libstdc++
functional
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00001 // <functional> -*- C++ -*-
00002 
00003 // Copyright (C) 2001-2013 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /*
00026  * Copyright (c) 1997
00027  * Silicon Graphics Computer Systems, Inc.
00028  *
00029  * Permission to use, copy, modify, distribute and sell this software
00030  * and its documentation for any purpose is hereby granted without fee,
00031  * provided that the above copyright notice appear in all copies and
00032  * that both that copyright notice and this permission notice appear
00033  * in supporting documentation.  Silicon Graphics makes no
00034  * representations about the suitability of this software for any
00035  * purpose.  It is provided "as is" without express or implied warranty.
00036  *
00037  */
00038 
00039 /** @file include/functional
00040  *  This is a Standard C++ Library header.
00041  */
00042 
00043 #ifndef _GLIBCXX_FUNCTIONAL
00044 #define _GLIBCXX_FUNCTIONAL 1
00045 
00046 #pragma GCC system_header
00047 
00048 #include <bits/c++config.h>
00049 #include <bits/stl_function.h>
00050 
00051 #if __cplusplus >= 201103L
00052 
00053 #include <typeinfo>
00054 #include <new>
00055 #include <tuple>
00056 #include <type_traits>
00057 #include <bits/functexcept.h>
00058 #include <bits/functional_hash.h>
00059 
00060 namespace std _GLIBCXX_VISIBILITY(default)
00061 {
00062 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00063 
00064   template<typename _MemberPointer>
00065     class _Mem_fn;
00066   template<typename _Tp, typename _Class>
00067     _Mem_fn<_Tp _Class::*>
00068     mem_fn(_Tp _Class::*) noexcept;
00069 
00070 _GLIBCXX_HAS_NESTED_TYPE(result_type)
00071 
00072   /// If we have found a result_type, extract it.
00073   template<bool _Has_result_type, typename _Functor>
00074     struct _Maybe_get_result_type
00075     { };
00076 
00077   template<typename _Functor>
00078     struct _Maybe_get_result_type<true, _Functor>
00079     { typedef typename _Functor::result_type result_type; };
00080 
00081   /**
00082    *  Base class for any function object that has a weak result type, as
00083    *  defined in 3.3/3 of TR1.
00084   */
00085   template<typename _Functor>
00086     struct _Weak_result_type_impl
00087     : _Maybe_get_result_type<__has_result_type<_Functor>::value, _Functor>
00088     { };
00089 
00090   /// Retrieve the result type for a function type.
00091   template<typename _Res, typename... _ArgTypes>
00092     struct _Weak_result_type_impl<_Res(_ArgTypes...)>
00093     { typedef _Res result_type; };
00094 
00095   template<typename _Res, typename... _ArgTypes>
00096     struct _Weak_result_type_impl<_Res(_ArgTypes......)>
00097     { typedef _Res result_type; };
00098 
00099   template<typename _Res, typename... _ArgTypes>
00100     struct _Weak_result_type_impl<_Res(_ArgTypes...) const>
00101     { typedef _Res result_type; };
00102 
00103   template<typename _Res, typename... _ArgTypes>
00104     struct _Weak_result_type_impl<_Res(_ArgTypes......) const>
00105     { typedef _Res result_type; };
00106 
00107   template<typename _Res, typename... _ArgTypes>
00108     struct _Weak_result_type_impl<_Res(_ArgTypes...) volatile>
00109     { typedef _Res result_type; };
00110 
00111   template<typename _Res, typename... _ArgTypes>
00112     struct _Weak_result_type_impl<_Res(_ArgTypes......) volatile>
00113     { typedef _Res result_type; };
00114 
00115   template<typename _Res, typename... _ArgTypes>
00116     struct _Weak_result_type_impl<_Res(_ArgTypes...) const volatile>
00117     { typedef _Res result_type; };
00118 
00119   template<typename _Res, typename... _ArgTypes>
00120     struct _Weak_result_type_impl<_Res(_ArgTypes......) const volatile>
00121     { typedef _Res result_type; };
00122 
00123   /// Retrieve the result type for a function reference.
00124   template<typename _Res, typename... _ArgTypes>
00125     struct _Weak_result_type_impl<_Res(&)(_ArgTypes...)>
00126     { typedef _Res result_type; };
00127 
00128   template<typename _Res, typename... _ArgTypes>
00129     struct _Weak_result_type_impl<_Res(&)(_ArgTypes......)>
00130     { typedef _Res result_type; };
00131 
00132   /// Retrieve the result type for a function pointer.
00133   template<typename _Res, typename... _ArgTypes>
00134     struct _Weak_result_type_impl<_Res(*)(_ArgTypes...)>
00135     { typedef _Res result_type; };
00136 
00137   template<typename _Res, typename... _ArgTypes>
00138     struct _Weak_result_type_impl<_Res(*)(_ArgTypes......)>
00139     { typedef _Res result_type; };
00140 
00141   /// Retrieve result type for a member function pointer.
00142   template<typename _Res, typename _Class, typename... _ArgTypes>
00143     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)>
00144     { typedef _Res result_type; };
00145 
00146   template<typename _Res, typename _Class, typename... _ArgTypes>
00147     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)>
00148     { typedef _Res result_type; };
00149 
00150   /// Retrieve result type for a const member function pointer.
00151   template<typename _Res, typename _Class, typename... _ArgTypes>
00152     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) const>
00153     { typedef _Res result_type; };
00154 
00155   template<typename _Res, typename _Class, typename... _ArgTypes>
00156     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) const>
00157     { typedef _Res result_type; };
00158 
00159   /// Retrieve result type for a volatile member function pointer.
00160   template<typename _Res, typename _Class, typename... _ArgTypes>
00161     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) volatile>
00162     { typedef _Res result_type; };
00163 
00164   template<typename _Res, typename _Class, typename... _ArgTypes>
00165     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) volatile>
00166     { typedef _Res result_type; };
00167 
00168   /// Retrieve result type for a const volatile member function pointer.
00169   template<typename _Res, typename _Class, typename... _ArgTypes>
00170     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)
00171                   const volatile>
00172     { typedef _Res result_type; };
00173 
00174   template<typename _Res, typename _Class, typename... _ArgTypes>
00175     struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)
00176                   const volatile>
00177     { typedef _Res result_type; };
00178 
00179   /**
00180    *  Strip top-level cv-qualifiers from the function object and let
00181    *  _Weak_result_type_impl perform the real work.
00182   */
00183   template<typename _Functor>
00184     struct _Weak_result_type
00185     : _Weak_result_type_impl<typename remove_cv<_Functor>::type>
00186     { };
00187 
00188   /// Determines if the type _Tp derives from unary_function.
00189   template<typename _Tp>
00190     struct _Derives_from_unary_function : __sfinae_types
00191     {
00192     private:
00193       template<typename _T1, typename _Res>
00194     static __one __test(const volatile unary_function<_T1, _Res>*);
00195 
00196       // It's tempting to change "..." to const volatile void*, but
00197       // that fails when _Tp is a function type.
00198       static __two __test(...);
00199 
00200     public:
00201       static const bool value = sizeof(__test((_Tp*)0)) == 1;
00202     };
00203 
00204   /// Determines if the type _Tp derives from binary_function.
00205   template<typename _Tp>
00206     struct _Derives_from_binary_function : __sfinae_types
00207     {
00208     private:
00209       template<typename _T1, typename _T2, typename _Res>
00210     static __one __test(const volatile binary_function<_T1, _T2, _Res>*);
00211 
00212       // It's tempting to change "..." to const volatile void*, but
00213       // that fails when _Tp is a function type.
00214       static __two __test(...);
00215 
00216     public:
00217       static const bool value = sizeof(__test((_Tp*)0)) == 1;
00218     };
00219 
00220   /**
00221    * Invoke a function object, which may be either a member pointer or a
00222    * function object. The first parameter will tell which.
00223    */
00224   template<typename _Functor, typename... _Args>
00225     inline
00226     typename enable_if<
00227          (!is_member_pointer<_Functor>::value
00228           && !is_function<_Functor>::value
00229           && !is_function<typename remove_pointer<_Functor>::type>::value),
00230          typename result_of<_Functor&(_Args&&...)>::type
00231        >::type
00232     __invoke(_Functor& __f, _Args&&... __args)
00233     {
00234       return __f(std::forward<_Args>(__args)...);
00235     }
00236 
00237   template<typename _Functor, typename... _Args>
00238     inline
00239     typename enable_if<
00240              (is_member_pointer<_Functor>::value
00241               && !is_function<_Functor>::value
00242               && !is_function<typename remove_pointer<_Functor>::type>::value),
00243              typename result_of<_Functor(_Args&&...)>::type
00244            >::type
00245     __invoke(_Functor& __f, _Args&&... __args)
00246     {
00247       return std::mem_fn(__f)(std::forward<_Args>(__args)...);
00248     }
00249 
00250   // To pick up function references (that will become function pointers)
00251   template<typename _Functor, typename... _Args>
00252     inline
00253     typename enable_if<
00254          (is_pointer<_Functor>::value
00255           && is_function<typename remove_pointer<_Functor>::type>::value),
00256          typename result_of<_Functor(_Args&&...)>::type
00257        >::type
00258     __invoke(_Functor __f, _Args&&... __args)
00259     {
00260       return __f(std::forward<_Args>(__args)...);
00261     }
00262 
00263   /**
00264    *  Knowing which of unary_function and binary_function _Tp derives
00265    *  from, derives from the same and ensures that reference_wrapper
00266    *  will have a weak result type. See cases below.
00267    */
00268   template<bool _Unary, bool _Binary, typename _Tp>
00269     struct _Reference_wrapper_base_impl;
00270 
00271   // None of the nested argument types.
00272   template<typename _Tp>
00273     struct _Reference_wrapper_base_impl<false, false, _Tp>
00274     : _Weak_result_type<_Tp>
00275     { };
00276 
00277   // Nested argument_type only.
00278   template<typename _Tp>
00279     struct _Reference_wrapper_base_impl<true, false, _Tp>
00280     : _Weak_result_type<_Tp>
00281     {
00282       typedef typename _Tp::argument_type argument_type;
00283     };
00284 
00285   // Nested first_argument_type and second_argument_type only.
00286   template<typename _Tp>
00287     struct _Reference_wrapper_base_impl<false, true, _Tp>
00288     : _Weak_result_type<_Tp>
00289     {
00290       typedef typename _Tp::first_argument_type first_argument_type;
00291       typedef typename _Tp::second_argument_type second_argument_type;
00292     };
00293 
00294   // All the nested argument types.
00295    template<typename _Tp>
00296     struct _Reference_wrapper_base_impl<true, true, _Tp>
00297     : _Weak_result_type<_Tp>
00298     {
00299       typedef typename _Tp::argument_type argument_type;
00300       typedef typename _Tp::first_argument_type first_argument_type;
00301       typedef typename _Tp::second_argument_type second_argument_type;
00302     };
00303 
00304   _GLIBCXX_HAS_NESTED_TYPE(argument_type)
00305   _GLIBCXX_HAS_NESTED_TYPE(first_argument_type)
00306   _GLIBCXX_HAS_NESTED_TYPE(second_argument_type)
00307 
00308   /**
00309    *  Derives from unary_function or binary_function when it
00310    *  can. Specializations handle all of the easy cases. The primary
00311    *  template determines what to do with a class type, which may
00312    *  derive from both unary_function and binary_function.
00313   */
00314   template<typename _Tp>
00315     struct _Reference_wrapper_base
00316     : _Reference_wrapper_base_impl<
00317       __has_argument_type<_Tp>::value,
00318       __has_first_argument_type<_Tp>::value
00319       && __has_second_argument_type<_Tp>::value,
00320       _Tp>
00321     { };
00322 
00323   // - a function type (unary)
00324   template<typename _Res, typename _T1>
00325     struct _Reference_wrapper_base<_Res(_T1)>
00326     : unary_function<_T1, _Res>
00327     { };
00328 
00329   template<typename _Res, typename _T1>
00330     struct _Reference_wrapper_base<_Res(_T1) const>
00331     : unary_function<_T1, _Res>
00332     { };
00333 
00334   template<typename _Res, typename _T1>
00335     struct _Reference_wrapper_base<_Res(_T1) volatile>
00336     : unary_function<_T1, _Res>
00337     { };
00338 
00339   template<typename _Res, typename _T1>
00340     struct _Reference_wrapper_base<_Res(_T1) const volatile>
00341     : unary_function<_T1, _Res>
00342     { };
00343 
00344   // - a function type (binary)
00345   template<typename _Res, typename _T1, typename _T2>
00346     struct _Reference_wrapper_base<_Res(_T1, _T2)>
00347     : binary_function<_T1, _T2, _Res>
00348     { };
00349 
00350   template<typename _Res, typename _T1, typename _T2>
00351     struct _Reference_wrapper_base<_Res(_T1, _T2) const>
00352     : binary_function<_T1, _T2, _Res>
00353     { };
00354 
00355   template<typename _Res, typename _T1, typename _T2>
00356     struct _Reference_wrapper_base<_Res(_T1, _T2) volatile>
00357     : binary_function<_T1, _T2, _Res>
00358     { };
00359 
00360   template<typename _Res, typename _T1, typename _T2>
00361     struct _Reference_wrapper_base<_Res(_T1, _T2) const volatile>
00362     : binary_function<_T1, _T2, _Res>
00363     { };
00364 
00365   // - a function pointer type (unary)
00366   template<typename _Res, typename _T1>
00367     struct _Reference_wrapper_base<_Res(*)(_T1)>
00368     : unary_function<_T1, _Res>
00369     { };
00370 
00371   // - a function pointer type (binary)
00372   template<typename _Res, typename _T1, typename _T2>
00373     struct _Reference_wrapper_base<_Res(*)(_T1, _T2)>
00374     : binary_function<_T1, _T2, _Res>
00375     { };
00376 
00377   // - a pointer to member function type (unary, no qualifiers)
00378   template<typename _Res, typename _T1>
00379     struct _Reference_wrapper_base<_Res (_T1::*)()>
00380     : unary_function<_T1*, _Res>
00381     { };
00382 
00383   // - a pointer to member function type (binary, no qualifiers)
00384   template<typename _Res, typename _T1, typename _T2>
00385     struct _Reference_wrapper_base<_Res (_T1::*)(_T2)>
00386     : binary_function<_T1*, _T2, _Res>
00387     { };
00388 
00389   // - a pointer to member function type (unary, const)
00390   template<typename _Res, typename _T1>
00391     struct _Reference_wrapper_base<_Res (_T1::*)() const>
00392     : unary_function<const _T1*, _Res>
00393     { };
00394 
00395   // - a pointer to member function type (binary, const)
00396   template<typename _Res, typename _T1, typename _T2>
00397     struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const>
00398     : binary_function<const _T1*, _T2, _Res>
00399     { };
00400 
00401   // - a pointer to member function type (unary, volatile)
00402   template<typename _Res, typename _T1>
00403     struct _Reference_wrapper_base<_Res (_T1::*)() volatile>
00404     : unary_function<volatile _T1*, _Res>
00405     { };
00406 
00407   // - a pointer to member function type (binary, volatile)
00408   template<typename _Res, typename _T1, typename _T2>
00409     struct _Reference_wrapper_base<_Res (_T1::*)(_T2) volatile>
00410     : binary_function<volatile _T1*, _T2, _Res>
00411     { };
00412 
00413   // - a pointer to member function type (unary, const volatile)
00414   template<typename _Res, typename _T1>
00415     struct _Reference_wrapper_base<_Res (_T1::*)() const volatile>
00416     : unary_function<const volatile _T1*, _Res>
00417     { };
00418 
00419   // - a pointer to member function type (binary, const volatile)
00420   template<typename _Res, typename _T1, typename _T2>
00421     struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const volatile>
00422     : binary_function<const volatile _T1*, _T2, _Res>
00423     { };
00424 
00425   /**
00426    *  @brief Primary class template for reference_wrapper.
00427    *  @ingroup functors
00428    *  @{
00429    */
00430   template<typename _Tp>
00431     class reference_wrapper
00432     : public _Reference_wrapper_base<typename remove_cv<_Tp>::type>
00433     {
00434       _Tp* _M_data;
00435 
00436     public:
00437       typedef _Tp type;
00438 
00439       reference_wrapper(_Tp& __indata) noexcept
00440       : _M_data(std::__addressof(__indata))
00441       { }
00442 
00443       reference_wrapper(_Tp&&) = delete;
00444 
00445       reference_wrapper(const reference_wrapper<_Tp>& __inref) noexcept
00446       : _M_data(__inref._M_data)
00447       { }
00448 
00449       reference_wrapper&
00450       operator=(const reference_wrapper<_Tp>& __inref) noexcept
00451       {
00452     _M_data = __inref._M_data;
00453     return *this;
00454       }
00455 
00456       operator _Tp&() const noexcept
00457       { return this->get(); }
00458 
00459       _Tp&
00460       get() const noexcept
00461       { return *_M_data; }
00462 
00463       template<typename... _Args>
00464     typename result_of<_Tp&(_Args&&...)>::type
00465     operator()(_Args&&... __args) const
00466     {
00467       return __invoke(get(), std::forward<_Args>(__args)...);
00468     }
00469     };
00470 
00471 
00472   /// Denotes a reference should be taken to a variable.
00473   template<typename _Tp>
00474     inline reference_wrapper<_Tp>
00475     ref(_Tp& __t) noexcept
00476     { return reference_wrapper<_Tp>(__t); }
00477 
00478   /// Denotes a const reference should be taken to a variable.
00479   template<typename _Tp>
00480     inline reference_wrapper<const _Tp>
00481     cref(const _Tp& __t) noexcept
00482     { return reference_wrapper<const _Tp>(__t); }
00483 
00484   template<typename _Tp>
00485     void ref(const _Tp&&) = delete;
00486 
00487   template<typename _Tp>
00488     void cref(const _Tp&&) = delete;
00489 
00490   /// Partial specialization.
00491   template<typename _Tp>
00492     inline reference_wrapper<_Tp>
00493     ref(reference_wrapper<_Tp> __t) noexcept
00494     { return ref(__t.get()); }
00495 
00496   /// Partial specialization.
00497   template<typename _Tp>
00498     inline reference_wrapper<const _Tp>
00499     cref(reference_wrapper<_Tp> __t) noexcept
00500     { return cref(__t.get()); }
00501 
00502   // @} group functors
00503 
00504   template<typename... _Types>
00505     struct _Pack : integral_constant<size_t, sizeof...(_Types)>
00506     { };
00507 
00508   template<typename _From, typename _To, bool = _From::value == _To::value>
00509     struct _AllConvertible : false_type
00510     { };
00511 
00512   template<typename... _From, typename... _To>
00513     struct _AllConvertible<_Pack<_From...>, _Pack<_To...>, true>
00514     : __and_<is_convertible<_From, _To>...>
00515     { };
00516 
00517   template<typename _Tp1, typename _Tp2>
00518     using _NotSame = __not_<is_same<typename std::decay<_Tp1>::type,
00519                     typename std::decay<_Tp2>::type>>;
00520 
00521   /**
00522    * Derives from @c unary_function or @c binary_function, or perhaps
00523    * nothing, depending on the number of arguments provided. The
00524    * primary template is the basis case, which derives nothing.
00525    */
00526   template<typename _Res, typename... _ArgTypes>
00527     struct _Maybe_unary_or_binary_function { };
00528 
00529   /// Derives from @c unary_function, as appropriate.
00530   template<typename _Res, typename _T1>
00531     struct _Maybe_unary_or_binary_function<_Res, _T1>
00532     : std::unary_function<_T1, _Res> { };
00533 
00534   /// Derives from @c binary_function, as appropriate.
00535   template<typename _Res, typename _T1, typename _T2>
00536     struct _Maybe_unary_or_binary_function<_Res, _T1, _T2>
00537     : std::binary_function<_T1, _T2, _Res> { };
00538 
00539   /// Implementation of @c mem_fn for member function pointers.
00540   template<typename _Res, typename _Class, typename... _ArgTypes>
00541     class _Mem_fn<_Res (_Class::*)(_ArgTypes...)>
00542     : public _Maybe_unary_or_binary_function<_Res, _Class*, _ArgTypes...>
00543     {
00544       typedef _Res (_Class::*_Functor)(_ArgTypes...);
00545 
00546       template<typename _Tp, typename... _Args>
00547     _Res
00548     _M_call(_Tp&& __object, const volatile _Class *,
00549         _Args&&... __args) const
00550     {
00551       return (std::forward<_Tp>(__object).*__pmf)
00552         (std::forward<_Args>(__args)...);
00553     }
00554 
00555       template<typename _Tp, typename... _Args>
00556     _Res
00557     _M_call(_Tp&& __ptr, const volatile void *, _Args&&... __args) const
00558     { return ((*__ptr).*__pmf)(std::forward<_Args>(__args)...); }
00559 
00560       // Require each _Args to be convertible to corresponding _ArgTypes
00561       template<typename... _Args>
00562     using _RequireValidArgs
00563       = _Require<_AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00564 
00565       // Require each _Args to be convertible to corresponding _ArgTypes
00566       // and require _Tp is not _Class, _Class& or _Class*
00567       template<typename _Tp, typename... _Args>
00568     using _RequireValidArgs2
00569       = _Require<_NotSame<_Class, _Tp>, _NotSame<_Class*, _Tp>,
00570              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00571 
00572       // Require each _Args to be convertible to corresponding _ArgTypes
00573       // and require _Tp is _Class or derived from _Class
00574       template<typename _Tp, typename... _Args>
00575     using _RequireValidArgs3
00576       = _Require<is_base_of<_Class, _Tp>,
00577              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00578 
00579     public:
00580       typedef _Res result_type;
00581 
00582       explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
00583 
00584       // Handle objects
00585       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00586     _Res
00587     operator()(_Class& __object, _Args&&... __args) const
00588     { return (__object.*__pmf)(std::forward<_Args>(__args)...); }
00589 
00590       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00591     _Res
00592     operator()(_Class&& __object, _Args&&... __args) const
00593     {
00594       return (std::move(__object).*__pmf)(std::forward<_Args>(__args)...);
00595     }
00596 
00597       // Handle pointers
00598       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00599     _Res
00600     operator()(_Class* __object, _Args&&... __args) const
00601     { return (__object->*__pmf)(std::forward<_Args>(__args)...); }
00602 
00603       // Handle smart pointers, references and pointers to derived
00604       template<typename _Tp, typename... _Args,
00605            typename _Req = _RequireValidArgs2<_Tp, _Args...>>
00606     _Res
00607     operator()(_Tp&& __object, _Args&&... __args) const
00608     {
00609       return _M_call(std::forward<_Tp>(__object), &__object,
00610           std::forward<_Args>(__args)...);
00611     }
00612 
00613       template<typename _Tp, typename... _Args,
00614            typename _Req = _RequireValidArgs3<_Tp, _Args...>>
00615     _Res
00616     operator()(reference_wrapper<_Tp> __ref, _Args&&... __args) const
00617     { return operator()(__ref.get(), std::forward<_Args>(__args)...); }
00618 
00619     private:
00620       _Functor __pmf;
00621     };
00622 
00623   /// Implementation of @c mem_fn for const member function pointers.
00624   template<typename _Res, typename _Class, typename... _ArgTypes>
00625     class _Mem_fn<_Res (_Class::*)(_ArgTypes...) const>
00626     : public _Maybe_unary_or_binary_function<_Res, const _Class*,
00627                          _ArgTypes...>
00628     {
00629       typedef _Res (_Class::*_Functor)(_ArgTypes...) const;
00630 
00631       template<typename _Tp, typename... _Args>
00632     _Res
00633     _M_call(_Tp&& __object, const volatile _Class *,
00634         _Args&&... __args) const
00635     {
00636       return (std::forward<_Tp>(__object).*__pmf)
00637         (std::forward<_Args>(__args)...);
00638     }
00639 
00640       template<typename _Tp, typename... _Args>
00641     _Res
00642     _M_call(_Tp&& __ptr, const volatile void *, _Args&&... __args) const
00643     { return ((*__ptr).*__pmf)(std::forward<_Args>(__args)...); }
00644 
00645       template<typename... _Args>
00646     using _RequireValidArgs
00647       = _Require<_AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00648 
00649       template<typename _Tp, typename... _Args>
00650     using _RequireValidArgs2
00651       = _Require<_NotSame<_Class, _Tp>, _NotSame<const _Class*, _Tp>,
00652              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00653 
00654       template<typename _Tp, typename... _Args>
00655     using _RequireValidArgs3
00656       = _Require<is_base_of<_Class, _Tp>,
00657              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00658 
00659     public:
00660       typedef _Res result_type;
00661 
00662       explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
00663 
00664       // Handle objects
00665       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00666     _Res
00667     operator()(const _Class& __object, _Args&&... __args) const
00668     { return (__object.*__pmf)(std::forward<_Args>(__args)...); }
00669 
00670       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00671     _Res
00672     operator()(const _Class&& __object, _Args&&... __args) const
00673     {
00674       return (std::move(__object).*__pmf)(std::forward<_Args>(__args)...);
00675     }
00676 
00677       // Handle pointers
00678       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00679     _Res
00680     operator()(const _Class* __object, _Args&&... __args) const
00681     { return (__object->*__pmf)(std::forward<_Args>(__args)...); }
00682 
00683       // Handle smart pointers, references and pointers to derived
00684       template<typename _Tp, typename... _Args,
00685            typename _Req = _RequireValidArgs2<_Tp, _Args...>>
00686     _Res operator()(_Tp&& __object, _Args&&... __args) const
00687     {
00688       return _M_call(std::forward<_Tp>(__object), &__object,
00689           std::forward<_Args>(__args)...);
00690     }
00691 
00692       template<typename _Tp, typename... _Args,
00693            typename _Req = _RequireValidArgs3<_Tp, _Args...>>
00694     _Res
00695     operator()(reference_wrapper<_Tp> __ref, _Args&&... __args) const
00696     { return operator()(__ref.get(), std::forward<_Args>(__args)...); }
00697 
00698     private:
00699       _Functor __pmf;
00700     };
00701 
00702   /// Implementation of @c mem_fn for volatile member function pointers.
00703   template<typename _Res, typename _Class, typename... _ArgTypes>
00704     class _Mem_fn<_Res (_Class::*)(_ArgTypes...) volatile>
00705     : public _Maybe_unary_or_binary_function<_Res, volatile _Class*,
00706                          _ArgTypes...>
00707     {
00708       typedef _Res (_Class::*_Functor)(_ArgTypes...) volatile;
00709 
00710       template<typename _Tp, typename... _Args>
00711     _Res
00712     _M_call(_Tp&& __object, const volatile _Class *,
00713         _Args&&... __args) const
00714     {
00715       return (std::forward<_Tp>(__object).*__pmf)
00716         (std::forward<_Args>(__args)...);
00717     }
00718 
00719       template<typename _Tp, typename... _Args>
00720     _Res
00721     _M_call(_Tp&& __ptr, const volatile void *, _Args&&... __args) const
00722     { return ((*__ptr).*__pmf)(std::forward<_Args>(__args)...); }
00723 
00724       template<typename... _Args>
00725     using _RequireValidArgs
00726       = _Require<_AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00727 
00728       template<typename _Tp, typename... _Args>
00729     using _RequireValidArgs2
00730       = _Require<_NotSame<_Class, _Tp>, _NotSame<volatile _Class*, _Tp>,
00731              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00732 
00733       template<typename _Tp, typename... _Args>
00734     using _RequireValidArgs3
00735       = _Require<is_base_of<_Class, _Tp>,
00736              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00737 
00738     public:
00739       typedef _Res result_type;
00740 
00741       explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
00742 
00743       // Handle objects
00744       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00745     _Res
00746     operator()(volatile _Class& __object, _Args&&... __args) const
00747     { return (__object.*__pmf)(std::forward<_Args>(__args)...); }
00748 
00749       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00750     _Res
00751     operator()(volatile _Class&& __object, _Args&&... __args) const
00752     {
00753       return (std::move(__object).*__pmf)(std::forward<_Args>(__args)...);
00754     }
00755 
00756       // Handle pointers
00757       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00758     _Res
00759     operator()(volatile _Class* __object, _Args&&... __args) const
00760     { return (__object->*__pmf)(std::forward<_Args>(__args)...); }
00761 
00762       // Handle smart pointers, references and pointers to derived
00763       template<typename _Tp, typename... _Args,
00764            typename _Req = _RequireValidArgs2<_Tp, _Args...>>
00765     _Res
00766     operator()(_Tp&& __object, _Args&&... __args) const
00767     {
00768       return _M_call(std::forward<_Tp>(__object), &__object,
00769           std::forward<_Args>(__args)...);
00770     }
00771 
00772       template<typename _Tp, typename... _Args,
00773            typename _Req = _RequireValidArgs3<_Tp, _Args...>>
00774     _Res
00775     operator()(reference_wrapper<_Tp> __ref, _Args&&... __args) const
00776     { return operator()(__ref.get(), std::forward<_Args>(__args)...); }
00777 
00778     private:
00779       _Functor __pmf;
00780     };
00781 
00782   /// Implementation of @c mem_fn for const volatile member function pointers.
00783   template<typename _Res, typename _Class, typename... _ArgTypes>
00784     class _Mem_fn<_Res (_Class::*)(_ArgTypes...) const volatile>
00785     : public _Maybe_unary_or_binary_function<_Res, const volatile _Class*,
00786                          _ArgTypes...>
00787     {
00788       typedef _Res (_Class::*_Functor)(_ArgTypes...) const volatile;
00789 
00790       template<typename _Tp, typename... _Args>
00791     _Res
00792     _M_call(_Tp&& __object, const volatile _Class *,
00793         _Args&&... __args) const
00794     {
00795       return (std::forward<_Tp>(__object).*__pmf)
00796         (std::forward<_Args>(__args)...);
00797     }
00798 
00799       template<typename _Tp, typename... _Args>
00800     _Res
00801     _M_call(_Tp&& __ptr, const volatile void *, _Args&&... __args) const
00802     { return ((*__ptr).*__pmf)(std::forward<_Args>(__args)...); }
00803 
00804       template<typename... _Args>
00805     using _RequireValidArgs
00806       = _Require<_AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00807 
00808       template<typename _Tp, typename... _Args>
00809     using _RequireValidArgs2
00810       = _Require<_NotSame<_Class, _Tp>,
00811              _NotSame<const volatile _Class*, _Tp>,
00812              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00813 
00814       template<typename _Tp, typename... _Args>
00815     using _RequireValidArgs3
00816       = _Require<is_base_of<_Class, _Tp>,
00817              _AllConvertible<_Pack<_Args...>, _Pack<_ArgTypes...>>>;
00818 
00819     public:
00820       typedef _Res result_type;
00821 
00822       explicit _Mem_fn(_Functor __pmf) : __pmf(__pmf) { }
00823 
00824       // Handle objects
00825       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00826     _Res
00827     operator()(const volatile _Class& __object, _Args&&... __args) const
00828     { return (__object.*__pmf)(std::forward<_Args>(__args)...); }
00829 
00830       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00831     _Res
00832     operator()(const volatile _Class&& __object, _Args&&... __args) const
00833     {
00834       return (std::move(__object).*__pmf)(std::forward<_Args>(__args)...);
00835     }
00836 
00837       // Handle pointers
00838       template<typename... _Args, typename _Req = _RequireValidArgs<_Args...>>
00839     _Res
00840     operator()(const volatile _Class* __object, _Args&&... __args) const
00841     { return (__object->*__pmf)(std::forward<_Args>(__args)...); }
00842 
00843       // Handle smart pointers, references and pointers to derived
00844       template<typename _Tp, typename... _Args,
00845            typename _Req = _RequireValidArgs2<_Tp, _Args...>>
00846     _Res operator()(_Tp&& __object, _Args&&... __args) const
00847     {
00848       return _M_call(std::forward<_Tp>(__object), &__object,
00849           std::forward<_Args>(__args)...);
00850     }
00851 
00852       template<typename _Tp, typename... _Args,
00853            typename _Req = _RequireValidArgs3<_Tp, _Args...>>
00854     _Res
00855     operator()(reference_wrapper<_Tp> __ref, _Args&&... __args) const
00856     { return operator()(__ref.get(), std::forward<_Args>(__args)...); }
00857 
00858     private:
00859       _Functor __pmf;
00860     };
00861 
00862 
00863   template<typename _Tp, bool>
00864     struct _Mem_fn_const_or_non
00865     {
00866       typedef const _Tp& type;
00867     };
00868 
00869   template<typename _Tp>
00870     struct _Mem_fn_const_or_non<_Tp, false>
00871     {
00872       typedef _Tp& type;
00873     };
00874 
00875   template<typename _Res, typename _Class>
00876     class _Mem_fn<_Res _Class::*>
00877     {
00878       using __pm_type = _Res _Class::*;
00879 
00880       // This bit of genius is due to Peter Dimov, improved slightly by
00881       // Douglas Gregor.
00882       // Made less elegant to support perfect forwarding and noexcept.
00883       template<typename _Tp>
00884     auto
00885     _M_call(_Tp&& __object, const _Class *) const noexcept
00886     -> decltype(std::forward<_Tp>(__object).*std::declval<__pm_type&>())
00887     { return std::forward<_Tp>(__object).*__pm; }
00888 
00889       template<typename _Tp, typename _Up>
00890     auto
00891     _M_call(_Tp&& __object, _Up * const *) const noexcept
00892     -> decltype((*std::forward<_Tp>(__object)).*std::declval<__pm_type&>())
00893     { return (*std::forward<_Tp>(__object)).*__pm; }
00894 
00895       template<typename _Tp>
00896     auto
00897     _M_call(_Tp&& __ptr, const volatile void*) const
00898     noexcept(noexcept((*__ptr).*std::declval<__pm_type&>()))
00899     -> decltype((*__ptr).*std::declval<__pm_type&>())
00900     { return (*__ptr).*__pm; }
00901 
00902     public:
00903       explicit
00904       _Mem_fn(_Res _Class::*__pm) noexcept : __pm(__pm) { }
00905 
00906       // Handle objects
00907       _Res&
00908       operator()(_Class& __object) const noexcept
00909       { return __object.*__pm; }
00910 
00911       const _Res&
00912       operator()(const _Class& __object) const noexcept
00913       { return __object.*__pm; }
00914 
00915       _Res&&
00916       operator()(_Class&& __object) const noexcept
00917       { return std::forward<_Class>(__object).*__pm; }
00918 
00919       const _Res&&
00920       operator()(const _Class&& __object) const noexcept
00921       { return std::forward<const _Class>(__object).*__pm; }
00922 
00923       // Handle pointers
00924       _Res&
00925       operator()(_Class* __object) const noexcept
00926       { return __object->*__pm; }
00927 
00928       const _Res&
00929       operator()(const _Class* __object) const noexcept
00930       { return __object->*__pm; }
00931 
00932       // Handle smart pointers and derived
00933       template<typename _Tp, typename _Req = _Require<_NotSame<_Class*, _Tp>>>
00934     auto
00935     operator()(_Tp&& __unknown) const
00936     noexcept(noexcept(std::declval<_Mem_fn*>()->_M_call
00937               (std::forward<_Tp>(__unknown), &__unknown)))
00938     -> decltype(this->_M_call(std::forward<_Tp>(__unknown), &__unknown))
00939     { return _M_call(std::forward<_Tp>(__unknown), &__unknown); }
00940 
00941       template<typename _Tp, typename _Req = _Require<is_base_of<_Class, _Tp>>>
00942     auto
00943     operator()(reference_wrapper<_Tp> __ref) const
00944     noexcept(noexcept(std::declval<_Mem_fn&>()(__ref.get())))
00945     -> decltype((*this)(__ref.get()))
00946     { return (*this)(__ref.get()); }
00947 
00948     private:
00949       _Res _Class::*__pm;
00950     };
00951 
00952   // _GLIBCXX_RESOLVE_LIB_DEFECTS
00953   // 2048.  Unnecessary mem_fn overloads
00954   /**
00955    *  @brief Returns a function object that forwards to the member
00956    *  pointer @a pm.
00957    *  @ingroup functors
00958    */
00959   template<typename _Tp, typename _Class>
00960     inline _Mem_fn<_Tp _Class::*>
00961     mem_fn(_Tp _Class::* __pm) noexcept
00962     {
00963       return _Mem_fn<_Tp _Class::*>(__pm);
00964     }
00965 
00966   /**
00967    *  @brief Determines if the given type _Tp is a function object
00968    *  should be treated as a subexpression when evaluating calls to
00969    *  function objects returned by bind(). [TR1 3.6.1]
00970    *  @ingroup binders
00971    */
00972   template<typename _Tp>
00973     struct is_bind_expression
00974     : public false_type { };
00975 
00976   /**
00977    *  @brief Determines if the given type _Tp is a placeholder in a
00978    *  bind() expression and, if so, which placeholder it is. [TR1 3.6.2]
00979    *  @ingroup binders
00980    */
00981   template<typename _Tp>
00982     struct is_placeholder
00983     : public integral_constant<int, 0>
00984     { };
00985 
00986   /** @brief The type of placeholder objects defined by libstdc++.
00987    *  @ingroup binders
00988    */
00989   template<int _Num> struct _Placeholder { };
00990 
00991   _GLIBCXX_END_NAMESPACE_VERSION
00992 
00993   /** @namespace std::placeholders
00994    *  @brief ISO C++11 entities sub-namespace for functional.
00995    *  @ingroup binders
00996    */
00997   namespace placeholders
00998   {
00999   _GLIBCXX_BEGIN_NAMESPACE_VERSION
01000   /* Define a large number of placeholders. There is no way to
01001    * simplify this with variadic templates, because we're introducing
01002    * unique names for each.
01003    */
01004     extern const _Placeholder<1> _1;
01005     extern const _Placeholder<2> _2;
01006     extern const _Placeholder<3> _3;
01007     extern const _Placeholder<4> _4;
01008     extern const _Placeholder<5> _5;
01009     extern const _Placeholder<6> _6;
01010     extern const _Placeholder<7> _7;
01011     extern const _Placeholder<8> _8;
01012     extern const _Placeholder<9> _9;
01013     extern const _Placeholder<10> _10;
01014     extern const _Placeholder<11> _11;
01015     extern const _Placeholder<12> _12;
01016     extern const _Placeholder<13> _13;
01017     extern const _Placeholder<14> _14;
01018     extern const _Placeholder<15> _15;
01019     extern const _Placeholder<16> _16;
01020     extern const _Placeholder<17> _17;
01021     extern const _Placeholder<18> _18;
01022     extern const _Placeholder<19> _19;
01023     extern const _Placeholder<20> _20;
01024     extern const _Placeholder<21> _21;
01025     extern const _Placeholder<22> _22;
01026     extern const _Placeholder<23> _23;
01027     extern const _Placeholder<24> _24;
01028     extern const _Placeholder<25> _25;
01029     extern const _Placeholder<26> _26;
01030     extern const _Placeholder<27> _27;
01031     extern const _Placeholder<28> _28;
01032     extern const _Placeholder<29> _29;
01033   _GLIBCXX_END_NAMESPACE_VERSION
01034   }
01035 
01036   _GLIBCXX_BEGIN_NAMESPACE_VERSION
01037 
01038   /**
01039    *  Partial specialization of is_placeholder that provides the placeholder
01040    *  number for the placeholder objects defined by libstdc++.
01041    *  @ingroup binders
01042    */
01043   template<int _Num>
01044     struct is_placeholder<_Placeholder<_Num> >
01045     : public integral_constant<int, _Num>
01046     { };
01047 
01048   template<int _Num>
01049     struct is_placeholder<const _Placeholder<_Num> >
01050     : public integral_constant<int, _Num>
01051     { };
01052 
01053   /**
01054    * Used by _Safe_tuple_element to indicate that there is no tuple
01055    * element at this position.
01056    */
01057   struct _No_tuple_element;
01058 
01059   /**
01060    * Implementation helper for _Safe_tuple_element. This primary
01061    * template handles the case where it is safe to use @c
01062    * tuple_element.
01063    */
01064   template<std::size_t __i, typename _Tuple, bool _IsSafe>
01065     struct _Safe_tuple_element_impl
01066     : tuple_element<__i, _Tuple> { };
01067 
01068   /**
01069    * Implementation helper for _Safe_tuple_element. This partial
01070    * specialization handles the case where it is not safe to use @c
01071    * tuple_element. We just return @c _No_tuple_element.
01072    */
01073   template<std::size_t __i, typename _Tuple>
01074     struct _Safe_tuple_element_impl<__i, _Tuple, false>
01075     {
01076       typedef _No_tuple_element type;
01077     };
01078 
01079   /**
01080    * Like tuple_element, but returns @c _No_tuple_element when
01081    * tuple_element would return an error.
01082    */
01083  template<std::size_t __i, typename _Tuple>
01084    struct _Safe_tuple_element
01085    : _Safe_tuple_element_impl<__i, _Tuple,
01086                   (__i < tuple_size<_Tuple>::value)>
01087    { };
01088 
01089   /**
01090    *  Maps an argument to bind() into an actual argument to the bound
01091    *  function object [TR1 3.6.3/5]. Only the first parameter should
01092    *  be specified: the rest are used to determine among the various
01093    *  implementations. Note that, although this class is a function
01094    *  object, it isn't entirely normal because it takes only two
01095    *  parameters regardless of the number of parameters passed to the
01096    *  bind expression. The first parameter is the bound argument and
01097    *  the second parameter is a tuple containing references to the
01098    *  rest of the arguments.
01099    */
01100   template<typename _Arg,
01101        bool _IsBindExp = is_bind_expression<_Arg>::value,
01102        bool _IsPlaceholder = (is_placeholder<_Arg>::value > 0)>
01103     class _Mu;
01104 
01105   /**
01106    *  If the argument is reference_wrapper<_Tp>, returns the
01107    *  underlying reference. [TR1 3.6.3/5 bullet 1]
01108    */
01109   template<typename _Tp>
01110     class _Mu<reference_wrapper<_Tp>, false, false>
01111     {
01112     public:
01113       typedef _Tp& result_type;
01114 
01115       /* Note: This won't actually work for const volatile
01116        * reference_wrappers, because reference_wrapper::get() is const
01117        * but not volatile-qualified. This might be a defect in the TR.
01118        */
01119       template<typename _CVRef, typename _Tuple>
01120     result_type
01121     operator()(_CVRef& __arg, _Tuple&) const volatile
01122     { return __arg.get(); }
01123     };
01124 
01125   /**
01126    *  If the argument is a bind expression, we invoke the underlying
01127    *  function object with the same cv-qualifiers as we are given and
01128    *  pass along all of our arguments (unwrapped). [TR1 3.6.3/5 bullet 2]
01129    */
01130   template<typename _Arg>
01131     class _Mu<_Arg, true, false>
01132     {
01133     public:
01134       template<typename _CVArg, typename... _Args>
01135     auto
01136     operator()(_CVArg& __arg,
01137            tuple<_Args...>& __tuple) const volatile
01138     -> decltype(__arg(declval<_Args>()...))
01139     {
01140       // Construct an index tuple and forward to __call
01141       typedef typename _Build_index_tuple<sizeof...(_Args)>::__type
01142         _Indexes;
01143       return this->__call(__arg, __tuple, _Indexes());
01144     }
01145 
01146     private:
01147       // Invokes the underlying function object __arg by unpacking all
01148       // of the arguments in the tuple.
01149       template<typename _CVArg, typename... _Args, std::size_t... _Indexes>
01150     auto
01151     __call(_CVArg& __arg, tuple<_Args...>& __tuple,
01152            const _Index_tuple<_Indexes...>&) const volatile
01153     -> decltype(__arg(declval<_Args>()...))
01154     {
01155       return __arg(std::forward<_Args>(get<_Indexes>(__tuple))...);
01156     }
01157     };
01158 
01159   /**
01160    *  If the argument is a placeholder for the Nth argument, returns
01161    *  a reference to the Nth argument to the bind function object.
01162    *  [TR1 3.6.3/5 bullet 3]
01163    */
01164   template<typename _Arg>
01165     class _Mu<_Arg, false, true>
01166     {
01167     public:
01168       template<typename _Signature> class result;
01169 
01170       template<typename _CVMu, typename _CVArg, typename _Tuple>
01171     class result<_CVMu(_CVArg, _Tuple)>
01172     {
01173       // Add a reference, if it hasn't already been done for us.
01174       // This allows us to be a little bit sloppy in constructing
01175       // the tuple that we pass to result_of<...>.
01176       typedef typename _Safe_tuple_element<(is_placeholder<_Arg>::value
01177                         - 1), _Tuple>::type
01178         __base_type;
01179 
01180     public:
01181       typedef typename add_rvalue_reference<__base_type>::type type;
01182     };
01183 
01184       template<typename _Tuple>
01185     typename result<_Mu(_Arg, _Tuple)>::type
01186     operator()(const volatile _Arg&, _Tuple& __tuple) const volatile
01187     {
01188       return std::forward<typename result<_Mu(_Arg, _Tuple)>::type>(
01189           ::std::get<(is_placeholder<_Arg>::value - 1)>(__tuple));
01190     }
01191     };
01192 
01193   /**
01194    *  If the argument is just a value, returns a reference to that
01195    *  value. The cv-qualifiers on the reference are the same as the
01196    *  cv-qualifiers on the _Mu object. [TR1 3.6.3/5 bullet 4]
01197    */
01198   template<typename _Arg>
01199     class _Mu<_Arg, false, false>
01200     {
01201     public:
01202       template<typename _Signature> struct result;
01203 
01204       template<typename _CVMu, typename _CVArg, typename _Tuple>
01205     struct result<_CVMu(_CVArg, _Tuple)>
01206     {
01207       typedef typename add_lvalue_reference<_CVArg>::type type;
01208     };
01209 
01210       // Pick up the cv-qualifiers of the argument
01211       template<typename _CVArg, typename _Tuple>
01212     _CVArg&&
01213     operator()(_CVArg&& __arg, _Tuple&) const volatile
01214     { return std::forward<_CVArg>(__arg); }
01215     };
01216 
01217   /**
01218    *  Maps member pointers into instances of _Mem_fn but leaves all
01219    *  other function objects untouched. Used by tr1::bind(). The
01220    *  primary template handles the non--member-pointer case.
01221    */
01222   template<typename _Tp>
01223     struct _Maybe_wrap_member_pointer
01224     {
01225       typedef _Tp type;
01226 
01227       static const _Tp&
01228       __do_wrap(const _Tp& __x)
01229       { return __x; }
01230 
01231       static _Tp&&
01232       __do_wrap(_Tp&& __x)
01233       { return static_cast<_Tp&&>(__x); }
01234     };
01235 
01236   /**
01237    *  Maps member pointers into instances of _Mem_fn but leaves all
01238    *  other function objects untouched. Used by tr1::bind(). This
01239    *  partial specialization handles the member pointer case.
01240    */
01241   template<typename _Tp, typename _Class>
01242     struct _Maybe_wrap_member_pointer<_Tp _Class::*>
01243     {
01244       typedef _Mem_fn<_Tp _Class::*> type;
01245 
01246       static type
01247       __do_wrap(_Tp _Class::* __pm)
01248       { return type(__pm); }
01249     };
01250 
01251   // Specialization needed to prevent "forming reference to void" errors when
01252   // bind<void>() is called, because argument deduction instantiates
01253   // _Maybe_wrap_member_pointer<void> outside the immediate context where
01254   // SFINAE applies.
01255   template<>
01256     struct _Maybe_wrap_member_pointer<void>
01257     {
01258       typedef void type;
01259     };
01260 
01261   // std::get<I> for volatile-qualified tuples
01262   template<std::size_t _Ind, typename... _Tp>
01263     inline auto
01264     __volget(volatile tuple<_Tp...>& __tuple)
01265     -> typename tuple_element<_Ind, tuple<_Tp...>>::type volatile&
01266     { return std::get<_Ind>(const_cast<tuple<_Tp...>&>(__tuple)); }
01267 
01268   // std::get<I> for const-volatile-qualified tuples
01269   template<std::size_t _Ind, typename... _Tp>
01270     inline auto
01271     __volget(const volatile tuple<_Tp...>& __tuple)
01272     -> typename tuple_element<_Ind, tuple<_Tp...>>::type const volatile&
01273     { return std::get<_Ind>(const_cast<const tuple<_Tp...>&>(__tuple)); }
01274 
01275   /// Type of the function object returned from bind().
01276   template<typename _Signature>
01277     struct _Bind;
01278 
01279    template<typename _Functor, typename... _Bound_args>
01280     class _Bind<_Functor(_Bound_args...)>
01281     : public _Weak_result_type<_Functor>
01282     {
01283       typedef _Bind __self_type;
01284       typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
01285     _Bound_indexes;
01286 
01287       _Functor _M_f;
01288       tuple<_Bound_args...> _M_bound_args;
01289 
01290       // Call unqualified
01291       template<typename _Result, typename... _Args, std::size_t... _Indexes>
01292     _Result
01293     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
01294     {
01295       return _M_f(_Mu<_Bound_args>()
01296               (get<_Indexes>(_M_bound_args), __args)...);
01297     }
01298 
01299       // Call as const
01300       template<typename _Result, typename... _Args, std::size_t... _Indexes>
01301     _Result
01302     __call_c(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
01303     {
01304       return _M_f(_Mu<_Bound_args>()
01305               (get<_Indexes>(_M_bound_args), __args)...);
01306     }
01307 
01308       // Call as volatile
01309       template<typename _Result, typename... _Args, std::size_t... _Indexes>
01310     _Result
01311     __call_v(tuple<_Args...>&& __args,
01312          _Index_tuple<_Indexes...>) volatile
01313     {
01314       return _M_f(_Mu<_Bound_args>()
01315               (__volget<_Indexes>(_M_bound_args), __args)...);
01316     }
01317 
01318       // Call as const volatile
01319       template<typename _Result, typename... _Args, std::size_t... _Indexes>
01320     _Result
01321     __call_c_v(tuple<_Args...>&& __args,
01322            _Index_tuple<_Indexes...>) const volatile
01323     {
01324       return _M_f(_Mu<_Bound_args>()
01325               (__volget<_Indexes>(_M_bound_args), __args)...);
01326     }
01327 
01328      public:
01329       template<typename... _Args>
01330     explicit _Bind(const _Functor& __f, _Args&&... __args)
01331     : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
01332     { }
01333 
01334       template<typename... _Args>
01335     explicit _Bind(_Functor&& __f, _Args&&... __args)
01336     : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
01337     { }
01338 
01339       _Bind(const _Bind&) = default;
01340 
01341       _Bind(_Bind&& __b)
01342       : _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
01343       { }
01344 
01345       // Call unqualified
01346       template<typename... _Args, typename _Result
01347     = decltype( std::declval<_Functor>()(
01348           _Mu<_Bound_args>()( std::declval<_Bound_args&>(),
01349                   std::declval<tuple<_Args...>&>() )... ) )>
01350     _Result
01351     operator()(_Args&&... __args)
01352     {
01353       return this->__call<_Result>(
01354           std::forward_as_tuple(std::forward<_Args>(__args)...),
01355           _Bound_indexes());
01356     }
01357 
01358       // Call as const
01359       template<typename... _Args, typename _Result
01360     = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
01361                typename add_const<_Functor>::type>::type>()(
01362           _Mu<_Bound_args>()( std::declval<const _Bound_args&>(),
01363                   std::declval<tuple<_Args...>&>() )... ) )>
01364     _Result
01365     operator()(_Args&&... __args) const
01366     {
01367       return this->__call_c<_Result>(
01368           std::forward_as_tuple(std::forward<_Args>(__args)...),
01369           _Bound_indexes());
01370     }
01371 
01372       // Call as volatile
01373       template<typename... _Args, typename _Result
01374     = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
01375                        typename add_volatile<_Functor>::type>::type>()(
01376           _Mu<_Bound_args>()( std::declval<volatile _Bound_args&>(),
01377                   std::declval<tuple<_Args...>&>() )... ) )>
01378     _Result
01379     operator()(_Args&&... __args) volatile
01380     {
01381       return this->__call_v<_Result>(
01382           std::forward_as_tuple(std::forward<_Args>(__args)...),
01383           _Bound_indexes());
01384     }
01385 
01386       // Call as const volatile
01387       template<typename... _Args, typename _Result
01388     = decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
01389                        typename add_cv<_Functor>::type>::type>()(
01390           _Mu<_Bound_args>()( std::declval<const volatile _Bound_args&>(),
01391                   std::declval<tuple<_Args...>&>() )... ) )>
01392     _Result
01393     operator()(_Args&&... __args) const volatile
01394     {
01395       return this->__call_c_v<_Result>(
01396           std::forward_as_tuple(std::forward<_Args>(__args)...),
01397           _Bound_indexes());
01398     }
01399     };
01400 
01401   /// Type of the function object returned from bind<R>().
01402   template<typename _Result, typename _Signature>
01403     struct _Bind_result;
01404 
01405   template<typename _Result, typename _Functor, typename... _Bound_args>
01406     class _Bind_result<_Result, _Functor(_Bound_args...)>
01407     {
01408       typedef _Bind_result __self_type;
01409       typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
01410     _Bound_indexes;
01411 
01412       _Functor _M_f;
01413       tuple<_Bound_args...> _M_bound_args;
01414 
01415       // sfinae types
01416       template<typename _Res>
01417     struct __enable_if_void : enable_if<is_void<_Res>::value, int> { };
01418       template<typename _Res>
01419     struct __disable_if_void : enable_if<!is_void<_Res>::value, int> { };
01420 
01421       // Call unqualified
01422       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01423     _Result
01424     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01425         typename __disable_if_void<_Res>::type = 0)
01426     {
01427       return _M_f(_Mu<_Bound_args>()
01428               (get<_Indexes>(_M_bound_args), __args)...);
01429     }
01430 
01431       // Call unqualified, return void
01432       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01433     void
01434     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01435         typename __enable_if_void<_Res>::type = 0)
01436     {
01437       _M_f(_Mu<_Bound_args>()
01438            (get<_Indexes>(_M_bound_args), __args)...);
01439     }
01440 
01441       // Call as const
01442       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01443     _Result
01444     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01445         typename __disable_if_void<_Res>::type = 0) const
01446     {
01447       return _M_f(_Mu<_Bound_args>()
01448               (get<_Indexes>(_M_bound_args), __args)...);
01449     }
01450 
01451       // Call as const, return void
01452       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01453     void
01454     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01455         typename __enable_if_void<_Res>::type = 0) const
01456     {
01457       _M_f(_Mu<_Bound_args>()
01458            (get<_Indexes>(_M_bound_args),  __args)...);
01459     }
01460 
01461       // Call as volatile
01462       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01463     _Result
01464     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01465         typename __disable_if_void<_Res>::type = 0) volatile
01466     {
01467       return _M_f(_Mu<_Bound_args>()
01468               (__volget<_Indexes>(_M_bound_args), __args)...);
01469     }
01470 
01471       // Call as volatile, return void
01472       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01473     void
01474     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01475         typename __enable_if_void<_Res>::type = 0) volatile
01476     {
01477       _M_f(_Mu<_Bound_args>()
01478            (__volget<_Indexes>(_M_bound_args), __args)...);
01479     }
01480 
01481       // Call as const volatile
01482       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01483     _Result
01484     __call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
01485         typename __disable_if_void<_Res>::type = 0) const volatile
01486     {
01487       return _M_f(_Mu<_Bound_args>()
01488               (__volget<_Indexes>(_M_bound_args), __args)...);
01489     }
01490 
01491       // Call as const volatile, return void
01492       template<typename _Res, typename... _Args, std::size_t... _Indexes>
01493     void
01494     __call(tuple<_Args...>&& __args,
01495            _Index_tuple<_Indexes...>,
01496         typename __enable_if_void<_Res>::type = 0) const volatile
01497     {
01498       _M_f(_Mu<_Bound_args>()
01499            (__volget<_Indexes>(_M_bound_args), __args)...);
01500     }
01501 
01502     public:
01503       typedef _Result result_type;
01504 
01505       template<typename... _Args>
01506     explicit _Bind_result(const _Functor& __f, _Args&&... __args)
01507     : _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
01508     { }
01509 
01510       template<typename... _Args>
01511     explicit _Bind_result(_Functor&& __f, _Args&&... __args)
01512     : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
01513     { }
01514 
01515       _Bind_result(const _Bind_result&) = default;
01516 
01517       _Bind_result(_Bind_result&& __b)
01518       : _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
01519       { }
01520 
01521       // Call unqualified
01522       template<typename... _Args>
01523     result_type
01524     operator()(_Args&&... __args)
01525     {
01526       return this->__call<_Result>(
01527           std::forward_as_tuple(std::forward<_Args>(__args)...),
01528           _Bound_indexes());
01529     }
01530 
01531       // Call as const
01532       template<typename... _Args>
01533     result_type
01534     operator()(_Args&&... __args) const
01535     {
01536       return this->__call<_Result>(
01537           std::forward_as_tuple(std::forward<_Args>(__args)...),
01538           _Bound_indexes());
01539     }
01540 
01541       // Call as volatile
01542       template<typename... _Args>
01543     result_type
01544     operator()(_Args&&... __args) volatile
01545     {
01546       return this->__call<_Result>(
01547           std::forward_as_tuple(std::forward<_Args>(__args)...),
01548           _Bound_indexes());
01549     }
01550 
01551       // Call as const volatile
01552       template<typename... _Args>
01553     result_type
01554     operator()(_Args&&... __args) const volatile
01555     {
01556       return this->__call<_Result>(
01557           std::forward_as_tuple(std::forward<_Args>(__args)...),
01558           _Bound_indexes());
01559     }
01560     };
01561 
01562   /**
01563    *  @brief Class template _Bind is always a bind expression.
01564    *  @ingroup binders
01565    */
01566   template<typename _Signature>
01567     struct is_bind_expression<_Bind<_Signature> >
01568     : public true_type { };
01569 
01570   /**
01571    *  @brief Class template _Bind is always a bind expression.
01572    *  @ingroup binders
01573    */
01574   template<typename _Signature>
01575     struct is_bind_expression<const _Bind<_Signature> >
01576     : public true_type { };
01577 
01578   /**
01579    *  @brief Class template _Bind is always a bind expression.
01580    *  @ingroup binders
01581    */
01582   template<typename _Signature>
01583     struct is_bind_expression<volatile _Bind<_Signature> >
01584     : public true_type { };
01585 
01586   /**
01587    *  @brief Class template _Bind is always a bind expression.
01588    *  @ingroup binders
01589    */
01590   template<typename _Signature>
01591     struct is_bind_expression<const volatile _Bind<_Signature>>
01592     : public true_type { };
01593 
01594   /**
01595    *  @brief Class template _Bind_result is always a bind expression.
01596    *  @ingroup binders
01597    */
01598   template<typename _Result, typename _Signature>
01599     struct is_bind_expression<_Bind_result<_Result, _Signature>>
01600     : public true_type { };
01601 
01602   /**
01603    *  @brief Class template _Bind_result is always a bind expression.
01604    *  @ingroup binders
01605    */
01606   template<typename _Result, typename _Signature>
01607     struct is_bind_expression<const _Bind_result<_Result, _Signature>>
01608     : public true_type { };
01609 
01610   /**
01611    *  @brief Class template _Bind_result is always a bind expression.
01612    *  @ingroup binders
01613    */
01614   template<typename _Result, typename _Signature>
01615     struct is_bind_expression<volatile _Bind_result<_Result, _Signature>>
01616     : public true_type { };
01617 
01618   /**
01619    *  @brief Class template _Bind_result is always a bind expression.
01620    *  @ingroup binders
01621    */
01622   template<typename _Result, typename _Signature>
01623     struct is_bind_expression<const volatile _Bind_result<_Result, _Signature>>
01624     : public true_type { };
01625 
01626   // Trait type used to remove std::bind() from overload set via SFINAE
01627   // when first argument has integer type, so that std::bind() will
01628   // not be a better match than ::bind() from the BSD Sockets API.
01629   template<typename _Tp, typename _Tp2 = typename decay<_Tp>::type>
01630     using __is_socketlike = __or_<is_integral<_Tp2>, is_enum<_Tp2>>;
01631 
01632   template<bool _SocketLike, typename _Func, typename... _BoundArgs>
01633     struct _Bind_helper
01634     {
01635       typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
01636     __maybe_type;
01637       typedef typename __maybe_type::type __func_type;
01638       typedef _Bind<__func_type(typename decay<_BoundArgs>::type...)> type;
01639     };
01640 
01641   // Partial specialization for is_socketlike == true, does not define
01642   // nested type so std::bind() will not participate in overload resolution
01643   // when the first argument might be a socket file descriptor.
01644   template<typename _Func, typename... _BoundArgs>
01645     struct _Bind_helper<true, _Func, _BoundArgs...>
01646     { };
01647 
01648   /**
01649    *  @brief Function template for std::bind.
01650    *  @ingroup binders
01651    */
01652   template<typename _Func, typename... _BoundArgs>
01653     inline typename
01654     _Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type
01655     bind(_Func&& __f, _BoundArgs&&... __args)
01656     {
01657       typedef _Bind_helper<false, _Func, _BoundArgs...> __helper_type;
01658       typedef typename __helper_type::__maybe_type __maybe_type;
01659       typedef typename __helper_type::type __result_type;
01660       return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
01661                std::forward<_BoundArgs>(__args)...);
01662     }
01663 
01664   template<typename _Result, typename _Func, typename... _BoundArgs>
01665     struct _Bindres_helper
01666     {
01667       typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
01668     __maybe_type;
01669       typedef typename __maybe_type::type __functor_type;
01670       typedef _Bind_result<_Result,
01671                __functor_type(typename decay<_BoundArgs>::type...)>
01672     type;
01673     };
01674 
01675   /**
01676    *  @brief Function template for std::bind<R>.
01677    *  @ingroup binders
01678    */
01679   template<typename _Result, typename _Func, typename... _BoundArgs>
01680     inline
01681     typename _Bindres_helper<_Result, _Func, _BoundArgs...>::type
01682     bind(_Func&& __f, _BoundArgs&&... __args)
01683     {
01684       typedef _Bindres_helper<_Result, _Func, _BoundArgs...> __helper_type;
01685       typedef typename __helper_type::__maybe_type __maybe_type;
01686       typedef typename __helper_type::type __result_type;
01687       return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
01688                std::forward<_BoundArgs>(__args)...);
01689     }
01690 
01691   template<typename _Signature>
01692     struct _Bind_simple;
01693 
01694   template<typename _Callable, typename... _Args>
01695     struct _Bind_simple<_Callable(_Args...)>
01696     {
01697       typedef typename result_of<_Callable(_Args...)>::type result_type;
01698 
01699       template<typename... _Args2, typename = typename
01700                enable_if< sizeof...(_Args) == sizeof...(_Args2)>::type>
01701         explicit
01702         _Bind_simple(const _Callable& __callable, _Args2&&... __args)
01703         : _M_bound(__callable, std::forward<_Args2>(__args)...)
01704         { }
01705 
01706       template<typename... _Args2, typename = typename
01707                enable_if< sizeof...(_Args) == sizeof...(_Args2)>::type>
01708         explicit
01709         _Bind_simple(_Callable&& __callable, _Args2&&... __args)
01710         : _M_bound(std::move(__callable), std::forward<_Args2>(__args)...)
01711         { }
01712 
01713       _Bind_simple(const _Bind_simple&) = default;
01714       _Bind_simple(_Bind_simple&&) = default;
01715 
01716       result_type
01717       operator()()
01718       {
01719         typedef typename _Build_index_tuple<sizeof...(_Args)>::__type _Indices;
01720         return _M_invoke(_Indices());
01721       }
01722 
01723     private:
01724 
01725       template<std::size_t... _Indices>
01726         typename result_of<_Callable(_Args...)>::type
01727         _M_invoke(_Index_tuple<_Indices...>)
01728         {
01729       // std::bind always forwards bound arguments as lvalues,
01730       // but this type can call functions which only accept rvalues.
01731           return std::forward<_Callable>(std::get<0>(_M_bound))(
01732               std::forward<_Args>(std::get<_Indices+1>(_M_bound))...);
01733         }
01734 
01735       std::tuple<_Callable, _Args...> _M_bound;
01736     };
01737 
01738   template<typename _Func, typename... _BoundArgs>
01739     struct _Bind_simple_helper
01740     {
01741       typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
01742         __maybe_type;
01743       typedef typename __maybe_type::type __func_type;
01744       typedef _Bind_simple<__func_type(typename decay<_BoundArgs>::type...)>
01745         __type;
01746     };
01747 
01748   // Simplified version of std::bind for internal use, without support for
01749   // unbound arguments, placeholders or nested bind expressions.
01750   template<typename _Callable, typename... _Args>
01751     typename _Bind_simple_helper<_Callable, _Args...>::__type
01752     __bind_simple(_Callable&& __callable, _Args&&... __args)
01753     {
01754       typedef _Bind_simple_helper<_Callable, _Args...> __helper_type;
01755       typedef typename __helper_type::__maybe_type __maybe_type;
01756       typedef typename __helper_type::__type __result_type;
01757       return __result_type(
01758           __maybe_type::__do_wrap( std::forward<_Callable>(__callable)),
01759           std::forward<_Args>(__args)...);
01760     }
01761 
01762   /**
01763    *  @brief Exception class thrown when class template function's
01764    *  operator() is called with an empty target.
01765    *  @ingroup exceptions
01766    */
01767   class bad_function_call : public std::exception
01768   {
01769   public:
01770     virtual ~bad_function_call() noexcept;
01771 
01772     const char* what() const noexcept;
01773   };
01774 
01775   /**
01776    *  Trait identifying "location-invariant" types, meaning that the
01777    *  address of the object (or any of its members) will not escape.
01778    *  Also implies a trivial copy constructor and assignment operator.
01779    */
01780   template<typename _Tp>
01781     struct __is_location_invariant
01782     : integral_constant<bool, (is_pointer<_Tp>::value
01783                    || is_member_pointer<_Tp>::value)>
01784     { };
01785 
01786   class _Undefined_class;
01787 
01788   union _Nocopy_types
01789   {
01790     void*       _M_object;
01791     const void* _M_const_object;
01792     void (*_M_function_pointer)();
01793     void (_Undefined_class::*_M_member_pointer)();
01794   };
01795 
01796   union _Any_data
01797   {
01798     void*       _M_access()       { return &_M_pod_data[0]; }
01799     const void* _M_access() const { return &_M_pod_data[0]; }
01800 
01801     template<typename _Tp>
01802       _Tp&
01803       _M_access()
01804       { return *static_cast<_Tp*>(_M_access()); }
01805 
01806     template<typename _Tp>
01807       const _Tp&
01808       _M_access() const
01809       { return *static_cast<const _Tp*>(_M_access()); }
01810 
01811     _Nocopy_types _M_unused;
01812     char _M_pod_data[sizeof(_Nocopy_types)];
01813   };
01814 
01815   enum _Manager_operation
01816   {
01817     __get_type_info,
01818     __get_functor_ptr,
01819     __clone_functor,
01820     __destroy_functor
01821   };
01822 
01823   // Simple type wrapper that helps avoid annoying const problems
01824   // when casting between void pointers and pointers-to-pointers.
01825   template<typename _Tp>
01826     struct _Simple_type_wrapper
01827     {
01828       _Simple_type_wrapper(_Tp __value) : __value(__value) { }
01829 
01830       _Tp __value;
01831     };
01832 
01833   template<typename _Tp>
01834     struct __is_location_invariant<_Simple_type_wrapper<_Tp> >
01835     : __is_location_invariant<_Tp>
01836     { };
01837 
01838   // Converts a reference to a function object into a callable
01839   // function object.
01840   template<typename _Functor>
01841     inline _Functor&
01842     __callable_functor(_Functor& __f)
01843     { return __f; }
01844 
01845   template<typename _Member, typename _Class>
01846     inline _Mem_fn<_Member _Class::*>
01847     __callable_functor(_Member _Class::* &__p)
01848     { return std::mem_fn(__p); }
01849 
01850   template<typename _Member, typename _Class>
01851     inline _Mem_fn<_Member _Class::*>
01852     __callable_functor(_Member _Class::* const &__p)
01853     { return std::mem_fn(__p); }
01854 
01855   template<typename _Member, typename _Class>
01856     inline _Mem_fn<_Member _Class::*>
01857     __callable_functor(_Member _Class::* volatile &__p)
01858     { return std::mem_fn(__p); }
01859 
01860   template<typename _Member, typename _Class>
01861     inline _Mem_fn<_Member _Class::*>
01862     __callable_functor(_Member _Class::* const volatile &__p)
01863     { return std::mem_fn(__p); }
01864 
01865   template<typename _Signature>
01866     class function;
01867 
01868   /// Base class of all polymorphic function object wrappers.
01869   class _Function_base
01870   {
01871   public:
01872     static const std::size_t _M_max_size = sizeof(_Nocopy_types);
01873     static const std::size_t _M_max_align = __alignof__(_Nocopy_types);
01874 
01875     template<typename _Functor>
01876       class _Base_manager
01877       {
01878       protected:
01879     static const bool __stored_locally =
01880     (__is_location_invariant<_Functor>::value
01881      && sizeof(_Functor) <= _M_max_size
01882      && __alignof__(_Functor) <= _M_max_align
01883      && (_M_max_align % __alignof__(_Functor) == 0));
01884 
01885     typedef integral_constant<bool, __stored_locally> _Local_storage;
01886 
01887     // Retrieve a pointer to the function object
01888     static _Functor*
01889     _M_get_pointer(const _Any_data& __source)
01890     {
01891       const _Functor* __ptr =
01892         __stored_locally? std::__addressof(__source._M_access<_Functor>())
01893         /* have stored a pointer */ : __source._M_access<_Functor*>();
01894       return const_cast<_Functor*>(__ptr);
01895     }
01896 
01897     // Clone a location-invariant function object that fits within
01898     // an _Any_data structure.
01899     static void
01900     _M_clone(_Any_data& __dest, const _Any_data& __source, true_type)
01901     {
01902       new (__dest._M_access()) _Functor(__source._M_access<_Functor>());
01903     }
01904 
01905     // Clone a function object that is not location-invariant or
01906     // that cannot fit into an _Any_data structure.
01907     static void
01908     _M_clone(_Any_data& __dest, const _Any_data& __source, false_type)
01909     {
01910       __dest._M_access<_Functor*>() =
01911         new _Functor(*__source._M_access<_Functor*>());
01912     }
01913 
01914     // Destroying a location-invariant object may still require
01915     // destruction.
01916     static void
01917     _M_destroy(_Any_data& __victim, true_type)
01918     {
01919       __victim._M_access<_Functor>().~_Functor();
01920     }
01921 
01922     // Destroying an object located on the heap.
01923     static void
01924     _M_destroy(_Any_data& __victim, false_type)
01925     {
01926       delete __victim._M_access<_Functor*>();
01927     }
01928 
01929       public:
01930     static bool
01931     _M_manager(_Any_data& __dest, const _Any_data& __source,
01932            _Manager_operation __op)
01933     {
01934       switch (__op)
01935         {
01936 #ifdef __GXX_RTTI
01937         case __get_type_info:
01938           __dest._M_access<const type_info*>() = &typeid(_Functor);
01939           break;
01940 #endif
01941         case __get_functor_ptr:
01942           __dest._M_access<_Functor*>() = _M_get_pointer(__source);
01943           break;
01944 
01945         case __clone_functor:
01946           _M_clone(__dest, __source, _Local_storage());
01947           break;
01948 
01949         case __destroy_functor:
01950           _M_destroy(__dest, _Local_storage());
01951           break;
01952         }
01953       return false;
01954     }
01955 
01956     static void
01957     _M_init_functor(_Any_data& __functor, _Functor&& __f)
01958     { _M_init_functor(__functor, std::move(__f), _Local_storage()); }
01959 
01960     template<typename _Signature>
01961       static bool
01962       _M_not_empty_function(const function<_Signature>& __f)
01963       { return static_cast<bool>(__f); }
01964 
01965     template<typename _Tp>
01966       static bool
01967       _M_not_empty_function(const _Tp*& __fp)
01968       { return __fp; }
01969 
01970     template<typename _Class, typename _Tp>
01971       static bool
01972       _M_not_empty_function(_Tp _Class::* const& __mp)
01973       { return __mp; }
01974 
01975     template<typename _Tp>
01976       static bool
01977       _M_not_empty_function(const _Tp&)
01978       { return true; }
01979 
01980       private:
01981     static void
01982     _M_init_functor(_Any_data& __functor, _Functor&& __f, true_type)
01983     { new (__functor._M_access()) _Functor(std::move(__f)); }
01984 
01985     static void
01986     _M_init_functor(_Any_data& __functor, _Functor&& __f, false_type)
01987     { __functor._M_access<_Functor*>() = new _Functor(std::move(__f)); }
01988       };
01989 
01990     template<typename _Functor>
01991       class _Ref_manager : public _Base_manager<_Functor*>
01992       {
01993     typedef _Function_base::_Base_manager<_Functor*> _Base;
01994 
01995       public:
01996     static bool
01997     _M_manager(_Any_data& __dest, const _Any_data& __source,
01998            _Manager_operation __op)
01999     {
02000       switch (__op)
02001         {
02002 #ifdef __GXX_RTTI
02003         case __get_type_info:
02004           __dest._M_access<const type_info*>() = &typeid(_Functor);
02005           break;
02006 #endif
02007         case __get_functor_ptr:
02008           __dest._M_access<_Functor*>() = *_Base::_M_get_pointer(__source);
02009           return is_const<_Functor>::value;
02010           break;
02011 
02012         default:
02013           _Base::_M_manager(__dest, __source, __op);
02014         }
02015       return false;
02016     }
02017 
02018     static void
02019     _M_init_functor(_Any_data& __functor, reference_wrapper<_Functor> __f)
02020     {
02021       _Base::_M_init_functor(__functor, std::__addressof(__f.get()));
02022     }
02023       };
02024 
02025     _Function_base() : _M_manager(0) { }
02026 
02027     ~_Function_base()
02028     {
02029       if (_M_manager)
02030     _M_manager(_M_functor, _M_functor, __destroy_functor);
02031     }
02032 
02033 
02034     bool _M_empty() const { return !_M_manager; }
02035 
02036     typedef bool (*_Manager_type)(_Any_data&, const _Any_data&,
02037                   _Manager_operation);
02038 
02039     _Any_data     _M_functor;
02040     _Manager_type _M_manager;
02041   };
02042 
02043   template<typename _Signature, typename _Functor>
02044     class _Function_handler;
02045 
02046   template<typename _Res, typename _Functor, typename... _ArgTypes>
02047     class _Function_handler<_Res(_ArgTypes...), _Functor>
02048     : public _Function_base::_Base_manager<_Functor>
02049     {
02050       typedef _Function_base::_Base_manager<_Functor> _Base;
02051 
02052     public:
02053       static _Res
02054       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02055       {
02056     return (*_Base::_M_get_pointer(__functor))(
02057         std::forward<_ArgTypes>(__args)...);
02058       }
02059     };
02060 
02061   template<typename _Functor, typename... _ArgTypes>
02062     class _Function_handler<void(_ArgTypes...), _Functor>
02063     : public _Function_base::_Base_manager<_Functor>
02064     {
02065       typedef _Function_base::_Base_manager<_Functor> _Base;
02066 
02067      public:
02068       static void
02069       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02070       {
02071     (*_Base::_M_get_pointer(__functor))(
02072         std::forward<_ArgTypes>(__args)...);
02073       }
02074     };
02075 
02076   template<typename _Res, typename _Functor, typename... _ArgTypes>
02077     class _Function_handler<_Res(_ArgTypes...), reference_wrapper<_Functor> >
02078     : public _Function_base::_Ref_manager<_Functor>
02079     {
02080       typedef _Function_base::_Ref_manager<_Functor> _Base;
02081 
02082      public:
02083       static _Res
02084       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02085       {
02086     return __callable_functor(**_Base::_M_get_pointer(__functor))(
02087           std::forward<_ArgTypes>(__args)...);
02088       }
02089     };
02090 
02091   template<typename _Functor, typename... _ArgTypes>
02092     class _Function_handler<void(_ArgTypes...), reference_wrapper<_Functor> >
02093     : public _Function_base::_Ref_manager<_Functor>
02094     {
02095       typedef _Function_base::_Ref_manager<_Functor> _Base;
02096 
02097      public:
02098       static void
02099       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02100       {
02101     __callable_functor(**_Base::_M_get_pointer(__functor))(
02102         std::forward<_ArgTypes>(__args)...);
02103       }
02104     };
02105 
02106   template<typename _Class, typename _Member, typename _Res,
02107        typename... _ArgTypes>
02108     class _Function_handler<_Res(_ArgTypes...), _Member _Class::*>
02109     : public _Function_handler<void(_ArgTypes...), _Member _Class::*>
02110     {
02111       typedef _Function_handler<void(_ArgTypes...), _Member _Class::*>
02112     _Base;
02113 
02114      public:
02115       static _Res
02116       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02117       {
02118     return std::mem_fn(_Base::_M_get_pointer(__functor)->__value)(
02119         std::forward<_ArgTypes>(__args)...);
02120       }
02121     };
02122 
02123   template<typename _Class, typename _Member, typename... _ArgTypes>
02124     class _Function_handler<void(_ArgTypes...), _Member _Class::*>
02125     : public _Function_base::_Base_manager<
02126          _Simple_type_wrapper< _Member _Class::* > >
02127     {
02128       typedef _Member _Class::* _Functor;
02129       typedef _Simple_type_wrapper<_Functor> _Wrapper;
02130       typedef _Function_base::_Base_manager<_Wrapper> _Base;
02131 
02132     public:
02133       static bool
02134       _M_manager(_Any_data& __dest, const _Any_data& __source,
02135          _Manager_operation __op)
02136       {
02137     switch (__op)
02138       {
02139 #ifdef __GXX_RTTI
02140       case __get_type_info:
02141         __dest._M_access<const type_info*>() = &typeid(_Functor);
02142         break;
02143 #endif
02144       case __get_functor_ptr:
02145         __dest._M_access<_Functor*>() =
02146           &_Base::_M_get_pointer(__source)->__value;
02147         break;
02148 
02149       default:
02150         _Base::_M_manager(__dest, __source, __op);
02151       }
02152     return false;
02153       }
02154 
02155       static void
02156       _M_invoke(const _Any_data& __functor, _ArgTypes... __args)
02157       {
02158     std::mem_fn(_Base::_M_get_pointer(__functor)->__value)(
02159         std::forward<_ArgTypes>(__args)...);
02160       }
02161     };
02162 
02163   /**
02164    *  @brief Primary class template for std::function.
02165    *  @ingroup functors
02166    *
02167    *  Polymorphic function wrapper.
02168    */
02169   template<typename _Res, typename... _ArgTypes>
02170     class function<_Res(_ArgTypes...)>
02171     : public _Maybe_unary_or_binary_function<_Res, _ArgTypes...>,
02172       private _Function_base
02173     {
02174       typedef _Res _Signature_type(_ArgTypes...);
02175 
02176       template<typename _Functor>
02177     using _Invoke = decltype(__callable_functor(std::declval<_Functor&>())
02178                  (std::declval<_ArgTypes>()...) );
02179 
02180       template<typename _CallRes, typename _Res1>
02181     struct _CheckResult
02182     : is_convertible<_CallRes, _Res1> { };
02183 
02184       template<typename _CallRes>
02185     struct _CheckResult<_CallRes, void>
02186     : true_type { };
02187 
02188       template<typename _Functor>
02189     using _Callable = _CheckResult<_Invoke<_Functor>, _Res>;
02190 
02191       template<typename _Cond, typename _Tp>
02192     using _Requires = typename enable_if<_Cond::value, _Tp>::type;
02193 
02194     public:
02195       typedef _Res result_type;
02196 
02197       // [3.7.2.1] construct/copy/destroy
02198 
02199       /**
02200        *  @brief Default construct creates an empty function call wrapper.
02201        *  @post @c !(bool)*this
02202        */
02203       function() noexcept
02204       : _Function_base() { }
02205 
02206       /**
02207        *  @brief Creates an empty function call wrapper.
02208        *  @post @c !(bool)*this
02209        */
02210       function(nullptr_t) noexcept
02211       : _Function_base() { }
02212 
02213       /**
02214        *  @brief %Function copy constructor.
02215        *  @param __x A %function object with identical call signature.
02216        *  @post @c bool(*this) == bool(__x)
02217        *
02218        *  The newly-created %function contains a copy of the target of @a
02219        *  __x (if it has one).
02220        */
02221       function(const function& __x);
02222 
02223       /**
02224        *  @brief %Function move constructor.
02225        *  @param __x A %function object rvalue with identical call signature.
02226        *
02227        *  The newly-created %function contains the target of @a __x
02228        *  (if it has one).
02229        */
02230       function(function&& __x) : _Function_base()
02231       {
02232     __x.swap(*this);
02233       }
02234 
02235       // TODO: needs allocator_arg_t
02236 
02237       /**
02238        *  @brief Builds a %function that targets a copy of the incoming
02239        *  function object.
02240        *  @param __f A %function object that is callable with parameters of
02241        *  type @c T1, @c T2, ..., @c TN and returns a value convertible
02242        *  to @c Res.
02243        *
02244        *  The newly-created %function object will target a copy of 
02245        *  @a __f. If @a __f is @c reference_wrapper<F>, then this function
02246        *  object will contain a reference to the function object @c
02247        *  __f.get(). If @a __f is a NULL function pointer or NULL
02248        *  pointer-to-member, the newly-created object will be empty.
02249        *
02250        *  If @a __f is a non-NULL function pointer or an object of type @c
02251        *  reference_wrapper<F>, this function will not throw.
02252        */
02253       template<typename _Functor,
02254            typename = _Requires<_Callable<_Functor>, void>>
02255     function(_Functor);
02256 
02257       /**
02258        *  @brief %Function assignment operator.
02259        *  @param __x A %function with identical call signature.
02260        *  @post @c (bool)*this == (bool)x
02261        *  @returns @c *this
02262        *
02263        *  The target of @a __x is copied to @c *this. If @a __x has no
02264        *  target, then @c *this will be empty.
02265        *
02266        *  If @a __x targets a function pointer or a reference to a function
02267        *  object, then this operation will not throw an %exception.
02268        */
02269       function&
02270       operator=(const function& __x)
02271       {
02272     function(__x).swap(*this);
02273     return *this;
02274       }
02275 
02276       /**
02277        *  @brief %Function move-assignment operator.
02278        *  @param __x A %function rvalue with identical call signature.
02279        *  @returns @c *this
02280        *
02281        *  The target of @a __x is moved to @c *this. If @a __x has no
02282        *  target, then @c *this will be empty.
02283        *
02284        *  If @a __x targets a function pointer or a reference to a function
02285        *  object, then this operation will not throw an %exception.
02286        */
02287       function&
02288       operator=(function&& __x)
02289       {
02290     function(std::move(__x)).swap(*this);
02291     return *this;
02292       }
02293 
02294       /**
02295        *  @brief %Function assignment to zero.
02296        *  @post @c !(bool)*this
02297        *  @returns @c *this
02298        *
02299        *  The target of @c *this is deallocated, leaving it empty.
02300        */
02301       function&
02302       operator=(nullptr_t)
02303       {
02304     if (_M_manager)
02305       {
02306         _M_manager(_M_functor, _M_functor, __destroy_functor);
02307         _M_manager = 0;
02308         _M_invoker = 0;
02309       }
02310     return *this;
02311       }
02312 
02313       /**
02314        *  @brief %Function assignment to a new target.
02315        *  @param __f A %function object that is callable with parameters of
02316        *  type @c T1, @c T2, ..., @c TN and returns a value convertible
02317        *  to @c Res.
02318        *  @return @c *this
02319        *
02320        *  This  %function object wrapper will target a copy of @a
02321        *  __f. If @a __f is @c reference_wrapper<F>, then this function
02322        *  object will contain a reference to the function object @c
02323        *  __f.get(). If @a __f is a NULL function pointer or NULL
02324        *  pointer-to-member, @c this object will be empty.
02325        *
02326        *  If @a __f is a non-NULL function pointer or an object of type @c
02327        *  reference_wrapper<F>, this function will not throw.
02328        */
02329       template<typename _Functor>
02330     _Requires<_Callable<_Functor>, function&>
02331     operator=(_Functor&& __f)
02332     {
02333       function(std::forward<_Functor>(__f)).swap(*this);
02334       return *this;
02335     }
02336 
02337       /// @overload
02338       template<typename _Functor>
02339     function&
02340     operator=(reference_wrapper<_Functor> __f) noexcept
02341     {
02342       function(__f).swap(*this);
02343       return *this;
02344     }
02345 
02346       // [3.7.2.2] function modifiers
02347 
02348       /**
02349        *  @brief Swap the targets of two %function objects.
02350        *  @param __x A %function with identical call signature.
02351        *
02352        *  Swap the targets of @c this function object and @a __f. This
02353        *  function will not throw an %exception.
02354        */
02355       void swap(function& __x)
02356       {
02357     std::swap(_M_functor, __x._M_functor);
02358     std::swap(_M_manager, __x._M_manager);
02359     std::swap(_M_invoker, __x._M_invoker);
02360       }
02361 
02362       // TODO: needs allocator_arg_t
02363       /*
02364       template<typename _Functor, typename _Alloc>
02365     void
02366     assign(_Functor&& __f, const _Alloc& __a)
02367     {
02368       function(allocator_arg, __a,
02369            std::forward<_Functor>(__f)).swap(*this);
02370     }
02371       */
02372 
02373       // [3.7.2.3] function capacity
02374 
02375       /**
02376        *  @brief Determine if the %function wrapper has a target.
02377        *
02378        *  @return @c true when this %function object contains a target,
02379        *  or @c false when it is empty.
02380        *
02381        *  This function will not throw an %exception.
02382        */
02383       explicit operator bool() const noexcept
02384       { return !_M_empty(); }
02385 
02386       // [3.7.2.4] function invocation
02387 
02388       /**
02389        *  @brief Invokes the function targeted by @c *this.
02390        *  @returns the result of the target.
02391        *  @throws bad_function_call when @c !(bool)*this
02392        *
02393        *  The function call operator invokes the target function object
02394        *  stored by @c this.
02395        */
02396       _Res operator()(_ArgTypes... __args) const;
02397 
02398 #ifdef __GXX_RTTI
02399       // [3.7.2.5] function target access
02400       /**
02401        *  @brief Determine the type of the target of this function object
02402        *  wrapper.
02403        *
02404        *  @returns the type identifier of the target function object, or
02405        *  @c typeid(void) if @c !(bool)*this.
02406        *
02407        *  This function will not throw an %exception.
02408        */
02409       const type_info& target_type() const noexcept;
02410 
02411       /**
02412        *  @brief Access the stored target function object.
02413        *
02414        *  @return Returns a pointer to the stored target function object,
02415        *  if @c typeid(Functor).equals(target_type()); otherwise, a NULL
02416        *  pointer.
02417        *
02418        * This function will not throw an %exception.
02419        */
02420       template<typename _Functor>       _Functor* target() noexcept;
02421 
02422       /// @overload
02423       template<typename _Functor> const _Functor* target() const noexcept;
02424 #endif
02425 
02426     private:
02427       typedef _Res (*_Invoker_type)(const _Any_data&, _ArgTypes...);
02428       _Invoker_type _M_invoker;
02429   };
02430 
02431   // Out-of-line member definitions.
02432   template<typename _Res, typename... _ArgTypes>
02433     function<_Res(_ArgTypes...)>::
02434     function(const function& __x)
02435     : _Function_base()
02436     {
02437       if (static_cast<bool>(__x))
02438     {
02439       _M_invoker = __x._M_invoker;
02440       _M_manager = __x._M_manager;
02441       __x._M_manager(_M_functor, __x._M_functor, __clone_functor);
02442     }
02443     }
02444 
02445   template<typename _Res, typename... _ArgTypes>
02446     template<typename _Functor, typename>
02447       function<_Res(_ArgTypes...)>::
02448       function(_Functor __f)
02449       : _Function_base()
02450       {
02451     typedef _Function_handler<_Signature_type, _Functor> _My_handler;
02452 
02453     if (_My_handler::_M_not_empty_function(__f))
02454       {
02455         _My_handler::_M_init_functor(_M_functor, std::move(__f));
02456         _M_invoker = &_My_handler::_M_invoke;
02457         _M_manager = &_My_handler::_M_manager;
02458       }
02459       }
02460 
02461   template<typename _Res, typename... _ArgTypes>
02462     _Res
02463     function<_Res(_ArgTypes...)>::
02464     operator()(_ArgTypes... __args) const
02465     {
02466       if (_M_empty())
02467     __throw_bad_function_call();
02468       return _M_invoker(_M_functor, std::forward<_ArgTypes>(__args)...);
02469     }
02470 
02471 #ifdef __GXX_RTTI
02472   template<typename _Res, typename... _ArgTypes>
02473     const type_info&
02474     function<_Res(_ArgTypes...)>::
02475     target_type() const noexcept
02476     {
02477       if (_M_manager)
02478     {
02479       _Any_data __typeinfo_result;
02480       _M_manager(__typeinfo_result, _M_functor, __get_type_info);
02481       return *__typeinfo_result._M_access<const type_info*>();
02482     }
02483       else
02484     return typeid(void);
02485     }
02486 
02487   template<typename _Res, typename... _ArgTypes>
02488     template<typename _Functor>
02489       _Functor*
02490       function<_Res(_ArgTypes...)>::
02491       target() noexcept
02492       {
02493     if (typeid(_Functor) == target_type() && _M_manager)
02494       {
02495         _Any_data __ptr;
02496         if (_M_manager(__ptr, _M_functor, __get_functor_ptr)
02497         && !is_const<_Functor>::value)
02498           return 0;
02499         else
02500           return __ptr._M_access<_Functor*>();
02501       }
02502     else
02503       return 0;
02504       }
02505 
02506   template<typename _Res, typename... _ArgTypes>
02507     template<typename _Functor>
02508       const _Functor*
02509       function<_Res(_ArgTypes...)>::
02510       target() const noexcept
02511       {
02512     if (typeid(_Functor) == target_type() && _M_manager)
02513       {
02514         _Any_data __ptr;
02515         _M_manager(__ptr, _M_functor, __get_functor_ptr);
02516         return __ptr._M_access<const _Functor*>();
02517       }
02518     else
02519       return 0;
02520       }
02521 #endif
02522 
02523   // [20.7.15.2.6] null pointer comparisons
02524 
02525   /**
02526    *  @brief Compares a polymorphic function object wrapper against 0
02527    *  (the NULL pointer).
02528    *  @returns @c true if the wrapper has no target, @c false otherwise
02529    *
02530    *  This function will not throw an %exception.
02531    */
02532   template<typename _Res, typename... _Args>
02533     inline bool
02534     operator==(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
02535     { return !static_cast<bool>(__f); }
02536 
02537   /// @overload
02538   template<typename _Res, typename... _Args>
02539     inline bool
02540     operator==(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
02541     { return !static_cast<bool>(__f); }
02542 
02543   /**
02544    *  @brief Compares a polymorphic function object wrapper against 0
02545    *  (the NULL pointer).
02546    *  @returns @c false if the wrapper has no target, @c true otherwise
02547    *
02548    *  This function will not throw an %exception.
02549    */
02550   template<typename _Res, typename... _Args>
02551     inline bool
02552     operator!=(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
02553     { return static_cast<bool>(__f); }
02554 
02555   /// @overload
02556   template<typename _Res, typename... _Args>
02557     inline bool
02558     operator!=(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
02559     { return static_cast<bool>(__f); }
02560 
02561   // [20.7.15.2.7] specialized algorithms
02562 
02563   /**
02564    *  @brief Swap the targets of two polymorphic function object wrappers.
02565    *
02566    *  This function will not throw an %exception.
02567    */
02568   template<typename _Res, typename... _Args>
02569     inline void
02570     swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y)
02571     { __x.swap(__y); }
02572 
02573 _GLIBCXX_END_NAMESPACE_VERSION
02574 } // namespace std
02575 
02576 #endif // C++11
02577 
02578 #endif // _GLIBCXX_FUNCTIONAL