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