tp = void>
775#else
776template <class _Tp>
777#endif
778struct _LIBCPP_TEMPLATE_VIS greater_equal : binary_function<_Tp, _Tp, bool>
779{
780    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
781    bool operator()(const _Tp& __x, const _Tp& __y) const
782        {return __x >= __y;}
783};
784
785#if _LIBCPP_STD_VER > 11
786template <>
787struct _LIBCPP_TEMPLATE_VIS greater_equal<void>
788{
789    template <class _T1, class _T2>
790    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
791    auto operator()(_T1&& __t, _T2&& __u) const
792    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u)))
793    -> decltype        (_VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u))
794        { return        _VSTD::forward<_T1>(__t) >= _VSTD::forward<_T2>(__u); }
795    typedef void is_transparent;
796};
797#endif
798
799
800#if _LIBCPP_STD_VER > 11
801template <class _Tp = void>
802#else
803template <class _Tp>
804#endif
805struct _LIBCPP_TEMPLATE_VIS less_equal : binary_function<_Tp, _Tp, bool>
806{
807    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
808    bool operator()(const _Tp& __x, const _Tp& __y) const
809        {return __x <= __y;}
810};
811
812#if _LIBCPP_STD_VER > 11
813template <>
814struct _LIBCPP_TEMPLATE_VIS less_equal<void>
815{
816    template <class _T1, class _T2>
817    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
818    auto operator()(_T1&& __t, _T2&& __u) const
819    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u)))
820    -> decltype        (_VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u))
821        { return        _VSTD::forward<_T1>(__t) <= _VSTD::forward<_T2>(__u); }
822    typedef void is_transparent;
823};
824#endif
825
826
827#if _LIBCPP_STD_VER > 11
828template <class _Tp = void>
829#else
830template <class _Tp>
831#endif
832struct _LIBCPP_TEMPLATE_VIS logical_and : binary_function<_Tp, _Tp, bool>
833{
834    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
835    bool operator()(const _Tp& __x, const _Tp& __y) const
836        {return __x && __y;}
837};
838
839#if _LIBCPP_STD_VER > 11
840template <>
841struct _LIBCPP_TEMPLATE_VIS logical_and<void>
842{
843    template <class _T1, class _T2>
844    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
845    auto operator()(_T1&& __t, _T2&& __u) const
846    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u)))
847    -> decltype        (_VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u))
848        { return        _VSTD::forward<_T1>(__t) && _VSTD::forward<_T2>(__u); }
849    typedef void is_transparent;
850};
851#endif
852
853
854#if _LIBCPP_STD_VER > 11
855template <class _Tp = void>
856#else
857template <class _Tp>
858#endif
859struct _LIBCPP_TEMPLATE_VIS logical_or : binary_function<_Tp, _Tp, bool>
860{
861    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
862    bool operator()(const _Tp& __x, const _Tp& __y) const
863        {return __x || __y;}
864};
865
866#if _LIBCPP_STD_VER > 11
867template <>
868struct _LIBCPP_TEMPLATE_VIS logical_or<void>
869{
870    template <class _T1, class _T2>
871    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
872    auto operator()(_T1&& __t, _T2&& __u) const
873    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u)))
874    -> decltype        (_VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u))
875        { return        _VSTD::forward<_T1>(__t) || _VSTD::forward<_T2>(__u); }
876    typedef void is_transparent;
877};
878#endif
879
880
881#if _LIBCPP_STD_VER > 11
882template <class _Tp = void>
883#else
884template <class _Tp>
885#endif
886struct _LIBCPP_TEMPLATE_VIS logical_not : unary_function<_Tp, bool>
887{
888    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
889    bool operator()(const _Tp& __x) const
890        {return !__x;}
891};
892
893#if _LIBCPP_STD_VER > 11
894template <>
895struct _LIBCPP_TEMPLATE_VIS logical_not<void>
896{
897    template <class _Tp>
898    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
899    auto operator()(_Tp&& __x) const
900    _NOEXCEPT_(noexcept(!_VSTD::forward<_Tp>(__x)))
901    -> decltype        (!_VSTD::forward<_Tp>(__x))
902        { return        !_VSTD::forward<_Tp>(__x); }
903    typedef void is_transparent;
904};
905#endif
906
907
908#if _LIBCPP_STD_VER > 11
909template <class _Tp = void>
910#else
911template <class _Tp>
912#endif
913struct _LIBCPP_TEMPLATE_VIS bit_and : binary_function<_Tp, _Tp, _Tp>
914{
915    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
916    _Tp operator()(const _Tp& __x, const _Tp& __y) const
917        {return __x & __y;}
918};
919
920#if _LIBCPP_STD_VER > 11
921template <>
922struct _LIBCPP_TEMPLATE_VIS bit_and<void>
923{
924    template <class _T1, class _T2>
925    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
926    auto operator()(_T1&& __t, _T2&& __u) const
927    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u)))
928    -> decltype        (_VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u))
929        { return        _VSTD::forward<_T1>(__t) & _VSTD::forward<_T2>(__u); }
930    typedef void is_transparent;
931};
932#endif
933
934
935#if _LIBCPP_STD_VER > 11
936template <class _Tp = void>
937#else
938template <class _Tp>
939#endif
940struct _LIBCPP_TEMPLATE_VIS bit_or : binary_function<_Tp, _Tp, _Tp>
941{
942    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
943    _Tp operator()(const _Tp& __x, const _Tp& __y) const
944        {return __x | __y;}
945};
946
947#if _LIBCPP_STD_VER > 11
948template <>
949struct _LIBCPP_TEMPLATE_VIS bit_or<void>
950{
951    template <class _T1, class _T2>
952    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
953    auto operator()(_T1&& __t, _T2&& __u) const
954    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u)))
955    -> decltype        (_VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u))
956        { return        _VSTD::forward<_T1>(__t) | _VSTD::forward<_T2>(__u); }
957    typedef void is_transparent;
958};
959#endif
960
961
962#if _LIBCPP_STD_VER > 11
963template <class _Tp = void>
964#else
965template <class _Tp>
966#endif
967struct _LIBCPP_TEMPLATE_VIS bit_xor : binary_function<_Tp, _Tp, _Tp>
968{
969    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
970    _Tp operator()(const _Tp& __x, const _Tp& __y) const
971        {return __x ^ __y;}
972};
973
974#if _LIBCPP_STD_VER > 11
975template <>
976struct _LIBCPP_TEMPLATE_VIS bit_xor<void>
977{
978    template <class _T1, class _T2>
979    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
980    auto operator()(_T1&& __t, _T2&& __u) const
981    _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u)))
982    -> decltype        (_VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u))
983        { return        _VSTD::forward<_T1>(__t) ^ _VSTD::forward<_T2>(__u); }
984    typedef void is_transparent;
985};
986#endif
987
988
989#if _LIBCPP_STD_VER > 11
990template <class _Tp = void>
991struct _LIBCPP_TEMPLATE_VIS bit_not : unary_function<_Tp, _Tp>
992{
993    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
994    _Tp operator()(const _Tp& __x) const
995        {return ~__x;}
996};
997
998template <>
999struct _LIBCPP_TEMPLATE_VIS bit_not<void>
1000{
1001    template <class _Tp>
1002    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1003    auto operator()(_Tp&& __x) const
1004    _NOEXCEPT_(noexcept(~_VSTD::forward<_Tp>(__x)))
1005    -> decltype        (~_VSTD::forward<_Tp>(__x))
1006        { return        ~_VSTD::forward<_Tp>(__x); }
1007    typedef void is_transparent;
1008};
1009#endif
1010
1011template <class _Predicate>
1012class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 unary_negate
1013    : public unary_function<typename _Predicate::argument_type, bool>
1014{
1015    _Predicate __pred_;
1016public:
1017    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1018    explicit unary_negate(const _Predicate& __pred)
1019        : __pred_(__pred) {}
1020    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1021    bool operator()(const typename _Predicate::argument_type& __x) const
1022        {return !__pred_(__x);}
1023};
1024
1025template <class _Predicate>
1026_LIBCPP_DEPRECATED_IN_CXX17 inline _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1027unary_negate<_Predicate>
1028not1(const _Predicate& __pred) {return unary_negate<_Predicate>(__pred);}
1029
1030template <class _Predicate>
1031class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 binary_negate
1032    : public binary_function<typename _Predicate::first_argument_type,
1033                             typename _Predicate::second_argument_type,
1034                             bool>
1035{
1036    _Predicate __pred_;
1037public:
1038    _LIBCPP_INLINE_VISIBILITY explicit _LIBCPP_CONSTEXPR_AFTER_CXX11
1039    binary_negate(const _Predicate& __pred) : __pred_(__pred) {}
1040
1041    _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1042    bool operator()(const typename _Predicate::first_argument_type& __x,
1043                    const typename _Predicate::second_argument_type& __y) const
1044        {return !__pred_(__x, __y);}
1045};
1046
1047template <class _Predicate>
1048_LIBCPP_DEPRECATED_IN_CXX17 inline _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
1049binary_negate<_Predicate>
1050not2(const _Predicate& __pred) {return binary_negate<_Predicate>(__pred);}
1051
1052#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_BINDERS)
1053template <class __Operation>
1054class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 binder1st
1055    : public unary_function<typename __Operation::second_argument_type,
1056                            typename __Operation::result_type>
1057{
1058protected:
1059    __Operation                               op;
1060    typename __Operation::first_argument_type value;
1061public:
1062    _LIBCPP_INLINE_VISIBILITY binder1st(const __Operation& __x,
1063                               const typename __Operation::first_argument_type __y)
1064        : op(__x), value(__y) {}
1065    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1066        (typename __Operation::second_argument_type& __x) const
1067            {return op(value, __x);}
1068    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1069        (const typename __Operation::second_argument_type& __x) const
1070            {return op(value, __x);}
1071};
1072
1073template <class __Operation, class _Tp>
1074_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1075binder1st<__Operation>
1076bind1st(const __Operation& __op, const _Tp& __x)
1077    {return binder1st<__Operation>(__op, __x);}
1078
1079template <class __Operation>
1080class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 binder2nd
1081    : public unary_function<typename __Operation::first_argument_type,
1082                            typename __Operation::result_type>
1083{
1084protected:
1085    __Operation                                op;
1086    typename __Operation::second_argument_type value;
1087public:
1088    _LIBCPP_INLINE_VISIBILITY
1089    binder2nd(const __Operation& __x, const typename __Operation::second_argument_type __y)
1090        : op(__x), value(__y) {}
1091    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1092        (      typename __Operation::first_argument_type& __x) const
1093            {return op(__x, value);}
1094    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
1095        (const typename __Operation::first_argument_type& __x) const
1096            {return op(__x, value);}
1097};
1098
1099template <class __Operation, class _Tp>
1100_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1101binder2nd<__Operation>
1102bind2nd(const __Operation& __op, const _Tp& __x)
1103    {return binder2nd<__Operation>(__op, __x);}
1104
1105template <class _Arg, class _Result>
1106class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 pointer_to_unary_function
1107    : public unary_function<_Arg, _Result>
1108{
1109    _Result (*__f_)(_Arg);
1110public:
1111    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_unary_function(_Result (*__f)(_Arg))
1112        : __f_(__f) {}
1113    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg __x) const
1114        {return __f_(__x);}
1115};
1116
1117template <class _Arg, class _Result>
1118_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1119pointer_to_unary_function<_Arg,_Result>
1120ptr_fun(_Result (*__f)(_Arg))
1121    {return pointer_to_unary_function<_Arg,_Result>(__f);}
1122
1123template <class _Arg1, class _Arg2, class _Result>
1124class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 pointer_to_binary_function
1125    : public binary_function<_Arg1, _Arg2, _Result>
1126{
1127    _Result (*__f_)(_Arg1, _Arg2);
1128public:
1129    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_binary_function(_Result (*__f)(_Arg1, _Arg2))
1130        : __f_(__f) {}
1131    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg1 __x, _Arg2 __y) const
1132        {return __f_(__x, __y);}
1133};
1134
1135template <class _Arg1, class _Arg2, class _Result>
1136_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1137pointer_to_binary_function<_Arg1,_Arg2,_Result>
1138ptr_fun(_Result (*__f)(_Arg1,_Arg2))
1139    {return pointer_to_binary_function<_Arg1,_Arg2,_Result>(__f);}
1140
1141template<class _Sp, class _Tp>
1142class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun_t
1143    : public unary_function<_Tp*, _Sp>
1144{
1145    _Sp (_Tp::*__p_)();
1146public:
1147    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_t(_Sp (_Tp::*__p)())
1148        : __p_(__p) {}
1149    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p) const
1150        {return (__p->*__p_)();}
1151};
1152
1153template<class _Sp, class _Tp, class _Ap>
1154class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun1_t
1155    : public binary_function<_Tp*, _Ap, _Sp>
1156{
1157    _Sp (_Tp::*__p_)(_Ap);
1158public:
1159    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_t(_Sp (_Tp::*__p)(_Ap))
1160        : __p_(__p) {}
1161    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p, _Ap __x) const
1162        {return (__p->*__p_)(__x);}
1163};
1164
1165template<class _Sp, class _Tp>
1166_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1167mem_fun_t<_Sp,_Tp>
1168mem_fun(_Sp (_Tp::*__f)())
1169    {return mem_fun_t<_Sp,_Tp>(__f);}
1170
1171template<class _Sp, class _Tp, class _Ap>
1172_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1173mem_fun1_t<_Sp,_Tp,_Ap>
1174mem_fun(_Sp (_Tp::*__f)(_Ap))
1175    {return mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
1176
1177template<class _Sp, class _Tp>
1178class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun_ref_t
1179    : public unary_function<_Tp, _Sp>
1180{
1181    _Sp (_Tp::*__p_)();
1182public:
1183    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_ref_t(_Sp (_Tp::*__p)())
1184        : __p_(__p) {}
1185    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p) const
1186        {return (__p.*__p_)();}
1187};
1188
1189template<class _Sp, class _Tp, class _Ap>
1190class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 mem_fun1_ref_t
1191    : public binary_function<_Tp, _Ap, _Sp>
1192{
1193    _Sp (_Tp::*__p_)(_Ap);
1194public:
1195    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap))
1196        : __p_(__p) {}
1197    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p, _Ap __x) const
1198        {return (__p.*__p_)(__x);}
1199};
1200
1201template<class _Sp, class _Tp>
1202_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1203mem_fun_ref_t<_Sp,_Tp>
1204mem_fun_ref(_Sp (_Tp::*__f)())
1205    {return mem_fun_ref_t<_Sp,_Tp>(__f);}
1206
1207template<class _Sp, class _Tp, class _Ap>
1208_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1209mem_fun1_ref_t<_Sp,_Tp,_Ap>
1210mem_fun_ref(_Sp (_Tp::*__f)(_Ap))
1211    {return mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
1212
1213template <class _Sp, class _Tp>
1214class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun_t
1215    : public unary_function<const _Tp*, _Sp>
1216{
1217    _Sp (_Tp::*__p_)() const;
1218public:
1219    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_t(_Sp (_Tp::*__p)() const)
1220        : __p_(__p) {}
1221    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p) const
1222        {return (__p->*__p_)();}
1223};
1224
1225template <class _Sp, class _Tp, class _Ap>
1226class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun1_t
1227    : public binary_function<const _Tp*, _Ap, _Sp>
1228{
1229    _Sp (_Tp::*__p_)(_Ap) const;
1230public:
1231    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_t(_Sp (_Tp::*__p)(_Ap) const)
1232        : __p_(__p) {}
1233    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p, _Ap __x) const
1234        {return (__p->*__p_)(__x);}
1235};
1236
1237template <class _Sp, class _Tp>
1238_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1239const_mem_fun_t<_Sp,_Tp>
1240mem_fun(_Sp (_Tp::*__f)() const)
1241    {return const_mem_fun_t<_Sp,_Tp>(__f);}
1242
1243template <class _Sp, class _Tp, class _Ap>
1244_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1245const_mem_fun1_t<_Sp,_Tp,_Ap>
1246mem_fun(_Sp (_Tp::*__f)(_Ap) const)
1247    {return const_mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
1248
1249template <class _Sp, class _Tp>
1250class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun_ref_t
1251    : public unary_function<_Tp, _Sp>
1252{
1253    _Sp (_Tp::*__p_)() const;
1254public:
1255    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_ref_t(_Sp (_Tp::*__p)() const)
1256        : __p_(__p) {}
1257    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p) const
1258        {return (__p.*__p_)();}
1259};
1260
1261template <class _Sp, class _Tp, class _Ap>
1262class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 const_mem_fun1_ref_t
1263    : public binary_function<_Tp, _Ap, _Sp>
1264{
1265    _Sp (_Tp::*__p_)(_Ap) const;
1266public:
1267    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap) const)
1268        : __p_(__p) {}
1269    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p, _Ap __x) const
1270        {return (__p.*__p_)(__x);}
1271};
1272
1273template <class _Sp, class _Tp>
1274_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1275const_mem_fun_ref_t<_Sp,_Tp>
1276mem_fun_ref(_Sp (_Tp::*__f)() const)
1277    {return const_mem_fun_ref_t<_Sp,_Tp>(__f);}
1278
1279template <class _Sp, class _Tp, class _Ap>
1280_LIBCPP_DEPRECATED_IN_CXX11 inline _LIBCPP_INLINE_VISIBILITY
1281const_mem_fun1_ref_t<_Sp,_Tp,_Ap>
1282mem_fun_ref(_Sp (_Tp::*__f)(_Ap) const)
1283    {return const_mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
1284#endif
1285
1286////////////////////////////////////////////////////////////////////////////////
1287//                                MEMFUN
1288//==============================================================================
1289
1290template <class _Tp>
1291class __mem_fn
1292    : public __weak_result_type<_Tp>
1293{
1294public:
1295    // types
1296    typedef _Tp type;
1297private:
1298    type __f_;
1299
1300public:
1301    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1302    __mem_fn(type __f) _NOEXCEPT : __f_(__f) {}
1303
1304#ifndef _LIBCPP_CXX03_LANG
1305    // invoke
1306    template <class... _ArgTypes>
1307    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1308    typename __invoke_return<type, _ArgTypes...>::type
1309    operator() (_ArgTypes&&... __args) const {
1310        return _VSTD::__invoke(__f_, _VSTD::forward<_ArgTypes>(__args)...);
1311    }
1312#else
1313
1314    template <class _A0>
1315    _LIBCPP_INLINE_VISIBILITY
1316    typename __invoke_return0<type, _A0>::type
1317    operator() (_A0& __a0) const {
1318        return _VSTD::__invoke(__f_, __a0);
1319    }
1320
1321    template <class _A0>
1322    _LIBCPP_INLINE_VISIBILITY
1323    typename __invoke_return0<type, _A0 const>::type
1324    operator() (_A0 const& __a0) const {
1325        return _VSTD::__invoke(__f_, __a0);
1326    }
1327
1328    template <class _A0, class _A1>
1329    _LIBCPP_INLINE_VISIBILITY
1330    typename __invoke_return1<type, _A0, _A1>::type
1331    operator() (_A0& __a0, _A1& __a1) const {
1332        return _VSTD::__invoke(__f_, __a0, __a1);
1333    }
1334
1335    template <class _A0, class _A1>
1336    _LIBCPP_INLINE_VISIBILITY
1337    typename __invoke_return1<type, _A0 const, _A1>::type
1338    operator() (_A0 const& __a0, _A1& __a1) const {
1339        return _VSTD::__invoke(__f_, __a0, __a1);
1340    }
1341
1342    template <class _A0, class _A1>
1343    _LIBCPP_INLINE_VISIBILITY
1344    typename __invoke_return1<type, _A0, _A1 const>::type
1345    operator() (_A0& __a0, _A1 const& __a1) const {
1346        return _VSTD::__invoke(__f_, __a0, __a1);
1347    }
1348
1349    template <class _A0, class _A1>
1350    _LIBCPP_INLINE_VISIBILITY
1351    typename __invoke_return1<type, _A0 const, _A1 const>::type
1352    operator() (_A0 const& __a0, _A1 const& __a1) const {
1353        return _VSTD::__invoke(__f_, __a0, __a1);
1354    }
1355
1356    template <class _A0, class _A1, class _A2>
1357    _LIBCPP_INLINE_VISIBILITY
1358    typename __invoke_return2<type, _A0, _A1, _A2>::type
1359    operator() (_A0& __a0, _A1& __a1, _A2& __a2) const {
1360        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1361    }
1362
1363    template <class _A0, class _A1, class _A2>
1364    _LIBCPP_INLINE_VISIBILITY
1365    typename __invoke_return2<type, _A0 const, _A1, _A2>::type
1366    operator() (_A0 const& __a0, _A1& __a1, _A2& __a2) const {
1367        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1368    }
1369
1370    template <class _A0, class _A1, class _A2>
1371    _LIBCPP_INLINE_VISIBILITY
1372    typename __invoke_return2<type, _A0, _A1 const, _A2>::type
1373    operator() (_A0& __a0, _A1 const& __a1, _A2& __a2) const {
1374        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1375    }
1376
1377    template <class _A0, class _A1, class _A2>
1378    _LIBCPP_INLINE_VISIBILITY
1379    typename __invoke_return2<type, _A0, _A1, _A2 const>::type
1380    operator() (_A0& __a0, _A1& __a1, _A2 const& __a2) const {
1381        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1382    }
1383
1384    template <class _A0, class _A1, class _A2>
1385    _LIBCPP_INLINE_VISIBILITY
1386    typename __invoke_return2<type, _A0 const, _A1 const, _A2>::type
1387    operator() (_A0 const& __a0, _A1 const& __a1, _A2& __a2) const {
1388        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1389    }
1390
1391    template <class _A0, class _A1, class _A2>
1392    _LIBCPP_INLINE_VISIBILITY
1393    typename __invoke_return2<type, _A0 const, _A1, _A2 const>::type
1394    operator() (_A0 const& __a0, _A1& __a1, _A2 const& __a2) const {
1395        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1396    }
1397
1398    template <class _A0, class _A1, class _A2>
1399    _LIBCPP_INLINE_VISIBILITY
1400    typename __invoke_return2<type, _A0, _A1 const, _A2 const>::type
1401    operator() (_A0& __a0, _A1 const& __a1, _A2 const& __a2) const {
1402        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1403    }
1404
1405    template <class _A0, class _A1, class _A2>
1406    _LIBCPP_INLINE_VISIBILITY
1407    typename __invoke_return2<type, _A0 const, _A1 const, _A2 const>::type
1408    operator() (_A0 const& __a0, _A1 const& __a1, _A2 const& __a2) const {
1409        return _VSTD::__invoke(__f_, __a0, __a1, __a2);
1410    }
1411#endif
1412};
1413
1414template<class _Rp, class _Tp>
1415inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1416__mem_fn<_Rp _Tp::*>
1417mem_fn(_Rp _Tp::* __pm) _NOEXCEPT
1418{
1419    return __mem_fn<_Rp _Tp::*>(__pm);
1420}
1421
1422////////////////////////////////////////////////////////////////////////////////
1423//                                FUNCTION
1424//==============================================================================
1425
1426// bad_function_call
1427
1428class _LIBCPP_EXCEPTION_ABI bad_function_call
1429    : public exception
1430{
1431#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
1432public:
1433    virtual ~bad_function_call() _NOEXCEPT;
1434
1435    virtual const char* what() const _NOEXCEPT;
1436#endif
1437};
1438
1439_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
1440void __throw_bad_function_call()
1441{
1442#ifndef _LIBCPP_NO_EXCEPTIONS
1443    throw bad_function_call();
1444#else
1445    _VSTD::abort();
1446#endif
1447}
1448
1449#if defined(_LIBCPP_CXX03_LANG) && !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS) && __has_attribute(deprecated)
1450#   define _LIBCPP_DEPRECATED_CXX03_FUNCTION \
1451        __attribute__((deprecated("Using std::function in C++03 is not supported anymore. Please upgrade to C++11 or later, or use a different type")))
1452#else
1453#   define _LIBCPP_DEPRECATED_CXX03_FUNCTION /* nothing */
1454#endif
1455
1456template<class _Fp> class _LIBCPP_DEPRECATED_CXX03_FUNCTION _LIBCPP_TEMPLATE_VIS function; // undefined
1457
1458namespace __function
1459{
1460
1461template<class _Rp>
1462struct __maybe_derive_from_unary_function
1463{
1464};
1465
1466template<class _Rp, class _A1>
1467struct __maybe_derive_from_unary_function<_Rp(_A1)>
1468    : public unary_function<_A1, _Rp>
1469{
1470};
1471
1472template<class _Rp>
1473struct __maybe_derive_from_binary_function
1474{
1475};
1476
1477template<class _Rp, class _A1, class _A2>
1478struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)>
1479    : public binary_function<_A1, _A2, _Rp>
1480{
1481};
1482
1483template <class _Fp>
1484_LIBCPP_INLINE_VISIBILITY
1485bool __not_null(_Fp const&) { return true; }
1486
1487template <class _Fp>
1488_LIBCPP_INLINE_VISIBILITY
1489bool __not_null(_Fp* __ptr) { return __ptr; }
1490
1491template <class _Ret, class _Class>
1492_LIBCPP_INLINE_VISIBILITY
1493bool __not_null(_Ret _Class::*__ptr) { return __ptr; }
1494
1495template <class _Fp>
1496_LIBCPP_INLINE_VISIBILITY
1497bool __not_null(function<_Fp> const& __f) { return !!__f; }
1498
1499#ifdef _LIBCPP_HAS_EXTENSION_BLOCKS
1500template <class _Rp, class ..._Args>
1501_LIBCPP_INLINE_VISIBILITY
1502bool __not_null(_Rp (^__p)(_Args...)) { return __p; }
1503#endif
1504
1505} // namespace __function
1506
1507#ifndef _LIBCPP_CXX03_LANG
1508
1509namespace __function {
1510
1511// __alloc_func holds a functor and an allocator.
1512
1513template <class _Fp, class _Ap, class _FB> class __alloc_func;
1514template <class _Fp, class _FB>
1515class __default_alloc_func;
1516
1517template <class _Fp, class _Ap, class _Rp, class... _ArgTypes>
1518class __alloc_func<_Fp, _Ap, _Rp(_ArgTypes...)>
1519{
1520    __compressed_pair<_Fp, _Ap> __f_;
1521
1522  public:
1523    typedef _LIBCPP_NODEBUG_TYPE _Fp _Target;
1524    typedef _LIBCPP_NODEBUG_TYPE _Ap _Alloc;
1525
1526    _LIBCPP_INLINE_VISIBILITY
1527    const _Target& __target() const { return __f_.first(); }
1528
1529    // WIN32 APIs may define __allocator, so use __get_allocator instead.
1530    _LIBCPP_INLINE_VISIBILITY
1531    const _Alloc& __get_allocator() const { return __f_.second(); }
1532
1533    _LIBCPP_INLINE_VISIBILITY
1534    explicit __alloc_func(_Target&& __f)
1535        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
1536               _VSTD::forward_as_tuple())
1537    {
1538    }
1539
1540    _LIBCPP_INLINE_VISIBILITY
1541    explicit __alloc_func(const _Target& __f, const _Alloc& __a)
1542        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
1543               _VSTD::forward_as_tuple(__a))
1544    {
1545    }
1546
1547    _LIBCPP_INLINE_VISIBILITY
1548    explicit __alloc_func(const _Target& __f, _Alloc&& __a)
1549        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
1550               _VSTD::forward_as_tuple(_VSTD::move(__a)))
1551    {
1552    }
1553
1554    _LIBCPP_INLINE_VISIBILITY
1555    explicit __alloc_func(_Target&& __f, _Alloc&& __a)
1556        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
1557               _VSTD::forward_as_tuple(_VSTD::move(__a)))
1558    {
1559    }
1560
1561    _LIBCPP_INLINE_VISIBILITY
1562    _Rp operator()(_ArgTypes&&... __arg)
1563    {
1564        typedef __invoke_void_return_wrapper<_Rp> _Invoker;
1565        return _Invoker::__call(__f_.first(),
1566                                _VSTD::forward<_ArgTypes>(__arg)...);
1567    }
1568
1569    _LIBCPP_INLINE_VISIBILITY
1570    __alloc_func* __clone() const
1571    {
1572        typedef allocator_traits<_Alloc> __alloc_traits;
1573        typedef
1574            typename __rebind_alloc_helper<__alloc_traits, __alloc_func>::type
1575                _AA;
1576        _AA __a(__f_.second());
1577        typedef __allocator_destructor<_AA> _Dp;
1578        unique_ptr<__alloc_func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1579        ::new ((void*)__hold.get()) __alloc_func(__f_.first(), _Alloc(__a));
1580        return __hold.release();
1581    }
1582
1583    _LIBCPP_INLINE_VISIBILITY
1584    void destroy() _NOEXCEPT { __f_.~__compressed_pair<_Target, _Alloc>(); }
1585
1586    static void __destroy_and_delete(__alloc_func* __f) {
1587      typedef allocator_traits<_Alloc> __alloc_traits;
1588      typedef typename __rebind_alloc_helper<__alloc_traits, __alloc_func>::type
1589          _FunAlloc;
1590      _FunAlloc __a(__f->__get_allocator());
1591      __f->destroy();
1592      __a.deallocate(__f, 1);
1593    }
1594};
1595
1596template <class _Fp, class _Rp, class... _ArgTypes>
1597class __default_alloc_func<_Fp, _Rp(_ArgTypes...)> {
1598  _Fp __f_;
1599
1600public:
1601  typedef _LIBCPP_NODEBUG_TYPE _Fp _Target;
1602
1603  _LIBCPP_INLINE_VISIBILITY
1604  const _Target& __target() const { return __f_; }
1605
1606  _LIBCPP_INLINE_VISIBILITY
1607  explicit __default_alloc_func(_Target&& __f) : __f_(_VSTD::move(__f)) {}
1608
1609  _LIBCPP_INLINE_VISIBILITY
1610  explicit __default_alloc_func(const _Target& __f) : __f_(__f) {}
1611
1612  _LIBCPP_INLINE_VISIBILITY
1613  _Rp operator()(_ArgTypes&&... __arg) {
1614    typedef __invoke_void_return_wrapper<_Rp> _Invoker;
1615    return _Invoker::__call(__f_, _VSTD::forward<_ArgTypes>(__arg)...);
1616  }
1617
1618  _LIBCPP_INLINE_VISIBILITY
1619  __default_alloc_func* __clone() const {
1620      __builtin_new_allocator::__holder_t __hold =
1621        __builtin_new_allocator::__allocate_type<__default_alloc_func>(1);
1622    __default_alloc_func* __res =
1623        ::new ((void*)__hold.get()) __default_alloc_func(__f_);
1624    (void)__hold.release();
1625    return __res;
1626  }
1627
1628  _LIBCPP_INLINE_VISIBILITY
1629  void destroy() _NOEXCEPT { __f_.~_Target(); }
1630
1631  static void __destroy_and_delete(__default_alloc_func* __f) {
1632    __f->destroy();
1633      __builtin_new_allocator::__deallocate_type<__default_alloc_func>(__f, 1);
1634  }
1635};
1636
1637// __base provides an abstract interface for copyable functors.
1638
1639template<class _Fp> class _LIBCPP_TEMPLATE_VIS __base;
1640
1641template<class _Rp, class ..._ArgTypes>
1642class __base<_Rp(_ArgTypes...)>
1643{
1644    __base(const __base&);
1645    __base& operator=(const __base&);
1646public:
1647    _LIBCPP_INLINE_VISIBILITY __base() {}
1648    _LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
1649    virtual __base* __clone() const = 0;
1650    virtual void __clone(__base*) const = 0;
1651    virtual void destroy() _NOEXCEPT = 0;
1652    virtual void destroy_deallocate() _NOEXCEPT = 0;
1653    virtual _Rp operator()(_ArgTypes&& ...) = 0;
1654#ifndef _LIBCPP_NO_RTTI
1655    virtual const void* target(const type_info&) const _NOEXCEPT = 0;
1656    virtual const std::type_info& target_type() const _NOEXCEPT = 0;
1657#endif // _LIBCPP_NO_RTTI
1658};
1659
1660// __func implements __base for a given functor type.
1661
1662template<class _FD, class _Alloc, class _FB> class __func;
1663
1664template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1665class __func<_Fp, _Alloc, _Rp(_ArgTypes...)>
1666    : public  __base<_Rp(_ArgTypes...)>
1667{
1668    __alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> __f_;
1669public:
1670    _LIBCPP_INLINE_VISIBILITY
1671    explicit __func(_Fp&& __f)
1672        : __f_(_VSTD::move(__f)) {}
1673
1674    _LIBCPP_INLINE_VISIBILITY
1675    explicit __func(const _Fp& __f, const _Alloc& __a)
1676        : __f_(__f, __a) {}
1677
1678    _LIBCPP_INLINE_VISIBILITY
1679    explicit __func(const _Fp& __f, _Alloc&& __a)
1680        : __f_(__f, _VSTD::move(__a)) {}
1681
1682    _LIBCPP_INLINE_VISIBILITY
1683    explicit __func(_Fp&& __f, _Alloc&& __a)
1684        : __f_(_VSTD::move(__f), _VSTD::move(__a)) {}
1685
1686    virtual __base<_Rp(_ArgTypes...)>* __clone() const;
1687    virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
1688    virtual void destroy() _NOEXCEPT;
1689    virtual void destroy_deallocate() _NOEXCEPT;
1690    virtual _Rp operator()(_ArgTypes&&... __arg);
1691#ifndef _LIBCPP_NO_RTTI
1692    virtual const void* target(const type_info&) const _NOEXCEPT;
1693    virtual const std::type_info& target_type() const _NOEXCEPT;
1694#endif // _LIBCPP_NO_RTTI
1695};
1696
1697template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1698__base<_Rp(_ArgTypes...)>*
1699__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone() const
1700{
1701    typedef allocator_traits<_Alloc> __alloc_traits;
1702    typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
1703    _Ap __a(__f_.__get_allocator());
1704    typedef __allocator_destructor<_Ap> _Dp;
1705    unique_ptr<__func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1706    ::new ((void*)__hold.get()) __func(__f_.__target(), _Alloc(__a));
1707    return __hold.release();
1708}
1709
1710template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1711void
1712__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const
1713{
1714    ::new ((void*)__p) __func(__f_.__target(), __f_.__get_allocator());
1715}
1716
1717template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1718void
1719__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() _NOEXCEPT
1720{
1721    __f_.destroy();
1722}
1723
1724template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1725void
1726__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() _NOEXCEPT
1727{
1728    typedef allocator_traits<_Alloc> __alloc_traits;
1729    typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
1730    _Ap __a(__f_.__get_allocator());
1731    __f_.destroy();
1732    __a.deallocate(this, 1);
1733}
1734
1735template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1736_Rp
1737__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
1738{
1739    return __f_(_VSTD::forward<_ArgTypes>(__arg)...);
1740}
1741
1742#ifndef _LIBCPP_NO_RTTI
1743
1744template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1745const void*
1746__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target(const type_info& __ti) const _NOEXCEPT
1747{
1748    if (__ti == typeid(_Fp))
1749        return &__f_.__target();
1750    return nullptr;
1751}
1752
1753template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1754const std::type_info&
1755__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
1756{
1757    return typeid(_Fp);
1758}
1759
1760#endif // _LIBCPP_NO_RTTI
1761
1762// __value_func creates a value-type from a __func.
1763
1764template <class _Fp> class __value_func;
1765
1766template <class _Rp, class... _ArgTypes> class __value_func<_Rp(_ArgTypes...)>
1767{
1768    typename aligned_storage<3 * sizeof(void*)>::type __buf_;
1769
1770    typedef __base<_Rp(_ArgTypes...)> __func;
1771    __func* __f_;
1772
1773    _LIBCPP_NO_CFI static __func* __as_base(void* p)
1774    {
1775        return reinterpret_cast<__func*>(p);
1776    }
1777
1778  public:
1779    _LIBCPP_INLINE_VISIBILITY
1780    __value_func() _NOEXCEPT : __f_(nullptr) {}
1781
1782    template <class _Fp, class _Alloc>
1783    _LIBCPP_INLINE_VISIBILITY __value_func(_Fp&& __f, const _Alloc& __a)
1784        : __f_(nullptr)
1785    {
1786        typedef allocator_traits<_Alloc> __alloc_traits;
1787        typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
1788        typedef typename __rebind_alloc_helper<__alloc_traits, _Fun>::type
1789            _FunAlloc;
1790
1791        if (__function::__not_null(__f))
1792        {
1793            _FunAlloc __af(__a);
1794            if (sizeof(_Fun) <= sizeof(__buf_) &&
1795                is_nothrow_copy_constructible<_Fp>::value &&
1796                is_nothrow_copy_constructible<_FunAlloc>::value)
1797            {
1798                __f_ =
1799                    ::new ((void*)&__buf_) _Fun(_VSTD::move(__f), _Alloc(__af));
1800            }
1801            else
1802            {
1803                typedef __allocator_destructor<_FunAlloc> _Dp;
1804                unique_ptr<__func, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
1805                ::new ((void*)__hold.get()) _Fun(_VSTD::move(__f), _Alloc(__a));
1806                __f_ = __hold.release();
1807            }
1808        }
1809    }
1810
1811    template <class _Fp,
1812        class = typename enable_if<!is_same<typename decay<_Fp>::type, __value_func>::value>::type>
1813    _LIBCPP_INLINE_VISIBILITY explicit __value_func(_Fp&& __f)
1814        : __value_func(_VSTD::forward<_Fp>(__f), allocator<_Fp>()) {}
1815
1816    _LIBCPP_INLINE_VISIBILITY
1817    __value_func(const __value_func& __f)
1818    {
1819        if (__f.__f_ == nullptr)
1820            __f_ = nullptr;
1821        else if ((void*)__f.__f_ == &__f.__buf_)
1822        {
1823            __f_ = __as_base(&__buf_);
1824            __f.__f_->__clone(__f_);
1825        }
1826        else
1827            __f_ = __f.__f_->__clone();
1828    }
1829
1830    _LIBCPP_INLINE_VISIBILITY
1831    __value_func(__value_func&& __f) _NOEXCEPT
1832    {
1833        if (__f.__f_ == nullptr)
1834            __f_ = nullptr;
1835        else if ((void*)__f.__f_ == &__f.__buf_)
1836        {
1837            __f_ = __as_base(&__buf_);
1838            __f.__f_->__clone(__f_);
1839        }
1840        else
1841        {
1842            __f_ = __f.__f_;
1843            __f.__f_ = nullptr;
1844        }
1845    }
1846
1847    _LIBCPP_INLINE_VISIBILITY
1848    ~__value_func()
1849    {
1850        if ((void*)__f_ == &__buf_)
1851            __f_->destroy();
1852        else if (__f_)
1853            __f_->destroy_deallocate();
1854    }
1855
1856    _LIBCPP_INLINE_VISIBILITY
1857    __value_func& operator=(__value_func&& __f)
1858    {
1859        *this = nullptr;
1860        if (__f.__f_ == nullptr)
1861            __f_ = nullptr;
1862        else if ((void*)__f.__f_ == &__f.__buf_)
1863        {
1864            __f_ = __as_base(&__buf_);
1865            __f.__f_->__clone(__f_);
1866        }
1867        else
1868        {
1869            __f_ = __f.__f_;
1870            __f.__f_ = nullptr;
1871        }
1872        return *this;
1873    }
1874
1875    _LIBCPP_INLINE_VISIBILITY
1876    __value_func& operator=(nullptr_t)
1877    {
1878        __func* __f = __f_;
1879        __f_ = nullptr;
1880        if ((void*)__f == &__buf_)
1881            __f->destroy();
1882        else if (__f)
1883            __f->destroy_deallocate();
1884        return *this;
1885    }
1886
1887    _LIBCPP_INLINE_VISIBILITY
1888    _Rp operator()(_ArgTypes&&... __args) const
1889    {
1890        if (__f_ == nullptr)
1891            __throw_bad_function_call();
1892        return (*__f_)(_VSTD::forward<_ArgTypes>(__args)...);
1893    }
1894
1895    _LIBCPP_INLINE_VISIBILITY
1896    void swap(__value_func& __f) _NOEXCEPT
1897    {
1898        if (&__f == this)
1899            return;
1900        if ((void*)__f_ == &__buf_ && (void*)__f.__f_ == &__f.__buf_)
1901        {
1902            typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
1903            __func* __t = __as_base(&__tempbuf);
1904            __f_->__clone(__t);
1905            __f_->destroy();
1906            __f_ = nullptr;
1907            __f.__f_->__clone(__as_base(&__buf_));
1908            __f.__f_->destroy();
1909            __f.__f_ = nullptr;
1910            __f_ = __as_base(&__buf_);
1911            __t->__clone(__as_base(&__f.__buf_));
1912            __t->destroy();
1913            __f.__f_ = __as_base(&__f.__buf_);
1914        }
1915        else if ((void*)__f_ == &__buf_)
1916        {
1917            __f_->__clone(__as_base(&__f.__buf_));
1918            __f_->destroy();
1919            __f_ = __f.__f_;
1920            __f.__f_ = __as_base(&__f.__buf_);
1921        }
1922        else if ((void*)__f.__f_ == &__f.__buf_)
1923        {
1924            __f.__f_->__clone(__as_base(&__buf_));
1925            __f.__f_->destroy();
1926            __f.__f_ = __f_;
1927            __f_ = __as_base(&__buf_);
1928        }
1929        else
1930            _VSTD::swap(__f_, __f.__f_);
1931    }
1932
1933    _LIBCPP_INLINE_VISIBILITY
1934    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT { return __f_ != nullptr; }
1935
1936#ifndef _LIBCPP_NO_RTTI
1937    _LIBCPP_INLINE_VISIBILITY
1938    const std::type_info& target_type() const _NOEXCEPT
1939    {
1940        if (__f_ == nullptr)
1941            return typeid(void);
1942        return __f_->target_type();
1943    }
1944
1945    template <typename _Tp>
1946    _LIBCPP_INLINE_VISIBILITY const _Tp* target() const _NOEXCEPT
1947    {
1948        if (__f_ == nullptr)
1949            return nullptr;
1950        return (const _Tp*)__f_->target(typeid(_Tp));
1951    }
1952#endif // _LIBCPP_NO_RTTI
1953};
1954
1955// Storage for a functor object, to be used with __policy to manage copy and
1956// destruction.
1957union __policy_storage
1958{
1959    mutable char __small[sizeof(void*) * 2];
1960    void* __large;
1961};
1962
1963// True if _Fun can safely be held in __policy_storage.__small.
1964template <typename _Fun>
1965struct __use_small_storage
1966    : public integral_constant<
1967          bool, sizeof(_Fun) <= sizeof(__policy_storage) &&
1968                    _LIBCPP_ALIGNOF(_Fun) <= _LIBCPP_ALIGNOF(__policy_storage) &&
1969                    is_trivially_copy_constructible<_Fun>::value &&
1970                    is_trivially_destructible<_Fun>::value> {};
1971
1972// Policy contains information about how to copy, destroy, and move the
1973// underlying functor. You can think of it as a vtable of sorts.
1974struct __policy
1975{
1976    // Used to copy or destroy __large values. null for trivial objects.
1977    void* (*const __clone)(const void*);
1978    void (*const __destroy)(void*);
1979
1980    // True if this is the null policy (no value).
1981    const bool __is_null;
1982
1983    // The target type. May be null if RTTI is disabled.
1984    const std::type_info* const __type_info;
1985
1986    // Returns a pointer to a static policy object suitable for the functor
1987    // type.
1988    template <typename _Fun>
1989    _LIBCPP_INLINE_VISIBILITY static const __policy* __create()
1990    {
1991        return __choose_policy<_Fun>(__use_small_storage<_Fun>());
1992    }
1993
1994    _LIBCPP_INLINE_VISIBILITY
1995    static const __policy* __create_empty()
1996    {
1997        static const _LIBCPP_CONSTEXPR __policy __policy_ = {nullptr, nullptr,
1998                                                             true,
1999#ifndef _LIBCPP_NO_RTTI
2000                                                             &typeid(void)
2001#else
2002                                                             nullptr
2003#endif
2004        };
2005        return &__policy_;
2006    }
2007
2008  private:
2009    template <typename _Fun> static void* __large_clone(const void* __s)
2010    {
2011        const _Fun* __f = static_cast<const _Fun*>(__s);
2012        return __f->__clone();
2013    }
2014
2015    template <typename _Fun>
2016    static void __large_destroy(void* __s) {
2017      _Fun::__destroy_and_delete(static_cast<_Fun*>(__s));
2018    }
2019
2020    template <typename _Fun>
2021    _LIBCPP_INLINE_VISIBILITY static const __policy*
2022    __choose_policy(/* is_small = */ false_type) {
2023      static const _LIBCPP_CONSTEXPR __policy __policy_ = {
2024          &__large_clone<_Fun>, &__large_destroy<_Fun>, false,
2025#ifndef _LIBCPP_NO_RTTI
2026          &typeid(typename _Fun::_Target)
2027#else
2028          nullptr
2029#endif
2030      };
2031        return &__policy_;
2032    }
2033
2034    template <typename _Fun>
2035    _LIBCPP_INLINE_VISIBILITY static const __policy*
2036        __choose_policy(/* is_small = */ true_type)
2037    {
2038        static const _LIBCPP_CONSTEXPR __policy __policy_ = {
2039            nullptr, nullptr, false,
2040#ifndef _LIBCPP_NO_RTTI
2041            &typeid(typename _Fun::_Target)
2042#else
2043            nullptr
2044#endif
2045        };
2046        return &__policy_;
2047    }
2048};
2049
2050// Used to choose between perfect forwarding or pass-by-value. Pass-by-value is
2051// faster for types that can be passed in registers.
2052template <typename _Tp>
2053using __fast_forward =
2054    typename conditional<is_scalar<_Tp>::value, _Tp, _Tp&&>::type;
2055
2056// __policy_invoker calls an instance of __alloc_func held in __policy_storage.
2057
2058template <class _Fp> struct __policy_invoker;
2059
2060template <class _Rp, class... _ArgTypes>
2061struct __policy_invoker<_Rp(_ArgTypes...)>
2062{
2063    typedef _Rp (*__Call)(const __policy_storage*,
2064                          __fast_forward<_ArgTypes>...);
2065
2066    __Call __call_;
2067
2068    // Creates an invoker that throws bad_function_call.
2069    _LIBCPP_INLINE_VISIBILITY
2070    __policy_invoker() : __call_(&__call_empty) {}
2071
2072    // Creates an invoker that calls the given instance of __func.
2073    template <typename _Fun>
2074    _LIBCPP_INLINE_VISIBILITY static __policy_invoker __create()
2075    {
2076        return __policy_invoker(&__call_impl<_Fun>);
2077    }
2078
2079  private:
2080    _LIBCPP_INLINE_VISIBILITY
2081    explicit __policy_invoker(__Call __c) : __call_(__c) {}
2082
2083    static _Rp __call_empty(const __policy_storage*,
2084                            __fast_forward<_ArgTypes>...)
2085    {
2086        __throw_bad_function_call();
2087    }
2088
2089    template <typename _Fun>
2090    static _Rp __call_impl(const __policy_storage* __buf,
2091                           __fast_forward<_ArgTypes>... __args)
2092    {
2093        _Fun* __f = reinterpret_cast<_Fun*>(__use_small_storage<_Fun>::value
2094                                                ? &__buf->__small
2095                                                : __buf->__large);
2096        return (*__f)(_VSTD::forward<_ArgTypes>(__args)...);
2097    }
2098};
2099
2100// __policy_func uses a __policy and __policy_invoker to create a type-erased,
2101// copyable functor.
2102
2103template <class _Fp> class __policy_func;
2104
2105template <class _Rp, class... _ArgTypes> class __policy_func<_Rp(_ArgTypes...)>
2106{
2107    // Inline storage for small objects.
2108    __policy_storage __buf_;
2109
2110    // Calls the value stored in __buf_. This could technically be part of
2111    // policy, but storing it here eliminates a level of indirection inside
2112    // operator().
2113    typedef __function::__policy_invoker<_Rp(_ArgTypes...)> __invoker;
2114    __invoker __invoker_;
2115
2116    // The policy that describes how to move / copy / destroy __buf_. Never
2117    // null, even if the function is empty.
2118    const __policy* __policy_;
2119
2120  public:
2121    _LIBCPP_INLINE_VISIBILITY
2122    __policy_func() : __policy_(__policy::__create_empty()) {}
2123
2124    template <class _Fp, class _Alloc>
2125    _LIBCPP_INLINE_VISIBILITY __policy_func(_Fp&& __f, const _Alloc& __a)
2126        : __policy_(__policy::__create_empty())
2127    {
2128        typedef __alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
2129        typedef allocator_traits<_Alloc> __alloc_traits;
2130        typedef typename __rebind_alloc_helper<__alloc_traits, _Fun>::type
2131            _FunAlloc;
2132
2133        if (__function::__not_null(__f))
2134        {
2135            __invoker_ = __invoker::template __create<_Fun>();
2136            __policy_ = __policy::__create<_Fun>();
2137
2138            _FunAlloc __af(__a);
2139            if (__use_small_storage<_Fun>())
2140            {
2141                ::new ((void*)&__buf_.__small)
2142                    _Fun(_VSTD::move(__f), _Alloc(__af));
2143            }
2144            else
2145            {
2146                typedef __allocator_destructor<_FunAlloc> _Dp;
2147                unique_ptr<_Fun, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
2148                ::new ((void*)__hold.get())
2149                    _Fun(_VSTD::move(__f), _Alloc(__af));
2150                __buf_.__large = __hold.release();
2151            }
2152        }
2153    }
2154
2155    template <class _Fp, class = typename enable_if<!is_same<typename decay<_Fp>::type, __policy_func>::value>::type>
2156    _LIBCPP_INLINE_VISIBILITY explicit __policy_func(_Fp&& __f)
2157        : __policy_(__policy::__create_empty()) {
2158      typedef __default_alloc_func<_Fp, _Rp(_ArgTypes...)> _Fun;
2159
2160      if (__function::__not_null(__f)) {
2161        __invoker_ = __invoker::template __create<_Fun>();
2162        __policy_ = __policy::__create<_Fun>();
2163        if (__use_small_storage<_Fun>()) {
2164          ::new ((void*)&__buf_.__small) _Fun(_VSTD::move(__f));
2165        } else {
2166          __builtin_new_allocator::__holder_t __hold =
2167              __builtin_new_allocator::__allocate_type<_Fun>(1);
2168          __buf_.__large = ::new ((void*)__hold.get()) _Fun(_VSTD::move(__f));
2169          (void)__hold.release();
2170        }
2171      }
2172    }
2173
2174    _LIBCPP_INLINE_VISIBILITY
2175    __policy_func(const __policy_func& __f)
2176        : __buf_(__f.__buf_), __invoker_(__f.__invoker_),
2177          __policy_(__f.__policy_)
2178    {
2179        if (__policy_->__clone)
2180            __buf_.__large = __policy_->__clone(__f.__buf_.__large);
2181    }
2182
2183    _LIBCPP_INLINE_VISIBILITY
2184    __policy_func(__policy_func&& __f)
2185        : __buf_(__f.__buf_), __invoker_(__f.__invoker_),
2186          __policy_(__f.__policy_)
2187    {
2188        if (__policy_->__destroy)
2189        {
2190            __f.__policy_ = __policy::__create_empty();
2191            __f.__invoker_ = __invoker();
2192        }
2193    }
2194
2195    _LIBCPP_INLINE_VISIBILITY
2196    ~__policy_func()
2197    {
2198        if (__policy_->__destroy)
2199            __policy_->__destroy(__buf_.__large);
2200    }
2201
2202    _LIBCPP_INLINE_VISIBILITY
2203    __policy_func& operator=(__policy_func&& __f)
2204    {
2205        *this = nullptr;
2206        __buf_ = __f.__buf_;
2207        __invoker_ = __f.__invoker_;
2208        __policy_ = __f.__policy_;
2209        __f.__policy_ = __policy::__create_empty();
2210        __f.__invoker_ = __invoker();
2211        return *this;
2212    }
2213
2214    _LIBCPP_INLINE_VISIBILITY
2215    __policy_func& operator=(nullptr_t)
2216    {
2217        const __policy* __p = __policy_;
2218        __policy_ = __policy::__create_empty();
2219        __invoker_ = __invoker();
2220        if (__p->__destroy)
2221            __p->__destroy(__buf_.__large);
2222        return *this;
2223    }
2224
2225    _LIBCPP_INLINE_VISIBILITY
2226    _Rp operator()(_ArgTypes&&... __args) const
2227    {
2228        return __invoker_.__call_(_VSTD::addressof(__buf_),
2229                                  _VSTD::forward<_ArgTypes>(__args)...);
2230    }
2231
2232    _LIBCPP_INLINE_VISIBILITY
2233    void swap(__policy_func& __f)
2234    {
2235        _VSTD::swap(__invoker_, __f.__invoker_);
2236        _VSTD::swap(__policy_, __f.__policy_);
2237        _VSTD::swap(__buf_, __f.__buf_);
2238    }
2239
2240    _LIBCPP_INLINE_VISIBILITY
2241    explicit operator bool() const _NOEXCEPT
2242    {
2243        return !__policy_->__is_null;
2244    }
2245
2246#ifndef _LIBCPP_NO_RTTI
2247    _LIBCPP_INLINE_VISIBILITY
2248    const std::type_info& target_type() const _NOEXCEPT
2249    {
2250        return *__policy_->__type_info;
2251    }
2252
2253    template <typename _Tp>
2254    _LIBCPP_INLINE_VISIBILITY const _Tp* target() const _NOEXCEPT
2255    {
2256        if (__policy_->__is_null || typeid(_Tp) != *__policy_->__type_info)
2257            return nullptr;
2258        if (__policy_->__clone) // Out of line storage.
2259            return reinterpret_cast<const _Tp*>(__buf_.__large);
2260        else
2261            return reinterpret_cast<const _Tp*>(&__buf_.__small);
2262    }
2263#endif // _LIBCPP_NO_RTTI
2264};
2265
2266#if defined(_LIBCPP_HAS_BLOCKS_RUNTIME) && !defined(_LIBCPP_HAS_OBJC_ARC)
2267
2268extern "C" void *_Block_copy(const void *);
2269extern "C" void _Block_release(const void *);
2270
2271template<class _Rp1, class ..._ArgTypes1, class _Alloc, class _Rp, class ..._ArgTypes>
2272class __func<_Rp1(^)(_ArgTypes1...), _Alloc, _Rp(_ArgTypes...)>
2273    : public  __base<_Rp(_ArgTypes...)>
2274{
2275    typedef _Rp1(^__block_type)(_ArgTypes1...);
2276    __block_type __f_;
2277
2278public:
2279    _LIBCPP_INLINE_VISIBILITY
2280    explicit __func(__block_type const& __f)
2281        : __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
2282    { }
2283
2284    // [TODO] add && to save on a retain
2285
2286    _LIBCPP_INLINE_VISIBILITY
2287    explicit __func(__block_type __f, const _Alloc& /* unused */)
2288        : __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
2289    { }
2290
2291    virtual __base<_Rp(_ArgTypes...)>* __clone() const {
2292        _LIBCPP_ASSERT(false,
2293            "Block pointers are just pointers, so they should always fit into "
2294            "std::function's small buffer optimization. This function should "
2295            "never be invoked.");
2296        return nullptr;
2297    }
2298
2299    virtual void __clone(__base<_Rp(_ArgTypes...)>* __p) const {
2300        ::new ((void*)__p) __func(__f_);
2301    }
2302
2303    virtual void destroy() _NOEXCEPT {
2304        if (__f_)
2305            _Block_release(__f_);
2306        __f_ = 0;
2307    }
2308
2309    virtual void destroy_deallocate() _NOEXCEPT {
2310        _LIBCPP_ASSERT(false,
2311            "Block pointers are just pointers, so they should always fit into "
2312            "std::function's small buffer optimization. This function should "
2313            "never be invoked.");
2314    }
2315
2316    virtual _Rp operator()(_ArgTypes&& ... __arg) {
2317        return _VSTD::__invoke(__f_, _VSTD::forward<_ArgTypes>(__arg)...);
2318    }
2319
2320#ifndef _LIBCPP_NO_RTTI
2321    virtual const void* target(type_info const& __ti) const _NOEXCEPT {
2322        if (__ti == typeid(__func::__block_type))
2323            return &__f_;
2324        return (const void*)nullptr;
2325    }
2326
2327    virtual const std::type_info& target_type() const _NOEXCEPT {
2328        return typeid(__func::__block_type);
2329    }
2330#endif // _LIBCPP_NO_RTTI
2331};
2332
2333#endif // _LIBCPP_HAS_EXTENSION_BLOCKS && !_LIBCPP_HAS_OBJC_ARC
2334
2335}  // __function
2336
2337template<class _Rp, class ..._ArgTypes>
2338class _LIBCPP_TEMPLATE_VIS function<_Rp(_ArgTypes...)>
2339    : public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
2340      public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
2341{
2342#ifndef _LIBCPP_ABI_OPTIMIZED_FUNCTION
2343    typedef __function::__value_func<_Rp(_ArgTypes...)> __func;
2344#else
2345    typedef __function::__policy_func<_Rp(_ArgTypes...)> __func;
2346#endif
2347
2348    __func __f_;
2349
2350    template <class _Fp, bool = _And<
2351        _IsNotSame<__uncvref_t<_Fp>, function>,
2352        __invokable<_Fp, _ArgTypes...>
2353    >::value>
2354    struct __callable;
2355    template <class _Fp>
2356        struct __callable<_Fp, true>
2357        {
2358            static const bool value = is_void<_Rp>::value ||
2359                __is_core_convertible<typename __invoke_of<_Fp, _ArgTypes...>::type,
2360                                      _Rp>::value;
2361        };
2362    template <class _Fp>
2363        struct __callable<_Fp, false>
2364        {
2365            static const bool value = false;
2366        };
2367
2368  template <class _Fp>
2369  using _EnableIfLValueCallable = typename enable_if<__callable<_Fp&>::value>::type;
2370public:
2371    typedef _Rp result_type;
2372
2373    // construct/copy/destroy:
2374    _LIBCPP_INLINE_VISIBILITY
2375    function() _NOEXCEPT { }
2376    _LIBCPP_INLINE_VISIBILITY
2377    function(nullptr_t) _NOEXCEPT {}
2378    function(const function&);
2379    function(function&&) _NOEXCEPT;
2380    template<class _Fp, class = _EnableIfLValueCallable<_Fp>>
2381    function(_Fp);
2382
2383#if _LIBCPP_STD_VER <= 14
2384    template<class _Alloc>
2385      _LIBCPP_INLINE_VISIBILITY
2386      function(allocator_arg_t, const _Alloc&) _NOEXCEPT {}
2387    template<class _Alloc>
2388      _LIBCPP_INLINE_VISIBILITY
2389      function(allocator_arg_t, const _Alloc&, nullptr_t) _NOEXCEPT {}
2390    template<class _Alloc>
2391      function(allocator_arg_t, const _Alloc&, const function&);
2392    template<class _Alloc>
2393      function(allocator_arg_t, const _Alloc&, function&&);
2394    template<class _Fp, class _Alloc, class = _EnableIfLValueCallable<_Fp>>
2395      function(allocator_arg_t, const _Alloc& __a, _Fp __f);
2396#endif
2397
2398    function& operator=(const function&);
2399    function& operator=(function&&) _NOEXCEPT;
2400    function& operator=(nullptr_t) _NOEXCEPT;
2401    template<class _Fp, class = _EnableIfLValueCallable<typename decay<_Fp>::type>>
2402    function& operator=(_Fp&&);
2403
2404    ~function();
2405
2406    // function modifiers:
2407    void swap(function&) _NOEXCEPT;
2408
2409#if _LIBCPP_STD_VER <= 14
2410    template<class _Fp, class _Alloc>
2411      _LIBCPP_INLINE_VISIBILITY
2412      void assign(_Fp&& __f, const _Alloc& __a)
2413        {function(allocator_arg, __a, _VSTD::forward<_Fp>(__f)).swap(*this);}
2414#endif
2415
2416    // function capacity:
2417    _LIBCPP_INLINE_VISIBILITY
2418    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {
2419      return static_cast<bool>(__f_);
2420    }
2421
2422    // deleted overloads close possible hole in the type system
2423    template<class _R2, class... _ArgTypes2>
2424      bool operator==(const function<_R2(_ArgTypes2...)>&) const = delete;
2425    template<class _R2, class... _ArgTypes2>
2426      bool operator!=(const function<_R2(_ArgTypes2...)>&) const = delete;
2427public:
2428    // function invocation:
2429    _Rp operator()(_ArgTypes...) const;
2430
2431#ifndef _LIBCPP_NO_RTTI
2432    // function target access:
2433    const std::type_info& target_type() const _NOEXCEPT;
2434    template <typename _Tp> _Tp* target() _NOEXCEPT;
2435    template <typename _Tp> const _Tp* target() const _NOEXCEPT;
2436#endif // _LIBCPP_NO_RTTI
2437};
2438
2439#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
2440template<class _Rp, class ..._Ap>
2441function(_Rp(*)(_Ap...)) -> function<_Rp(_Ap...)>;
2442
2443template<class _Fp>
2444struct __strip_signature;
2445
2446template<class _Rp, class _Gp, class ..._Ap>
2447struct __strip_signature<_Rp (_Gp::*) (_Ap...)> { using type = _Rp(_Ap...); };
2448template<class _Rp, class _Gp, class ..._Ap>
2449struct __strip_signature<_Rp (_Gp::*) (_Ap...) const> { using type = _Rp(_Ap...); };
2450template<class _Rp, class _Gp, class ..._Ap>
2451struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile> { using type = _Rp(_Ap...); };
2452template<class _Rp, class _Gp, class ..._Ap>
2453struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile> { using type = _Rp(_Ap...); };
2454
2455template<class _Rp, class _Gp, class ..._Ap>
2456struct __strip_signature<_Rp (_Gp::*) (_Ap...) &> { using type = _Rp(_Ap...); };
2457template<class _Rp, class _Gp, class ..._Ap>
2458struct __strip_signature<_Rp (_Gp::*) (_Ap...) const &> { using type = _Rp(_Ap...); };
2459template<class _Rp, class _Gp, class ..._Ap>
2460struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile &> { using type = _Rp(_Ap...); };
2461template<class _Rp, class _Gp, class ..._Ap>
2462struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile &> { using type = _Rp(_Ap...); };
2463
2464template<class _Rp, class _Gp, class ..._Ap>
2465struct __strip_signature<_Rp (_Gp::*) (_Ap...) noexcept> { using type = _Rp(_Ap...); };
2466template<class _Rp, class _Gp, class ..._Ap>
2467struct __strip_signature<_Rp (_Gp::*) (_Ap...) const noexcept> { using type = _Rp(_Ap...); };
2468template<class _Rp, class _Gp, class ..._Ap>
2469struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile noexcept> { using type = _Rp(_Ap...); };
2470template<class _Rp, class _Gp, class ..._Ap>
2471struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile noexcept> { using type = _Rp(_Ap...); };
2472
2473template<class _Rp, class _Gp, class ..._Ap>
2474struct __strip_signature<_Rp (_Gp::*) (_Ap...) & noexcept> { using type = _Rp(_Ap...); };
2475template<class _Rp, class _Gp, class ..._Ap>
2476struct __strip_signature<_Rp (_Gp::*) (_Ap...) const & noexcept> { using type = _Rp(_Ap...); };
2477template<class _Rp, class _Gp, class ..._Ap>
2478struct __strip_signature<_Rp (_Gp::*) (_Ap...) volatile & noexcept> { using type = _Rp(_Ap...); };
2479template<class _Rp, class _Gp, class ..._Ap>
2480struct __strip_signature<_Rp (_Gp::*) (_Ap...) const volatile & noexcept> { using type = _Rp(_Ap...); };
2481
2482template<class _Fp, class _Stripped = typename __strip_signature<decltype(&_Fp::operator())>::type>
2483function(_Fp) -> function<_Stripped>;
2484#endif // !_LIBCPP_HAS_NO_DEDUCTION_GUIDES
2485
2486template<class _Rp, class ..._ArgTypes>
2487function<_Rp(_ArgTypes...)>::function(const function& __f) : __f_(__f.__f_) {}
2488
2489#if _LIBCPP_STD_VER <= 14
2490template<class _Rp, class ..._ArgTypes>
2491template <class _Alloc>
2492function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
2493                                     const function& __f) : __f_(__f.__f_) {}
2494#endif
2495
2496template <class _Rp, class... _ArgTypes>
2497function<_Rp(_ArgTypes...)>::function(function&& __f) _NOEXCEPT
2498    : __f_(_VSTD::move(__f.__f_)) {}
2499
2500#if _LIBCPP_STD_VER <= 14
2501template<class _Rp, class ..._ArgTypes>
2502template <class _Alloc>
2503function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
2504                                      function&& __f)
2505    : __f_(_VSTD::move(__f.__f_)) {}
2506#endif
2507
2508template <class _Rp, class... _ArgTypes>
2509template <class _Fp, class>
2510function<_Rp(_ArgTypes...)>::function(_Fp __f) : __f_(_VSTD::move(__f)) {}
2511
2512#if _LIBCPP_STD_VER <= 14
2513template <class _Rp, class... _ArgTypes>
2514template <class _Fp, class _Alloc, class>
2515function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc& __a,
2516                                      _Fp __f)
2517    : __f_(_VSTD::move(__f), __a) {}
2518#endif
2519
2520template<class _Rp, class ..._ArgTypes>
2521function<_Rp(_ArgTypes...)>&
2522function<_Rp(_ArgTypes...)>::operator=(const function& __f)
2523{
2524    function(__f).swap(*this);
2525    return *this;
2526}
2527
2528template<class _Rp, class ..._ArgTypes>
2529function<_Rp(_ArgTypes...)>&
2530function<_Rp(_ArgTypes...)>::operator=(function&& __f) _NOEXCEPT
2531{
2532    __f_ = _VSTD::move(__f.__f_);
2533    return *this;
2534}
2535
2536template<class _Rp, class ..._ArgTypes>
2537function<_Rp(_ArgTypes...)>&
2538function<_Rp(_ArgTypes...)>::operator=(nullptr_t) _NOEXCEPT
2539{
2540    __f_ = nullptr;
2541    return *this;
2542}
2543
2544template<class _Rp, class ..._ArgTypes>
2545template <class _Fp, class>
2546function<_Rp(_ArgTypes...)>&
2547function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f)
2548{
2549    function(_VSTD::forward<_Fp>(__f)).swap(*this);
2550    return *this;
2551}
2552
2553template<class _Rp, class ..._ArgTypes>
2554function<_Rp(_ArgTypes...)>::~function() {}
2555
2556template<class _Rp, class ..._ArgTypes>
2557void
2558function<_Rp(_ArgTypes...)>::swap(function& __f) _NOEXCEPT
2559{
2560    __f_.swap(__f.__f_);
2561}
2562
2563template<class _Rp, class ..._ArgTypes>
2564_Rp
2565function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
2566{
2567    return __f_(_VSTD::forward<_ArgTypes>(__arg)...);
2568}
2569
2570#ifndef _LIBCPP_NO_RTTI
2571
2572template<class _Rp, class ..._ArgTypes>
2573const std::type_info&
2574function<_Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
2575{
2576    return __f_.target_type();
2577}
2578
2579template<class _Rp, class ..._ArgTypes>
2580template <typename _Tp>
2581_Tp*
2582function<_Rp(_ArgTypes...)>::target() _NOEXCEPT
2583{
2584    return (_Tp*)(__f_.template target<_Tp>());
2585}
2586
2587template<class _Rp, class ..._ArgTypes>
2588template <typename _Tp>
2589const _Tp*
2590function<_Rp(_ArgTypes...)>::target() const _NOEXCEPT
2591{
2592    return __f_.template target<_Tp>();
2593}
2594
2595#endif // _LIBCPP_NO_RTTI
2596
2597template <class _Rp, class... _ArgTypes>
2598inline _LIBCPP_INLINE_VISIBILITY
2599bool
2600operator==(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return !__f;}
2601
2602template <class _Rp, class... _ArgTypes>
2603inline _LIBCPP_INLINE_VISIBILITY
2604bool
2605operator==(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return !__f;}
2606
2607template <class _Rp, class... _ArgTypes>
2608inline _LIBCPP_INLINE_VISIBILITY
2609bool
2610operator!=(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return (bool)__f;}
2611
2612template <class _Rp, class... _ArgTypes>
2613inline _LIBCPP_INLINE_VISIBILITY
2614bool
2615operator!=(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return (bool)__f;}
2616
2617template <class _Rp, class... _ArgTypes>
2618inline _LIBCPP_INLINE_VISIBILITY
2619void
2620swap(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y) _NOEXCEPT
2621{return __x.swap(__y);}
2622
2623#else // _LIBCPP_CXX03_LANG
2624
2625#include <__functional_03>
2626
2627#endif
2628
2629////////////////////////////////////////////////////////////////////////////////
2630//                                  BIND
2631//==============================================================================
2632
2633template<class _Tp> struct __is_bind_expression : public false_type {};
2634template<class _Tp> struct _LIBCPP_TEMPLATE_VIS is_bind_expression
2635    : public __is_bind_expression<typename remove_cv<_Tp>::type> {};
2636
2637#if _LIBCPP_STD_VER > 14
2638template <class _Tp>
2639_LIBCPP_INLINE_VAR constexpr size_t is_bind_expression_v = is_bind_expression<_Tp>::value;
2640#endif
2641
2642template<class _Tp> struct __is_placeholder : public integral_constant<int, 0> {};
2643template<class _Tp> struct _LIBCPP_TEMPLATE_VIS is_placeholder
2644    : public __is_placeholder<typename remove_cv<_Tp>::type> {};
2645
2646#if _LIBCPP_STD_VER > 14
2647template <class _Tp>
2648_LIBCPP_INLINE_VAR constexpr size_t is_placeholder_v = is_placeholder<_Tp>::value;
2649#endif
2650
2651namespace placeholders
2652{
2653
2654template <int _Np> struct __ph {};
2655
2656#if defined(_LIBCPP_CXX03_LANG) || defined(_LIBCPP_BUILDING_LIBRARY)
2657_LIBCPP_FUNC_VIS extern const __ph<1>   _1;
2658_LIBCPP_FUNC_VIS extern const __ph<2>   _2;
2659_LIBCPP_FUNC_VIS extern const __ph<3>   _3;
2660_LIBCPP_FUNC_VIS extern const __ph<4>   _4;
2661_LIBCPP_FUNC_VIS extern const __ph<5>   _5;
2662_LIBCPP_FUNC_VIS extern const __ph<6>   _6;
2663_LIBCPP_FUNC_VIS extern const __ph<7>   _7;
2664_LIBCPP_FUNC_VIS extern const __ph<8>   _8;
2665_LIBCPP_FUNC_VIS extern const __ph<9>   _9;
2666_LIBCPP_FUNC_VIS extern const __ph<10> _10;
2667#else
2668/* _LIBCPP_INLINE_VAR */ constexpr __ph<1>   _1{};
2669/* _LIBCPP_INLINE_VAR */ constexpr __ph<2>   _2{};
2670/* _LIBCPP_INLINE_VAR */ constexpr __ph<3>   _3{};
2671/* _LIBCPP_INLINE_VAR */ constexpr __ph<4>   _4{};
2672/* _LIBCPP_INLINE_VAR */ constexpr __ph<5>   _5{};
2673/* _LIBCPP_INLINE_VAR */ constexpr __ph<6>   _6{};
2674/* _LIBCPP_INLINE_VAR */ constexpr __ph<7>   _7{};
2675/* _LIBCPP_INLINE_VAR */ constexpr __ph<8>   _8{};
2676/* _LIBCPP_INLINE_VAR */ constexpr __ph<9>   _9{};
2677/* _LIBCPP_INLINE_VAR */ constexpr __ph<10> _10{};
2678#endif // defined(_LIBCPP_CXX03_LANG) || defined(_LIBCPP_BUILDING_LIBRARY)
2679
2680}  // placeholders
2681
2682template<int _Np>
2683struct __is_placeholder<placeholders::__ph<_Np> >
2684    : public integral_constant<int, _Np> {};
2685
2686
2687#ifndef _LIBCPP_CXX03_LANG
2688
2689template <class _Tp, class _Uj>
2690inline _LIBCPP_INLINE_VISIBILITY
2691_Tp&
2692__mu(reference_wrapper<_Tp> __t, _Uj&)
2693{
2694    return __t.get();
2695}
2696
2697template <class _Ti, class ..._Uj, size_t ..._Indx>
2698inline _LIBCPP_INLINE_VISIBILITY
2699typename __invoke_of<_Ti&, _Uj...>::type
2700__mu_expand(_Ti& __ti, tuple<_Uj...>& __uj, __tuple_indices<_Indx...>)
2701{
2702    return __ti(_VSTD::forward<_Uj>(_VSTD::get<_Indx>(__uj))...);
2703}
2704
2705template <class _Ti, class ..._Uj>
2706inline _LIBCPP_INLINE_VISIBILITY
2707typename _EnableIf
2708<
2709    is_bind_expression<_Ti>::value,
2710    __invoke_of<_Ti&, _Uj...>
2711>::type
2712__mu(_Ti& __ti, tuple<_Uj...>& __uj)
2713{
2714    typedef typename __make_tuple_indices<sizeof...(_Uj)>::type __indices;
2715    return _VSTD::__mu_expand(__ti, __uj, __indices());
2716}
2717
2718template <bool IsPh, class _Ti, class _Uj>
2719struct __mu_return2 {};
2720
2721template <class _Ti, class _Uj>
2722struct __mu_return2<true, _Ti, _Uj>
2723{
2724    typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _Uj>::type type;
2725};
2726
2727template <class _Ti, class _Uj>
2728inline _LIBCPP_INLINE_VISIBILITY
2729typename enable_if
2730<
2731    0 < is_placeholder<_Ti>::value,
2732    typename __mu_return2<0 < is_placeholder<_Ti>::value, _Ti, _Uj>::type
2733>::type
2734__mu(_Ti&, _Uj& __uj)
2735{
2736    const size_t _Indx = is_placeholder<_Ti>::value - 1;
2737    return _VSTD::forward<typename tuple_element<_Indx, _Uj>::type>(_VSTD::get<_Indx>(__uj));
2738}
2739
2740template <class _Ti, class _Uj>
2741inline _LIBCPP_INLINE_VISIBILITY
2742typename enable_if
2743<
2744    !is_bind_expression<_Ti>::value &&
2745    is_placeholder<_Ti>::value == 0 &&
2746    !__is_reference_wrapper<_Ti>::value,
2747    _Ti&
2748>::type
2749__mu(_Ti& __ti, _Uj&)
2750{
2751    return __ti;
2752}
2753
2754template <class _Ti, bool IsReferenceWrapper, bool IsBindEx, bool IsPh,
2755          class _TupleUj>
2756struct __mu_return_impl;
2757
2758template <bool _Invokable, class _Ti, class ..._Uj>
2759struct __mu_return_invokable  // false
2760{
2761    typedef __nat type;
2762};
2763
2764template <class _Ti, class ..._Uj>
2765struct __mu_return_invokable<true, _Ti, _Uj...>
2766{
2767    typedef typename __invoke_of<_Ti&, _Uj...>::type type;
2768};
2769
2770template <class _Ti, class ..._Uj>
2771struct __mu_return_impl<_Ti, false, true, false, tuple<_Uj...> >
2772    : public __mu_return_invokable<__invokable<_Ti&, _Uj...>::value, _Ti, _Uj...>
2773{
2774};
2775
2776template <class _Ti, class _TupleUj>
2777struct __mu_return_impl<_Ti, false, false, true, _TupleUj>
2778{
2779    typedef typename tuple_element<is_placeholder<_Ti>::value - 1,
2780                                   _TupleUj>::type&& type;
2781};
2782
2783template <class _Ti, class _TupleUj>
2784struct __mu_return_impl<_Ti, true, false, false, _TupleUj>
2785{
2786    typedef typename _Ti::type& type;
2787};
2788
2789template <class _Ti, class _TupleUj>
2790struct __mu_return_impl<_Ti, false, false, false, _TupleUj>
2791{
2792    typedef _Ti& type;
2793};
2794
2795template <class _Ti, class _TupleUj>
2796struct __mu_return
2797    : public __mu_return_impl<_Ti,
2798                              __is_reference_wrapper<_Ti>::value,
2799                              is_bind_expression<_Ti>::value,
2800                              0 < is_placeholder<_Ti>::value &&
2801                              is_placeholder<_Ti>::value <= tuple_size<_TupleUj>::value,
2802                              _TupleUj>
2803{
2804};
2805
2806template <class _Fp, class _BoundArgs, class _TupleUj>
2807struct __is_valid_bind_return
2808{
2809    static const bool value = false;
2810};
2811
2812template <class _Fp, class ..._BoundArgs, class _TupleUj>
2813struct __is_valid_bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj>
2814{
2815    static const bool value = __invokable<_Fp,
2816                    typename __mu_return<_BoundArgs, _TupleUj>::type...>::value;
2817};
2818
2819template <class _Fp, class ..._BoundArgs, class _TupleUj>
2820struct __is_valid_bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj>
2821{
2822    static const bool value = __invokable<_Fp,
2823                    typename __mu_return<const _BoundArgs, _TupleUj>::type...>::value;
2824};
2825
2826template <class _Fp, class _BoundArgs, class _TupleUj,
2827          bool = __is_valid_bind_return<_Fp, _BoundArgs, _TupleUj>::value>
2828struct __bind_return;
2829
2830template <class _Fp, class ..._BoundArgs, class _TupleUj>
2831struct __bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj, true>
2832{
2833    typedef typename __invoke_of
2834    <
2835        _Fp&,
2836        typename __mu_return
2837        <
2838            _BoundArgs,
2839            _TupleUj
2840        >::type...
2841    >::type type;
2842};
2843
2844template <class _Fp, class ..._BoundArgs, class _TupleUj>
2845struct __bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj, true>
2846{
2847    typedef typename __invoke_of
2848    <
2849        _Fp&,
2850        typename __mu_return
2851        <
2852            const _BoundArgs,
2853            _TupleUj
2854        >::type...
2855    >::type type;
2856};
2857
2858template <class _Fp, class _BoundArgs, size_t ..._Indx, class _Args>
2859inline _LIBCPP_INLINE_VISIBILITY
2860typename __bind_return<_Fp, _BoundArgs, _Args>::type
2861__apply_functor(_Fp& __f, _BoundArgs& __bound_args, __tuple_indices<_Indx...>,
2862                _Args&& __args)
2863{
2864    return _VSTD::__invoke(__f, _VSTD::__mu(_VSTD::get<_Indx>(__bound_args), __args)...);
2865}
2866
2867template<class _Fp, class ..._BoundArgs>
2868class __bind
2869    : public __weak_result_type<typename decay<_Fp>::type>
2870{
2871protected:
2872    typedef typename decay<_Fp>::type _Fd;
2873    typedef tuple<typename decay<_BoundArgs>::type...> _Td;
2874private:
2875    _Fd __f_;
2876    _Td __bound_args_;
2877
2878    typedef typename __make_tuple_indices<sizeof...(_BoundArgs)>::type __indices;
2879public:
2880    template <class _Gp, class ..._BA,
2881              class = typename enable_if
2882                               <
2883                                  is_constructible<_Fd, _Gp>::value &&
2884                                  !is_same<typename remove_reference<_Gp>::type,
2885                                           __bind>::value
2886                               >::type>
2887      _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2888      explicit __bind(_Gp&& __f, _BA&& ...__bound_args)
2889        : __f_(_VSTD::forward<_Gp>(__f)),
2890          __bound_args_(_VSTD::forward<_BA>(__bound_args)...) {}
2891
2892    template <class ..._Args>
2893        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2894        typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
2895        operator()(_Args&& ...__args)
2896        {
2897            return _VSTD::__apply_functor(__f_, __bound_args_, __indices(),
2898                                  tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
2899        }
2900
2901    template <class ..._Args>
2902        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2903        typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type
2904        operator()(_Args&& ...__args) const
2905        {
2906            return _VSTD::__apply_functor(__f_, __bound_args_, __indices(),
2907                                   tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
2908        }
2909};
2910
2911template<class _Fp, class ..._BoundArgs>
2912struct __is_bind_expression<__bind<_Fp, _BoundArgs...> > : public true_type {};
2913
2914template<class _Rp, class _Fp, class ..._BoundArgs>
2915class __bind_r
2916    : public __bind<_Fp, _BoundArgs...>
2917{
2918    typedef __bind<_Fp, _BoundArgs...> base;
2919    typedef typename base::_Fd _Fd;
2920    typedef typename base::_Td _Td;
2921public:
2922    typedef _Rp result_type;
2923
2924
2925    template <class _Gp, class ..._BA,
2926              class = typename enable_if
2927                               <
2928                                  is_constructible<_Fd, _Gp>::value &&
2929                                  !is_same<typename remove_reference<_Gp>::type,
2930                                           __bind_r>::value
2931                               >::type>
2932      _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2933      explicit __bind_r(_Gp&& __f, _BA&& ...__bound_args)
2934        : base(_VSTD::forward<_Gp>(__f),
2935               _VSTD::forward<_BA>(__bound_args)...) {}
2936
2937    template <class ..._Args>
2938        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2939        typename enable_if
2940        <
2941            is_convertible<typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type,
2942                           result_type>::value || is_void<_Rp>::value,
2943            result_type
2944        >::type
2945        operator()(_Args&& ...__args)
2946        {
2947            typedef __invoke_void_return_wrapper<_Rp> _Invoker;
2948            return _Invoker::__call(static_cast<base&>(*this), _VSTD::forward<_Args>(__args)...);
2949        }
2950
2951    template <class ..._Args>
2952        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2953        typename enable_if
2954        <
2955            is_convertible<typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type,
2956                           result_type>::value || is_void<_Rp>::value,
2957            result_type
2958        >::type
2959        operator()(_Args&& ...__args) const
2960        {
2961            typedef __invoke_void_return_wrapper<_Rp> _Invoker;
2962            return _Invoker::__call(static_cast<base const&>(*this), _VSTD::forward<_Args>(__args)...);
2963        }
2964};
2965
2966template<class _Rp, class _Fp, class ..._BoundArgs>
2967struct __is_bind_expression<__bind_r<_Rp, _Fp, _BoundArgs...> > : public true_type {};
2968
2969template<class _Fp, class ..._BoundArgs>
2970inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2971__bind<_Fp, _BoundArgs...>
2972bind(_Fp&& __f, _BoundArgs&&... __bound_args)
2973{
2974    typedef __bind<_Fp, _BoundArgs...> type;
2975    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
2976}
2977
2978template<class _Rp, class _Fp, class ..._BoundArgs>
2979inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2980__bind_r<_Rp, _Fp, _BoundArgs...>
2981bind(_Fp&& __f, _BoundArgs&&... __bound_args)
2982{
2983    typedef __bind_r<_Rp, _Fp, _BoundArgs...> type;
2984    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
2985}
2986
2987#endif // _LIBCPP_CXX03_LANG
2988
2989#if _LIBCPP_STD_VER > 14
2990
2991template<class _Op, class _Tuple,
2992         class _Idxs = typename __make_tuple_indices<tuple_size<_Tuple>::value>::type>
2993struct __perfect_forward_impl;
2994
2995template<class _Op, class... _Bound, size_t... _Idxs>
2996struct __perfect_forward_impl<_Op, __tuple_types<_Bound...>, __tuple_indices<_Idxs...>>
2997{
2998    tuple<_Bound...> __bound_;
2999
3000    template<class... _Args>
3001    _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) &
3002    noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...)))
3003    -> decltype(      _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...))
3004    {return           _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...);}
3005
3006    template<class... _Args>
3007    _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) const&
3008    noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...)))
3009    -> decltype(      _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...))
3010    {return           _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...);}
3011
3012    template<class... _Args>
3013    _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) &&
3014    noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3015                                  _VSTD::forward<_Args>(__args)...)))
3016    -> decltype(      _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3017                                  _VSTD::forward<_Args>(__args)...))
3018    {return           _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3019                                  _VSTD::forward<_Args>(__args)...);}
3020
3021    template<class... _Args>
3022    _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) const&&
3023    noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3024                                  _VSTD::forward<_Args>(__args)...)))
3025    -> decltype(      _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3026                                  _VSTD::forward<_Args>(__args)...))
3027    {return           _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))...,
3028                                  _VSTD::forward<_Args>(__args)...);}
3029
3030    template<class _Fn = typename tuple_element<0, tuple<_Bound...>>::type,
3031             class = _EnableIf<is_copy_constructible_v<_Fn>>>
3032    constexpr __perfect_forward_impl(__perfect_forward_impl const& __other)
3033        : __bound_(__other.__bound_) {}
3034
3035    template<class _Fn = typename tuple_element<0, tuple<_Bound...>>::type,
3036             class = _EnableIf<is_move_constructible_v<_Fn>>>
3037    constexpr __perfect_forward_impl(__perfect_forward_impl && __other)
3038        : __bound_(_VSTD::move(__other.__bound_)) {}
3039
3040    template<class... _BoundArgs>
3041    explicit constexpr __perfect_forward_impl(_BoundArgs&&... __bound) :
3042        __bound_(_VSTD::forward<_BoundArgs>(__bound)...) { }
3043};
3044
3045template<class _Op, class... _Args>
3046using __perfect_forward =
3047    __perfect_forward_impl<_Op, __tuple_types<decay_t<_Args>...>>;
3048
3049struct __not_fn_op
3050{
3051    template<class... _Args>
3052    static _LIBCPP_CONSTEXPR_AFTER_CXX17 auto __call(_Args&&... __args)
3053    noexcept(noexcept(!_VSTD::invoke(_VSTD::forward<_Args>(__args)...)))
3054    -> decltype(      !_VSTD::invoke(_VSTD::forward<_Args>(__args)...))
3055    { return          !_VSTD::invoke(_VSTD::forward<_Args>(__args)...); }
3056};
3057
3058template<class _Fn,
3059         class = _EnableIf<is_constructible_v<decay_t<_Fn>, _Fn> &&
3060                           is_move_constructible_v<_Fn>>>
3061_LIBCPP_CONSTEXPR_AFTER_CXX17 auto not_fn(_Fn&& __f)
3062{
3063    return __perfect_forward<__not_fn_op, _Fn>(_VSTD::forward<_Fn>(__f));
3064}
3065
3066#endif // _LIBCPP_STD_VER > 14
3067
3068#if _LIBCPP_STD_VER > 17
3069
3070struct __bind_front_op
3071{
3072    template<class... _Args>
3073    constexpr static auto __call(_Args&&... __args)
3074    noexcept(noexcept(_VSTD::invoke(_VSTD::forward<_Args>(__args)...)))
3075    -> decltype(      _VSTD::invoke(_VSTD::forward<_Args>(__args)...))
3076    { return          _VSTD::invoke(_VSTD::forward<_Args>(__args)...); }
3077};
3078
3079template<class _Fn, class... _Args,
3080         class = _EnableIf<conjunction<is_constructible<decay_t<_Fn>, _Fn>,
3081                                       is_move_constructible<decay_t<_Fn>>,
3082                                       is_constructible<decay_t<_Args>, _Args>...,
3083                                       is_move_constructible<decay_t<_Args>>...
3084                                       >::value>>
3085constexpr auto bind_front(_Fn&& __f, _Args&&... __args)
3086{
3087    return __perfect_forward<__bind_front_op, _Fn, _Args...>(_VSTD::forward<_Fn>(__f),
3088                                                             _VSTD::forward<_Args>(__args)...);
3089}
3090
3091#endif // _LIBCPP_STD_VER > 17
3092
3093// struct hash<T*> in <memory>
3094
3095template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
3096pair<_ForwardIterator1, _ForwardIterator1> _LIBCPP_CONSTEXPR_AFTER_CXX11
3097__search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3098         _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
3099         forward_iterator_tag, forward_iterator_tag)
3100{
3101    if (__first2 == __last2)
3102        return _VSTD::make_pair(__first1, __first1);  // Everything matches an empty sequence
3103    while (true)
3104    {
3105        // Find first element in sequence 1 that matchs *__first2, with a mininum of loop checks
3106        while (true)
3107        {
3108            if (__first1 == __last1)  // return __last1 if no element matches *__first2
3109                return _VSTD::make_pair(__last1, __last1);
3110            if (__pred(*__first1, *__first2))
3111                break;
3112            ++__first1;
3113        }
3114        // *__first1 matches *__first2, now match elements after here
3115        _ForwardIterator1 __m1 = __first1;
3116        _ForwardIterator2 __m2 = __first2;
3117        while (true)
3118        {
3119            if (++__m2 == __last2)  // If pattern exhausted, __first1 is the answer (works for 1 element pattern)
3120                return _VSTD::make_pair(__first1, __m1);
3121            if (++__m1 == __last1)  // Otherwise if source exhaused, pattern not found
3122                return _VSTD::make_pair(__last1, __last1);
3123            if (!__pred(*__m1, *__m2))  // if there is a mismatch, restart with a new __first1
3124            {
3125                ++__first1;
3126                break;
3127            }  // else there is a match, check next elements
3128        }
3129    }
3130}
3131
3132template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
3133_LIBCPP_CONSTEXPR_AFTER_CXX11
3134pair<_RandomAccessIterator1, _RandomAccessIterator1>
3135__search(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
3136         _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
3137           random_access_iterator_tag, random_access_iterator_tag)
3138{
3139    typedef typename iterator_traits<_RandomAccessIterator1>::difference_type _D1;
3140    typedef typename iterator_traits<_RandomAccessIterator2>::difference_type _D2;
3141    // Take advantage of knowing source and pattern lengths.  Stop short when source is smaller than pattern
3142    const _D2 __len2 = __last2 - __first2;
3143    if (__len2 == 0)
3144        return _VSTD::make_pair(__first1, __first1);
3145    const _D1 __len1 = __last1 - __first1;
3146    if (__len1 < __len2)
3147        return _VSTD::make_pair(__last1, __last1);
3148    const _RandomAccessIterator1 __s = __last1 - (__len2 - 1);  // Start of pattern match can't go beyond here
3149
3150    while (true)
3151    {
3152        while (true)
3153        {
3154            if (__first1 == __s)
3155                return _VSTD::make_pair(__last1, __last1);
3156            if (__pred(*__first1, *__first2))
3157                break;
3158            ++__first1;
3159        }
3160
3161        _RandomAccessIterator1 __m1 = __first1;
3162        _RandomAccessIterator2 __m2 = __first2;
3163         while (true)
3164         {
3165             if (++__m2 == __last2)
3166                 return _VSTD::make_pair(__first1, __first1 + __len2);
3167             ++__m1;          // no need to check range on __m1 because __s guarantees we have enough source
3168             if (!__pred(*__m1, *__m2))
3169             {
3170                 ++__first1;
3171                 break;
3172             }
3173         }
3174    }
3175}
3176
3177#if _LIBCPP_STD_VER > 14
3178
3179// default searcher
3180template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
3181class _LIBCPP_TEMPLATE_VIS default_searcher {
3182public:
3183    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3184    default_searcher(_ForwardIterator __f, _ForwardIterator __l,
3185                       _BinaryPredicate __p = _BinaryPredicate())
3186        : __first_(__f), __last_(__l), __pred_(__p) {}
3187
3188    template <typename _ForwardIterator2>
3189    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
3190    pair<_ForwardIterator2, _ForwardIterator2>
3191    operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const
3192    {
3193        return _VSTD::__search(__f, __l, __first_, __last_, __pred_,
3194            typename iterator_traits<_ForwardIterator>::iterator_category(),
3195            typename iterator_traits<_ForwardIterator2>::iterator_category());
3196    }
3197
3198private:
3199    _ForwardIterator __first_;
3200    _ForwardIterator __last_;
3201    _BinaryPredicate __pred_;
3202    };
3203
3204#endif // _LIBCPP_STD_VER > 14
3205
3206#if _LIBCPP_STD_VER > 17
3207template <class _Tp>
3208using unwrap_reference_t = typename unwrap_reference<_Tp>::type;
3209
3210template <class _Tp>
3211using unwrap_ref_decay_t = typename unwrap_ref_decay<_Tp>::type;
3212#endif // > C++17
3213
3214#if _LIBCPP_STD_VER > 17
3215// [func.identity]
3216struct identity {
3217    template<class _Tp>
3218    _LIBCPP_NODISCARD_EXT constexpr _Tp&& operator()(_Tp&& __t) const noexcept
3219    {
3220        return _VSTD::forward<_Tp>(__t);
3221    }
3222
3223    using is_transparent = void;
3224};
3225#endif // _LIBCPP_STD_VER > 17
3226
3227#if !defined(_LIBCPP_HAS_NO_RANGES)
3228
3229namespace ranges {
3230
3231struct equal_to {
3232  template <class _Tp, class _Up>
3233  requires equality_comparable_with<_Tp, _Up>
3234  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3235      noexcept(noexcept(bool(_VSTD::forward<_Tp>(__t) == _VSTD::forward<_Up>(__u)))) {
3236    return _VSTD::forward<_Tp>(__t) == _VSTD::forward<_Up>(__u);
3237  }
3238
3239  using is_transparent = void;
3240};
3241
3242struct not_equal_to {
3243  template <class _Tp, class _Up>
3244  requires equality_comparable_with<_Tp, _Up>
3245  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3246      noexcept(noexcept(bool(!(_VSTD::forward<_Tp>(__t) == _VSTD::forward<_Up>(__u))))) {
3247    return !(_VSTD::forward<_Tp>(__t) == _VSTD::forward<_Up>(__u));
3248  }
3249
3250  using is_transparent = void;
3251};
3252
3253struct greater {
3254  template <class _Tp, class _Up>
3255  requires totally_ordered_with<_Tp, _Up>
3256  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3257      noexcept(noexcept(bool(_VSTD::forward<_Up>(__u) < _VSTD::forward<_Tp>(__t)))) {
3258    return _VSTD::forward<_Up>(__u) < _VSTD::forward<_Tp>(__t);
3259  }
3260
3261  using is_transparent = void;
3262};
3263
3264struct less {
3265  template <class _Tp, class _Up>
3266  requires totally_ordered_with<_Tp, _Up>
3267  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3268      noexcept(noexcept(bool(_VSTD::forward<_Tp>(__t) < _VSTD::forward<_Up>(__u)))) {
3269    return _VSTD::forward<_Tp>(__t) < _VSTD::forward<_Up>(__u);
3270  }
3271
3272  using is_transparent = void;
3273};
3274
3275struct greater_equal {
3276  template <class _Tp, class _Up>
3277  requires totally_ordered_with<_Tp, _Up>
3278  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3279      noexcept(noexcept(bool(!(_VSTD::forward<_Tp>(__t) < _VSTD::forward<_Up>(__u))))) {
3280    return !(_VSTD::forward<_Tp>(__t) < _VSTD::forward<_Up>(__u));
3281  }
3282
3283  using is_transparent = void;
3284};
3285
3286struct less_equal {
3287  template <class _Tp, class _Up>
3288  requires totally_ordered_with<_Tp, _Up>
3289  [[nodiscard]] constexpr bool operator()(_Tp &&__t, _Up &&__u) const
3290      noexcept(noexcept(bool(!(_VSTD::forward<_Up>(__u) < _VSTD::forward<_Tp>(__t))))) {
3291    return !(_VSTD::forward<_Up>(__u) < _VSTD::forward<_Tp>(__t));
3292  }
3293
3294  using is_transparent = void;
3295};
3296
3297} // namespace ranges
3298
3299#endif // !defined(_LIBCPP_HAS_NO_RANGES)
3300
3301_LIBCPP_END_NAMESPACE_STD
3302
3303#endif // _LIBCPP_FUNCTIONAL
3304