libstdc++
functional
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1 // <functional> -*- C++ -*-
2 
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 // 2011 Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20 
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25 
26 /*
27  * Copyright (c) 1997
28  * Silicon Graphics Computer Systems, Inc.
29  *
30  * Permission to use, copy, modify, distribute and sell this software
31  * and its documentation for any purpose is hereby granted without fee,
32  * provided that the above copyright notice appear in all copies and
33  * that both that copyright notice and this permission notice appear
34  * in supporting documentation. Silicon Graphics makes no
35  * representations about the suitability of this software for any
36  * purpose. It is provided "as is" without express or implied warranty.
37  *
38  */
39 
40 /** @file include/functional
41  * This is a Standard C++ Library header.
42  */
43 
44 #ifndef _GLIBCXX_FUNCTIONAL
45 #define _GLIBCXX_FUNCTIONAL 1
46 
47 #pragma GCC system_header
48 
49 #include <bits/c++config.h>
50 #include <bits/stl_function.h>
51 
52 #ifdef __GXX_EXPERIMENTAL_CXX0X__
53 
54 #include <typeinfo>
55 #include <new>
56 #include <tuple>
57 #include <type_traits>
58 #include <bits/functexcept.h>
59 #include <bits/functional_hash.h>
60 
61 namespace std _GLIBCXX_VISIBILITY(default)
62 {
63 _GLIBCXX_BEGIN_NAMESPACE_VERSION
64 
65  template<typename _MemberPointer>
66  class _Mem_fn;
67  template<typename _Tp, typename _Class>
68  _Mem_fn<_Tp _Class::*>
69  mem_fn(_Tp _Class::*);
70 
71 _GLIBCXX_HAS_NESTED_TYPE(result_type)
72 
73  /// If we have found a result_type, extract it.
74  template<bool _Has_result_type, typename _Functor>
76  { };
77 
78  template<typename _Functor>
79  struct _Maybe_get_result_type<true, _Functor>
80  { typedef typename _Functor::result_type result_type; };
81 
82  /**
83  * Base class for any function object that has a weak result type, as
84  * defined in 3.3/3 of TR1.
85  */
86  template<typename _Functor>
88  : _Maybe_get_result_type<__has_result_type<_Functor>::value, _Functor>
89  { };
90 
91  /// Retrieve the result type for a function type.
92  template<typename _Res, typename... _ArgTypes>
93  struct _Weak_result_type_impl<_Res(_ArgTypes...)>
94  { typedef _Res result_type; };
95 
96  template<typename _Res, typename... _ArgTypes>
97  struct _Weak_result_type_impl<_Res(_ArgTypes......)>
98  { typedef _Res result_type; };
99 
100  template<typename _Res, typename... _ArgTypes>
101  struct _Weak_result_type_impl<_Res(_ArgTypes...) const>
102  { typedef _Res result_type; };
103 
104  template<typename _Res, typename... _ArgTypes>
105  struct _Weak_result_type_impl<_Res(_ArgTypes......) const>
106  { typedef _Res result_type; };
107 
108  template<typename _Res, typename... _ArgTypes>
109  struct _Weak_result_type_impl<_Res(_ArgTypes...) volatile>
110  { typedef _Res result_type; };
111 
112  template<typename _Res, typename... _ArgTypes>
113  struct _Weak_result_type_impl<_Res(_ArgTypes......) volatile>
114  { typedef _Res result_type; };
115 
116  template<typename _Res, typename... _ArgTypes>
117  struct _Weak_result_type_impl<_Res(_ArgTypes...) const volatile>
118  { typedef _Res result_type; };
119 
120  template<typename _Res, typename... _ArgTypes>
121  struct _Weak_result_type_impl<_Res(_ArgTypes......) const volatile>
122  { typedef _Res result_type; };
123 
124  /// Retrieve the result type for a function reference.
125  template<typename _Res, typename... _ArgTypes>
126  struct _Weak_result_type_impl<_Res(&)(_ArgTypes...)>
127  { typedef _Res result_type; };
128 
129  template<typename _Res, typename... _ArgTypes>
130  struct _Weak_result_type_impl<_Res(&)(_ArgTypes......)>
131  { typedef _Res result_type; };
132 
133  /// Retrieve the result type for a function pointer.
134  template<typename _Res, typename... _ArgTypes>
135  struct _Weak_result_type_impl<_Res(*)(_ArgTypes...)>
136  { typedef _Res result_type; };
137 
138  template<typename _Res, typename... _ArgTypes>
139  struct _Weak_result_type_impl<_Res(*)(_ArgTypes......)>
140  { typedef _Res result_type; };
141 
142  /// Retrieve result type for a member function pointer.
143  template<typename _Res, typename _Class, typename... _ArgTypes>
144  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)>
145  { typedef _Res result_type; };
146 
147  template<typename _Res, typename _Class, typename... _ArgTypes>
148  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)>
149  { typedef _Res result_type; };
150 
151  /// Retrieve result type for a const member function pointer.
152  template<typename _Res, typename _Class, typename... _ArgTypes>
153  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) const>
154  { typedef _Res result_type; };
155 
156  template<typename _Res, typename _Class, typename... _ArgTypes>
157  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) const>
158  { typedef _Res result_type; };
159 
160  /// Retrieve result type for a volatile member function pointer.
161  template<typename _Res, typename _Class, typename... _ArgTypes>
162  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) volatile>
163  { typedef _Res result_type; };
164 
165  template<typename _Res, typename _Class, typename... _ArgTypes>
166  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) volatile>
167  { typedef _Res result_type; };
168 
169  /// Retrieve result type for a const volatile member function pointer.
170  template<typename _Res, typename _Class, typename... _ArgTypes>
171  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)
172  const volatile>
173  { typedef _Res result_type; };
174 
175  template<typename _Res, typename _Class, typename... _ArgTypes>
176  struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)
177  const volatile>
178  { typedef _Res result_type; };
179 
180  /**
181  * Strip top-level cv-qualifiers from the function object and let
182  * _Weak_result_type_impl perform the real work.
183  */
184  template<typename _Functor>
186  : _Weak_result_type_impl<typename remove_cv<_Functor>::type>
187  { };
188 
189  /// Determines if the type _Tp derives from unary_function.
190  template<typename _Tp>
191  struct _Derives_from_unary_function : __sfinae_types
192  {
193  private:
194  template<typename _T1, typename _Res>
195  static __one __test(const volatile unary_function<_T1, _Res>*);
196 
197  // It's tempting to change "..." to const volatile void*, but
198  // that fails when _Tp is a function type.
199  static __two __test(...);
200 
201  public:
202  static const bool value = sizeof(__test((_Tp*)0)) == 1;
203  };
204 
205  /// Determines if the type _Tp derives from binary_function.
206  template<typename _Tp>
207  struct _Derives_from_binary_function : __sfinae_types
208  {
209  private:
210  template<typename _T1, typename _T2, typename _Res>
211  static __one __test(const volatile binary_function<_T1, _T2, _Res>*);
212 
213  // It's tempting to change "..." to const volatile void*, but
214  // that fails when _Tp is a function type.
215  static __two __test(...);
216 
217  public:
218  static const bool value = sizeof(__test((_Tp*)0)) == 1;
219  };
220 
221  /**
222  * Invoke a function object, which may be either a member pointer or a
223  * function object. The first parameter will tell which.
224  */
225  template<typename _Functor, typename... _Args>
226  inline
227  typename enable_if<
231  typename result_of<_Functor(_Args&&...)>::type
232  >::type
233  __invoke(_Functor& __f, _Args&&... __args)
234  {
235  return __f(std::forward<_Args>(__args)...);
236  }
237 
238  template<typename _Functor, typename... _Args>
239  inline
240  typename enable_if<
241  (is_member_pointer<_Functor>::value
242  && !is_function<_Functor>::value
243  && !is_function<typename remove_pointer<_Functor>::type>::value),
244  typename result_of<_Functor(_Args&&...)>::type
245  >::type
246  __invoke(_Functor& __f, _Args&&... __args)
247  {
248  return mem_fn(__f)(std::forward<_Args>(__args)...);
249  }
250 
251  // To pick up function references (that will become function pointers)
252  template<typename _Functor, typename... _Args>
253  inline
254  typename enable_if<
255  (is_pointer<_Functor>::value
256  && is_function<typename remove_pointer<_Functor>::type>::value),
257  typename result_of<_Functor(_Args&&...)>::type
258  >::type
259  __invoke(_Functor __f, _Args&&... __args)
260  {
261  return __f(std::forward<_Args>(__args)...);
262  }
263 
264  /**
265  * Knowing which of unary_function and binary_function _Tp derives
266  * from, derives from the same and ensures that reference_wrapper
267  * will have a weak result type. See cases below.
268  */
269  template<bool _Unary, bool _Binary, typename _Tp>
270  struct _Reference_wrapper_base_impl;
271 
272  // None of the nested argument types.
273  template<typename _Tp>
274  struct _Reference_wrapper_base_impl<false, false, _Tp>
275  : _Weak_result_type<_Tp>
276  { };
277 
278  // Nested argument_type only.
279  template<typename _Tp>
280  struct _Reference_wrapper_base_impl<true, false, _Tp>
281  : _Weak_result_type<_Tp>
282  {
283  typedef typename _Tp::argument_type argument_type;
284  };
285 
286  // Nested first_argument_type and second_argument_type only.
287  template<typename _Tp>
288  struct _Reference_wrapper_base_impl<false, true, _Tp>
289  : _Weak_result_type<_Tp>
290  {
291  typedef typename _Tp::first_argument_type first_argument_type;
292  typedef typename _Tp::second_argument_type second_argument_type;
293  };
294 
295  // All the nested argument types.
296  template<typename _Tp>
297  struct _Reference_wrapper_base_impl<true, true, _Tp>
298  : _Weak_result_type<_Tp>
299  {
300  typedef typename _Tp::argument_type argument_type;
301  typedef typename _Tp::first_argument_type first_argument_type;
302  typedef typename _Tp::second_argument_type second_argument_type;
303  };
304 
305  _GLIBCXX_HAS_NESTED_TYPE(argument_type)
306  _GLIBCXX_HAS_NESTED_TYPE(first_argument_type)
307  _GLIBCXX_HAS_NESTED_TYPE(second_argument_type)
308 
309  /**
310  * Derives from unary_function or binary_function when it
311  * can. Specializations handle all of the easy cases. The primary
312  * template determines what to do with a class type, which may
313  * derive from both unary_function and binary_function.
314  */
315  template<typename _Tp>
317  : _Reference_wrapper_base_impl<
318  __has_argument_type<_Tp>::value,
319  __has_first_argument_type<_Tp>::value
320  && __has_second_argument_type<_Tp>::value,
321  _Tp>
322  { };
323 
324  // - a function type (unary)
325  template<typename _Res, typename _T1>
326  struct _Reference_wrapper_base<_Res(_T1)>
327  : unary_function<_T1, _Res>
328  { };
329 
330  template<typename _Res, typename _T1>
331  struct _Reference_wrapper_base<_Res(_T1) const>
332  : unary_function<_T1, _Res>
333  { };
334 
335  template<typename _Res, typename _T1>
336  struct _Reference_wrapper_base<_Res(_T1) volatile>
337  : unary_function<_T1, _Res>
338  { };
339 
340  template<typename _Res, typename _T1>
341  struct _Reference_wrapper_base<_Res(_T1) const volatile>
342  : unary_function<_T1, _Res>
343  { };
344 
345  // - a function type (binary)
346  template<typename _Res, typename _T1, typename _T2>
347  struct _Reference_wrapper_base<_Res(_T1, _T2)>
348  : binary_function<_T1, _T2, _Res>
349  { };
350 
351  template<typename _Res, typename _T1, typename _T2>
352  struct _Reference_wrapper_base<_Res(_T1, _T2) const>
353  : binary_function<_T1, _T2, _Res>
354  { };
355 
356  template<typename _Res, typename _T1, typename _T2>
357  struct _Reference_wrapper_base<_Res(_T1, _T2) volatile>
358  : binary_function<_T1, _T2, _Res>
359  { };
360 
361  template<typename _Res, typename _T1, typename _T2>
362  struct _Reference_wrapper_base<_Res(_T1, _T2) const volatile>
363  : binary_function<_T1, _T2, _Res>
364  { };
365 
366  // - a function pointer type (unary)
367  template<typename _Res, typename _T1>
368  struct _Reference_wrapper_base<_Res(*)(_T1)>
369  : unary_function<_T1, _Res>
370  { };
371 
372  // - a function pointer type (binary)
373  template<typename _Res, typename _T1, typename _T2>
374  struct _Reference_wrapper_base<_Res(*)(_T1, _T2)>
375  : binary_function<_T1, _T2, _Res>
376  { };
377 
378  // - a pointer to member function type (unary, no qualifiers)
379  template<typename _Res, typename _T1>
380  struct _Reference_wrapper_base<_Res (_T1::*)()>
381  : unary_function<_T1*, _Res>
382  { };
383 
384  // - a pointer to member function type (binary, no qualifiers)
385  template<typename _Res, typename _T1, typename _T2>
386  struct _Reference_wrapper_base<_Res (_T1::*)(_T2)>
387  : binary_function<_T1*, _T2, _Res>
388  { };
389 
390  // - a pointer to member function type (unary, const)
391  template<typename _Res, typename _T1>
392  struct _Reference_wrapper_base<_Res (_T1::*)() const>
393  : unary_function<const _T1*, _Res>
394  { };
395 
396  // - a pointer to member function type (binary, const)
397  template<typename _Res, typename _T1, typename _T2>
398  struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const>
399  : binary_function<const _T1*, _T2, _Res>
400  { };
401 
402  // - a pointer to member function type (unary, volatile)
403  template<typename _Res, typename _T1>
404  struct _Reference_wrapper_base<_Res (_T1::*)() volatile>
405  : unary_function<volatile _T1*, _Res>
406  { };
407 
408  // - a pointer to member function type (binary, volatile)
409  template<typename _Res, typename _T1, typename _T2>
410  struct _Reference_wrapper_base<_Res (_T1::*)(_T2) volatile>
411  : binary_function<volatile _T1*, _T2, _Res>
412  { };
413 
414  // - a pointer to member function type (unary, const volatile)
415  template<typename _Res, typename _T1>
416  struct _Reference_wrapper_base<_Res (_T1::*)() const volatile>
417  : unary_function<const volatile _T1*, _Res>
418  { };
419 
420  // - a pointer to member function type (binary, const volatile)
421  template<typename _Res, typename _T1, typename _T2>
422  struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const volatile>
423  : binary_function<const volatile _T1*, _T2, _Res>
424  { };
425 
426  /**
427  * @brief Primary class template for reference_wrapper.
428  * @ingroup functors
429  * @{
430  */
431  template<typename _Tp>
433  : public _Reference_wrapper_base<typename remove_cv<_Tp>::type>
434  {
435  _Tp* _M_data;
436 
437  public:
438  typedef _Tp type;
439 
440  reference_wrapper(_Tp& __indata) noexcept
441  : _M_data(std::__addressof(__indata))
442  { }
443 
444  reference_wrapper(_Tp&&) = delete;
445 
446  reference_wrapper(const reference_wrapper<_Tp>& __inref) noexcept
447  : _M_data(__inref._M_data)
448  { }
449 
451  operator=(const reference_wrapper<_Tp>& __inref) noexcept
452  {
453  _M_data = __inref._M_data;
454  return *this;
455  }
456 
457  operator _Tp&() const noexcept
458  { return this->get(); }
459 
460  _Tp&
461  get() const noexcept
462  { return *_M_data; }
463 
464  template<typename... _Args>
465  typename result_of<_Tp&(_Args&&...)>::type
466  operator()(_Args&&... __args) const
467  {
468  return __invoke(get(), std::forward<_Args>(__args)...);
469  }
470  };
471 
472 
473  /// Denotes a reference should be taken to a variable.
474  template<typename _Tp>
476  ref(_Tp& __t) noexcept
477  { return reference_wrapper<_Tp>(__t); }
478 
479  /// Denotes a const reference should be taken to a variable.
480  template<typename _Tp>
481  inline reference_wrapper<const _Tp>
482  cref(const _Tp& __t) noexcept
483  { return reference_wrapper<const _Tp>(__t); }
484 
485  template<typename _Tp>
486  void ref(const _Tp&&) = delete;
487 
488  template<typename _Tp>
489  void cref(const _Tp&&) = delete;
490 
491  /// Partial specialization.
492  template<typename _Tp>
493  inline reference_wrapper<_Tp>
495  { return ref(__t.get()); }
496 
497  /// Partial specialization.
498  template<typename _Tp>
499  inline reference_wrapper<const _Tp>
501  { return cref(__t.get()); }
502 
503  // @} group functors
504 
505  /**
506  * Derives from @c unary_function or @c binary_function, or perhaps
507  * nothing, depending on the number of arguments provided. The
508  * primary template is the basis case, which derives nothing.
509  */
510  template<typename _Res, typename... _ArgTypes>
512 
513  /// Derives from @c unary_function, as appropriate.
514  template<typename _Res, typename _T1>
516  : std::unary_function<_T1, _Res> { };
517 
518  /// Derives from @c binary_function, as appropriate.
519  template<typename _Res, typename _T1, typename _T2>
520  struct _Maybe_unary_or_binary_function<_Res, _T1, _T2>
521  : std::binary_function<_T1, _T2, _Res> { };
522 
523  /// Implementation of @c mem_fn for member function pointers.
524  template<typename _Res, typename _Class, typename... _ArgTypes>
525  class _Mem_fn<_Res (_Class::*)(_ArgTypes...)>
526  : public _Maybe_unary_or_binary_function<_Res, _Class*, _ArgTypes...>
527  {
528  typedef _Res (_Class::*_Functor)(_ArgTypes...);
529 
530  template<typename _Tp>
531  _Res
532  _M_call(_Tp& __object, const volatile _Class *,
533  _ArgTypes... __args) const
534  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
535 
536  template<typename _Tp>
537  _Res
538  _M_call(_Tp& __ptr, const volatile void *, _ArgTypes... __args) const
539  { return ((*__ptr).*__pmf)(std::forward<_ArgTypes>(__args)...); }
540 
541  public:
542  typedef _Res result_type;
543 
544  explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
545 
546  // Handle objects
547  _Res
548  operator()(_Class& __object, _ArgTypes... __args) const
549  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
550 
551  // Handle pointers
552  _Res
553  operator()(_Class* __object, _ArgTypes... __args) const
554  { return (__object->*__pmf)(std::forward<_ArgTypes>(__args)...); }
555 
556  // Handle smart pointers, references and pointers to derived
557  template<typename _Tp>
558  _Res
559  operator()(_Tp& __object, _ArgTypes... __args) const
560  {
561  return _M_call(__object, &__object,
562  std::forward<_ArgTypes>(__args)...);
563  }
564 
565  private:
566  _Functor __pmf;
567  };
568 
569  /// Implementation of @c mem_fn for const member function pointers.
570  template<typename _Res, typename _Class, typename... _ArgTypes>
571  class _Mem_fn<_Res (_Class::*)(_ArgTypes...) const>
572  : public _Maybe_unary_or_binary_function<_Res, const _Class*,
573  _ArgTypes...>
574  {
575  typedef _Res (_Class::*_Functor)(_ArgTypes...) const;
576 
577  template<typename _Tp>
578  _Res
579  _M_call(_Tp& __object, const volatile _Class *,
580  _ArgTypes... __args) const
581  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
582 
583  template<typename _Tp>
584  _Res
585  _M_call(_Tp& __ptr, const volatile void *, _ArgTypes... __args) const
586  { return ((*__ptr).*__pmf)(std::forward<_ArgTypes>(__args)...); }
587 
588  public:
589  typedef _Res result_type;
590 
591  explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
592 
593  // Handle objects
594  _Res
595  operator()(const _Class& __object, _ArgTypes... __args) const
596  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
597 
598  // Handle pointers
599  _Res
600  operator()(const _Class* __object, _ArgTypes... __args) const
601  { return (__object->*__pmf)(std::forward<_ArgTypes>(__args)...); }
602 
603  // Handle smart pointers, references and pointers to derived
604  template<typename _Tp>
605  _Res operator()(_Tp& __object, _ArgTypes... __args) const
606  {
607  return _M_call(__object, &__object,
608  std::forward<_ArgTypes>(__args)...);
609  }
610 
611  private:
612  _Functor __pmf;
613  };
614 
615  /// Implementation of @c mem_fn for volatile member function pointers.
616  template<typename _Res, typename _Class, typename... _ArgTypes>
617  class _Mem_fn<_Res (_Class::*)(_ArgTypes...) volatile>
618  : public _Maybe_unary_or_binary_function<_Res, volatile _Class*,
619  _ArgTypes...>
620  {
621  typedef _Res (_Class::*_Functor)(_ArgTypes...) volatile;
622 
623  template<typename _Tp>
624  _Res
625  _M_call(_Tp& __object, const volatile _Class *,
626  _ArgTypes... __args) const
627  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
628 
629  template<typename _Tp>
630  _Res
631  _M_call(_Tp& __ptr, const volatile void *, _ArgTypes... __args) const
632  { return ((*__ptr).*__pmf)(std::forward<_ArgTypes>(__args)...); }
633 
634  public:
635  typedef _Res result_type;
636 
637  explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
638 
639  // Handle objects
640  _Res
641  operator()(volatile _Class& __object, _ArgTypes... __args) const
642  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
643 
644  // Handle pointers
645  _Res
646  operator()(volatile _Class* __object, _ArgTypes... __args) const
647  { return (__object->*__pmf)(std::forward<_ArgTypes>(__args)...); }
648 
649  // Handle smart pointers, references and pointers to derived
650  template<typename _Tp>
651  _Res
652  operator()(_Tp& __object, _ArgTypes... __args) const
653  {
654  return _M_call(__object, &__object,
655  std::forward<_ArgTypes>(__args)...);
656  }
657 
658  private:
659  _Functor __pmf;
660  };
661 
662  /// Implementation of @c mem_fn for const volatile member function pointers.
663  template<typename _Res, typename _Class, typename... _ArgTypes>
664  class _Mem_fn<_Res (_Class::*)(_ArgTypes...) const volatile>
665  : public _Maybe_unary_or_binary_function<_Res, const volatile _Class*,
666  _ArgTypes...>
667  {
668  typedef _Res (_Class::*_Functor)(_ArgTypes...) const volatile;
669 
670  template<typename _Tp>
671  _Res
672  _M_call(_Tp& __object, const volatile _Class *,
673  _ArgTypes... __args) const
674  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
675 
676  template<typename _Tp>
677  _Res
678  _M_call(_Tp& __ptr, const volatile void *, _ArgTypes... __args) const
679  { return ((*__ptr).*__pmf)(std::forward<_ArgTypes>(__args)...); }
680 
681  public:
682  typedef _Res result_type;
683 
684  explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
685 
686  // Handle objects
687  _Res
688  operator()(const volatile _Class& __object, _ArgTypes... __args) const
689  { return (__object.*__pmf)(std::forward<_ArgTypes>(__args)...); }
690 
691  // Handle pointers
692  _Res
693  operator()(const volatile _Class* __object, _ArgTypes... __args) const
694  { return (__object->*__pmf)(std::forward<_ArgTypes>(__args)...); }
695 
696  // Handle smart pointers, references and pointers to derived
697  template<typename _Tp>
698  _Res operator()(_Tp& __object, _ArgTypes... __args) const
699  {
700  return _M_call(__object, &__object,
701  std::forward<_ArgTypes>(__args)...);
702  }
703 
704  private:
705  _Functor __pmf;
706  };
707 
708 
709  template<typename _Tp, bool>
710  struct _Mem_fn_const_or_non
711  {
712  typedef const _Tp& type;
713  };
714 
715  template<typename _Tp>
716  struct _Mem_fn_const_or_non<_Tp, false>
717  {
718  typedef _Tp& type;
719  };
720 
721  template<typename _Res, typename _Class>
722  class _Mem_fn<_Res _Class::*>
723  {
724  // This bit of genius is due to Peter Dimov, improved slightly by
725  // Douglas Gregor.
726  template<typename _Tp>
727  _Res&
728  _M_call(_Tp& __object, _Class *) const
729  { return __object.*__pm; }
730 
731  template<typename _Tp, typename _Up>
732  _Res&
733  _M_call(_Tp& __object, _Up * const *) const
734  { return (*__object).*__pm; }
735 
736  template<typename _Tp, typename _Up>
737  const _Res&
738  _M_call(_Tp& __object, const _Up * const *) const
739  { return (*__object).*__pm; }
740 
741  template<typename _Tp>
742  const _Res&
743  _M_call(_Tp& __object, const _Class *) const
744  { return __object.*__pm; }
745 
746  template<typename _Tp>
747  const _Res&
748  _M_call(_Tp& __ptr, const volatile void*) const
749  { return (*__ptr).*__pm; }
750 
751  template<typename _Tp> static _Tp& __get_ref();
752 
753  template<typename _Tp>
754  static __sfinae_types::__one __check_const(_Tp&, _Class*);
755  template<typename _Tp, typename _Up>
756  static __sfinae_types::__one __check_const(_Tp&, _Up * const *);
757  template<typename _Tp, typename _Up>
758  static __sfinae_types::__two __check_const(_Tp&, const _Up * const *);
759  template<typename _Tp>
760  static __sfinae_types::__two __check_const(_Tp&, const _Class*);
761  template<typename _Tp>
762  static __sfinae_types::__two __check_const(_Tp&, const volatile void*);
763 
764  public:
765  template<typename _Tp>
766  struct _Result_type
767  : _Mem_fn_const_or_non<_Res,
768  (sizeof(__sfinae_types::__two)
769  == sizeof(__check_const<_Tp>(__get_ref<_Tp>(), (_Tp*)0)))>
770  { };
771 
772  template<typename _Signature>
773  struct result;
774 
775  template<typename _CVMem, typename _Tp>
776  struct result<_CVMem(_Tp)>
777  : public _Result_type<_Tp> { };
778 
779  template<typename _CVMem, typename _Tp>
780  struct result<_CVMem(_Tp&)>
781  : public _Result_type<_Tp> { };
782 
783  explicit
784  _Mem_fn(_Res _Class::*__pm) : __pm(__pm) { }
785 
786  // Handle objects
787  _Res&
788  operator()(_Class& __object) const
789  { return __object.*__pm; }
790 
791  const _Res&
792  operator()(const _Class& __object) const
793  { return __object.*__pm; }
794 
795  // Handle pointers
796  _Res&
797  operator()(_Class* __object) const
798  { return __object->*__pm; }
799 
800  const _Res&
801  operator()(const _Class* __object) const
802  { return __object->*__pm; }
803 
804  // Handle smart pointers and derived
805  template<typename _Tp>
806  typename _Result_type<_Tp>::type
807  operator()(_Tp& __unknown) const
808  { return _M_call(__unknown, &__unknown); }
809 
810  private:
811  _Res _Class::*__pm;
812  };
813 
814  /**
815  * @brief Returns a function object that forwards to the member
816  * pointer @a pm.
817  * @ingroup functors
818  */
819  template<typename _Tp, typename _Class>
820  inline _Mem_fn<_Tp _Class::*>
821  mem_fn(_Tp _Class::* __pm)
822  {
823  return _Mem_fn<_Tp _Class::*>(__pm);
824  }
825 
826  /**
827  * @brief Determines if the given type _Tp is a function object
828  * should be treated as a subexpression when evaluating calls to
829  * function objects returned by bind(). [TR1 3.6.1]
830  * @ingroup binders
831  */
832  template<typename _Tp>
834  : public false_type { };
835 
836  /**
837  * @brief Determines if the given type _Tp is a placeholder in a
838  * bind() expression and, if so, which placeholder it is. [TR1 3.6.2]
839  * @ingroup binders
840  */
841  template<typename _Tp>
843  : public integral_constant<int, 0>
844  { };
845 
846  /** @brief The type of placeholder objects defined by libstdc++.
847  * @ingroup binders
848  */
849  template<int _Num> struct _Placeholder { };
850 
851  _GLIBCXX_END_NAMESPACE_VERSION
852 
853  /** @namespace std::placeholders
854  * @brief ISO C++11 entities sub-namespace for functional.
855  * @ingroup binders
856  */
857  namespace placeholders
858  {
859  _GLIBCXX_BEGIN_NAMESPACE_VERSION
860  /* Define a large number of placeholders. There is no way to
861  * simplify this with variadic templates, because we're introducing
862  * unique names for each.
863  */
864  extern const _Placeholder<1> _1;
865  extern const _Placeholder<2> _2;
866  extern const _Placeholder<3> _3;
867  extern const _Placeholder<4> _4;
868  extern const _Placeholder<5> _5;
869  extern const _Placeholder<6> _6;
870  extern const _Placeholder<7> _7;
871  extern const _Placeholder<8> _8;
872  extern const _Placeholder<9> _9;
873  extern const _Placeholder<10> _10;
874  extern const _Placeholder<11> _11;
875  extern const _Placeholder<12> _12;
876  extern const _Placeholder<13> _13;
877  extern const _Placeholder<14> _14;
878  extern const _Placeholder<15> _15;
879  extern const _Placeholder<16> _16;
880  extern const _Placeholder<17> _17;
881  extern const _Placeholder<18> _18;
882  extern const _Placeholder<19> _19;
883  extern const _Placeholder<20> _20;
884  extern const _Placeholder<21> _21;
885  extern const _Placeholder<22> _22;
886  extern const _Placeholder<23> _23;
887  extern const _Placeholder<24> _24;
888  extern const _Placeholder<25> _25;
889  extern const _Placeholder<26> _26;
890  extern const _Placeholder<27> _27;
891  extern const _Placeholder<28> _28;
892  extern const _Placeholder<29> _29;
893  _GLIBCXX_END_NAMESPACE_VERSION
894  }
895 
896  _GLIBCXX_BEGIN_NAMESPACE_VERSION
897 
898  /**
899  * Partial specialization of is_placeholder that provides the placeholder
900  * number for the placeholder objects defined by libstdc++.
901  * @ingroup binders
902  */
903  template<int _Num>
905  : public integral_constant<int, _Num>
906  { };
907 
908  template<int _Num>
909  struct is_placeholder<const _Placeholder<_Num> >
910  : public integral_constant<int, _Num>
911  { };
912 
913  /**
914  * Used by _Safe_tuple_element to indicate that there is no tuple
915  * element at this position.
916  */
917  struct _No_tuple_element;
918 
919  /**
920  * Implementation helper for _Safe_tuple_element. This primary
921  * template handles the case where it is safe to use @c
922  * tuple_element.
923  */
924  template<std::size_t __i, typename _Tuple, bool _IsSafe>
926  : tuple_element<__i, _Tuple> { };
927 
928  /**
929  * Implementation helper for _Safe_tuple_element. This partial
930  * specialization handles the case where it is not safe to use @c
931  * tuple_element. We just return @c _No_tuple_element.
932  */
933  template<std::size_t __i, typename _Tuple>
934  struct _Safe_tuple_element_impl<__i, _Tuple, false>
935  {
936  typedef _No_tuple_element type;
937  };
938 
939  /**
940  * Like tuple_element, but returns @c _No_tuple_element when
941  * tuple_element would return an error.
942  */
943  template<std::size_t __i, typename _Tuple>
945  : _Safe_tuple_element_impl<__i, _Tuple,
946  (__i < tuple_size<_Tuple>::value)>
947  { };
948 
949  /**
950  * Maps an argument to bind() into an actual argument to the bound
951  * function object [TR1 3.6.3/5]. Only the first parameter should
952  * be specified: the rest are used to determine among the various
953  * implementations. Note that, although this class is a function
954  * object, it isn't entirely normal because it takes only two
955  * parameters regardless of the number of parameters passed to the
956  * bind expression. The first parameter is the bound argument and
957  * the second parameter is a tuple containing references to the
958  * rest of the arguments.
959  */
960  template<typename _Arg,
961  bool _IsBindExp = is_bind_expression<_Arg>::value,
962  bool _IsPlaceholder = (is_placeholder<_Arg>::value > 0)>
963  class _Mu;
964 
965  /**
966  * If the argument is reference_wrapper<_Tp>, returns the
967  * underlying reference. [TR1 3.6.3/5 bullet 1]
968  */
969  template<typename _Tp>
970  class _Mu<reference_wrapper<_Tp>, false, false>
971  {
972  public:
973  typedef _Tp& result_type;
974 
975  /* Note: This won't actually work for const volatile
976  * reference_wrappers, because reference_wrapper::get() is const
977  * but not volatile-qualified. This might be a defect in the TR.
978  */
979  template<typename _CVRef, typename _Tuple>
980  result_type
981  operator()(_CVRef& __arg, _Tuple&) const volatile
982  { return __arg.get(); }
983  };
984 
985  /**
986  * If the argument is a bind expression, we invoke the underlying
987  * function object with the same cv-qualifiers as we are given and
988  * pass along all of our arguments (unwrapped). [TR1 3.6.3/5 bullet 2]
989  */
990  template<typename _Arg>
991  class _Mu<_Arg, true, false>
992  {
993  public:
994  template<typename _CVArg, typename... _Args>
995  auto
996  operator()(_CVArg& __arg,
997  tuple<_Args...>& __tuple) const volatile
998  -> decltype(__arg(declval<_Args>()...))
999  {
1000  // Construct an index tuple and forward to __call
1001  typedef typename _Build_index_tuple<sizeof...(_Args)>::__type
1002  _Indexes;
1003  return this->__call(__arg, __tuple, _Indexes());
1004  }
1005 
1006  private:
1007  // Invokes the underlying function object __arg by unpacking all
1008  // of the arguments in the tuple.
1009  template<typename _CVArg, typename... _Args, std::size_t... _Indexes>
1010  auto
1011  __call(_CVArg& __arg, tuple<_Args...>& __tuple,
1012  const _Index_tuple<_Indexes...>&) const volatile
1013  -> decltype(__arg(declval<_Args>()...))
1014  {
1015  return __arg(std::forward<_Args>(get<_Indexes>(__tuple))...);
1016  }
1017  };
1018 
1019  /**
1020  * If the argument is a placeholder for the Nth argument, returns
1021  * a reference to the Nth argument to the bind function object.
1022  * [TR1 3.6.3/5 bullet 3]
1023  */
1024  template<typename _Arg>
1025  class _Mu<_Arg, false, true>
1026  {
1027  public:
1028  template<typename _Signature> class result;
1029 
1030  template<typename _CVMu, typename _CVArg, typename _Tuple>
1031  class result<_CVMu(_CVArg, _Tuple)>
1032  {
1033  // Add a reference, if it hasn't already been done for us.
1034  // This allows us to be a little bit sloppy in constructing
1035  // the tuple that we pass to result_of<...>.
1037  - 1), _Tuple>::type
1038  __base_type;
1039 
1040  public:
1041  typedef typename add_rvalue_reference<__base_type>::type type;
1042  };
1043 
1044  template<typename _Tuple>
1045  typename result<_Mu(_Arg, _Tuple)>::type
1046  operator()(const volatile _Arg&, _Tuple& __tuple) const volatile
1047  {
1048  return std::forward<typename result<_Mu(_Arg, _Tuple)>::type>(
1049  ::std::get<(is_placeholder<_Arg>::value - 1)>(__tuple));
1050  }
1051  };
1052 
1053  /**
1054  * If the argument is just a value, returns a reference to that
1055  * value. The cv-qualifiers on the reference are the same as the
1056  * cv-qualifiers on the _Mu object. [TR1 3.6.3/5 bullet 4]
1057  */
1058  template<typename _Arg>
1059  class _Mu<_Arg, false, false>
1060  {
1061  public:
1062  template<typename _Signature> struct result;
1063 
1064  template<typename _CVMu, typename _CVArg, typename _Tuple>
1065  struct result<_CVMu(_CVArg, _Tuple)>
1066  {
1067  typedef typename add_lvalue_reference<_CVArg>::type type;
1068  };
1069 
1070  // Pick up the cv-qualifiers of the argument
1071  template<typename _CVArg, typename _Tuple>
1072  _CVArg&&
1073  operator()(_CVArg&& __arg, _Tuple&) const volatile
1074  { return std::forward<_CVArg>(__arg); }
1075  };
1076 
1077  /**
1078  * Maps member pointers into instances of _Mem_fn but leaves all
1079  * other function objects untouched. Used by tr1::bind(). The
1080  * primary template handles the non--member-pointer case.
1081  */
1082  template<typename _Tp>
1084  {
1085  typedef _Tp type;
1086 
1087  static const _Tp&
1088  __do_wrap(const _Tp& __x)
1089  { return __x; }
1090 
1091  static _Tp&&
1092  __do_wrap(_Tp&& __x)
1093  { return static_cast<_Tp&&>(__x); }
1094  };
1095 
1096  /**
1097  * Maps member pointers into instances of _Mem_fn but leaves all
1098  * other function objects untouched. Used by tr1::bind(). This
1099  * partial specialization handles the member pointer case.
1100  */
1101  template<typename _Tp, typename _Class>
1102  struct _Maybe_wrap_member_pointer<_Tp _Class::*>
1103  {
1104  typedef _Mem_fn<_Tp _Class::*> type;
1105 
1106  static type
1107  __do_wrap(_Tp _Class::* __pm)
1108  { return type(__pm); }
1109  };
1110 
1111  // Specialization needed to prevent "forming reference to void" errors when
1112  // bind<void>() is called, because argument deduction instantiates
1113  // _Maybe_wrap_member_pointer<void> outside the immediate context where
1114  // SFINAE applies.
1115  template<>
1116  struct _Maybe_wrap_member_pointer<void>
1117  {
1118  typedef void type;
1119  };
1120 
1121  // std::get<I> for volatile-qualified tuples
1122  template<std::size_t _Ind, typename... _Tp>
1123  inline auto
1124  __volget(volatile tuple<_Tp...>& __tuple)
1125  -> typename tuple_element<_Ind, tuple<_Tp...>>::type volatile&
1126  { return std::get<_Ind>(const_cast<tuple<_Tp...>&>(__tuple)); }
1127 
1128  // std::get<I> for const-volatile-qualified tuples
1129  template<std::size_t _Ind, typename... _Tp>
1130  inline auto
1131  __volget(const volatile tuple<_Tp...>& __tuple)
1132  -> typename tuple_element<_Ind, tuple<_Tp...>>::type const volatile&
1133  { return std::get<_Ind>(const_cast<const tuple<_Tp...>&>(__tuple)); }
1134 
1135  /// Type of the function object returned from bind().
1136  template<typename _Signature>
1137  struct _Bind;
1138 
1139  template<typename _Functor, typename... _Bound_args>
1140  class _Bind<_Functor(_Bound_args...)>
1141  : public _Weak_result_type<_Functor>
1142  {
1143  typedef _Bind __self_type;
1144  typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
1145  _Bound_indexes;
1146 
1147  _Functor _M_f;
1148  tuple<_Bound_args...> _M_bound_args;
1149 
1150  // Call unqualified
1151  template<typename _Result, typename... _Args, std::size_t... _Indexes>
1152  _Result
1153  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
1154  {
1155  return _M_f(_Mu<_Bound_args>()
1156  (get<_Indexes>(_M_bound_args), __args)...);
1157  }
1158 
1159  // Call as const
1160  template<typename _Result, typename... _Args, std::size_t... _Indexes>
1161  _Result
1162  __call_c(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
1163  {
1164  return _M_f(_Mu<_Bound_args>()
1165  (get<_Indexes>(_M_bound_args), __args)...);
1166  }
1167 
1168  // Call as volatile
1169  template<typename _Result, typename... _Args, std::size_t... _Indexes>
1170  _Result
1171  __call_v(tuple<_Args...>&& __args,
1172  _Index_tuple<_Indexes...>) volatile
1173  {
1174  return _M_f(_Mu<_Bound_args>()
1175  (__volget<_Indexes>(_M_bound_args), __args)...);
1176  }
1177 
1178  // Call as const volatile
1179  template<typename _Result, typename... _Args, std::size_t... _Indexes>
1180  _Result
1181  __call_c_v(tuple<_Args...>&& __args,
1182  _Index_tuple<_Indexes...>) const volatile
1183  {
1184  return _M_f(_Mu<_Bound_args>()
1185  (__volget<_Indexes>(_M_bound_args), __args)...);
1186  }
1187 
1188  public:
1189  template<typename... _Args>
1190  explicit _Bind(const _Functor& __f, _Args&&... __args)
1191  : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
1192  { }
1193 
1194  template<typename... _Args>
1195  explicit _Bind(_Functor&& __f, _Args&&... __args)
1196  : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
1197  { }
1198 
1199  _Bind(const _Bind&) = default;
1200 
1201  _Bind(_Bind&& __b)
1202  : _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
1203  { }
1204 
1205  // Call unqualified
1206  template<typename... _Args, typename _Result
1207  = decltype( std::declval<_Functor>()(
1208  _Mu<_Bound_args>()( std::declval<_Bound_args&>(),
1209  std::declval<tuple<_Args...>&>() )... ) )>
1210  _Result
1211  operator()(_Args&&... __args)
1212  {
1213  return this->__call<_Result>(
1214  std::forward_as_tuple(std::forward<_Args>(__args)...),
1215  _Bound_indexes());
1216  }
1217 
1218  // Call as const
1219  template<typename... _Args, typename _Result
1220  = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
1221  typename add_const<_Functor>::type>::type>()(
1222  _Mu<_Bound_args>()( std::declval<const _Bound_args&>(),
1223  std::declval<tuple<_Args...>&>() )... ) )>
1224  _Result
1225  operator()(_Args&&... __args) const
1226  {
1227  return this->__call_c<_Result>(
1228  std::forward_as_tuple(std::forward<_Args>(__args)...),
1229  _Bound_indexes());
1230  }
1231 
1232  // Call as volatile
1233  template<typename... _Args, typename _Result
1234  = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
1235  typename add_volatile<_Functor>::type>::type>()(
1236  _Mu<_Bound_args>()( std::declval<volatile _Bound_args&>(),
1237  std::declval<tuple<_Args...>&>() )... ) )>
1238  _Result
1239  operator()(_Args&&... __args) volatile
1240  {
1241  return this->__call_v<_Result>(
1242  std::forward_as_tuple(std::forward<_Args>(__args)...),
1243  _Bound_indexes());
1244  }
1245 
1246  // Call as const volatile
1247  template<typename... _Args, typename _Result
1248  = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
1249  typename add_cv<_Functor>::type>::type>()(
1250  _Mu<_Bound_args>()( std::declval<const volatile _Bound_args&>(),
1251  std::declval<tuple<_Args...>&>() )... ) )>
1252  _Result
1253  operator()(_Args&&... __args) const volatile
1254  {
1255  return this->__call_c_v<_Result>(
1256  std::forward_as_tuple(std::forward<_Args>(__args)...),
1257  _Bound_indexes());
1258  }
1259  };
1260 
1261  /// Type of the function object returned from bind<R>().
1262  template<typename _Result, typename _Signature>
1263  struct _Bind_result;
1264 
1265  template<typename _Result, typename _Functor, typename... _Bound_args>
1266  class _Bind_result<_Result, _Functor(_Bound_args...)>
1267  {
1268  typedef _Bind_result __self_type;
1269  typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
1270  _Bound_indexes;
1271 
1272  _Functor _M_f;
1273  tuple<_Bound_args...> _M_bound_args;
1274 
1275  // sfinae types
1276  template<typename _Res>
1277  struct __enable_if_void : enable_if<is_void<_Res>::value, int> { };
1278  template<typename _Res>
1279  struct __disable_if_void : enable_if<!is_void<_Res>::value, int> { };
1280 
1281  // Call unqualified
1282  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1283  _Result
1284  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1285  typename __disable_if_void<_Res>::type = 0)
1286  {
1287  return _M_f(_Mu<_Bound_args>()
1288  (get<_Indexes>(_M_bound_args), __args)...);
1289  }
1290 
1291  // Call unqualified, return void
1292  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1293  void
1294  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1295  typename __enable_if_void<_Res>::type = 0)
1296  {
1297  _M_f(_Mu<_Bound_args>()
1298  (get<_Indexes>(_M_bound_args), __args)...);
1299  }
1300 
1301  // Call as const
1302  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1303  _Result
1304  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1305  typename __disable_if_void<_Res>::type = 0) const
1306  {
1307  return _M_f(_Mu<_Bound_args>()
1308  (get<_Indexes>(_M_bound_args), __args)...);
1309  }
1310 
1311  // Call as const, return void
1312  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1313  void
1314  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1315  typename __enable_if_void<_Res>::type = 0) const
1316  {
1317  _M_f(_Mu<_Bound_args>()
1318  (get<_Indexes>(_M_bound_args), __args)...);
1319  }
1320 
1321  // Call as volatile
1322  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1323  _Result
1324  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1325  typename __disable_if_void<_Res>::type = 0) volatile
1326  {
1327  return _M_f(_Mu<_Bound_args>()
1328  (__volget<_Indexes>(_M_bound_args), __args)...);
1329  }
1330 
1331  // Call as volatile, return void
1332  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1333  void
1334  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1335  typename __enable_if_void<_Res>::type = 0) volatile
1336  {
1337  _M_f(_Mu<_Bound_args>()
1338  (__volget<_Indexes>(_M_bound_args), __args)...);
1339  }
1340 
1341  // Call as const volatile
1342  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1343  _Result
1344  __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
1345  typename __disable_if_void<_Res>::type = 0) const volatile
1346  {
1347  return _M_f(_Mu<_Bound_args>()
1348  (__volget<_Indexes>(_M_bound_args), __args)...);
1349  }
1350 
1351  // Call as const volatile, return void
1352  template<typename _Res, typename... _Args, std::size_t... _Indexes>
1353  void
1354  __call(tuple<_Args...>&& __args,
1355  _Index_tuple<_Indexes...>,
1356  typename __enable_if_void<_Res>::type = 0) const volatile
1357  {
1358  _M_f(_Mu<_Bound_args>()
1359  (__volget<_Indexes>(_M_bound_args), __args)...);
1360  }
1361 
1362  public:
1363  typedef _Result result_type;
1364 
1365  template<typename... _Args>
1366  explicit _Bind_result(const _Functor& __f, _Args&&... __args)
1367  : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
1368  { }
1369 
1370  template<typename... _Args>
1371  explicit _Bind_result(_Functor&& __f, _Args&&... __args)
1372  : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
1373  { }
1374 
1375  _Bind_result(const _Bind_result&) = default;
1376 
1377  _Bind_result(_Bind_result&& __b)
1378  : _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
1379  { }
1380 
1381  // Call unqualified
1382  template<typename... _Args>
1383  result_type
1384  operator()(_Args&&... __args)
1385  {
1386  return this->__call<_Result>(
1387  std::forward_as_tuple(std::forward<_Args>(__args)...),
1388  _Bound_indexes());
1389  }
1390 
1391  // Call as const
1392  template<typename... _Args>
1393  result_type
1394  operator()(_Args&&... __args) const
1395  {
1396  return this->__call<_Result>(
1397  std::forward_as_tuple(std::forward<_Args>(__args)...),
1398  _Bound_indexes());
1399  }
1400 
1401  // Call as volatile
1402  template<typename... _Args>
1403  result_type
1404  operator()(_Args&&... __args) volatile
1405  {
1406  return this->__call<_Result>(
1407  std::forward_as_tuple(std::forward<_Args>(__args)...),
1408  _Bound_indexes());
1409  }
1410 
1411  // Call as const volatile
1412  template<typename... _Args>
1413  result_type
1414  operator()(_Args&&... __args) const volatile
1415  {
1416  return this->__call<_Result>(
1417  std::forward_as_tuple(std::forward<_Args>(__args)...),
1418  _Bound_indexes());
1419  }
1420  };
1421 
1422  /**
1423  * @brief Class template _Bind is always a bind expression.
1424  * @ingroup binders
1425  */
1426  template<typename _Signature>
1427  struct is_bind_expression<_Bind<_Signature> >
1428  : public true_type { };
1429 
1430  /**
1431  * @brief Class template _Bind is always a bind expression.
1432  * @ingroup binders
1433  */
1434  template<typename _Signature>
1435  struct is_bind_expression<const _Bind<_Signature> >
1436  : public true_type { };
1437 
1438  /**
1439  * @brief Class template _Bind is always a bind expression.
1440  * @ingroup binders
1441  */
1442  template<typename _Signature>
1443  struct is_bind_expression<volatile _Bind<_Signature> >
1444  : public true_type { };
1445 
1446  /**
1447  * @brief Class template _Bind is always a bind expression.
1448  * @ingroup binders
1449  */
1450  template<typename _Signature>
1451  struct is_bind_expression<const volatile _Bind<_Signature>>
1452  : public true_type { };
1453 
1454  /**
1455  * @brief Class template _Bind_result is always a bind expression.
1456  * @ingroup binders
1457  */
1458  template<typename _Result, typename _Signature>
1459  struct is_bind_expression<_Bind_result<_Result, _Signature>>
1460  : public true_type { };
1461 
1462  /**
1463  * @brief Class template _Bind_result is always a bind expression.
1464  * @ingroup binders
1465  */
1466  template<typename _Result, typename _Signature>
1467  struct is_bind_expression<const _Bind_result<_Result, _Signature>>
1468  : public true_type { };
1469 
1470  /**
1471  * @brief Class template _Bind_result is always a bind expression.
1472  * @ingroup binders
1473  */
1474  template<typename _Result, typename _Signature>
1475  struct is_bind_expression<volatile _Bind_result<_Result, _Signature>>
1476  : public true_type { };
1477 
1478  /**
1479  * @brief Class template _Bind_result is always a bind expression.
1480  * @ingroup binders
1481  */
1482  template<typename _Result, typename _Signature>
1483  struct is_bind_expression<const volatile _Bind_result<_Result, _Signature>>
1484  : public true_type { };
1485 
1486  // Trait type used to remove std::bind() from overload set via SFINAE
1487  // when first argument has integer type, so that std::bind() will
1488  // not be a better match than ::bind() from the BSD Sockets API.
1489  template<typename _Tp>
1490  class __is_socketlike
1491  {
1492  typedef typename decay<_Tp>::type _Tp2;
1493  public:
1494  static const bool value =
1496  };
1497 
1498  template<bool _SocketLike, typename _Func, typename... _BoundArgs>
1499  struct _Bind_helper
1500  {
1501  typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
1502  __maybe_type;
1503  typedef typename __maybe_type::type __func_type;
1504  typedef _Bind<__func_type(typename decay<_BoundArgs>::type...)> type;
1505  };
1506 
1507  // Partial specialization for is_socketlike == true, does not define
1508  // nested type so std::bind() will not participate in overload resolution
1509  // when the first argument might be a socket file descriptor.
1510  template<typename _Func, typename... _BoundArgs>
1511  struct _Bind_helper<true, _Func, _BoundArgs...>
1512  { };
1513 
1514  /**
1515  * @brief Function template for std::bind.
1516  * @ingroup binders
1517  */
1518  template<typename _Func, typename... _BoundArgs>
1519  inline typename
1520  _Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type
1521  bind(_Func&& __f, _BoundArgs&&... __args)
1522  {
1523  typedef _Bind_helper<false, _Func, _BoundArgs...> __helper_type;
1524  typedef typename __helper_type::__maybe_type __maybe_type;
1525  typedef typename __helper_type::type __result_type;
1526  return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
1527  std::forward<_BoundArgs>(__args)...);
1528  }
1529 
1530  template<typename _Result, typename _Func, typename... _BoundArgs>
1531  struct _Bindres_helper
1532  {
1533  typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
1534  __maybe_type;
1535  typedef typename __maybe_type::type __functor_type;
1536  typedef _Bind_result<_Result,
1537  __functor_type(typename decay<_BoundArgs>::type...)>
1538  type;
1539  };
1540 
1541  /**
1542  * @brief Function template for std::bind<R>.
1543  * @ingroup binders
1544  */
1545  template<typename _Result, typename _Func, typename... _BoundArgs>
1546  inline
1547  typename _Bindres_helper<_Result, _Func, _BoundArgs...>::type
1548  bind(_Func&& __f, _BoundArgs&&... __args)
1549  {
1550  typedef _Bindres_helper<_Result, _Func, _BoundArgs...> __helper_type;
1551  typedef typename __helper_type::__maybe_type __maybe_type;
1552  typedef typename __helper_type::type __result_type;
1553  return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
1554  std::forward<_BoundArgs>(__args)...);
1555  }
1556 
1557  template<typename _Signature>
1558  struct _Bind_simple;
1559 
1560  template<typename _Callable, typename... _Args>
1561  struct _Bind_simple<_Callable(_Args...)>
1562  {
1563  typedef typename result_of<_Callable(_Args...)>::type result_type;
1564 
1565  template<typename... _Args2, typename = typename
1566  enable_if< sizeof...(_Args) == sizeof...(_Args2)>::type>
1567  explicit
1568  _Bind_simple(const _Callable& __callable, _Args2&&... __args)
1569  : _M_bound(__callable, std::forward<_Args2>(__args)...)
1570  { }
1571 
1572  template<typename... _Args2, typename = typename
1573  enable_if< sizeof...(_Args) == sizeof...(_Args2)>::type>
1574  explicit
1575  _Bind_simple(_Callable&& __callable, _Args2&&... __args)
1576  : _M_bound(std::move(__callable), std::forward<_Args2>(__args)...)
1577  { }
1578 
1579  _Bind_simple(const _Bind_simple&) = default;
1580  _Bind_simple(_Bind_simple&&) = default;
1581 
1582  result_type
1583  operator()()
1584  {
1585  typedef typename _Build_index_tuple<sizeof...(_Args)>::__type _Indices;
1586  return _M_invoke(_Indices());
1587  }
1588 
1589  private:
1590 
1591  template<std::size_t... _Indices>
1592  typename result_of<_Callable(_Args...)>::type
1593  _M_invoke(_Index_tuple<_Indices...>)
1594  {
1595  // std::bind always forwards bound arguments as lvalues,
1596  // but this type can call functions which only accept rvalues.
1597  return std::forward<_Callable>(std::get<0>(_M_bound))(
1598  std::forward<_Args>(std::get<_Indices+1>(_M_bound))...);
1599  }
1600 
1601  std::tuple<_Callable, _Args...> _M_bound;
1602  };
1603 
1604  template<typename _Func, typename... _BoundArgs>
1605  struct _Bind_simple_helper
1606  {
1607  typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
1608  __maybe_type;
1609  typedef typename __maybe_type::type __func_type;
1610  typedef _Bind_simple<__func_type(typename decay<_BoundArgs>::type...)>
1611  __type;
1612  };
1613 
1614  // Simplified version of std::bind for internal use, without support for
1615  // unbound arguments, placeholders or nested bind expressions.
1616  template<typename _Callable, typename... _Args>
1617  typename _Bind_simple_helper<_Callable, _Args...>::__type
1618  __bind_simple(_Callable&& __callable, _Args&&... __args)
1619  {
1620  typedef _Bind_simple_helper<_Callable, _Args...> __helper_type;
1621  typedef typename __helper_type::__maybe_type __maybe_type;
1622  typedef typename __helper_type::__type __result_type;
1623  return __result_type(
1624  __maybe_type::__do_wrap( std::forward<_Callable>(__callable)),
1625  std::forward<_Args>(__args)...);
1626  }
1627 
1628  /**
1629  * @brief Exception class thrown when class template function's
1630  * operator() is called with an empty target.
1631  * @ingroup exceptions
1632  */
1634  {
1635  public:
1636  virtual ~bad_function_call() noexcept;
1637  };
1638 
1639  /**
1640  * Trait identifying "location-invariant" types, meaning that the
1641  * address of the object (or any of its members) will not escape.
1642  * Also implies a trivial copy constructor and assignment operator.
1643  */
1644  template<typename _Tp>
1646  : integral_constant<bool, (is_pointer<_Tp>::value
1647  || is_member_pointer<_Tp>::value)>
1648  { };
1649 
1650  class _Undefined_class;
1651 
1652  union _Nocopy_types
1653  {
1654  void* _M_object;
1655  const void* _M_const_object;
1656  void (*_M_function_pointer)();
1657  void (_Undefined_class::*_M_member_pointer)();
1658  };
1659 
1660  union _Any_data
1661  {
1662  void* _M_access() { return &_M_pod_data[0]; }
1663  const void* _M_access() const { return &_M_pod_data[0]; }
1664 
1665  template<typename _Tp>
1666  _Tp&
1667  _M_access()
1668  { return *static_cast<_Tp*>(_M_access()); }
1669 
1670  template<typename _Tp>
1671  const _Tp&
1672  _M_access() const
1673  { return *static_cast<const _Tp*>(_M_access()); }
1674 
1675  _Nocopy_types _M_unused;
1676  char _M_pod_data[sizeof(_Nocopy_types)];
1677  };
1678 
1679  enum _Manager_operation
1680  {
1681  __get_type_info,
1682  __get_functor_ptr,
1683  __clone_functor,
1684  __destroy_functor
1685  };
1686 
1687  // Simple type wrapper that helps avoid annoying const problems
1688  // when casting between void pointers and pointers-to-pointers.
1689  template<typename _Tp>
1690  struct _Simple_type_wrapper
1691  {
1692  _Simple_type_wrapper(_Tp __value) : __value(__value) { }
1693 
1694  _Tp __value;
1695  };
1696 
1697  template<typename _Tp>
1698  struct __is_location_invariant<_Simple_type_wrapper<_Tp> >
1699  : __is_location_invariant<_Tp>
1700  { };
1701 
1702  // Converts a reference to a function object into a callable
1703  // function object.
1704  template<typename _Functor>
1705  inline _Functor&
1706  __callable_functor(_Functor& __f)
1707  { return __f; }
1708 
1709  template<typename _Member, typename _Class>
1710  inline _Mem_fn<_Member _Class::*>
1711  __callable_functor(_Member _Class::* &__p)
1712  { return mem_fn(__p); }
1713 
1714  template<typename _Member, typename _Class>
1715  inline _Mem_fn<_Member _Class::*>
1716  __callable_functor(_Member _Class::* const &__p)
1717  { return mem_fn(__p); }
1718 
1719  template<typename _Signature>
1720  class function;
1721 
1722  /// Base class of all polymorphic function object wrappers.
1724  {
1725  public:
1726  static const std::size_t _M_max_size = sizeof(_Nocopy_types);
1727  static const std::size_t _M_max_align = __alignof__(_Nocopy_types);
1728 
1729  template<typename _Functor>
1730  class _Base_manager
1731  {
1732  protected:
1733  static const bool __stored_locally =
1735  && sizeof(_Functor) <= _M_max_size
1736  && __alignof__(_Functor) <= _M_max_align
1737  && (_M_max_align % __alignof__(_Functor) == 0));
1738 
1739  typedef integral_constant<bool, __stored_locally> _Local_storage;
1740 
1741  // Retrieve a pointer to the function object
1742  static _Functor*
1743  _M_get_pointer(const _Any_data& __source)
1744  {
1745  const _Functor* __ptr =
1746  __stored_locally? std::__addressof(__source._M_access<_Functor>())
1747  /* have stored a pointer */ : __source._M_access<_Functor*>();
1748  return const_cast<_Functor*>(__ptr);
1749  }
1750 
1751  // Clone a location-invariant function object that fits within
1752  // an _Any_data structure.
1753  static void
1754  _M_clone(_Any_data& __dest, const _Any_data& __source, true_type)
1755  {
1756  new (__dest._M_access()) _Functor(__source._M_access<_Functor>());
1757  }
1758 
1759  // Clone a function object that is not location-invariant or
1760  // that cannot fit into an _Any_data structure.
1761  static void
1762  _M_clone(_Any_data& __dest, const _Any_data& __source, false_type)
1763  {
1764  __dest._M_access<_Functor*>() =
1765  new _Functor(*__source._M_access<_Functor*>());
1766  }
1767 
1768  // Destroying a location-invariant object may still require
1769  // destruction.
1770  static void
1771  _M_destroy(_Any_data& __victim, true_type)
1772  {
1773  __victim._M_access<_Functor>().~_Functor();
1774  }
1775 
1776  // Destroying an object located on the heap.
1777  static void
1778  _M_destroy(_Any_data& __victim, false_type)
1779  {
1780  delete __victim._M_access<_Functor*>();
1781  }
1782 
1783  public:
1784  static bool
1785  _M_manager(_Any_data& __dest, const _Any_data& __source,
1786  _Manager_operation __op)
1787  {
1788  switch (__op)
1789  {
1790 #ifdef __GXX_RTTI
1791  case __get_type_info:
1792  __dest._M_access<const type_info*>() = &typeid(_Functor);
1793  break;
1794 #endif
1795  case __get_functor_ptr:
1796  __dest._M_access<_Functor*>() = _M_get_pointer(__source);
1797  break;
1798 
1799  case __clone_functor:
1800  _M_clone(__dest, __source, _Local_storage());
1801  break;
1802 
1803  case __destroy_functor:
1804  _M_destroy(__dest, _Local_storage());
1805  break;
1806  }
1807  return false;
1808  }
1809 
1810  static void
1811  _M_init_functor(_Any_data& __functor, _Functor&& __f)
1812  { _M_init_functor(__functor, std::move(__f), _Local_storage()); }
1813 
1814  template<typename _Signature>
1815  static bool
1816  _M_not_empty_function(const function<_Signature>& __f)
1817  { return static_cast<bool>(__f); }
1818 
1819  template<typename _Tp>
1820  static bool
1821  _M_not_empty_function(const _Tp*& __fp)
1822  { return __fp; }
1823 
1824  template<typename _Class, typename _Tp>
1825  static bool
1826  _M_not_empty_function(_Tp _Class::* const& __mp)
1827  { return __mp; }
1828 
1829  template<typename _Tp>
1830  static bool
1831  _M_not_empty_function(const _Tp&)
1832  { return true; }
1833 
1834  private:
1835  static void
1836  _M_init_functor(_Any_data& __functor, _Functor&& __f, true_type)
1837  { new (__functor._M_access()) _Functor(std::move(__f)); }
1838 
1839  static void
1840  _M_init_functor(_Any_data& __functor, _Functor&& __f, false_type)
1841  { __functor._M_access<_Functor*>() = new _Functor(std::move(__f)); }
1842  };
1843 
1844  template<typename _Functor>
1845  class _Ref_manager : public _Base_manager<_Functor*>
1846  {
1847  typedef _Function_base::_Base_manager<_Functor*> _Base;
1848 
1849  public:
1850  static bool
1851  _M_manager(_Any_data& __dest, const _Any_data& __source,
1852  _Manager_operation __op)
1853  {
1854  switch (__op)
1855  {
1856 #ifdef __GXX_RTTI
1857  case __get_type_info:
1858  __dest._M_access<const type_info*>() = &typeid(_Functor);
1859  break;
1860 #endif
1861  case __get_functor_ptr:
1862  __dest._M_access<_Functor*>() = *_Base::_M_get_pointer(__source);
1864  break;
1865 
1866  default:
1867  _Base::_M_manager(__dest, __source, __op);
1868  }
1869  return false;
1870  }
1871 
1872  static void
1873  _M_init_functor(_Any_data& __functor, reference_wrapper<_Functor> __f)
1874  {
1875  // TBD: Use address_of function instead.
1876  _Base::_M_init_functor(__functor, &__f.get());
1877  }
1878  };
1879 
1880  _Function_base() : _M_manager(0) { }
1881 
1882  ~_Function_base()
1883  {
1884  if (_M_manager)
1885  _M_manager(_M_functor, _M_functor, __destroy_functor);
1886  }
1887 
1888 
1889  bool _M_empty() const { return !_M_manager; }
1890 
1891  typedef bool (*_Manager_type)(_Any_data&, const _Any_data&,
1892  _Manager_operation);
1893 
1894  _Any_data _M_functor;
1895  _Manager_type _M_manager;
1896  };
1897 
1898  template<typename _Signature, typename _Functor>
1899  class _Function_handler;
1900 
1901  template<typename _Res, typename _Functor, typename... _ArgTypes>
1902  class _Function_handler<_Res(_ArgTypes...), _Functor>
1903  : public _Function_base::_Base_manager<_Functor>
1904  {
1905  typedef _Function_base::_Base_manager<_Functor> _Base;
1906 
1907  public:
1908  static _Res
1909  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
1910  {
1911  return (*_Base::_M_get_pointer(__functor))(
1912  std::forward<_ArgTypes>(__args)...);
1913  }
1914  };
1915 
1916  template<typename _Functor, typename... _ArgTypes>
1917  class _Function_handler<void(_ArgTypes...), _Functor>
1918  : public _Function_base::_Base_manager<_Functor>
1919  {
1920  typedef _Function_base::_Base_manager<_Functor> _Base;
1921 
1922  public:
1923  static void
1924  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
1925  {
1926  (*_Base::_M_get_pointer(__functor))(
1927  std::forward<_ArgTypes>(__args)...);
1928  }
1929  };
1930 
1931  template<typename _Res, typename _Functor, typename... _ArgTypes>
1932  class _Function_handler<_Res(_ArgTypes...), reference_wrapper<_Functor> >
1933  : public _Function_base::_Ref_manager<_Functor>
1934  {
1935  typedef _Function_base::_Ref_manager<_Functor> _Base;
1936 
1937  public:
1938  static _Res
1939  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
1940  {
1941  return __callable_functor(**_Base::_M_get_pointer(__functor))(
1942  std::forward<_ArgTypes>(__args)...);
1943  }
1944  };
1945 
1946  template<typename _Functor, typename... _ArgTypes>
1947  class _Function_handler<void(_ArgTypes...), reference_wrapper<_Functor> >
1948  : public _Function_base::_Ref_manager<_Functor>
1949  {
1950  typedef _Function_base::_Ref_manager<_Functor> _Base;
1951 
1952  public:
1953  static void
1954  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
1955  {
1956  __callable_functor(**_Base::_M_get_pointer(__functor))(
1957  std::forward<_ArgTypes>(__args)...);
1958  }
1959  };
1960 
1961  template<typename _Class, typename _Member, typename _Res,
1962  typename... _ArgTypes>
1963  class _Function_handler<_Res(_ArgTypes...), _Member _Class::*>
1964  : public _Function_handler<void(_ArgTypes...), _Member _Class::*>
1965  {
1966  typedef _Function_handler<void(_ArgTypes...), _Member _Class::*>
1967  _Base;
1968 
1969  public:
1970  static _Res
1971  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
1972  {
1973  return mem_fn(_Base::_M_get_pointer(__functor)->__value)(
1974  std::forward<_ArgTypes>(__args)...);
1975  }
1976  };
1977 
1978  template<typename _Class, typename _Member, typename... _ArgTypes>
1979  class _Function_handler<void(_ArgTypes...), _Member _Class::*>
1980  : public _Function_base::_Base_manager<
1981  _Simple_type_wrapper< _Member _Class::* > >
1982  {
1983  typedef _Member _Class::* _Functor;
1984  typedef _Simple_type_wrapper<_Functor> _Wrapper;
1985  typedef _Function_base::_Base_manager<_Wrapper> _Base;
1986 
1987  public:
1988  static bool
1989  _M_manager(_Any_data& __dest, const _Any_data& __source,
1990  _Manager_operation __op)
1991  {
1992  switch (__op)
1993  {
1994 #ifdef __GXX_RTTI
1995  case __get_type_info:
1996  __dest._M_access<const type_info*>() = &typeid(_Functor);
1997  break;
1998 #endif
1999  case __get_functor_ptr:
2000  __dest._M_access<_Functor*>() =
2001  &_Base::_M_get_pointer(__source)->__value;
2002  break;
2003 
2004  default:
2005  _Base::_M_manager(__dest, __source, __op);
2006  }
2007  return false;
2008  }
2009 
2010  static void
2011  _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
2012  {
2013  mem_fn(_Base::_M_get_pointer(__functor)->__value)(
2014  std::forward<_ArgTypes>(__args)...);
2015  }
2016  };
2017 
2018  /**
2019  * @brief Primary class template for std::function.
2020  * @ingroup functors
2021  *
2022  * Polymorphic function wrapper.
2023  */
2024  template<typename _Res, typename... _ArgTypes>
2025  class function<_Res(_ArgTypes...)>
2026  : public _Maybe_unary_or_binary_function<_Res, _ArgTypes...>,
2027  private _Function_base
2028  {
2029  typedef _Res _Signature_type(_ArgTypes...);
2030 
2031  struct _Useless { };
2032 
2033  public:
2034  typedef _Res result_type;
2035 
2036  // [3.7.2.1] construct/copy/destroy
2037 
2038  /**
2039  * @brief Default construct creates an empty function call wrapper.
2040  * @post @c !(bool)*this
2041  */
2042  function() noexcept
2043  : _Function_base() { }
2044 
2045  /**
2046  * @brief Creates an empty function call wrapper.
2047  * @post @c !(bool)*this
2048  */
2049  function(nullptr_t) noexcept
2050  : _Function_base() { }
2051 
2052  /**
2053  * @brief %Function copy constructor.
2054  * @param __x A %function object with identical call signature.
2055  * @post @c bool(*this) == bool(__x)
2056  *
2057  * The newly-created %function contains a copy of the target of @a
2058  * __x (if it has one).
2059  */
2060  function(const function& __x);
2061 
2062  /**
2063  * @brief %Function move constructor.
2064  * @param __x A %function object rvalue with identical call signature.
2065  *
2066  * The newly-created %function contains the target of @a __x
2067  * (if it has one).
2068  */
2069  function(function&& __x) : _Function_base()
2070  {
2071  __x.swap(*this);
2072  }
2073 
2074  // TODO: needs allocator_arg_t
2075 
2076  /**
2077  * @brief Builds a %function that targets a copy of the incoming
2078  * function object.
2079  * @param __f A %function object that is callable with parameters of
2080  * type @c T1, @c T2, ..., @c TN and returns a value convertible
2081  * to @c Res.
2082  *
2083  * The newly-created %function object will target a copy of
2084  * @a __f. If @a __f is @c reference_wrapper<F>, then this function
2085  * object will contain a reference to the function object @c
2086  * __f.get(). If @a __f is a NULL function pointer or NULL
2087  * pointer-to-member, the newly-created object will be empty.
2088  *
2089  * If @a __f is a non-NULL function pointer or an object of type @c
2090  * reference_wrapper<F>, this function will not throw.
2091  */
2092  template<typename _Functor>
2093  function(_Functor __f,
2094  typename enable_if<
2095  !is_integral<_Functor>::value, _Useless>::type
2096  = _Useless());
2097 
2098  /**
2099  * @brief %Function assignment operator.
2100  * @param __x A %function with identical call signature.
2101  * @post @c (bool)*this == (bool)x
2102  * @returns @c *this
2103  *
2104  * The target of @a __x is copied to @c *this. If @a __x has no
2105  * target, then @c *this will be empty.
2106  *
2107  * If @a __x targets a function pointer or a reference to a function
2108  * object, then this operation will not throw an %exception.
2109  */
2110  function&
2111  operator=(const function& __x)
2112  {
2113  function(__x).swap(*this);
2114  return *this;
2115  }
2116 
2117  /**
2118  * @brief %Function move-assignment operator.
2119  * @param __x A %function rvalue with identical call signature.
2120  * @returns @c *this
2121  *
2122  * The target of @a __x is moved to @c *this. If @a __x has no
2123  * target, then @c *this will be empty.
2124  *
2125  * If @a __x targets a function pointer or a reference to a function
2126  * object, then this operation will not throw an %exception.
2127  */
2128  function&
2129  operator=(function&& __x)
2130  {
2131  function(std::move(__x)).swap(*this);
2132  return *this;
2133  }
2134 
2135  /**
2136  * @brief %Function assignment to zero.
2137  * @post @c !(bool)*this
2138  * @returns @c *this
2139  *
2140  * The target of @c *this is deallocated, leaving it empty.
2141  */
2142  function&
2143  operator=(nullptr_t)
2144  {
2145  if (_M_manager)
2146  {
2147  _M_manager(_M_functor, _M_functor, __destroy_functor);
2148  _M_manager = 0;
2149  _M_invoker = 0;
2150  }
2151  return *this;
2152  }
2153 
2154  /**
2155  * @brief %Function assignment to a new target.
2156  * @param __f A %function object that is callable with parameters of
2157  * type @c T1, @c T2, ..., @c TN and returns a value convertible
2158  * to @c Res.
2159  * @return @c *this
2160  *
2161  * This %function object wrapper will target a copy of @a
2162  * __f. If @a __f is @c reference_wrapper<F>, then this function
2163  * object will contain a reference to the function object @c
2164  * __f.get(). If @a __f is a NULL function pointer or NULL
2165  * pointer-to-member, @c this object will be empty.
2166  *
2167  * If @a __f is a non-NULL function pointer or an object of type @c
2168  * reference_wrapper<F>, this function will not throw.
2169  */
2170  template<typename _Functor>
2171  typename enable_if<!is_integral<_Functor>::value, function&>::type
2172  operator=(_Functor&& __f)
2173  {
2174  function(std::forward<_Functor>(__f)).swap(*this);
2175  return *this;
2176  }
2177 
2178  /// @overload
2179  template<typename _Functor>
2180  typename enable_if<!is_integral<_Functor>::value, function&>::type
2181  operator=(reference_wrapper<_Functor> __f) noexcept
2182  {
2183  function(__f).swap(*this);
2184  return *this;
2185  }
2186 
2187  // [3.7.2.2] function modifiers
2188 
2189  /**
2190  * @brief Swap the targets of two %function objects.
2191  * @param __x A %function with identical call signature.
2192  *
2193  * Swap the targets of @c this function object and @a __f. This
2194  * function will not throw an %exception.
2195  */
2196  void swap(function& __x)
2197  {
2198  std::swap(_M_functor, __x._M_functor);
2199  std::swap(_M_manager, __x._M_manager);
2200  std::swap(_M_invoker, __x._M_invoker);
2201  }
2202 
2203  // TODO: needs allocator_arg_t
2204  /*
2205  template<typename _Functor, typename _Alloc>
2206  void
2207  assign(_Functor&& __f, const _Alloc& __a)
2208  {
2209  function(allocator_arg, __a,
2210  std::forward<_Functor>(__f)).swap(*this);
2211  }
2212  */
2213 
2214  // [3.7.2.3] function capacity
2215 
2216  /**
2217  * @brief Determine if the %function wrapper has a target.
2218  *
2219  * @return @c true when this %function object contains a target,
2220  * or @c false when it is empty.
2221  *
2222  * This function will not throw an %exception.
2223  */
2224  explicit operator bool() const noexcept
2225  { return !_M_empty(); }
2226 
2227  // [3.7.2.4] function invocation
2228 
2229  /**
2230  * @brief Invokes the function targeted by @c *this.
2231  * @returns the result of the target.
2232  * @throws bad_function_call when @c !(bool)*this
2233  *
2234  * The function call operator invokes the target function object
2235  * stored by @c this.
2236  */
2237  _Res operator()(_ArgTypes... __args) const;
2238 
2239 #ifdef __GXX_RTTI
2240  // [3.7.2.5] function target access
2241  /**
2242  * @brief Determine the type of the target of this function object
2243  * wrapper.
2244  *
2245  * @returns the type identifier of the target function object, or
2246  * @c typeid(void) if @c !(bool)*this.
2247  *
2248  * This function will not throw an %exception.
2249  */
2250  const type_info& target_type() const noexcept;
2251 
2252  /**
2253  * @brief Access the stored target function object.
2254  *
2255  * @return Returns a pointer to the stored target function object,
2256  * if @c typeid(Functor).equals(target_type()); otherwise, a NULL
2257  * pointer.
2258  *
2259  * This function will not throw an %exception.
2260  */
2261  template<typename _Functor> _Functor* target() noexcept;
2262 
2263  /// @overload
2264  template<typename _Functor> const _Functor* target() const noexcept;
2265 #endif
2266 
2267  private:
2268  typedef _Res (*_Invoker_type)(const _Any_data&, _ArgTypes...);
2269  _Invoker_type _M_invoker;
2270  };
2271 
2272  // Out-of-line member definitions.
2273  template<typename _Res, typename... _ArgTypes>
2274  function<_Res(_ArgTypes...)>::
2275  function(const function& __x)
2276  : _Function_base()
2277  {
2278  if (static_cast<bool>(__x))
2279  {
2280  _M_invoker = __x._M_invoker;
2281  _M_manager = __x._M_manager;
2282  __x._M_manager(_M_functor, __x._M_functor, __clone_functor);
2283  }
2284  }
2285 
2286  template<typename _Res, typename... _ArgTypes>
2287  template<typename _Functor>
2288  function<_Res(_ArgTypes...)>::
2289  function(_Functor __f,
2290  typename enable_if<
2291  !is_integral<_Functor>::value, _Useless>::type)
2292  : _Function_base()
2293  {
2294  typedef _Function_handler<_Signature_type, _Functor> _My_handler;
2295 
2296  if (_My_handler::_M_not_empty_function(__f))
2297  {
2298  _M_invoker = &_My_handler::_M_invoke;
2299  _M_manager = &_My_handler::_M_manager;
2300  _My_handler::_M_init_functor(_M_functor, std::move(__f));
2301  }
2302  }
2303 
2304  template<typename _Res, typename... _ArgTypes>
2305  _Res
2306  function<_Res(_ArgTypes...)>::
2307  operator()(_ArgTypes... __args) const
2308  {
2309  if (_M_empty())
2310  __throw_bad_function_call();
2311  return _M_invoker(_M_functor, std::forward<_ArgTypes>(__args)...);
2312  }
2313 
2314 #ifdef __GXX_RTTI
2315  template<typename _Res, typename... _ArgTypes>
2316  const type_info&
2317  function<_Res(_ArgTypes...)>::
2318  target_type() const noexcept
2319  {
2320  if (_M_manager)
2321  {
2322  _Any_data __typeinfo_result;
2323  _M_manager(__typeinfo_result, _M_functor, __get_type_info);
2324  return *__typeinfo_result._M_access<const type_info*>();
2325  }
2326  else
2327  return typeid(void);
2328  }
2329 
2330  template<typename _Res, typename... _ArgTypes>
2331  template<typename _Functor>
2332  _Functor*
2333  function<_Res(_ArgTypes...)>::
2334  target() noexcept
2335  {
2336  if (typeid(_Functor) == target_type() && _M_manager)
2337  {
2338  _Any_data __ptr;
2339  if (_M_manager(__ptr, _M_functor, __get_functor_ptr)
2341  return 0;
2342  else
2343  return __ptr._M_access<_Functor*>();
2344  }
2345  else
2346  return 0;
2347  }
2348 
2349  template<typename _Res, typename... _ArgTypes>
2350  template<typename _Functor>
2351  const _Functor*
2352  function<_Res(_ArgTypes...)>::
2353  target() const noexcept
2354  {
2355  if (typeid(_Functor) == target_type() && _M_manager)
2356  {
2357  _Any_data __ptr;
2358  _M_manager(__ptr, _M_functor, __get_functor_ptr);
2359  return __ptr._M_access<const _Functor*>();
2360  }
2361  else
2362  return 0;
2363  }
2364 #endif
2365 
2366  // [20.7.15.2.6] null pointer comparisons
2367 
2368  /**
2369  * @brief Compares a polymorphic function object wrapper against 0
2370  * (the NULL pointer).
2371  * @returns @c true if the wrapper has no target, @c false otherwise
2372  *
2373  * This function will not throw an %exception.
2374  */
2375  template<typename _Res, typename... _Args>
2376  inline bool
2377  operator==(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
2378  { return !static_cast<bool>(__f); }
2379 
2380  /// @overload
2381  template<typename _Res, typename... _Args>
2382  inline bool
2383  operator==(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
2384  { return !static_cast<bool>(__f); }
2385 
2386  /**
2387  * @brief Compares a polymorphic function object wrapper against 0
2388  * (the NULL pointer).
2389  * @returns @c false if the wrapper has no target, @c true otherwise
2390  *
2391  * This function will not throw an %exception.
2392  */
2393  template<typename _Res, typename... _Args>
2394  inline bool
2395  operator!=(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
2396  { return static_cast<bool>(__f); }
2397 
2398  /// @overload
2399  template<typename _Res, typename... _Args>
2400  inline bool
2401  operator!=(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
2402  { return static_cast<bool>(__f); }
2403 
2404  // [20.7.15.2.7] specialized algorithms
2405 
2406  /**
2407  * @brief Swap the targets of two polymorphic function object wrappers.
2408  *
2409  * This function will not throw an %exception.
2410  */
2411  template<typename _Res, typename... _Args>
2412  inline void
2413  swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y)
2414  { __x.swap(__y); }
2415 
2416 _GLIBCXX_END_NAMESPACE_VERSION
2417 } // namespace std
2418 
2419 #endif // __GXX_EXPERIMENTAL_CXX0X__
2420 
2421 #endif // _GLIBCXX_FUNCTIONAL