functional revision 232924 
1// -*- C++ -*-
2//===------------------------ functional ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_FUNCTIONAL
12#define _LIBCPP_FUNCTIONAL
13
14/*
15    functional synopsis
16
17namespace std
18{
19
20template <class Arg, class Result>
21struct unary_function
22{
23    typedef Arg    argument_type;
24    typedef Result result_type;
25};
26
27template <class Arg1, class Arg2, class Result>
28struct binary_function
29{
30    typedef Arg1   first_argument_type;
31    typedef Arg2   second_argument_type;
32    typedef Result result_type;
33};
34
35template <class T>
36class reference_wrapper
37    : public unary_function<T1, R> // if wrapping a unary functor
38    : public binary_function<T1, T2, R> // if wraping a binary functor
39{
40public:
41    // types
42    typedef T type;
43    typedef see below result_type; // Not always defined
44
45    // construct/copy/destroy
46    reference_wrapper(T&) noexcept;
47    reference_wrapper(T&&) = delete; // do not bind to temps
48    reference_wrapper(const reference_wrapper<T>& x) noexcept;
49
50    // assignment
51    reference_wrapper& operator=(const reference_wrapper<T>& x) noexcept;
52
53    // access
54    operator T& () const noexcept;
55    T& get() const noexcept;
56
57    // invoke
58    template <class... ArgTypes>
59      typename result_of<T(ArgTypes...)>::type
60          operator() (ArgTypes&&...) const;
61};
62
63template <class T> reference_wrapper<T> ref(T& t) noexcept;
64template <class T> void ref(const T&& t) = delete;
65template <class T> reference_wrapper<T> ref(reference_wrapper<T>t) noexcept;
66
67template <class T> reference_wrapper<const T> cref(const T& t) noexcept;
68template <class T> void cref(const T&& t) = delete;
69template <class T> reference_wrapper<const T> cref(reference_wrapper<T> t) noexcept;
70
71template <class T>
72struct plus : binary_function<T, T, T>
73{
74    T operator()(const T& x, const T& y) const;
75};
76
77template <class T>
78struct minus : binary_function<T, T, T>
79{
80    T operator()(const T& x, const T& y) const;
81};
82
83template <class T>
84struct multiplies : binary_function<T, T, T>
85{
86    T operator()(const T& x, const T& y) const;
87};
88
89template <class T>
90struct divides : binary_function<T, T, T>
91{
92    T operator()(const T& x, const T& y) const;
93};
94
95template <class T>
96struct modulus : binary_function<T, T, T>
97{
98    T operator()(const T& x, const T& y) const;
99};
100
101template <class T>
102struct negate : unary_function<T, T>
103{
104    T operator()(const T& x) const;
105};
106
107template <class T>
108struct equal_to : binary_function<T, T, bool>
109{
110    bool operator()(const T& x, const T& y) const;
111};
112
113template <class T>
114struct not_equal_to : binary_function<T, T, bool>
115{
116    bool operator()(const T& x, const T& y) const;
117};
118
119template <class T>
120struct greater : binary_function<T, T, bool>
121{
122    bool operator()(const T& x, const T& y) const;
123};
124
125template <class T>
126struct less : binary_function<T, T, bool>
127{
128    bool operator()(const T& x, const T& y) const;
129};
130
131template <class T>
132struct greater_equal : binary_function<T, T, bool>
133{
134    bool operator()(const T& x, const T& y) const;
135};
136
137template <class T>
138struct less_equal : binary_function<T, T, bool>
139{
140    bool operator()(const T& x, const T& y) const;
141};
142
143template <class T>
144struct logical_and : binary_function<T, T, bool>
145{
146    bool operator()(const T& x, const T& y) const;
147};
148
149template <class T>
150struct logical_or : binary_function<T, T, bool>
151{
152    bool operator()(const T& x, const T& y) const;
153};
154
155template <class T>
156struct logical_not : unary_function<T, bool>
157{
158    bool operator()(const T& x) const;
159};
160
161template <class Predicate>
162class unary_negate
163    : public unary_function<typename Predicate::argument_type, bool>
164{
165public:
166    explicit unary_negate(const Predicate& pred);
167    bool operator()(const typename Predicate::argument_type& x) const;
168};
169
170template <class Predicate> unary_negate<Predicate> not1(const Predicate& pred);
171
172template <class Predicate>
173class binary_negate
174    : public binary_function<typename Predicate::first_argument_type,
175                             typename Predicate::second_argument_type,
176                             bool>
177{
178public:
179    explicit binary_negate(const Predicate& pred);
180    bool operator()(const typename Predicate::first_argument_type& x,
181                    const typename Predicate::second_argument_type& y) const;
182};
183
184template <class Predicate> binary_negate<Predicate> not2(const Predicate& pred);
185
186template<class T> struct is_bind_expression;
187template<class T> struct is_placeholder;
188
189template<class Fn, class... BoundArgs>
190  unspecified bind(Fn&&, BoundArgs&&...);
191template<class R, class Fn, class... BoundArgs>
192  unspecified bind(Fn&&, BoundArgs&&...);
193
194namespace placeholders {
195  // M is the implementation-defined number of placeholders
196  extern unspecified _1;
197  extern unspecified _2;
198  .
199  .
200  .
201  extern unspecified _Mp;
202}
203
204template <class Operation>
205class binder1st
206    : public unary_function<typename Operation::second_argument_type,
207                            typename Operation::result_type>
208{
209protected:
210    Operation                               op;
211    typename Operation::first_argument_type value;
212public:
213    binder1st(const Operation& x, const typename Operation::first_argument_type y);
214    typename Operation::result_type operator()(      typename Operation::second_argument_type& x) const;
215    typename Operation::result_type operator()(const typename Operation::second_argument_type& x) const;
216};
217
218template <class Operation, class T>
219binder1st<Operation> bind1st(const Operation& op, const T& x);
220
221template <class Operation>
222class binder2nd
223    : public unary_function<typename Operation::first_argument_type,
224                            typename Operation::result_type>
225{
226protected:
227    Operation                                op;
228    typename Operation::second_argument_type value;
229public:
230    binder2nd(const Operation& x, const typename Operation::second_argument_type y);
231    typename Operation::result_type operator()(      typename Operation::first_argument_type& x) const;
232    typename Operation::result_type operator()(const typename Operation::first_argument_type& x) const;
233};
234
235template <class Operation, class T>
236binder2nd<Operation> bind2nd(const Operation& op, const T& x);
237
238template <class Arg, class Result>
239class pointer_to_unary_function : public unary_function<Arg, Result>
240{
241public:
242    explicit pointer_to_unary_function(Result (*f)(Arg));
243    Result operator()(Arg x) const;
244};
245
246template <class Arg, class Result>
247pointer_to_unary_function<Arg,Result> ptr_fun(Result (*f)(Arg));
248
249template <class Arg1, class Arg2, class Result>
250class pointer_to_binary_function : public binary_function<Arg1, Arg2, Result>
251{
252public:
253    explicit pointer_to_binary_function(Result (*f)(Arg1, Arg2));
254    Result operator()(Arg1 x, Arg2 y) const;
255};
256
257template <class Arg1, class Arg2, class Result>
258pointer_to_binary_function<Arg1,Arg2,Result> ptr_fun(Result (*f)(Arg1,Arg2));
259
260template<class S, class T>
261class mem_fun_t : public unary_function<T*, S>
262{
263public:
264    explicit mem_fun_t(S (T::*p)());
265    S operator()(T* p) const;
266};
267
268template<class S, class T, class A>
269class mem_fun1_t : public binary_function<T*, A, S>
270{
271public:
272    explicit mem_fun1_t(S (T::*p)(A));
273    S operator()(T* p, A x) const;
274};
275
276template<class S, class T>          mem_fun_t<S,T>    mem_fun(S (T::*f)());
277template<class S, class T, class A> mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A));
278
279template<class S, class T>
280class mem_fun_ref_t : public unary_function<T, S>
281{
282public:
283    explicit mem_fun_ref_t(S (T::*p)());
284    S operator()(T& p) const;
285};
286
287template<class S, class T, class A>
288class mem_fun1_ref_t : public binary_function<T, A, S>
289{
290public:
291    explicit mem_fun1_ref_t(S (T::*p)(A));
292    S operator()(T& p, A x) const;
293};
294
295template<class S, class T>          mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)());
296template<class S, class T, class A> mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A));
297
298template <class S, class T>
299class const_mem_fun_t : public unary_function<const T*, S>
300{
301public:
302    explicit const_mem_fun_t(S (T::*p)() const);
303    S operator()(const T* p) const;
304};
305
306template <class S, class T, class A>
307class const_mem_fun1_t : public binary_function<const T*, A, S>
308{
309public:
310    explicit const_mem_fun1_t(S (T::*p)(A) const);
311    S operator()(const T* p, A x) const;
312};
313
314template <class S, class T>          const_mem_fun_t<S,T>    mem_fun(S (T::*f)() const);
315template <class S, class T, class A> const_mem_fun1_t<S,T,A> mem_fun(S (T::*f)(A) const);
316
317template <class S, class T>
318class const_mem_fun_ref_t : public unary_function<T, S>
319{
320public:
321    explicit const_mem_fun_ref_t(S (T::*p)() const);
322    S operator()(const T& p) const;
323};
324
325template <class S, class T, class A>
326class const_mem_fun1_ref_t : public binary_function<T, A, S>
327{
328public:
329    explicit const_mem_fun1_ref_t(S (T::*p)(A) const);
330    S operator()(const T& p, A x) const;
331};
332
333template <class S, class T>          const_mem_fun_ref_t<S,T>    mem_fun_ref(S (T::*f)() const);
334template <class S, class T, class A> const_mem_fun1_ref_t<S,T,A> mem_fun_ref(S (T::*f)(A) const);
335
336template<class R, class T> unspecified mem_fn(R T::*);
337template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...));
338template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const);
339template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) volatile);
340template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const volatile);
341template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) &);
342template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const &);
343template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) volatile &);
344template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const volatile &);
345template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) &&);
346template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const &&);
347template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) volatile &&);
348template<class R, class T, class... Args> unspecified mem_fn(R (T::*)(Args...) const volatile &&);
349
350class bad_function_call
351    : public exception
352{
353};
354
355template<class> class function; // undefined
356
357template<class R, class... ArgTypes>
358class function<R(ArgTypes...)>
359  : public unary_function<T1, R>      // iff sizeof...(ArgTypes) == 1 and
360                                      // ArgTypes contains T1
361  : public binary_function<T1, T2, R> // iff sizeof...(ArgTypes) == 2 and
362                                      // ArgTypes contains T1 and T2
363{
364public:
365    typedef R result_type;
366
367    // construct/copy/destroy:
368    function() noexcept;
369    function(nullptr_t) noexcept;
370    function(const function&);
371    function(function&&) noexcept;
372    template<class F>
373      function(F);
374    template<Allocator Alloc>
375      function(allocator_arg_t, const Alloc&) noexcept;
376    template<Allocator Alloc>
377      function(allocator_arg_t, const Alloc&, nullptr_t) noexcept;
378    template<Allocator Alloc>
379      function(allocator_arg_t, const Alloc&, const function&);
380    template<Allocator Alloc>
381      function(allocator_arg_t, const Alloc&, function&&);
382    template<class F, Allocator Alloc>
383      function(allocator_arg_t, const Alloc&, F);
384
385    function& operator=(const function&);
386    function& operator=(function&&) noexcept;
387    function& operator=(nullptr_t) noexcept;
388    template<class F>
389      function& operator=(F&&);
390    template<class F>
391      function& operator=(reference_wrapper<F>) noexcept;
392
393    ~function();
394
395    // function modifiers:
396    void swap(function&) noexcept;
397    template<class F, class Alloc>
398      void assign(F&&, const Alloc&);
399
400    // function capacity:
401    explicit operator bool() const noexcept;
402
403    // function invocation:
404    R operator()(ArgTypes...) const;
405
406    // function target access:
407    const std::type_info& target_type() const noexcept;
408    template <typename T>       T* target() noexcept;
409    template <typename T> const T* target() const noexcept;
410};
411
412// Null pointer comparisons:
413template <class R, class ... ArgTypes>
414  bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
415
416template <class R, class ... ArgTypes>
417  bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
418
419template <class R, class ... ArgTypes>
420  bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
421
422template <class  R, class ... ArgTypes>
423  bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
424
425// specialized algorithms:
426template <class  R, class ... ArgTypes>
427  void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&) noexcept;
428
429template <class T> struct hash;
430
431template <> struct hash<bool>;
432template <> struct hash<char>;
433template <> struct hash<signed char>;
434template <> struct hash<unsigned char>;
435template <> struct hash<char16_t>;
436template <> struct hash<char32_t>;
437template <> struct hash<wchar_t>;
438template <> struct hash<short>;
439template <> struct hash<unsigned short>;
440template <> struct hash<int>;
441template <> struct hash<unsigned int>;
442template <> struct hash<long>;
443template <> struct hash<long long>;
444template <> struct hash<unsigned long>;
445template <> struct hash<unsigned long long>;
446
447template <> struct hash<float>;
448template <> struct hash<double>;
449template <> struct hash<long double>;
450
451template<class T> struct hash<T*>;
452
453}  // std
454
455POLICY:  For non-variadic implementations, the number of arguments is limited
456         to 3.  It is hoped that the need for non-variadic implementations
457         will be minimal.
458
459*/
460
461#include <__config>
462#include <type_traits>
463#include <typeinfo>
464#include <exception>
465#include <memory>
466#include <tuple>
467
468#include <__functional_base>
469
470#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
471#pragma GCC system_header
472#endif
473
474_LIBCPP_BEGIN_NAMESPACE_STD
475
476template <class _Tp>
477struct _LIBCPP_VISIBLE plus : binary_function<_Tp, _Tp, _Tp>
478{
479    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
480        {return __x + __y;}
481};
482
483template <class _Tp>
484struct _LIBCPP_VISIBLE minus : binary_function<_Tp, _Tp, _Tp>
485{
486    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
487        {return __x - __y;}
488};
489
490template <class _Tp>
491struct _LIBCPP_VISIBLE multiplies : binary_function<_Tp, _Tp, _Tp>
492{
493    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
494        {return __x * __y;}
495};
496
497template <class _Tp>
498struct _LIBCPP_VISIBLE divides : binary_function<_Tp, _Tp, _Tp>
499{
500    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
501        {return __x / __y;}
502};
503
504template <class _Tp>
505struct _LIBCPP_VISIBLE modulus : binary_function<_Tp, _Tp, _Tp>
506{
507    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
508        {return __x % __y;}
509};
510
511template <class _Tp>
512struct _LIBCPP_VISIBLE negate : unary_function<_Tp, _Tp>
513{
514    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x) const
515        {return -__x;}
516};
517
518template <class _Tp>
519struct _LIBCPP_VISIBLE equal_to : binary_function<_Tp, _Tp, bool>
520{
521    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
522        {return __x == __y;}
523};
524
525template <class _Tp>
526struct _LIBCPP_VISIBLE not_equal_to : binary_function<_Tp, _Tp, bool>
527{
528    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
529        {return __x != __y;}
530};
531
532template <class _Tp>
533struct _LIBCPP_VISIBLE greater : binary_function<_Tp, _Tp, bool>
534{
535    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
536        {return __x > __y;}
537};
538
539// less in <__functional_base>
540
541template <class _Tp>
542struct _LIBCPP_VISIBLE greater_equal : binary_function<_Tp, _Tp, bool>
543{
544    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
545        {return __x >= __y;}
546};
547
548template <class _Tp>
549struct _LIBCPP_VISIBLE less_equal : binary_function<_Tp, _Tp, bool>
550{
551    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
552        {return __x <= __y;}
553};
554
555template <class _Tp>
556struct _LIBCPP_VISIBLE logical_and : binary_function<_Tp, _Tp, bool>
557{
558    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
559        {return __x && __y;}
560};
561
562template <class _Tp>
563struct _LIBCPP_VISIBLE logical_or : binary_function<_Tp, _Tp, bool>
564{
565    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x, const _Tp& __y) const
566        {return __x || __y;}
567};
568
569template <class _Tp>
570struct _LIBCPP_VISIBLE logical_not : unary_function<_Tp, bool>
571{
572    _LIBCPP_INLINE_VISIBILITY bool operator()(const _Tp& __x) const
573        {return !__x;}
574};
575
576template <class _Tp>
577struct _LIBCPP_VISIBLE bit_and : binary_function<_Tp, _Tp, _Tp>
578{
579    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
580        {return __x & __y;}
581};
582
583template <class _Tp>
584struct _LIBCPP_VISIBLE bit_or : binary_function<_Tp, _Tp, _Tp>
585{
586    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
587        {return __x | __y;}
588};
589
590template <class _Tp>
591struct _LIBCPP_VISIBLE bit_xor : binary_function<_Tp, _Tp, _Tp>
592{
593    _LIBCPP_INLINE_VISIBILITY _Tp operator()(const _Tp& __x, const _Tp& __y) const
594        {return __x ^ __y;}
595};
596
597template <class _Predicate>
598class _LIBCPP_VISIBLE unary_negate
599    : public unary_function<typename _Predicate::argument_type, bool>
600{
601    _Predicate __pred_;
602public:
603    _LIBCPP_INLINE_VISIBILITY explicit unary_negate(const _Predicate& __pred)
604        : __pred_(__pred) {}
605    _LIBCPP_INLINE_VISIBILITY bool operator()(const typename _Predicate::argument_type& __x) const
606        {return !__pred_(__x);}
607};
608
609template <class _Predicate>
610inline _LIBCPP_INLINE_VISIBILITY
611unary_negate<_Predicate>
612not1(const _Predicate& __pred) {return unary_negate<_Predicate>(__pred);}
613
614template <class _Predicate>
615class _LIBCPP_VISIBLE binary_negate
616    : public binary_function<typename _Predicate::first_argument_type,
617                             typename _Predicate::second_argument_type,
618                             bool>
619{
620    _Predicate __pred_;
621public:
622    _LIBCPP_INLINE_VISIBILITY explicit binary_negate(const _Predicate& __pred)
623        : __pred_(__pred) {}
624    _LIBCPP_INLINE_VISIBILITY bool operator()(const typename _Predicate::first_argument_type& __x,
625                    const typename _Predicate::second_argument_type& __y) const
626        {return !__pred_(__x, __y);}
627};
628
629template <class _Predicate>
630inline _LIBCPP_INLINE_VISIBILITY
631binary_negate<_Predicate>
632not2(const _Predicate& __pred) {return binary_negate<_Predicate>(__pred);}
633
634template <class __Operation>
635class _LIBCPP_VISIBLE binder1st
636    : public unary_function<typename __Operation::second_argument_type,
637                            typename __Operation::result_type>
638{
639protected:
640    __Operation                               op;
641    typename __Operation::first_argument_type value;
642public:
643    _LIBCPP_INLINE_VISIBILITY binder1st(const __Operation& __x,
644                               const typename __Operation::first_argument_type __y)
645        : op(__x), value(__y) {}
646    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
647        (typename __Operation::second_argument_type& __x) const
648            {return op(value, __x);}
649    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
650        (const typename __Operation::second_argument_type& __x) const
651            {return op(value, __x);}
652};
653
654template <class __Operation, class _Tp>
655inline _LIBCPP_INLINE_VISIBILITY
656binder1st<__Operation>
657bind1st(const __Operation& __op, const _Tp& __x)
658    {return binder1st<__Operation>(__op, __x);}
659
660template <class __Operation>
661class _LIBCPP_VISIBLE binder2nd
662    : public unary_function<typename __Operation::first_argument_type,
663                            typename __Operation::result_type>
664{
665protected:
666    __Operation                                op;
667    typename __Operation::second_argument_type value;
668public:
669    _LIBCPP_INLINE_VISIBILITY
670    binder2nd(const __Operation& __x, const typename __Operation::second_argument_type __y)
671        : op(__x), value(__y) {}
672    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
673        (      typename __Operation::first_argument_type& __x) const
674            {return op(__x, value);}
675    _LIBCPP_INLINE_VISIBILITY typename __Operation::result_type operator()
676        (const typename __Operation::first_argument_type& __x) const
677            {return op(__x, value);}
678};
679
680template <class __Operation, class _Tp>
681inline _LIBCPP_INLINE_VISIBILITY
682binder2nd<__Operation>
683bind2nd(const __Operation& __op, const _Tp& __x)
684    {return binder2nd<__Operation>(__op, __x);}
685
686template <class _Arg, class _Result>
687class _LIBCPP_VISIBLE pointer_to_unary_function
688    : public unary_function<_Arg, _Result>
689{
690    _Result (*__f_)(_Arg);
691public:
692    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_unary_function(_Result (*__f)(_Arg))
693        : __f_(__f) {}
694    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg __x) const
695        {return __f_(__x);}
696};
697
698template <class _Arg, class _Result>
699inline _LIBCPP_INLINE_VISIBILITY
700pointer_to_unary_function<_Arg,_Result>
701ptr_fun(_Result (*__f)(_Arg))
702    {return pointer_to_unary_function<_Arg,_Result>(__f);}
703
704template <class _Arg1, class _Arg2, class _Result>
705class _LIBCPP_VISIBLE pointer_to_binary_function
706    : public binary_function<_Arg1, _Arg2, _Result>
707{
708    _Result (*__f_)(_Arg1, _Arg2);
709public:
710    _LIBCPP_INLINE_VISIBILITY explicit pointer_to_binary_function(_Result (*__f)(_Arg1, _Arg2))
711        : __f_(__f) {}
712    _LIBCPP_INLINE_VISIBILITY _Result operator()(_Arg1 __x, _Arg2 __y) const
713        {return __f_(__x, __y);}
714};
715
716template <class _Arg1, class _Arg2, class _Result>
717inline _LIBCPP_INLINE_VISIBILITY
718pointer_to_binary_function<_Arg1,_Arg2,_Result>
719ptr_fun(_Result (*__f)(_Arg1,_Arg2))
720    {return pointer_to_binary_function<_Arg1,_Arg2,_Result>(__f);}
721
722template<class _Sp, class _Tp>
723class _LIBCPP_VISIBLE mem_fun_t : public unary_function<_Tp*, _Sp>
724{
725    _Sp (_Tp::*__p_)();
726public:
727    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_t(_Sp (_Tp::*__p)())
728        : __p_(__p) {}
729    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p) const
730        {return (__p->*__p_)();}
731};
732
733template<class _Sp, class _Tp, class _Ap>
734class _LIBCPP_VISIBLE mem_fun1_t : public binary_function<_Tp*, _Ap, _Sp>
735{
736    _Sp (_Tp::*__p_)(_Ap);
737public:
738    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_t(_Sp (_Tp::*__p)(_Ap))
739        : __p_(__p) {}
740    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp* __p, _Ap __x) const
741        {return (__p->*__p_)(__x);}
742};
743
744template<class _Sp, class _Tp>
745inline _LIBCPP_INLINE_VISIBILITY
746mem_fun_t<_Sp,_Tp>
747mem_fun(_Sp (_Tp::*__f)())
748    {return mem_fun_t<_Sp,_Tp>(__f);}
749
750template<class _Sp, class _Tp, class _Ap>
751inline _LIBCPP_INLINE_VISIBILITY
752mem_fun1_t<_Sp,_Tp,_Ap>
753mem_fun(_Sp (_Tp::*__f)(_Ap))
754    {return mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
755
756template<class _Sp, class _Tp>
757class _LIBCPP_VISIBLE mem_fun_ref_t : public unary_function<_Tp, _Sp>
758{
759    _Sp (_Tp::*__p_)();
760public:
761    _LIBCPP_INLINE_VISIBILITY explicit mem_fun_ref_t(_Sp (_Tp::*__p)())
762        : __p_(__p) {}
763    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p) const
764        {return (__p.*__p_)();}
765};
766
767template<class _Sp, class _Tp, class _Ap>
768class _LIBCPP_VISIBLE mem_fun1_ref_t : public binary_function<_Tp, _Ap, _Sp>
769{
770    _Sp (_Tp::*__p_)(_Ap);
771public:
772    _LIBCPP_INLINE_VISIBILITY explicit mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap))
773        : __p_(__p) {}
774    _LIBCPP_INLINE_VISIBILITY _Sp operator()(_Tp& __p, _Ap __x) const
775        {return (__p.*__p_)(__x);}
776};
777
778template<class _Sp, class _Tp>
779inline _LIBCPP_INLINE_VISIBILITY
780mem_fun_ref_t<_Sp,_Tp>
781mem_fun_ref(_Sp (_Tp::*__f)())
782    {return mem_fun_ref_t<_Sp,_Tp>(__f);}
783
784template<class _Sp, class _Tp, class _Ap>
785inline _LIBCPP_INLINE_VISIBILITY
786mem_fun1_ref_t<_Sp,_Tp,_Ap>
787mem_fun_ref(_Sp (_Tp::*__f)(_Ap))
788    {return mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
789
790template <class _Sp, class _Tp>
791class _LIBCPP_VISIBLE const_mem_fun_t : public unary_function<const _Tp*, _Sp>
792{
793    _Sp (_Tp::*__p_)() const;
794public:
795    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_t(_Sp (_Tp::*__p)() const)
796        : __p_(__p) {}
797    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p) const
798        {return (__p->*__p_)();}
799};
800
801template <class _Sp, class _Tp, class _Ap>
802class _LIBCPP_VISIBLE const_mem_fun1_t : public binary_function<const _Tp*, _Ap, _Sp>
803{
804    _Sp (_Tp::*__p_)(_Ap) const;
805public:
806    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_t(_Sp (_Tp::*__p)(_Ap) const)
807        : __p_(__p) {}
808    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp* __p, _Ap __x) const
809        {return (__p->*__p_)(__x);}
810};
811
812template <class _Sp, class _Tp>
813inline _LIBCPP_INLINE_VISIBILITY
814const_mem_fun_t<_Sp,_Tp>
815mem_fun(_Sp (_Tp::*__f)() const)
816    {return const_mem_fun_t<_Sp,_Tp>(__f);}
817
818template <class _Sp, class _Tp, class _Ap>
819inline _LIBCPP_INLINE_VISIBILITY
820const_mem_fun1_t<_Sp,_Tp,_Ap>
821mem_fun(_Sp (_Tp::*__f)(_Ap) const)
822    {return const_mem_fun1_t<_Sp,_Tp,_Ap>(__f);}
823
824template <class _Sp, class _Tp>
825class _LIBCPP_VISIBLE const_mem_fun_ref_t : public unary_function<_Tp, _Sp>
826{
827    _Sp (_Tp::*__p_)() const;
828public:
829    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun_ref_t(_Sp (_Tp::*__p)() const)
830        : __p_(__p) {}
831    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p) const
832        {return (__p.*__p_)();}
833};
834
835template <class _Sp, class _Tp, class _Ap>
836class _LIBCPP_VISIBLE const_mem_fun1_ref_t
837    : public binary_function<_Tp, _Ap, _Sp>
838{
839    _Sp (_Tp::*__p_)(_Ap) const;
840public:
841    _LIBCPP_INLINE_VISIBILITY explicit const_mem_fun1_ref_t(_Sp (_Tp::*__p)(_Ap) const)
842        : __p_(__p) {}
843    _LIBCPP_INLINE_VISIBILITY _Sp operator()(const _Tp& __p, _Ap __x) const
844        {return (__p.*__p_)(__x);}
845};
846
847template <class _Sp, class _Tp>
848inline _LIBCPP_INLINE_VISIBILITY
849const_mem_fun_ref_t<_Sp,_Tp>
850mem_fun_ref(_Sp (_Tp::*__f)() const)
851    {return const_mem_fun_ref_t<_Sp,_Tp>(__f);}
852
853template <class _Sp, class _Tp, class _Ap>
854inline _LIBCPP_INLINE_VISIBILITY
855const_mem_fun1_ref_t<_Sp,_Tp,_Ap>
856mem_fun_ref(_Sp (_Tp::*__f)(_Ap) const)
857    {return const_mem_fun1_ref_t<_Sp,_Tp,_Ap>(__f);}
858
859#ifdef _LIBCPP_HAS_NO_VARIADICS
860
861#include <__functional_03>
862
863#else  // _LIBCPP_HAS_NO_VARIADICS
864
865template <class _Tp>
866class __mem_fn
867    : public __weak_result_type<_Tp>
868{
869public:
870    // types
871    typedef _Tp type;
872private:
873    type __f_;
874
875public:
876    _LIBCPP_INLINE_VISIBILITY __mem_fn(type __f) : __f_(__f) {}
877
878    // invoke
879    template <class... _ArgTypes>
880       _LIBCPP_INLINE_VISIBILITY
881       typename __invoke_return<type, _ArgTypes...>::type
882          operator() (_ArgTypes&&... __args)
883          {
884              return __invoke(__f_, _VSTD::forward<_ArgTypes>(__args)...);
885          }
886};
887
888template<class _Rp, class _Tp>
889inline _LIBCPP_INLINE_VISIBILITY
890__mem_fn<_Rp _Tp::*>
891mem_fn(_Rp _Tp::* __pm)
892{
893    return __mem_fn<_Rp _Tp::*>(__pm);
894}
895
896template<class _Rp, class _Tp, class ..._Args>
897inline _LIBCPP_INLINE_VISIBILITY
898__mem_fn<_Rp (_Tp::*)(_Args...)>
899mem_fn(_Rp (_Tp::* __pm)(_Args...))
900{
901    return __mem_fn<_Rp (_Tp::*)(_Args...)>(__pm);
902}
903
904template<class _Rp, class _Tp, class ..._Args>
905inline _LIBCPP_INLINE_VISIBILITY
906__mem_fn<_Rp (_Tp::*)(_Args...) const>
907mem_fn(_Rp (_Tp::* __pm)(_Args...) const)
908{
909    return __mem_fn<_Rp (_Tp::*)(_Args...) const>(__pm);
910}
911
912template<class _Rp, class _Tp, class ..._Args>
913inline _LIBCPP_INLINE_VISIBILITY
914__mem_fn<_Rp (_Tp::*)(_Args...) volatile>
915mem_fn(_Rp (_Tp::* __pm)(_Args...) volatile)
916{
917    return __mem_fn<_Rp (_Tp::*)(_Args...) volatile>(__pm);
918}
919
920template<class _Rp, class _Tp, class ..._Args>
921inline _LIBCPP_INLINE_VISIBILITY
922__mem_fn<_Rp (_Tp::*)(_Args...) const volatile>
923mem_fn(_Rp (_Tp::* __pm)(_Args...) const volatile)
924{
925    return __mem_fn<_Rp (_Tp::*)(_Args...) const volatile>(__pm);
926}
927
928// bad_function_call
929
930class _LIBCPP_EXCEPTION_ABI bad_function_call
931    : public exception
932{
933};
934
935template<class _Fp> class _LIBCPP_VISIBLE function; // undefined
936
937namespace __function
938{
939
940template<class _Rp, class ..._ArgTypes>
941struct __maybe_derive_from_unary_function
942{
943};
944
945template<class _Rp, class _A1>
946struct __maybe_derive_from_unary_function<_Rp(_A1)>
947    : public unary_function<_A1, _Rp>
948{
949};
950
951template<class _Rp, class ..._ArgTypes>
952struct __maybe_derive_from_binary_function
953{
954};
955
956template<class _Rp, class _A1, class _A2>
957struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)>
958    : public binary_function<_A1, _A2, _Rp>
959{
960};
961
962template<class _Fp> class __base;
963
964template<class _Rp, class ..._ArgTypes>
965class __base<_Rp(_ArgTypes...)>
966{
967    __base(const __base&);
968    __base& operator=(const __base&);
969public:
970    _LIBCPP_INLINE_VISIBILITY __base() {}
971    _LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
972    virtual __base* __clone() const = 0;
973    virtual void __clone(__base*) const = 0;
974    virtual void destroy() _NOEXCEPT = 0;
975    virtual void destroy_deallocate() _NOEXCEPT = 0;
976    virtual _Rp operator()(_ArgTypes&& ...) = 0;
977#ifndef _LIBCPP_NO_RTTI
978    virtual const void* target(const type_info&) const _NOEXCEPT = 0;
979    virtual const std::type_info& target_type() const _NOEXCEPT = 0;
980#endif  // _LIBCPP_NO_RTTI
981};
982
983template<class _FD, class _Alloc, class _FB> class __func;
984
985template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
986class __func<_Fp, _Alloc, _Rp(_ArgTypes...)>
987    : public  __base<_Rp(_ArgTypes...)>
988{
989    __compressed_pair<_Fp, _Alloc> __f_;
990public:
991    _LIBCPP_INLINE_VISIBILITY
992    explicit __func(_Fp&& __f)
993        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
994                                    _VSTD::forward_as_tuple()) {}
995    _LIBCPP_INLINE_VISIBILITY
996    explicit __func(const _Fp& __f, const _Alloc& __a)
997        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
998                                    _VSTD::forward_as_tuple(__a)) {}
999
1000    _LIBCPP_INLINE_VISIBILITY
1001    explicit __func(const _Fp& __f, _Alloc&& __a)
1002        : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
1003                                    _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
1004
1005    _LIBCPP_INLINE_VISIBILITY
1006    explicit __func(_Fp&& __f, _Alloc&& __a)
1007        : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
1008                                    _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
1009    virtual __base<_Rp(_ArgTypes...)>* __clone() const;
1010    virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
1011    virtual void destroy() _NOEXCEPT;
1012    virtual void destroy_deallocate() _NOEXCEPT;
1013    virtual _Rp operator()(_ArgTypes&& ... __arg);
1014#ifndef _LIBCPP_NO_RTTI
1015    virtual const void* target(const type_info&) const _NOEXCEPT;
1016    virtual const std::type_info& target_type() const _NOEXCEPT;
1017#endif  // _LIBCPP_NO_RTTI
1018};
1019
1020template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1021__base<_Rp(_ArgTypes...)>*
1022__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone() const
1023{
1024    typedef typename _Alloc::template rebind<__func>::other _Ap;
1025    _Ap __a(__f_.second());
1026    typedef __allocator_destructor<_Ap> _Dp;
1027    unique_ptr<__func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1028    ::new (__hold.get()) __func(__f_.first(), _Alloc(__a));
1029    return __hold.release();
1030}
1031
1032template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1033void
1034__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const
1035{
1036    ::new (__p) __func(__f_.first(), __f_.second());
1037}
1038
1039template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1040void
1041__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() _NOEXCEPT
1042{
1043    __f_.~__compressed_pair<_Fp, _Alloc>();
1044}
1045
1046template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1047void
1048__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() _NOEXCEPT
1049{
1050    typedef typename _Alloc::template rebind<__func>::other _Ap;
1051    _Ap __a(__f_.second());
1052    __f_.~__compressed_pair<_Fp, _Alloc>();
1053    __a.deallocate(this, 1);
1054}
1055
1056template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1057_Rp
1058__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
1059{
1060    return __invoke(__f_.first(), _VSTD::forward<_ArgTypes>(__arg)...);
1061}
1062
1063#ifndef _LIBCPP_NO_RTTI
1064
1065template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1066const void*
1067__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target(const type_info& __ti) const _NOEXCEPT
1068{
1069    if (__ti == typeid(_Fp))
1070        return &__f_.first();
1071    return (const void*)0;
1072}
1073
1074template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
1075const std::type_info&
1076__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
1077{
1078    return typeid(_Fp);
1079}
1080
1081#endif  // _LIBCPP_NO_RTTI
1082
1083}  // __function
1084
1085template<class _Rp, class ..._ArgTypes>
1086class _LIBCPP_VISIBLE function<_Rp(_ArgTypes...)>
1087    : public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
1088      public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
1089{
1090    typedef __function::__base<_Rp(_ArgTypes...)> __base;
1091    aligned_storage<3*sizeof(void*)>::type __buf_;
1092    __base* __f_;
1093
1094    template <class _Fp>
1095        _LIBCPP_INLINE_VISIBILITY
1096        static bool __not_null(const _Fp&) {return true;}
1097    template <class _R2, class ..._Ap>
1098        _LIBCPP_INLINE_VISIBILITY
1099        static bool __not_null(_R2 (*__p)(_Ap...)) {return __p;}
1100    template <class _R2, class _Cp, class ..._Ap>
1101        _LIBCPP_INLINE_VISIBILITY
1102        static bool __not_null(_R2 (_Cp::*__p)(_Ap...)) {return __p;}
1103    template <class _R2, class _Cp, class ..._Ap>
1104        _LIBCPP_INLINE_VISIBILITY
1105        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) const) {return __p;}
1106    template <class _R2, class _Cp, class ..._Ap>
1107        _LIBCPP_INLINE_VISIBILITY
1108        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) volatile) {return __p;}
1109    template <class _R2, class _Cp, class ..._Ap>
1110        _LIBCPP_INLINE_VISIBILITY
1111        static bool __not_null(_R2 (_Cp::*__p)(_Ap...) const volatile) {return __p;}
1112    template <class _R2, class ..._Ap>
1113        _LIBCPP_INLINE_VISIBILITY
1114        static bool __not_null(const function<_Rp(_Ap...)>& __p) {return __p;}
1115
1116    template <class _Fp, bool = __invokable<_Fp&, _ArgTypes...>::value>
1117        struct __callable;
1118    template <class _Fp>
1119        struct __callable<_Fp, true>
1120        {
1121            static const bool value =
1122                is_convertible<typename __invoke_of<_Fp&, _ArgTypes...>::type,
1123                               _Rp>::value;
1124        };
1125    template <class _Fp>
1126        struct __callable<_Fp, false>
1127        {
1128            static const bool value = false;
1129        };
1130public:
1131    typedef _Rp result_type;
1132
1133    // construct/copy/destroy:
1134    _LIBCPP_INLINE_VISIBILITY
1135    function() _NOEXCEPT : __f_(0) {}
1136    _LIBCPP_INLINE_VISIBILITY
1137    function(nullptr_t) _NOEXCEPT : __f_(0) {}
1138    function(const function&);
1139    function(function&&) _NOEXCEPT;
1140    template<class _Fp>
1141      function(_Fp,
1142               typename enable_if<__callable<_Fp>::value>::type* = 0);
1143
1144    template<class _Alloc>
1145      _LIBCPP_INLINE_VISIBILITY
1146      function(allocator_arg_t, const _Alloc&) _NOEXCEPT : __f_(0) {}
1147    template<class _Alloc>
1148      _LIBCPP_INLINE_VISIBILITY
1149      function(allocator_arg_t, const _Alloc&, nullptr_t) _NOEXCEPT : __f_(0) {}
1150    template<class _Alloc>
1151      function(allocator_arg_t, const _Alloc&, const function&);
1152    template<class _Alloc>
1153      function(allocator_arg_t, const _Alloc&, function&&);
1154    template<class _Fp, class _Alloc>
1155      function(allocator_arg_t, const _Alloc& __a, _Fp __f,
1156               typename enable_if<__callable<_Fp>::value>::type* = 0);
1157
1158    function& operator=(const function&);
1159    function& operator=(function&&) _NOEXCEPT;
1160    function& operator=(nullptr_t) _NOEXCEPT;
1161    template<class _Fp>
1162      typename enable_if
1163      <
1164        __callable<typename decay<_Fp>::type>::value,
1165        function&
1166      >::type
1167      operator=(_Fp&&);
1168
1169    ~function();
1170
1171    // function modifiers:
1172    void swap(function&) _NOEXCEPT;
1173    template<class _Fp, class _Alloc>
1174      _LIBCPP_INLINE_VISIBILITY
1175      void assign(_Fp&& __f, const _Alloc& __a)
1176        {function(allocator_arg, __a, _VSTD::forward<_Fp>(__f)).swap(*this);}
1177
1178    // function capacity:
1179    _LIBCPP_INLINE_VISIBILITY
1180        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return __f_;}
1181
1182    // deleted overloads close possible hole in the type system
1183    template<class _R2, class... _ArgTypes2>
1184      bool operator==(const function<_R2(_ArgTypes2...)>&) const = delete;
1185    template<class _R2, class... _ArgTypes2>
1186      bool operator!=(const function<_R2(_ArgTypes2...)>&) const = delete;
1187public:
1188    // function invocation:
1189    _Rp operator()(_ArgTypes...) const;
1190
1191#ifndef _LIBCPP_NO_RTTI
1192    // function target access:
1193    const std::type_info& target_type() const _NOEXCEPT;
1194    template <typename _Tp> _Tp* target() _NOEXCEPT;
1195    template <typename _Tp> const _Tp* target() const _NOEXCEPT;
1196#endif  // _LIBCPP_NO_RTTI
1197};
1198
1199template<class _Rp, class ..._ArgTypes>
1200function<_Rp(_ArgTypes...)>::function(const function& __f)
1201{
1202    if (__f.__f_ == 0)
1203        __f_ = 0;
1204    else if (__f.__f_ == (const __base*)&__f.__buf_)
1205    {
1206        __f_ = (__base*)&__buf_;
1207        __f.__f_->__clone(__f_);
1208    }
1209    else
1210        __f_ = __f.__f_->__clone();
1211}
1212
1213template<class _Rp, class ..._ArgTypes>
1214template <class _Alloc>
1215function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
1216                                     const function& __f)
1217{
1218    if (__f.__f_ == 0)
1219        __f_ = 0;
1220    else if (__f.__f_ == (const __base*)&__f.__buf_)
1221    {
1222        __f_ = (__base*)&__buf_;
1223        __f.__f_->__clone(__f_);
1224    }
1225    else
1226        __f_ = __f.__f_->__clone();
1227}
1228
1229template<class _Rp, class ..._ArgTypes>
1230function<_Rp(_ArgTypes...)>::function(function&& __f) _NOEXCEPT
1231{
1232    if (__f.__f_ == 0)
1233        __f_ = 0;
1234    else if (__f.__f_ == (__base*)&__f.__buf_)
1235    {
1236        __f_ = (__base*)&__buf_;
1237        __f.__f_->__clone(__f_);
1238    }
1239    else
1240    {
1241        __f_ = __f.__f_;
1242        __f.__f_ = 0;
1243    }
1244}
1245
1246template<class _Rp, class ..._ArgTypes>
1247template <class _Alloc>
1248function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc&,
1249                                     function&& __f)
1250{
1251    if (__f.__f_ == 0)
1252        __f_ = 0;
1253    else if (__f.__f_ == (__base*)&__f.__buf_)
1254    {
1255        __f_ = (__base*)&__buf_;
1256        __f.__f_->__clone(__f_);
1257    }
1258    else
1259    {
1260        __f_ = __f.__f_;
1261        __f.__f_ = 0;
1262    }
1263}
1264
1265template<class _Rp, class ..._ArgTypes>
1266template <class _Fp>
1267function<_Rp(_ArgTypes...)>::function(_Fp __f,
1268                                     typename enable_if<__callable<_Fp>::value>::type*)
1269    : __f_(0)
1270{
1271    if (__not_null(__f))
1272    {
1273        typedef __function::__func<_Fp, allocator<_Fp>, _Rp(_ArgTypes...)> _FF;
1274        if (sizeof(_FF) <= sizeof(__buf_) && is_nothrow_copy_constructible<_Fp>::value)
1275        {
1276            __f_ = (__base*)&__buf_;
1277            ::new (__f_) _FF(_VSTD::move(__f));
1278        }
1279        else
1280        {
1281            typedef allocator<_FF> _Ap;
1282            _Ap __a;
1283            typedef __allocator_destructor<_Ap> _Dp;
1284            unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1285            ::new (__hold.get()) _FF(_VSTD::move(__f), allocator<_Fp>(__a));
1286            __f_ = __hold.release();
1287        }
1288    }
1289}
1290
1291template<class _Rp, class ..._ArgTypes>
1292template <class _Fp, class _Alloc>
1293function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc& __a0, _Fp __f,
1294                                     typename enable_if<__callable<_Fp>::value>::type*)
1295    : __f_(0)
1296{
1297    typedef allocator_traits<_Alloc> __alloc_traits;
1298    if (__not_null(__f))
1299    {
1300        typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _FF;
1301        if (sizeof(_FF) <= sizeof(__buf_) && is_nothrow_copy_constructible<_Fp>::value)
1302        {
1303            __f_ = (__base*)&__buf_;
1304            ::new (__f_) _FF(_VSTD::move(__f));
1305        }
1306        else
1307        {
1308            typedef typename __alloc_traits::template
1309#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1310                rebind_alloc<_FF>
1311#else
1312                rebind_alloc<_FF>::other
1313#endif
1314                                                         _Ap;
1315            _Ap __a(__a0);
1316            typedef __allocator_destructor<_Ap> _Dp;
1317            unique_ptr<__base, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
1318            ::new (__hold.get()) _FF(_VSTD::move(__f), _Alloc(__a));
1319            __f_ = __hold.release();
1320        }
1321    }
1322}
1323
1324template<class _Rp, class ..._ArgTypes>
1325function<_Rp(_ArgTypes...)>&
1326function<_Rp(_ArgTypes...)>::operator=(const function& __f)
1327{
1328    function(__f).swap(*this);
1329    return *this;
1330}
1331
1332template<class _Rp, class ..._ArgTypes>
1333function<_Rp(_ArgTypes...)>&
1334function<_Rp(_ArgTypes...)>::operator=(function&& __f) _NOEXCEPT
1335{
1336    if (__f_ == (__base*)&__buf_)
1337        __f_->destroy();
1338    else if (__f_)
1339        __f_->destroy_deallocate();
1340    __f_ = 0;
1341    if (__f.__f_ == 0)
1342        __f_ = 0;
1343    else if (__f.__f_ == (__base*)&__f.__buf_)
1344    {
1345        __f_ = (__base*)&__buf_;
1346        __f.__f_->__clone(__f_);
1347    }
1348    else
1349    {
1350        __f_ = __f.__f_;
1351        __f.__f_ = 0;
1352    }
1353}
1354
1355template<class _Rp, class ..._ArgTypes>
1356function<_Rp(_ArgTypes...)>&
1357function<_Rp(_ArgTypes...)>::operator=(nullptr_t) _NOEXCEPT
1358{
1359    if (__f_ == (__base*)&__buf_)
1360        __f_->destroy();
1361    else if (__f_)
1362        __f_->destroy_deallocate();
1363    __f_ = 0;
1364}
1365
1366template<class _Rp, class ..._ArgTypes>
1367template <class _Fp>
1368typename enable_if
1369<
1370    function<_Rp(_ArgTypes...)>::template __callable<typename decay<_Fp>::type>::value,
1371    function<_Rp(_ArgTypes...)>&
1372>::type
1373function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f)
1374{
1375    function(_VSTD::forward<_Fp>(__f)).swap(*this);
1376    return *this;
1377}
1378
1379template<class _Rp, class ..._ArgTypes>
1380function<_Rp(_ArgTypes...)>::~function()
1381{
1382    if (__f_ == (__base*)&__buf_)
1383        __f_->destroy();
1384    else if (__f_)
1385        __f_->destroy_deallocate();
1386}
1387
1388template<class _Rp, class ..._ArgTypes>
1389void
1390function<_Rp(_ArgTypes...)>::swap(function& __f) _NOEXCEPT
1391{
1392    if (__f_ == (__base*)&__buf_ && __f.__f_ == (__base*)&__f.__buf_)
1393    {
1394        typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
1395        __base* __t = (__base*)&__tempbuf;
1396        __f_->__clone(__t);
1397        __f_->destroy();
1398        __f_ = 0;
1399        __f.__f_->__clone((__base*)&__buf_);
1400        __f.__f_->destroy();
1401        __f.__f_ = 0;
1402        __f_ = (__base*)&__buf_;
1403        __t->__clone((__base*)&__f.__buf_);
1404        __t->destroy();
1405        __f.__f_ = (__base*)&__f.__buf_;
1406    }
1407    else if (__f_ == (__base*)&__buf_)
1408    {
1409        __f_->__clone((__base*)&__f.__buf_);
1410        __f_->destroy();
1411        __f_ = __f.__f_;
1412        __f.__f_ = (__base*)&__f.__buf_;
1413    }
1414    else if (__f.__f_ == (__base*)&__f.__buf_)
1415    {
1416        __f.__f_->__clone((__base*)&__buf_);
1417        __f.__f_->destroy();
1418        __f.__f_ = __f_;
1419        __f_ = (__base*)&__buf_;
1420    }
1421    else
1422        _VSTD::swap(__f_, __f.__f_);
1423}
1424
1425template<class _Rp, class ..._ArgTypes>
1426_Rp
1427function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
1428{
1429#ifndef _LIBCPP_NO_EXCEPTIONS
1430    if (__f_ == 0)
1431        throw bad_function_call();
1432#endif  // _LIBCPP_NO_EXCEPTIONS
1433    return (*__f_)(_VSTD::forward<_ArgTypes>(__arg)...);
1434}
1435
1436#ifndef _LIBCPP_NO_RTTI
1437
1438template<class _Rp, class ..._ArgTypes>
1439const std::type_info&
1440function<_Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
1441{
1442    if (__f_ == 0)
1443        return typeid(void);
1444    return __f_->target_type();
1445}
1446
1447template<class _Rp, class ..._ArgTypes>
1448template <typename _Tp>
1449_Tp*
1450function<_Rp(_ArgTypes...)>::target() _NOEXCEPT
1451{
1452    if (__f_ == 0)
1453        return (_Tp*)0;
1454    return (_Tp*)__f_->target(typeid(_Tp));
1455}
1456
1457template<class _Rp, class ..._ArgTypes>
1458template <typename _Tp>
1459const _Tp*
1460function<_Rp(_ArgTypes...)>::target() const _NOEXCEPT
1461{
1462    if (__f_ == 0)
1463        return (const _Tp*)0;
1464    return (const _Tp*)__f_->target(typeid(_Tp));
1465}
1466
1467#endif  // _LIBCPP_NO_RTTI
1468
1469template <class _Rp, class... _ArgTypes>
1470inline _LIBCPP_INLINE_VISIBILITY
1471bool
1472operator==(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return !__f;}
1473
1474template <class _Rp, class... _ArgTypes>
1475inline _LIBCPP_INLINE_VISIBILITY
1476bool
1477operator==(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return !__f;}
1478
1479template <class _Rp, class... _ArgTypes>
1480inline _LIBCPP_INLINE_VISIBILITY
1481bool
1482operator!=(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) _NOEXCEPT {return (bool)__f;}
1483
1484template <class _Rp, class... _ArgTypes>
1485inline _LIBCPP_INLINE_VISIBILITY
1486bool
1487operator!=(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) _NOEXCEPT {return (bool)__f;}
1488
1489template <class _Rp, class... _ArgTypes>
1490inline _LIBCPP_INLINE_VISIBILITY
1491void
1492swap(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y) _NOEXCEPT
1493{return __x.swap(__y);}
1494
1495template<class _Tp> struct __is_bind_expression : public false_type {};
1496template<class _Tp> struct _LIBCPP_VISIBLE is_bind_expression
1497    : public __is_bind_expression<typename remove_cv<_Tp>::type> {};
1498
1499template<class _Tp> struct __is_placeholder : public integral_constant<int, 0> {};
1500template<class _Tp> struct _LIBCPP_VISIBLE is_placeholder
1501    : public __is_placeholder<typename remove_cv<_Tp>::type> {};
1502
1503namespace placeholders
1504{
1505
1506template <int _Np> struct __ph {};
1507
1508extern __ph<1>   _1;
1509extern __ph<2>   _2;
1510extern __ph<3>   _3;
1511extern __ph<4>   _4;
1512extern __ph<5>   _5;
1513extern __ph<6>   _6;
1514extern __ph<7>   _7;
1515extern __ph<8>   _8;
1516extern __ph<9>   _9;
1517extern __ph<10> _10;
1518
1519}  // placeholders
1520
1521template<int _Np>
1522struct __is_placeholder<placeholders::__ph<_Np> >
1523    : public integral_constant<int, _Np> {};
1524
1525template <class _Tp, class _Uj>
1526inline _LIBCPP_INLINE_VISIBILITY
1527_Tp&
1528__mu(reference_wrapper<_Tp> __t, _Uj&)
1529{
1530    return __t.get();
1531}
1532
1533template <class _Ti, class ..._Uj, size_t ..._Indx>
1534inline _LIBCPP_INLINE_VISIBILITY
1535typename __invoke_of<_Ti&, _Uj...>::type
1536__mu_expand(_Ti& __ti, tuple<_Uj...>& __uj, __tuple_indices<_Indx...>)
1537{
1538    return __ti(_VSTD::forward<_Uj>(get<_Indx>(__uj))...);
1539}
1540
1541template <class _Ti, class ..._Uj>
1542inline _LIBCPP_INLINE_VISIBILITY
1543typename enable_if
1544<
1545    is_bind_expression<_Ti>::value,
1546    typename __invoke_of<_Ti&, _Uj...>::type
1547>::type
1548__mu(_Ti& __ti, tuple<_Uj...>& __uj)
1549{
1550    typedef typename __make_tuple_indices<sizeof...(_Uj)>::type __indices;
1551    return  __mu_expand(__ti, __uj, __indices());
1552}
1553
1554template <bool IsPh, class _Ti, class _Uj>
1555struct __mu_return2 {};
1556
1557template <class _Ti, class _Uj>
1558struct __mu_return2<true, _Ti, _Uj>
1559{
1560    typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _Uj>::type type;
1561};
1562
1563template <class _Ti, class _Uj>
1564inline _LIBCPP_INLINE_VISIBILITY
1565typename enable_if
1566<
1567    0 < is_placeholder<_Ti>::value,
1568    typename __mu_return2<0 < is_placeholder<_Ti>::value, _Ti, _Uj>::type
1569>::type
1570__mu(_Ti&, _Uj& __uj)
1571{
1572    const size_t _Indx = is_placeholder<_Ti>::value - 1;
1573    return _VSTD::forward<typename tuple_element<_Indx, _Uj>::type>(get<_Indx>(__uj));
1574}
1575
1576template <class _Ti, class _Uj>
1577inline _LIBCPP_INLINE_VISIBILITY
1578typename enable_if
1579<
1580    !is_bind_expression<_Ti>::value &&
1581    is_placeholder<_Ti>::value == 0 &&
1582    !__is_reference_wrapper<_Ti>::value,
1583    _Ti&
1584>::type
1585__mu(_Ti& __ti, _Uj&)
1586{
1587    return __ti;
1588}
1589
1590template <class _Ti, bool IsReferenceWrapper, bool IsBindEx, bool IsPh,
1591          class _TupleUj>
1592struct ____mu_return;
1593
1594template <class _Ti, class ..._Uj>
1595struct ____mu_return<_Ti, false, true, false, tuple<_Uj...> >
1596{
1597    typedef typename __invoke_of<_Ti&, _Uj...>::type type;
1598};
1599
1600template <class _Ti, class _TupleUj>
1601struct ____mu_return<_Ti, false, false, true, _TupleUj>
1602{
1603    typedef typename tuple_element<is_placeholder<_Ti>::value - 1,
1604                                   _TupleUj>::type&& type;
1605};
1606
1607template <class _Ti, class _TupleUj>
1608struct ____mu_return<_Ti, true, false, false, _TupleUj>
1609{
1610    typedef typename _Ti::type& type;
1611};
1612
1613template <class _Ti, class _TupleUj>
1614struct ____mu_return<_Ti, false, false, false, _TupleUj>
1615{
1616    typedef _Ti& type;
1617};
1618
1619template <class _Ti, class _TupleUj>
1620struct __mu_return
1621    : public ____mu_return<_Ti,
1622                           __is_reference_wrapper<_Ti>::value,
1623                           is_bind_expression<_Ti>::value,
1624                           0 < is_placeholder<_Ti>::value,
1625                           _TupleUj>
1626{
1627};
1628
1629template <class _Fp, class _BoundArgs, class _TupleUj>
1630struct __bind_return;
1631
1632template <class _Fp, class ..._BoundArgs, class _TupleUj>
1633struct __bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj>
1634{
1635    typedef typename __invoke_of
1636    <
1637        _Fp&,
1638        typename __mu_return
1639        <
1640            _BoundArgs,
1641            _TupleUj
1642        >::type...
1643    >::type type;
1644};
1645
1646template <class _Fp, class ..._BoundArgs, class _TupleUj>
1647struct __bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj>
1648{
1649    typedef typename __invoke_of
1650    <
1651        _Fp&,
1652        typename __mu_return
1653        <
1654            const _BoundArgs,
1655            _TupleUj
1656        >::type...
1657    >::type type;
1658};
1659
1660template <class _Fp, class _BoundArgs, size_t ..._Indx, class _Args>
1661inline _LIBCPP_INLINE_VISIBILITY
1662typename __bind_return<_Fp, _BoundArgs, _Args>::type
1663__apply_functor(_Fp& __f, _BoundArgs& __bound_args, __tuple_indices<_Indx...>,
1664                _Args&& __args)
1665{
1666    return __invoke(__f, __mu(get<_Indx>(__bound_args), __args)...);
1667}
1668
1669template<class _Fp, class ..._BoundArgs>
1670class __bind
1671    : public __weak_result_type<typename decay<_Fp>::type>
1672{
1673    typedef typename decay<_Fp>::type _Fd;
1674    typedef tuple<typename decay<_BoundArgs>::type...> _Td;
1675    _Fd __f_;
1676    _Td __bound_args_;
1677
1678    typedef typename __make_tuple_indices<sizeof...(_BoundArgs)>::type __indices;
1679public:
1680#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
1681
1682    _LIBCPP_INLINE_VISIBILITY
1683    __bind(const __bind& __b)
1684        : __f_(__b.__f_),
1685          __bound_args_(__b.__bound_args_) {}
1686
1687    _LIBCPP_INLINE_VISIBILITY
1688    __bind& operator=(const __bind& __b)
1689    {
1690        __f_ = __b.__f_;
1691        __bound_args_ = __b.__bound_args_;
1692        return *this;
1693    }
1694
1695    _LIBCPP_INLINE_VISIBILITY
1696    __bind(__bind&& __b)
1697        : __f_(_VSTD::move(__b.__f_)),
1698          __bound_args_(_VSTD::move(__b.__bound_args_)) {}
1699
1700    _LIBCPP_INLINE_VISIBILITY
1701    __bind& operator=(__bind&& __b)
1702    {
1703        __f_ = _VSTD::move(__b.__f_);
1704        __bound_args_ = _VSTD::move(__b.__bound_args_);
1705        return *this;
1706    }
1707
1708#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
1709
1710    template <class _Gp, class ..._BA>
1711      _LIBCPP_INLINE_VISIBILITY
1712      explicit __bind(_Gp&& __f, _BA&& ...__bound_args)
1713        : __f_(_VSTD::forward<_Gp>(__f)),
1714          __bound_args_(_VSTD::forward<_BA>(__bound_args)...) {}
1715
1716    template <class ..._Args>
1717        _LIBCPP_INLINE_VISIBILITY
1718        typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
1719        operator()(_Args&& ...__args)
1720        {
1721            return __apply_functor(__f_, __bound_args_, __indices(),
1722                                  tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
1723        }
1724
1725    template <class ..._Args>
1726        _LIBCPP_INLINE_VISIBILITY
1727        typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
1728        operator()(_Args&& ...__args) const
1729        {
1730            return __apply_functor(__f_, __bound_args_, __indices(),
1731                                   tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
1732        }
1733};
1734
1735template<class _Fp, class ..._BoundArgs>
1736struct __is_bind_expression<__bind<_Fp, _BoundArgs...> > : public true_type {};
1737
1738template<class _Rp, class _Fp, class ..._BoundArgs>
1739class __bind_r
1740    : public __bind<_Fp, _BoundArgs...>
1741{
1742    typedef __bind<_Fp, _BoundArgs...> base;
1743public:
1744    typedef _Rp result_type;
1745
1746#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
1747
1748    _LIBCPP_INLINE_VISIBILITY
1749    __bind_r(const __bind_r& __b)
1750        : base(_VSTD::forward<const base&>(__b)) {}
1751
1752    _LIBCPP_INLINE_VISIBILITY
1753    __bind_r& operator=(const __bind_r& __b)
1754    {
1755        base::operator=(_VSTD::forward<const base&>(__b));
1756        return *this;
1757    }
1758
1759    _LIBCPP_INLINE_VISIBILITY
1760    __bind_r(__bind_r&& __b)
1761        : base(_VSTD::forward<base>(__b)) {}
1762
1763    _LIBCPP_INLINE_VISIBILITY
1764    __bind_r& operator=(__bind_r&& __b)
1765    {
1766        base::operator=(_VSTD::forward<base>(__b));
1767        return *this;
1768    }
1769
1770#endif  // _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
1771
1772    template <class _Gp, class ..._BA>
1773      _LIBCPP_INLINE_VISIBILITY
1774      explicit __bind_r(_Gp&& __f, _BA&& ...__bound_args)
1775        : base(_VSTD::forward<_Gp>(__f),
1776               _VSTD::forward<_BA>(__bound_args)...) {}
1777
1778    template <class ..._Args>
1779        _LIBCPP_INLINE_VISIBILITY
1780        result_type
1781        operator()(_Args&& ...__args)
1782        {
1783            return base::operator()(_VSTD::forward<_Args>(__args)...);
1784        }
1785
1786    template <class ..._Args>
1787        _LIBCPP_INLINE_VISIBILITY
1788        result_type
1789        operator()(_Args&& ...__args) const
1790        {
1791            return base::operator()(_VSTD::forward<_Args>(__args)...);
1792        }
1793};
1794
1795template<class _Rp, class _Fp, class ..._BoundArgs>
1796struct __is_bind_expression<__bind_r<_Rp, _Fp, _BoundArgs...> > : public true_type {};
1797
1798template<class _Fp, class ..._BoundArgs>
1799inline _LIBCPP_INLINE_VISIBILITY
1800__bind<_Fp, _BoundArgs...>
1801bind(_Fp&& __f, _BoundArgs&&... __bound_args)
1802{
1803    typedef __bind<_Fp, _BoundArgs...> type;
1804    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
1805}
1806
1807template<class _Rp, class _Fp, class ..._BoundArgs>
1808inline _LIBCPP_INLINE_VISIBILITY
1809__bind_r<_Rp, _Fp, _BoundArgs...>
1810bind(_Fp&& __f, _BoundArgs&&... __bound_args)
1811{
1812    typedef __bind_r<_Rp, _Fp, _BoundArgs...> type;
1813    return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
1814}
1815
1816#endif  // _LIBCPP_HAS_NO_VARIADICS
1817
1818template <>
1819struct _LIBCPP_VISIBLE hash<bool>
1820    : public unary_function<bool, size_t>
1821{
1822    _LIBCPP_INLINE_VISIBILITY
1823    size_t operator()(bool __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1824};
1825
1826template <>
1827struct _LIBCPP_VISIBLE hash<char>
1828    : public unary_function<char, size_t>
1829{
1830    _LIBCPP_INLINE_VISIBILITY
1831    size_t operator()(char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1832};
1833
1834template <>
1835struct _LIBCPP_VISIBLE hash<signed char>
1836    : public unary_function<signed char, size_t>
1837{
1838    _LIBCPP_INLINE_VISIBILITY
1839    size_t operator()(signed char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1840};
1841
1842template <>
1843struct _LIBCPP_VISIBLE hash<unsigned char>
1844    : public unary_function<unsigned char, size_t>
1845{
1846    _LIBCPP_INLINE_VISIBILITY
1847    size_t operator()(unsigned char __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1848};
1849
1850#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
1851
1852template <>
1853struct _LIBCPP_VISIBLE hash<char16_t>
1854    : public unary_function<char16_t, size_t>
1855{
1856    _LIBCPP_INLINE_VISIBILITY
1857    size_t operator()(char16_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1858};
1859
1860template <>
1861struct _LIBCPP_VISIBLE hash<char32_t>
1862    : public unary_function<char32_t, size_t>
1863{
1864    _LIBCPP_INLINE_VISIBILITY
1865    size_t operator()(char32_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1866};
1867
1868#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
1869
1870template <>
1871struct _LIBCPP_VISIBLE hash<wchar_t>
1872    : public unary_function<wchar_t, size_t>
1873{
1874    _LIBCPP_INLINE_VISIBILITY
1875    size_t operator()(wchar_t __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1876};
1877
1878template <>
1879struct _LIBCPP_VISIBLE hash<short>
1880    : public unary_function<short, size_t>
1881{
1882    _LIBCPP_INLINE_VISIBILITY
1883    size_t operator()(short __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1884};
1885
1886template <>
1887struct _LIBCPP_VISIBLE hash<unsigned short>
1888    : public unary_function<unsigned short, size_t>
1889{
1890    _LIBCPP_INLINE_VISIBILITY
1891    size_t operator()(unsigned short __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1892};
1893
1894template <>
1895struct _LIBCPP_VISIBLE hash<int>
1896    : public unary_function<int, size_t>
1897{
1898    _LIBCPP_INLINE_VISIBILITY
1899    size_t operator()(int __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1900};
1901
1902template <>
1903struct _LIBCPP_VISIBLE hash<unsigned int>
1904    : public unary_function<unsigned int, size_t>
1905{
1906    _LIBCPP_INLINE_VISIBILITY
1907    size_t operator()(unsigned int __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1908};
1909
1910template <>
1911struct _LIBCPP_VISIBLE hash<long>
1912    : public unary_function<long, size_t>
1913{
1914    _LIBCPP_INLINE_VISIBILITY
1915    size_t operator()(long __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1916};
1917
1918template <>
1919struct _LIBCPP_VISIBLE hash<unsigned long>
1920    : public unary_function<unsigned long, size_t>
1921{
1922    _LIBCPP_INLINE_VISIBILITY
1923    size_t operator()(unsigned long __v) const _NOEXCEPT {return static_cast<size_t>(__v);}
1924};
1925
1926template <>
1927struct _LIBCPP_VISIBLE hash<long long>
1928    : public __scalar_hash<long long>
1929{
1930};
1931
1932template <>
1933struct _LIBCPP_VISIBLE hash<unsigned long long>
1934    : public __scalar_hash<unsigned long long>
1935{
1936};
1937
1938template <>
1939struct _LIBCPP_VISIBLE hash<float>
1940    : public __scalar_hash<float>
1941{
1942    _LIBCPP_INLINE_VISIBILITY
1943    size_t operator()(float __v) const _NOEXCEPT
1944    {
1945        // -0.0 and 0.0 should return same hash
1946       if (__v == 0)
1947           return 0;
1948        return __scalar_hash<float>::operator()(__v);
1949    }
1950};
1951
1952template <>
1953struct _LIBCPP_VISIBLE hash<double>
1954    : public __scalar_hash<double>
1955{
1956    _LIBCPP_INLINE_VISIBILITY
1957    size_t operator()(double __v) const _NOEXCEPT
1958    {
1959        // -0.0 and 0.0 should return same hash
1960       if (__v == 0)
1961           return 0;
1962        return __scalar_hash<double>::operator()(__v);
1963    }
1964};
1965
1966template <>
1967struct _LIBCPP_VISIBLE hash<long double>
1968    : public __scalar_hash<long double>
1969{
1970    _LIBCPP_INLINE_VISIBILITY
1971    size_t operator()(long double __v) const _NOEXCEPT
1972    {
1973        // -0.0 and 0.0 should return same hash
1974        if (__v == 0)
1975            return 0;
1976#if defined(__i386__)
1977        // Zero out padding bits
1978        union
1979        {
1980            long double __t;
1981            struct
1982            {
1983                size_t __a;
1984                size_t __b;
1985                size_t __c;
1986                size_t __d;
1987            };
1988        } __u;
1989        __u.__a = 0;
1990        __u.__b = 0;
1991        __u.__c = 0;
1992        __u.__d = 0;
1993        __u.__t = __v;
1994        return __u.__a ^ __u.__b ^ __u.__c ^ __u.__d;
1995#elif defined(__x86_64__)
1996        // Zero out padding bits
1997        union
1998        {
1999            long double __t;
2000            struct
2001            {
2002                size_t __a;
2003                size_t __b;
2004            };
2005        } __u;
2006        __u.__a = 0;
2007        __u.__b = 0;
2008        __u.__t = __v;
2009        return __u.__a ^ __u.__b;
2010#else
2011        return __scalar_hash<long double>::operator()(__v);
2012#endif
2013    }
2014};
2015
2016// struct hash<T*> in <memory>
2017
2018_LIBCPP_END_NAMESPACE_STD
2019
2020#endif  // _LIBCPP_FUNCTIONAL
2021