libstdc++
tuple
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00001 // <tuple> -*- C++ -*-
00002 
00003 // Copyright (C) 2007-2014 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 /** @file include/tuple
00026  *  This is a Standard C++ Library header.
00027  */
00028 
00029 #ifndef _GLIBCXX_TUPLE
00030 #define _GLIBCXX_TUPLE 1
00031 
00032 #pragma GCC system_header
00033 
00034 #if __cplusplus < 201103L
00035 # include <bits/c++0x_warning.h>
00036 #else
00037 
00038 #include <utility>
00039 #include <array>
00040 #include <bits/uses_allocator.h>
00041 
00042 namespace std _GLIBCXX_VISIBILITY(default)
00043 {
00044 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00045 
00046   /**
00047    *  @addtogroup utilities
00048    *  @{
00049    */
00050 
00051   // Adds a const reference to a non-reference type.
00052   template<typename _Tp>
00053     struct __add_c_ref
00054     { typedef const _Tp& type; };
00055 
00056   template<typename _Tp>
00057     struct __add_c_ref<_Tp&>
00058     { typedef _Tp& type; };
00059 
00060   // Adds a reference to a non-reference type.
00061   template<typename _Tp>
00062     struct __add_ref
00063     { typedef _Tp& type; };
00064 
00065   template<typename _Tp>
00066     struct __add_ref<_Tp&>
00067     { typedef _Tp& type; };
00068 
00069   // Adds an rvalue reference to a non-reference type.
00070   template<typename _Tp>
00071     struct __add_r_ref
00072     { typedef _Tp&& type; };
00073 
00074   template<typename _Tp>
00075     struct __add_r_ref<_Tp&>
00076     { typedef _Tp& type; };
00077 
00078   template<std::size_t _Idx, typename _Head, bool _IsEmptyNotFinal>
00079     struct _Head_base;
00080 
00081   template<std::size_t _Idx, typename _Head>
00082     struct _Head_base<_Idx, _Head, true>
00083     : public _Head
00084     {
00085       constexpr _Head_base()
00086       : _Head() { }
00087 
00088       constexpr _Head_base(const _Head& __h)
00089       : _Head(__h) { }
00090 
00091       template<typename _UHead, typename = typename
00092            enable_if<!is_convertible<_UHead,
00093                                      __uses_alloc_base>::value>::type>
00094         constexpr _Head_base(_UHead&& __h)
00095     : _Head(std::forward<_UHead>(__h)) { }
00096 
00097       _Head_base(__uses_alloc0)
00098       : _Head() { }
00099 
00100       template<typename _Alloc>
00101     _Head_base(__uses_alloc1<_Alloc> __a)
00102     : _Head(allocator_arg, *__a._M_a) { }
00103 
00104       template<typename _Alloc>
00105     _Head_base(__uses_alloc2<_Alloc> __a)
00106     : _Head(*__a._M_a) { }
00107 
00108       template<typename _UHead>
00109     _Head_base(__uses_alloc0, _UHead&& __uhead)
00110     : _Head(std::forward<_UHead>(__uhead)) { }
00111 
00112       template<typename _Alloc, typename _UHead>
00113     _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
00114     : _Head(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead)) { }
00115 
00116       template<typename _Alloc, typename _UHead>
00117     _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
00118     : _Head(std::forward<_UHead>(__uhead), *__a._M_a) { }
00119 
00120       static constexpr _Head&
00121       _M_head(_Head_base& __b) noexcept { return __b; }
00122 
00123       static constexpr const _Head&
00124       _M_head(const _Head_base& __b) noexcept { return __b; }
00125     };
00126 
00127   template<std::size_t _Idx, typename _Head>
00128     struct _Head_base<_Idx, _Head, false>
00129     {
00130       constexpr _Head_base()
00131       : _M_head_impl() { }
00132 
00133       constexpr _Head_base(const _Head& __h)
00134       : _M_head_impl(__h) { }
00135 
00136       template<typename _UHead, typename = typename
00137            enable_if<!is_convertible<_UHead,
00138                                      __uses_alloc_base>::value>::type>
00139         constexpr _Head_base(_UHead&& __h)
00140     : _M_head_impl(std::forward<_UHead>(__h)) { }
00141 
00142       _Head_base(__uses_alloc0)
00143       : _M_head_impl() { }
00144 
00145       template<typename _Alloc>
00146     _Head_base(__uses_alloc1<_Alloc> __a)
00147     : _M_head_impl(allocator_arg, *__a._M_a) { }
00148 
00149       template<typename _Alloc>
00150     _Head_base(__uses_alloc2<_Alloc> __a)
00151     : _M_head_impl(*__a._M_a) { }
00152 
00153       template<typename _UHead>
00154     _Head_base(__uses_alloc0, _UHead&& __uhead)
00155     : _M_head_impl(std::forward<_UHead>(__uhead)) { }
00156 
00157       template<typename _Alloc, typename _UHead>
00158     _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
00159     : _M_head_impl(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead))
00160     { }
00161 
00162       template<typename _Alloc, typename _UHead>
00163     _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
00164     : _M_head_impl(std::forward<_UHead>(__uhead), *__a._M_a) { }
00165 
00166       static constexpr _Head&
00167       _M_head(_Head_base& __b) noexcept { return __b._M_head_impl; }
00168 
00169       static constexpr const _Head&
00170       _M_head(const _Head_base& __b) noexcept { return __b._M_head_impl; }
00171 
00172       _Head _M_head_impl;
00173     };
00174 
00175   /**
00176    * Contains the actual implementation of the @c tuple template, stored
00177    * as a recursive inheritance hierarchy from the first element (most
00178    * derived class) to the last (least derived class). The @c Idx
00179    * parameter gives the 0-based index of the element stored at this
00180    * point in the hierarchy; we use it to implement a constant-time
00181    * get() operation.
00182    */
00183   template<std::size_t _Idx, typename... _Elements>
00184     struct _Tuple_impl; 
00185 
00186   /**
00187    * Zero-element tuple implementation. This is the basis case for the 
00188    * inheritance recursion.
00189    */
00190   template<std::size_t _Idx>
00191     struct _Tuple_impl<_Idx>
00192     {
00193       template<std::size_t, typename...> friend class _Tuple_impl;
00194 
00195       _Tuple_impl() = default;
00196 
00197       template<typename _Alloc>
00198         _Tuple_impl(allocator_arg_t, const _Alloc&) { }
00199 
00200       template<typename _Alloc>
00201         _Tuple_impl(allocator_arg_t, const _Alloc&, const _Tuple_impl&) { }
00202 
00203       template<typename _Alloc>
00204         _Tuple_impl(allocator_arg_t, const _Alloc&, _Tuple_impl&&) { }
00205 
00206     protected:
00207       void _M_swap(_Tuple_impl&) noexcept { /* no-op */ }
00208     };
00209 
00210   template<typename _Tp>
00211     struct __is_empty_non_tuple : is_empty<_Tp> { };
00212 
00213   // Using EBO for elements that are tuples causes ambiguous base errors.
00214   template<typename _El0, typename... _El>
00215     struct __is_empty_non_tuple<tuple<_El0, _El...>> : false_type { };
00216 
00217   // Use the Empty Base-class Optimization for empty, non-final types.
00218   template<typename _Tp>
00219     using __empty_not_final
00220     = typename conditional<__is_final(_Tp), false_type,
00221                __is_empty_non_tuple<_Tp>>::type;
00222 
00223   /**
00224    * Recursive tuple implementation. Here we store the @c Head element
00225    * and derive from a @c Tuple_impl containing the remaining elements
00226    * (which contains the @c Tail).
00227    */
00228   template<std::size_t _Idx, typename _Head, typename... _Tail>
00229     struct _Tuple_impl<_Idx, _Head, _Tail...>
00230     : public _Tuple_impl<_Idx + 1, _Tail...>,
00231       private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
00232     {
00233       template<std::size_t, typename...> friend class _Tuple_impl;
00234 
00235       typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
00236       typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
00237 
00238       static constexpr _Head&  
00239       _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
00240 
00241       static constexpr const _Head&
00242       _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
00243 
00244       static constexpr _Inherited&
00245       _M_tail(_Tuple_impl& __t) noexcept { return __t; }
00246 
00247       static constexpr const _Inherited&
00248       _M_tail(const _Tuple_impl& __t) noexcept { return __t; }
00249 
00250       constexpr _Tuple_impl()
00251       : _Inherited(), _Base() { }
00252 
00253       explicit 
00254       constexpr _Tuple_impl(const _Head& __head, const _Tail&... __tail)
00255       : _Inherited(__tail...), _Base(__head) { }
00256 
00257       template<typename _UHead, typename... _UTail, typename = typename
00258                enable_if<sizeof...(_Tail) == sizeof...(_UTail)>::type> 
00259         explicit
00260         constexpr _Tuple_impl(_UHead&& __head, _UTail&&... __tail)
00261     : _Inherited(std::forward<_UTail>(__tail)...),
00262       _Base(std::forward<_UHead>(__head)) { }
00263 
00264       constexpr _Tuple_impl(const _Tuple_impl&) = default;
00265 
00266       constexpr
00267       _Tuple_impl(_Tuple_impl&& __in)
00268       noexcept(__and_<is_nothrow_move_constructible<_Head>,
00269                   is_nothrow_move_constructible<_Inherited>>::value)
00270       : _Inherited(std::move(_M_tail(__in))), 
00271     _Base(std::forward<_Head>(_M_head(__in))) { }
00272 
00273       template<typename... _UElements>
00274         constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UElements...>& __in)
00275     : _Inherited(_Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
00276       _Base(_Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
00277 
00278       template<typename _UHead, typename... _UTails>
00279         constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
00280     : _Inherited(std::move
00281              (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
00282       _Base(std::forward<_UHead>
00283         (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
00284 
00285       template<typename _Alloc>
00286     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
00287     : _Inherited(__tag, __a),
00288           _Base(__use_alloc<_Head>(__a)) { }
00289 
00290       template<typename _Alloc>
00291     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00292             const _Head& __head, const _Tail&... __tail)
00293     : _Inherited(__tag, __a, __tail...),
00294           _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
00295 
00296       template<typename _Alloc, typename _UHead, typename... _UTail,
00297                typename = typename enable_if<sizeof...(_Tail)
00298                          == sizeof...(_UTail)>::type>
00299     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00300                 _UHead&& __head, _UTail&&... __tail)
00301     : _Inherited(__tag, __a, std::forward<_UTail>(__tail)...),
00302           _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
00303             std::forward<_UHead>(__head)) { }
00304 
00305       template<typename _Alloc>
00306         _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00307                 const _Tuple_impl& __in)
00308     : _Inherited(__tag, __a, _M_tail(__in)), 
00309           _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
00310 
00311       template<typename _Alloc>
00312     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00313                 _Tuple_impl&& __in)
00314     : _Inherited(__tag, __a, std::move(_M_tail(__in))), 
00315       _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
00316             std::forward<_Head>(_M_head(__in))) { }
00317 
00318       template<typename _Alloc, typename... _UElements>
00319     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00320                 const _Tuple_impl<_Idx, _UElements...>& __in)
00321     : _Inherited(__tag, __a,
00322              _Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
00323       _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
00324         _Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
00325 
00326       template<typename _Alloc, typename _UHead, typename... _UTails>
00327     _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
00328                 _Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
00329     : _Inherited(__tag, __a, std::move
00330              (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
00331       _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
00332                 std::forward<_UHead>
00333         (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
00334 
00335       _Tuple_impl&
00336       operator=(const _Tuple_impl& __in)
00337       {
00338     _M_head(*this) = _M_head(__in);
00339     _M_tail(*this) = _M_tail(__in);
00340     return *this;
00341       }
00342 
00343       _Tuple_impl&
00344       operator=(_Tuple_impl&& __in)
00345       noexcept(__and_<is_nothrow_move_assignable<_Head>,
00346                   is_nothrow_move_assignable<_Inherited>>::value)
00347       {
00348     _M_head(*this) = std::forward<_Head>(_M_head(__in));
00349     _M_tail(*this) = std::move(_M_tail(__in));
00350     return *this;
00351       }
00352 
00353       template<typename... _UElements>
00354         _Tuple_impl&
00355         operator=(const _Tuple_impl<_Idx, _UElements...>& __in)
00356         {
00357       _M_head(*this) = _Tuple_impl<_Idx, _UElements...>::_M_head(__in);
00358       _M_tail(*this) = _Tuple_impl<_Idx, _UElements...>::_M_tail(__in);
00359       return *this;
00360     }
00361 
00362       template<typename _UHead, typename... _UTails>
00363         _Tuple_impl&
00364         operator=(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
00365         {
00366       _M_head(*this) = std::forward<_UHead>
00367         (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in));
00368       _M_tail(*this) = std::move
00369         (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in));
00370       return *this;
00371     }
00372 
00373     protected:
00374       void
00375       _M_swap(_Tuple_impl& __in)
00376       noexcept(noexcept(swap(std::declval<_Head&>(),
00377                  std::declval<_Head&>()))
00378            && noexcept(_M_tail(__in)._M_swap(_M_tail(__in))))
00379       {
00380     using std::swap;
00381     swap(_M_head(*this), _M_head(__in));
00382     _Inherited::_M_swap(_M_tail(__in));
00383       }
00384     };
00385 
00386   /// Primary class template, tuple
00387   template<typename... _Elements> 
00388     class tuple : public _Tuple_impl<0, _Elements...>
00389     {
00390       typedef _Tuple_impl<0, _Elements...> _Inherited;
00391 
00392     public:
00393       constexpr tuple()
00394       : _Inherited() { }
00395 
00396       explicit
00397       constexpr tuple(const _Elements&... __elements)
00398       : _Inherited(__elements...) { }
00399 
00400       template<typename... _UElements, typename = typename
00401         enable_if<__and_<is_convertible<_UElements,
00402                     _Elements>...>::value>::type>
00403     explicit
00404         constexpr tuple(_UElements&&... __elements)
00405     : _Inherited(std::forward<_UElements>(__elements)...) { }
00406 
00407       constexpr tuple(const tuple&) = default;
00408 
00409       constexpr tuple(tuple&&) = default; 
00410 
00411       template<typename... _UElements, typename = typename
00412         enable_if<__and_<is_convertible<const _UElements&,
00413                     _Elements>...>::value>::type>
00414         constexpr tuple(const tuple<_UElements...>& __in)
00415         : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
00416         { }
00417 
00418       template<typename... _UElements, typename = typename
00419         enable_if<__and_<is_convertible<_UElements,
00420                     _Elements>...>::value>::type>
00421         constexpr tuple(tuple<_UElements...>&& __in)
00422         : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
00423 
00424       // Allocator-extended constructors.
00425 
00426       template<typename _Alloc>
00427     tuple(allocator_arg_t __tag, const _Alloc& __a)
00428     : _Inherited(__tag, __a) { }
00429 
00430       template<typename _Alloc>
00431     tuple(allocator_arg_t __tag, const _Alloc& __a,
00432           const _Elements&... __elements)
00433     : _Inherited(__tag, __a, __elements...) { }
00434 
00435       template<typename _Alloc, typename... _UElements, typename = typename
00436            enable_if<sizeof...(_UElements)
00437              == sizeof...(_Elements)>::type>
00438     tuple(allocator_arg_t __tag, const _Alloc& __a,
00439           _UElements&&... __elements)
00440     : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
00441         { }
00442 
00443       template<typename _Alloc>
00444     tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
00445     : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
00446 
00447       template<typename _Alloc>
00448     tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
00449     : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
00450 
00451       template<typename _Alloc, typename... _UElements, typename = typename
00452            enable_if<sizeof...(_UElements)
00453              == sizeof...(_Elements)>::type>
00454     tuple(allocator_arg_t __tag, const _Alloc& __a,
00455           const tuple<_UElements...>& __in)
00456     : _Inherited(__tag, __a,
00457                  static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
00458     { }
00459 
00460       template<typename _Alloc, typename... _UElements, typename = typename
00461            enable_if<sizeof...(_UElements)
00462              == sizeof...(_Elements)>::type>
00463     tuple(allocator_arg_t __tag, const _Alloc& __a,
00464           tuple<_UElements...>&& __in)
00465     : _Inherited(__tag, __a,
00466                  static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
00467     { }
00468 
00469       tuple&
00470       operator=(const tuple& __in)
00471       {
00472     static_cast<_Inherited&>(*this) = __in;
00473     return *this;
00474       }
00475 
00476       tuple&
00477       operator=(tuple&& __in)
00478       noexcept(is_nothrow_move_assignable<_Inherited>::value)
00479       {
00480     static_cast<_Inherited&>(*this) = std::move(__in);
00481     return *this;
00482       }
00483 
00484       template<typename... _UElements, typename = typename
00485            enable_if<sizeof...(_UElements)
00486              == sizeof...(_Elements)>::type>
00487         tuple&
00488         operator=(const tuple<_UElements...>& __in)
00489         {
00490       static_cast<_Inherited&>(*this) = __in;
00491       return *this;
00492     }
00493 
00494       template<typename... _UElements, typename = typename
00495            enable_if<sizeof...(_UElements)
00496              == sizeof...(_Elements)>::type>
00497         tuple&
00498         operator=(tuple<_UElements...>&& __in)
00499         {
00500       static_cast<_Inherited&>(*this) = std::move(__in);
00501       return *this;
00502     }
00503 
00504       void
00505       swap(tuple& __in)
00506       noexcept(noexcept(__in._M_swap(__in)))
00507       { _Inherited::_M_swap(__in); }
00508     };
00509 
00510   // Explicit specialization, zero-element tuple.
00511   template<>  
00512     class tuple<>
00513     {
00514     public:
00515       void swap(tuple&) noexcept { /* no-op */ }
00516     };
00517 
00518   /// Partial specialization, 2-element tuple.
00519   /// Includes construction and assignment from a pair.
00520   template<typename _T1, typename _T2>
00521     class tuple<_T1, _T2> : public _Tuple_impl<0, _T1, _T2>
00522     {
00523       typedef _Tuple_impl<0, _T1, _T2> _Inherited;
00524 
00525     public:
00526       constexpr tuple()
00527       : _Inherited() { }
00528 
00529       explicit
00530       constexpr tuple(const _T1& __a1, const _T2& __a2)
00531       : _Inherited(__a1, __a2) { }
00532 
00533       template<typename _U1, typename _U2, typename = typename
00534            enable_if<__and_<is_convertible<_U1, _T1>,
00535                 is_convertible<_U2, _T2>>::value>::type>
00536         explicit
00537         constexpr tuple(_U1&& __a1, _U2&& __a2)
00538     : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
00539 
00540       constexpr tuple(const tuple&) = default;
00541 
00542       constexpr tuple(tuple&&) = default;
00543 
00544       template<typename _U1, typename _U2, typename = typename
00545     enable_if<__and_<is_convertible<const _U1&, _T1>,
00546              is_convertible<const _U2&, _T2>>::value>::type>
00547         constexpr tuple(const tuple<_U1, _U2>& __in)
00548     : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
00549 
00550       template<typename _U1, typename _U2, typename = typename
00551            enable_if<__and_<is_convertible<_U1, _T1>,
00552                 is_convertible<_U2, _T2>>::value>::type>
00553         constexpr tuple(tuple<_U1, _U2>&& __in)
00554     : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
00555 
00556       template<typename _U1, typename _U2, typename = typename
00557     enable_if<__and_<is_convertible<const _U1&, _T1>,
00558              is_convertible<const _U2&, _T2>>::value>::type>
00559         constexpr tuple(const pair<_U1, _U2>& __in)
00560     : _Inherited(__in.first, __in.second) { }
00561 
00562       template<typename _U1, typename _U2, typename = typename
00563            enable_if<__and_<is_convertible<_U1, _T1>,
00564                 is_convertible<_U2, _T2>>::value>::type>
00565         constexpr tuple(pair<_U1, _U2>&& __in)
00566     : _Inherited(std::forward<_U1>(__in.first),
00567              std::forward<_U2>(__in.second)) { }
00568 
00569       // Allocator-extended constructors.
00570 
00571       template<typename _Alloc>
00572     tuple(allocator_arg_t __tag, const _Alloc& __a)
00573     : _Inherited(__tag, __a) { }
00574 
00575       template<typename _Alloc>
00576     tuple(allocator_arg_t __tag, const _Alloc& __a,
00577           const _T1& __a1, const _T2& __a2)
00578     : _Inherited(__tag, __a, __a1, __a2) { }
00579 
00580       template<typename _Alloc, typename _U1, typename _U2>
00581     tuple(allocator_arg_t __tag, const _Alloc& __a, _U1&& __a1, _U2&& __a2)
00582     : _Inherited(__tag, __a, std::forward<_U1>(__a1),
00583                  std::forward<_U2>(__a2)) { }
00584 
00585       template<typename _Alloc>
00586     tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
00587     : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
00588 
00589       template<typename _Alloc>
00590     tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
00591     : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
00592 
00593       template<typename _Alloc, typename _U1, typename _U2>
00594     tuple(allocator_arg_t __tag, const _Alloc& __a,
00595           const tuple<_U1, _U2>& __in)
00596     : _Inherited(__tag, __a,
00597                  static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
00598     { }
00599 
00600       template<typename _Alloc, typename _U1, typename _U2>
00601     tuple(allocator_arg_t __tag, const _Alloc& __a, tuple<_U1, _U2>&& __in)
00602     : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
00603     { }
00604 
00605       template<typename _Alloc, typename _U1, typename _U2>
00606         tuple(allocator_arg_t __tag, const _Alloc& __a,
00607           const pair<_U1, _U2>& __in)
00608     : _Inherited(__tag, __a, __in.first, __in.second) { }
00609 
00610       template<typename _Alloc, typename _U1, typename _U2>
00611         tuple(allocator_arg_t __tag, const _Alloc& __a, pair<_U1, _U2>&& __in)
00612     : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
00613              std::forward<_U2>(__in.second)) { }
00614 
00615       tuple&
00616       operator=(const tuple& __in)
00617       {
00618     static_cast<_Inherited&>(*this) = __in;
00619     return *this;
00620       }
00621 
00622       tuple&
00623       operator=(tuple&& __in)
00624       noexcept(is_nothrow_move_assignable<_Inherited>::value)
00625       {
00626     static_cast<_Inherited&>(*this) = std::move(__in);
00627     return *this;
00628       }
00629 
00630       template<typename _U1, typename _U2>
00631         tuple&
00632         operator=(const tuple<_U1, _U2>& __in)
00633         {
00634       static_cast<_Inherited&>(*this) = __in;
00635       return *this;
00636     }
00637 
00638       template<typename _U1, typename _U2>
00639         tuple&
00640         operator=(tuple<_U1, _U2>&& __in)
00641         {
00642       static_cast<_Inherited&>(*this) = std::move(__in);
00643       return *this;
00644     }
00645 
00646       template<typename _U1, typename _U2>
00647         tuple&
00648         operator=(const pair<_U1, _U2>& __in)
00649         {
00650       this->_M_head(*this) = __in.first;
00651       this->_M_tail(*this)._M_head(*this) = __in.second;
00652       return *this;
00653     }
00654 
00655       template<typename _U1, typename _U2>
00656         tuple&
00657         operator=(pair<_U1, _U2>&& __in)
00658         {
00659       this->_M_head(*this) = std::forward<_U1>(__in.first);
00660       this->_M_tail(*this)._M_head(*this) = std::forward<_U2>(__in.second);
00661       return *this;
00662     }
00663 
00664       void
00665       swap(tuple& __in)
00666       noexcept(noexcept(__in._M_swap(__in)))
00667       { _Inherited::_M_swap(__in); }
00668     };
00669 
00670 
00671   /// Gives the type of the ith element of a given tuple type.
00672   template<std::size_t __i, typename _Tp>
00673     struct tuple_element;
00674 
00675   /**
00676    * Recursive case for tuple_element: strip off the first element in
00677    * the tuple and retrieve the (i-1)th element of the remaining tuple.
00678    */
00679   template<std::size_t __i, typename _Head, typename... _Tail>
00680     struct tuple_element<__i, tuple<_Head, _Tail...> >
00681     : tuple_element<__i - 1, tuple<_Tail...> > { };
00682 
00683   /**
00684    * Basis case for tuple_element: The first element is the one we're seeking.
00685    */
00686   template<typename _Head, typename... _Tail>
00687     struct tuple_element<0, tuple<_Head, _Tail...> >
00688     {
00689       typedef _Head type;
00690     };
00691 
00692   template<std::size_t __i, typename _Tp>
00693     struct tuple_element<__i, const _Tp>
00694     {
00695       typedef typename
00696       add_const<typename tuple_element<__i, _Tp>::type>::type type;
00697     };
00698 
00699   template<std::size_t __i, typename _Tp>
00700     struct tuple_element<__i, volatile _Tp>
00701     {
00702       typedef typename
00703       add_volatile<typename tuple_element<__i, _Tp>::type>::type type;
00704     };
00705 
00706   template<std::size_t __i, typename _Tp>
00707     struct tuple_element<__i, const volatile _Tp>
00708     {
00709       typedef typename
00710       add_cv<typename tuple_element<__i, _Tp>::type>::type type;
00711     };
00712 
00713 #if __cplusplus > 201103L
00714   template<std::size_t __i, typename _Tp>
00715     using tuple_element_t = typename tuple_element<__i, _Tp>::type;
00716 #endif
00717 
00718   /// Finds the size of a given tuple type.
00719   template<typename _Tp>
00720     struct tuple_size;
00721 
00722   // _GLIBCXX_RESOLVE_LIB_DEFECTS
00723   // 2313. tuple_size should always derive from integral_constant<size_t, N>
00724   template<typename _Tp>
00725     struct tuple_size<const _Tp>
00726     : public integral_constant<size_t, tuple_size<_Tp>::value> { };
00727 
00728   template<typename _Tp>
00729     struct tuple_size<volatile _Tp>
00730     : public integral_constant<size_t, tuple_size<_Tp>::value> { };
00731 
00732   template<typename _Tp>
00733     struct tuple_size<const volatile _Tp>
00734     : public integral_constant<size_t, tuple_size<_Tp>::value> { };
00735 
00736   /// class tuple_size
00737   template<typename... _Elements>
00738     struct tuple_size<tuple<_Elements...>>
00739     : public integral_constant<std::size_t, sizeof...(_Elements)> { };
00740 
00741   template<std::size_t __i, typename _Head, typename... _Tail>
00742     constexpr typename __add_ref<_Head>::type
00743     __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
00744     { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
00745 
00746   template<std::size_t __i, typename _Head, typename... _Tail>
00747     constexpr typename __add_c_ref<_Head>::type
00748     __get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
00749     { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
00750 
00751   /// Return a reference to the ith element of a tuple.
00752   template<std::size_t __i, typename... _Elements>
00753     constexpr typename __add_ref<
00754                       typename tuple_element<__i, tuple<_Elements...>>::type
00755                     >::type
00756     get(tuple<_Elements...>& __t) noexcept
00757     { return std::__get_helper<__i>(__t); }
00758 
00759   /// Return a const reference to the ith element of a const tuple.
00760   template<std::size_t __i, typename... _Elements>
00761     constexpr typename __add_c_ref<
00762                       typename tuple_element<__i, tuple<_Elements...>>::type
00763                     >::type
00764     get(const tuple<_Elements...>& __t) noexcept
00765     { return std::__get_helper<__i>(__t); }
00766 
00767   /// Return an rvalue reference to the ith element of a tuple rvalue.
00768   template<std::size_t __i, typename... _Elements>
00769     constexpr typename __add_r_ref<
00770                       typename tuple_element<__i, tuple<_Elements...>>::type
00771                     >::type
00772     get(tuple<_Elements...>&& __t) noexcept
00773     { return std::forward<typename tuple_element<__i,
00774     tuple<_Elements...>>::type&&>(get<__i>(__t)); }
00775 
00776 #if __cplusplus > 201103L
00777   template<typename _Head, size_t __i, typename... _Tail>
00778     constexpr typename __add_ref<_Head>::type
00779     __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
00780     { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
00781 
00782   template<typename _Head, size_t __i, typename... _Tail>
00783     constexpr typename __add_c_ref<_Head>::type
00784     __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
00785     { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
00786 
00787   /// Return a reference to the unique element of type _Tp of a tuple.
00788   template <typename _Tp, typename... _Types>
00789     constexpr _Tp&
00790     get(tuple<_Types...>& __t) noexcept
00791     { return std::__get_helper2<_Tp>(__t); }
00792 
00793   /// Return a reference to the unique element of type _Tp of a tuple rvalue.
00794   template <typename _Tp, typename... _Types>
00795     constexpr _Tp&&
00796     get(tuple<_Types...>&& __t) noexcept
00797     { return std::forward<_Tp&&>(std::__get_helper2<_Tp>(__t)); }
00798 
00799   /// Return a const reference to the unique element of type _Tp of a tuple.
00800   template <typename _Tp, typename... _Types>
00801     constexpr const _Tp&
00802     get(const tuple<_Types...>& __t) noexcept
00803     { return std::__get_helper2<_Tp>(__t); }
00804 #endif
00805 
00806 
00807   // This class helps construct the various comparison operations on tuples
00808   template<std::size_t __check_equal_size, std::size_t __i, std::size_t __j,
00809        typename _Tp, typename _Up>
00810     struct __tuple_compare;
00811 
00812   template<std::size_t __i, std::size_t __j, typename _Tp, typename _Up>
00813     struct __tuple_compare<0, __i, __j, _Tp, _Up>
00814     {
00815       static constexpr bool 
00816       __eq(const _Tp& __t, const _Up& __u)
00817       {
00818     return (get<__i>(__t) == get<__i>(__u) &&
00819         __tuple_compare<0, __i + 1, __j, _Tp, _Up>::__eq(__t, __u));
00820       }
00821      
00822       static constexpr bool 
00823       __less(const _Tp& __t, const _Up& __u)
00824       {
00825     return ((get<__i>(__t) < get<__i>(__u))
00826         || !(get<__i>(__u) < get<__i>(__t)) &&
00827         __tuple_compare<0, __i + 1, __j, _Tp, _Up>::__less(__t, __u));
00828       }
00829     };
00830 
00831   template<std::size_t __i, typename _Tp, typename _Up>
00832     struct __tuple_compare<0, __i, __i, _Tp, _Up>
00833     {
00834       static constexpr bool 
00835       __eq(const _Tp&, const _Up&) { return true; }
00836      
00837       static constexpr bool 
00838       __less(const _Tp&, const _Up&) { return false; }
00839     };
00840 
00841   template<typename... _TElements, typename... _UElements>
00842     constexpr bool
00843     operator==(const tuple<_TElements...>& __t,
00844            const tuple<_UElements...>& __u)
00845     {
00846       typedef tuple<_TElements...> _Tp;
00847       typedef tuple<_UElements...> _Up;
00848       return bool(__tuple_compare<tuple_size<_Tp>::value - tuple_size<_Up>::value,
00849           0, tuple_size<_Tp>::value, _Tp, _Up>::__eq(__t, __u));
00850     }
00851 
00852   template<typename... _TElements, typename... _UElements>
00853     constexpr bool
00854     operator<(const tuple<_TElements...>& __t,
00855           const tuple<_UElements...>& __u)
00856     {
00857       typedef tuple<_TElements...> _Tp;
00858       typedef tuple<_UElements...> _Up;
00859       return bool(__tuple_compare<tuple_size<_Tp>::value - tuple_size<_Up>::value,
00860           0, tuple_size<_Tp>::value, _Tp, _Up>::__less(__t, __u));
00861     }
00862 
00863   template<typename... _TElements, typename... _UElements>
00864     constexpr bool
00865     operator!=(const tuple<_TElements...>& __t,
00866            const tuple<_UElements...>& __u)
00867     { return !(__t == __u); }
00868 
00869   template<typename... _TElements, typename... _UElements>
00870     constexpr bool
00871     operator>(const tuple<_TElements...>& __t,
00872           const tuple<_UElements...>& __u)
00873     { return __u < __t; }
00874 
00875   template<typename... _TElements, typename... _UElements>
00876     constexpr bool
00877     operator<=(const tuple<_TElements...>& __t,
00878            const tuple<_UElements...>& __u)
00879     { return !(__u < __t); }
00880 
00881   template<typename... _TElements, typename... _UElements>
00882     constexpr bool
00883     operator>=(const tuple<_TElements...>& __t,
00884            const tuple<_UElements...>& __u)
00885     { return !(__t < __u); }
00886 
00887   // NB: DR 705.
00888   template<typename... _Elements>
00889     constexpr tuple<typename __decay_and_strip<_Elements>::__type...>
00890     make_tuple(_Elements&&... __args)
00891     {
00892       typedef tuple<typename __decay_and_strip<_Elements>::__type...>
00893     __result_type;
00894       return __result_type(std::forward<_Elements>(__args)...);
00895     }
00896 
00897   template<typename... _Elements>
00898     tuple<_Elements&&...>
00899     forward_as_tuple(_Elements&&... __args) noexcept
00900     { return tuple<_Elements&&...>(std::forward<_Elements>(__args)...); }
00901 
00902   template<typename>
00903     struct __is_tuple_like_impl : false_type
00904     { };
00905 
00906   template<typename... _Tps>
00907     struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
00908     { };
00909 
00910   template<typename _T1, typename _T2>
00911     struct __is_tuple_like_impl<pair<_T1, _T2>> : true_type
00912     { };
00913 
00914   template<typename _Tp, std::size_t _Nm>
00915     struct __is_tuple_like_impl<array<_Tp, _Nm>> : true_type
00916     { };
00917 
00918   // Internal type trait that allows us to sfinae-protect tuple_cat.
00919   template<typename _Tp>
00920     struct __is_tuple_like
00921     : public __is_tuple_like_impl<typename std::remove_cv
00922             <typename std::remove_reference<_Tp>::type>::type>::type
00923     { };
00924 
00925   template<std::size_t, typename, typename, std::size_t>
00926     struct __make_tuple_impl;
00927 
00928   template<std::size_t _Idx, typename _Tuple, typename... _Tp,
00929            std::size_t _Nm>
00930     struct __make_tuple_impl<_Idx, tuple<_Tp...>, _Tuple, _Nm>
00931     {
00932       typedef typename __make_tuple_impl<_Idx + 1, tuple<_Tp...,
00933     typename std::tuple_element<_Idx, _Tuple>::type>, _Tuple, _Nm>::__type
00934       __type;
00935     };
00936 
00937   template<std::size_t _Nm, typename _Tuple, typename... _Tp>
00938     struct __make_tuple_impl<_Nm, tuple<_Tp...>, _Tuple, _Nm>
00939     {
00940       typedef tuple<_Tp...> __type;
00941     };
00942 
00943   template<typename _Tuple>
00944     struct __do_make_tuple
00945     : public __make_tuple_impl<0, tuple<>, _Tuple,
00946                                std::tuple_size<_Tuple>::value>
00947     { };
00948 
00949   // Returns the std::tuple equivalent of a tuple-like type.
00950   template<typename _Tuple>
00951     struct __make_tuple
00952     : public __do_make_tuple<typename std::remove_cv
00953             <typename std::remove_reference<_Tuple>::type>::type>
00954     { };
00955 
00956   // Combines several std::tuple's into a single one.
00957   template<typename...>
00958     struct __combine_tuples;
00959 
00960   template<>
00961     struct __combine_tuples<>
00962     {
00963       typedef tuple<> __type;
00964     };
00965 
00966   template<typename... _Ts>
00967     struct __combine_tuples<tuple<_Ts...>>
00968     {
00969       typedef tuple<_Ts...> __type;
00970     };
00971 
00972   template<typename... _T1s, typename... _T2s, typename... _Rem>
00973     struct __combine_tuples<tuple<_T1s...>, tuple<_T2s...>, _Rem...>
00974     {
00975       typedef typename __combine_tuples<tuple<_T1s..., _T2s...>,
00976                     _Rem...>::__type __type;
00977     };
00978 
00979   // Computes the result type of tuple_cat given a set of tuple-like types.
00980   template<typename... _Tpls>
00981     struct __tuple_cat_result
00982     {
00983       typedef typename __combine_tuples
00984         <typename __make_tuple<_Tpls>::__type...>::__type __type;
00985     };
00986 
00987   // Helper to determine the index set for the first tuple-like
00988   // type of a given set.
00989   template<typename...>
00990     struct __make_1st_indices;
00991 
00992   template<>
00993     struct __make_1st_indices<>
00994     {
00995       typedef std::_Index_tuple<> __type;
00996     };
00997 
00998   template<typename _Tp, typename... _Tpls>
00999     struct __make_1st_indices<_Tp, _Tpls...>
01000     {
01001       typedef typename std::_Build_index_tuple<std::tuple_size<
01002     typename std::remove_reference<_Tp>::type>::value>::__type __type;
01003     };
01004 
01005   // Performs the actual concatenation by step-wise expanding tuple-like
01006   // objects into the elements,  which are finally forwarded into the
01007   // result tuple.
01008   template<typename _Ret, typename _Indices, typename... _Tpls>
01009     struct __tuple_concater;
01010 
01011   template<typename _Ret, std::size_t... _Is, typename _Tp, typename... _Tpls>
01012     struct __tuple_concater<_Ret, std::_Index_tuple<_Is...>, _Tp, _Tpls...>
01013     {
01014       template<typename... _Us>
01015         static constexpr _Ret
01016         _S_do(_Tp&& __tp, _Tpls&&... __tps, _Us&&... __us)
01017         {
01018       typedef typename __make_1st_indices<_Tpls...>::__type __idx;
01019       typedef __tuple_concater<_Ret, __idx, _Tpls...>      __next;
01020       return __next::_S_do(std::forward<_Tpls>(__tps)...,
01021                    std::forward<_Us>(__us)...,
01022                    std::get<_Is>(std::forward<_Tp>(__tp))...);
01023     }
01024     };
01025 
01026   template<typename _Ret>
01027     struct __tuple_concater<_Ret, std::_Index_tuple<>>
01028     {
01029       template<typename... _Us>
01030     static constexpr _Ret
01031     _S_do(_Us&&... __us)
01032         {
01033       return _Ret(std::forward<_Us>(__us)...);
01034     }
01035     };
01036 
01037   /// tuple_cat
01038   template<typename... _Tpls, typename = typename
01039            enable_if<__and_<__is_tuple_like<_Tpls>...>::value>::type>
01040     constexpr auto
01041     tuple_cat(_Tpls&&... __tpls)
01042     -> typename __tuple_cat_result<_Tpls...>::__type
01043     {
01044       typedef typename __tuple_cat_result<_Tpls...>::__type __ret;
01045       typedef typename __make_1st_indices<_Tpls...>::__type __idx;
01046       typedef __tuple_concater<__ret, __idx, _Tpls...> __concater;
01047       return __concater::_S_do(std::forward<_Tpls>(__tpls)...);
01048     }
01049 
01050   /// tie
01051   template<typename... _Elements>
01052     inline tuple<_Elements&...>
01053     tie(_Elements&... __args) noexcept
01054     { return tuple<_Elements&...>(__args...); }
01055 
01056   /// swap
01057   template<typename... _Elements>
01058     inline void 
01059     swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
01060     noexcept(noexcept(__x.swap(__y)))
01061     { __x.swap(__y); }
01062 
01063   // A class (and instance) which can be used in 'tie' when an element
01064   // of a tuple is not required
01065   struct _Swallow_assign
01066   {
01067     template<class _Tp>
01068       const _Swallow_assign&
01069       operator=(const _Tp&) const
01070       { return *this; }
01071   };
01072 
01073   const _Swallow_assign ignore{};
01074 
01075   /// Partial specialization for tuples
01076   template<typename... _Types, typename _Alloc>
01077     struct uses_allocator<tuple<_Types...>, _Alloc> : true_type { };
01078 
01079   // See stl_pair.h...
01080   template<class _T1, class _T2>
01081     template<typename... _Args1, typename... _Args2>
01082       inline
01083       pair<_T1, _T2>::
01084       pair(piecewise_construct_t,
01085        tuple<_Args1...> __first, tuple<_Args2...> __second)
01086       : pair(__first, __second,
01087          typename _Build_index_tuple<sizeof...(_Args1)>::__type(),
01088          typename _Build_index_tuple<sizeof...(_Args2)>::__type())
01089       { }
01090 
01091   template<class _T1, class _T2>
01092     template<typename... _Args1, std::size_t... _Indexes1,
01093              typename... _Args2, std::size_t... _Indexes2>
01094       inline
01095       pair<_T1, _T2>::
01096       pair(tuple<_Args1...>& __tuple1, tuple<_Args2...>& __tuple2,
01097        _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>)
01098       : first(std::forward<_Args1>(std::get<_Indexes1>(__tuple1))...),
01099         second(std::forward<_Args2>(std::get<_Indexes2>(__tuple2))...)
01100       { }
01101 
01102   /// @}
01103 
01104 _GLIBCXX_END_NAMESPACE_VERSION
01105 } // namespace std
01106 
01107 #endif // C++11
01108 
01109 #endif // _GLIBCXX_TUPLE