| // -*- C++ -*- | 
 | //===--------------------------- tuple ------------------------------------===// | 
 | // | 
 | //                     The LLVM Compiler Infrastructure | 
 | // | 
 | // This file is distributed under the University of Illinois Open Source | 
 | // License. See LICENSE.TXT for details. | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 |  | 
 | #ifndef _LIBCPP_TUPLE | 
 | #define _LIBCPP_TUPLE | 
 |  | 
 | /* | 
 |     tuple synopsis | 
 |  | 
 | namespace std | 
 | { | 
 |  | 
 | template <class... T> | 
 | class tuple { | 
 | public: | 
 |     constexpr tuple(); | 
 |     explicit tuple(const T&...); | 
 |     template <class... U> | 
 |         explicit tuple(U&&...); | 
 |     tuple(const tuple&) = default; | 
 |     tuple(tuple&&) = default; | 
 |     template <class... U> | 
 |         tuple(const tuple<U...>&); | 
 |     template <class... U> | 
 |         tuple(tuple<U...>&&); | 
 |     template <class U1, class U2> | 
 |         tuple(const pair<U1, U2>&); // iff sizeof...(T) == 2 | 
 |     template <class U1, class U2> | 
 |         tuple(pair<U1, U2>&&); // iff sizeof...(T) == 2 | 
 |  | 
 |     // allocator-extended constructors | 
 |     template <class Alloc> | 
 |         tuple(allocator_arg_t, const Alloc& a); | 
 |     template <class Alloc> | 
 |         tuple(allocator_arg_t, const Alloc& a, const T&...); | 
 |     template <class Alloc, class... U> | 
 |         tuple(allocator_arg_t, const Alloc& a, U&&...); | 
 |     template <class Alloc> | 
 |         tuple(allocator_arg_t, const Alloc& a, const tuple&); | 
 |     template <class Alloc> | 
 |         tuple(allocator_arg_t, const Alloc& a, tuple&&); | 
 |     template <class Alloc, class... U> | 
 |         tuple(allocator_arg_t, const Alloc& a, const tuple<U...>&); | 
 |     template <class Alloc, class... U> | 
 |         tuple(allocator_arg_t, const Alloc& a, tuple<U...>&&); | 
 |     template <class Alloc, class U1, class U2> | 
 |         tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&); | 
 |     template <class Alloc, class U1, class U2> | 
 |         tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&&); | 
 |  | 
 |     tuple& operator=(const tuple&); | 
 |     tuple& | 
 |         operator=(tuple&&) noexcept(AND(is_nothrow_move_assignable<T>::value ...)); | 
 |     template <class... U> | 
 |         tuple& operator=(const tuple<U...>&); | 
 |     template <class... U> | 
 |         tuple& operator=(tuple<U...>&&); | 
 |     template <class U1, class U2> | 
 |         tuple& operator=(const pair<U1, U2>&); // iff sizeof...(T) == 2 | 
 |     template <class U1, class U2> | 
 |         tuple& operator=(pair<U1, U2>&&); //iffsizeof...(T) == 2 | 
 |  | 
 |     void swap(tuple&) noexcept(AND(swap(declval<T&>(), declval<T&>())...)); | 
 | }; | 
 |  | 
 | const unspecified ignore; | 
 |  | 
 | template <class... T> tuple<V...>  make_tuple(T&&...); | 
 | template <class... T> tuple<ATypes...> forward_as_tuple(T&&...) noexcept; | 
 | template <class... T> tuple<T&...> tie(T&...) noexcept; | 
 | template <class... Tuples> tuple<CTypes...> tuple_cat(Tuples&&... tpls); | 
 |    | 
 | // 20.4.1.4, tuple helper classes: | 
 | template <class T> class tuple_size; // undefined | 
 | template <class... T> class tuple_size<tuple<T...>>; | 
 | template <intsize_t I, class T> class tuple_element; // undefined | 
 | template <intsize_t I, class... T> class tuple_element<I, tuple<T...>>; | 
 |  | 
 | // 20.4.1.5, element access: | 
 | template <intsize_t I, class... T> | 
 |     typename tuple_element<I, tuple<T...>>::type& | 
 |     get(tuple<T...>&) noexcept; | 
 | template <intsize_t I, class... T> | 
 |     typename tuple_element<I, tuple<T...>>::type const& | 
 |     get(const tuple<T...>&) noexcept; | 
 | template <intsize_t I, class... T> | 
 |     typename tuple_element<I, tuple<T...>>::type&& | 
 |     get(tuple<T...>&&) noexcept; | 
 |  | 
 | // 20.4.1.6, relational operators: | 
 | template<class... T, class... U> bool operator==(const tuple<T...>&, const tuple<U...>&); | 
 | template<class... T, class... U> bool operator<(const tuple<T...>&, const tuple<U...>&); | 
 | template<class... T, class... U> bool operator!=(const tuple<T...>&, const tuple<U...>&); | 
 | template<class... T, class... U> bool operator>(const tuple<T...>&, const tuple<U...>&); | 
 | template<class... T, class... U> bool operator<=(const tuple<T...>&, const tuple<U...>&); | 
 | template<class... T, class... U> bool operator>=(const tuple<T...>&, const tuple<U...>&); | 
 |  | 
 | template <class... Types, class Alloc> | 
 |   struct uses_allocator<tuple<Types...>, Alloc>; | 
 |  | 
 | template <class... Types> | 
 |   void | 
 |   swap(tuple<Types...>& x, tuple<Types...>& y) noexcept(noexcept(x.swap(y))); | 
 |  | 
 | }  // std | 
 |  | 
 | */ | 
 |  | 
 | #include <__config> | 
 | #include <__tuple> | 
 | #include <cstddef> | 
 | #include <type_traits> | 
 | #include <__functional_base> | 
 | #include <utility> | 
 |  | 
 | #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) | 
 | #pragma GCC system_header | 
 | #endif | 
 |  | 
 | _LIBCPP_BEGIN_NAMESPACE_STD | 
 |  | 
 | // allocator_arg_t | 
 |  | 
 | struct _LIBCPP_TYPE_VIS allocator_arg_t { }; | 
 |  | 
 | #if defined(_LIBCPP_HAS_NO_CONSTEXPR) || defined(_LIBCPP_BUILDING_MEMORY) | 
 | extern const allocator_arg_t allocator_arg; | 
 | #else | 
 | constexpr allocator_arg_t allocator_arg = allocator_arg_t(); | 
 | #endif | 
 |  | 
 | // uses_allocator | 
 |  | 
 | template <class _Tp> | 
 | struct __has_allocator_type | 
 | { | 
 | private: | 
 |     struct __two {char __lx; char __lxx;}; | 
 |     template <class _Up> static __two __test(...); | 
 |     template <class _Up> static char __test(typename _Up::allocator_type* = 0); | 
 | public: | 
 |     static const bool value = sizeof(__test<_Tp>(0)) == 1; | 
 | }; | 
 |  | 
 | template <class _Tp, class _Alloc, bool = __has_allocator_type<_Tp>::value> | 
 | struct __uses_allocator | 
 |     : public integral_constant<bool, | 
 |         is_convertible<_Alloc, typename _Tp::allocator_type>::value> | 
 | { | 
 | }; | 
 |  | 
 | template <class _Tp, class _Alloc> | 
 | struct __uses_allocator<_Tp, _Alloc, false> | 
 |     : public false_type | 
 | { | 
 | }; | 
 |  | 
 | template <class _Tp, class _Alloc> | 
 | struct _LIBCPP_TYPE_VIS uses_allocator | 
 |     : public __uses_allocator<_Tp, _Alloc> | 
 | { | 
 | }; | 
 |  | 
 | #ifndef _LIBCPP_HAS_NO_VARIADICS | 
 |  | 
 | // uses-allocator construction | 
 |  | 
 | template <class _Tp, class _Alloc, class ..._Args> | 
 | struct __uses_alloc_ctor_imp | 
 | { | 
 |     static const bool __ua = uses_allocator<_Tp, _Alloc>::value; | 
 |     static const bool __ic = | 
 |         is_constructible<_Tp, allocator_arg_t, _Alloc, _Args...>::value; | 
 |     static const int value = __ua ? 2 - __ic : 0; | 
 | }; | 
 |  | 
 | template <class _Tp, class _Alloc, class ..._Args> | 
 | struct __uses_alloc_ctor | 
 |     : integral_constant<int, __uses_alloc_ctor_imp<_Tp, _Alloc, _Args...>::value> | 
 |     {}; | 
 |  | 
 | #endif  // _LIBCPP_HAS_NO_VARIADICS | 
 |  | 
 | #ifndef _LIBCPP_HAS_NO_VARIADICS | 
 |  | 
 | // tuple_size | 
 |  | 
 | template <class ..._Tp> | 
 | class _LIBCPP_TYPE_VIS tuple_size<tuple<_Tp...> > | 
 |     : public integral_constant<size_t, sizeof...(_Tp)> | 
 | { | 
 | }; | 
 |  | 
 | // tuple_element | 
 |  | 
 | template <size_t _Ip, class ..._Tp> | 
 | class _LIBCPP_TYPE_VIS tuple_element<_Ip, tuple<_Tp...> > | 
 | { | 
 | public: | 
 |     typedef typename tuple_element<_Ip, __tuple_types<_Tp...> >::type type; | 
 | }; | 
 |  | 
 | // __tuple_leaf | 
 |  | 
 | template <size_t _Ip, class _Hp, bool=is_empty<_Hp>::value | 
 | #if __has_feature(is_final) | 
 |                                  && !__is_final(_Hp) | 
 | #endif | 
 |          > | 
 | class __tuple_leaf; | 
 |  | 
 | template <size_t _Ip, class _Hp, bool _Ep> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | void swap(__tuple_leaf<_Ip, _Hp, _Ep>& __x, __tuple_leaf<_Ip, _Hp, _Ep>& __y) | 
 |     _NOEXCEPT_(__is_nothrow_swappable<_Hp>::value) | 
 | { | 
 |     swap(__x.get(), __y.get()); | 
 | } | 
 |  | 
 | template <size_t _Ip, class _Hp, bool> | 
 | class __tuple_leaf | 
 | { | 
 |     _Hp value; | 
 |  | 
 |     __tuple_leaf& operator=(const __tuple_leaf&); | 
 | public: | 
 |     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __tuple_leaf() | 
 |              _NOEXCEPT_(is_nothrow_default_constructible<_Hp>::value) : value() | 
 |        {static_assert(!is_reference<_Hp>::value, | 
 |               "Attempted to default construct a reference element in a tuple");} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 0>, const _Alloc&) | 
 |             : value() | 
 |         {static_assert(!is_reference<_Hp>::value, | 
 |               "Attempted to default construct a reference element in a tuple");} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a) | 
 |             : value(allocator_arg_t(), __a) | 
 |         {static_assert(!is_reference<_Hp>::value, | 
 |               "Attempted to default construct a reference element in a tuple");} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) | 
 |             : value(__a) | 
 |         {static_assert(!is_reference<_Hp>::value, | 
 |               "Attempted to default construct a reference element in a tuple");} | 
 |  | 
 |     template <class _Tp, | 
 |               class = typename enable_if<is_constructible<_Hp, _Tp>::value>::type> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(_Tp&& __t) _NOEXCEPT_((is_nothrow_constructible<_Hp, _Tp>::value)) | 
 |             : value(_VSTD::forward<_Tp>(__t)) | 
 |         {static_assert(!is_reference<_Hp>::value || | 
 |                        (is_lvalue_reference<_Hp>::value && | 
 |                         (is_lvalue_reference<_Tp>::value || | 
 |                          is_same<typename remove_reference<_Tp>::type, | 
 |                                  reference_wrapper< | 
 |                                     typename remove_reference<_Hp>::type | 
 |                                  > | 
 |                                 >::value)) || | 
 |                         (is_rvalue_reference<_Hp>::value && | 
 |                          !is_lvalue_reference<_Tp>::value), | 
 |        "Attempted to construct a reference element in a tuple with an rvalue");} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t) | 
 |             : value(_VSTD::forward<_Tp>(__t)) | 
 |         {static_assert(!is_lvalue_reference<_Hp>::value || | 
 |                        (is_lvalue_reference<_Hp>::value && | 
 |                         (is_lvalue_reference<_Tp>::value || | 
 |                          is_same<typename remove_reference<_Tp>::type, | 
 |                                  reference_wrapper< | 
 |                                     typename remove_reference<_Hp>::type | 
 |                                  > | 
 |                                 >::value)), | 
 |        "Attempted to construct a reference element in a tuple with an rvalue");} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t) | 
 |             : value(allocator_arg_t(), __a, _VSTD::forward<_Tp>(__t)) | 
 |         {static_assert(!is_lvalue_reference<_Hp>::value || | 
 |                        (is_lvalue_reference<_Hp>::value && | 
 |                         (is_lvalue_reference<_Tp>::value || | 
 |                          is_same<typename remove_reference<_Tp>::type, | 
 |                                  reference_wrapper< | 
 |                                     typename remove_reference<_Hp>::type | 
 |                                  > | 
 |                                 >::value)), | 
 |        "Attempted to construct a reference element in a tuple with an rvalue");} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t) | 
 |             : value(_VSTD::forward<_Tp>(__t), __a) | 
 |         {static_assert(!is_lvalue_reference<_Hp>::value || | 
 |                        (is_lvalue_reference<_Hp>::value && | 
 |                         (is_lvalue_reference<_Tp>::value || | 
 |                          is_same<typename remove_reference<_Tp>::type, | 
 |                                  reference_wrapper< | 
 |                                     typename remove_reference<_Hp>::type | 
 |                                  > | 
 |                                 >::value)), | 
 |        "Attempted to construct a reference element in a tuple with an rvalue");} | 
 |  | 
 |     __tuple_leaf(const __tuple_leaf& __t) _NOEXCEPT_(is_nothrow_copy_constructible<_Hp>::value) | 
 |         : value(__t.get()) | 
 |         {static_assert(!is_rvalue_reference<_Hp>::value, "Can not copy a tuple with rvalue reference member");} | 
 |  | 
 |     template <class _Tp> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(const __tuple_leaf<_Ip, _Tp>& __t) | 
 |                            _NOEXCEPT_((is_nothrow_constructible<_Hp, const _Tp&>::value)) | 
 |             : value(__t.get()) {} | 
 |  | 
 |     template <class _Tp> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf& | 
 |         operator=(_Tp&& __t) _NOEXCEPT_((is_nothrow_assignable<_Hp&, _Tp>::value)) | 
 |         { | 
 |             value = _VSTD::forward<_Tp>(__t); | 
 |             return *this; | 
 |         } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     int swap(__tuple_leaf& __t) _NOEXCEPT_(__is_nothrow_swappable<__tuple_leaf>::value) | 
 |     { | 
 |         _VSTD::swap(*this, __t); | 
 |         return 0; | 
 |     } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY       _Hp& get()       _NOEXCEPT {return value;} | 
 |     _LIBCPP_INLINE_VISIBILITY const _Hp& get() const _NOEXCEPT {return value;} | 
 | }; | 
 |  | 
 | template <size_t _Ip, class _Hp> | 
 | class __tuple_leaf<_Ip, _Hp, true> | 
 |     : private _Hp | 
 | { | 
 |  | 
 |     __tuple_leaf& operator=(const __tuple_leaf&); | 
 | public: | 
 |     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __tuple_leaf() | 
 |              _NOEXCEPT_(is_nothrow_default_constructible<_Hp>::value) {} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 0>, const _Alloc&) {} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a) | 
 |             : _Hp(allocator_arg_t(), __a) {} | 
 |  | 
 |     template <class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) | 
 |             : _Hp(__a) {} | 
 |  | 
 |     template <class _Tp, | 
 |               class = typename enable_if<is_constructible<_Hp, _Tp>::value>::type> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(_Tp&& __t) _NOEXCEPT_((is_nothrow_constructible<_Hp, _Tp>::value)) | 
 |             : _Hp(_VSTD::forward<_Tp>(__t)) {} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t) | 
 |             : _Hp(_VSTD::forward<_Tp>(__t)) {} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t) | 
 |             : _Hp(allocator_arg_t(), __a, _VSTD::forward<_Tp>(__t)) {} | 
 |  | 
 |     template <class _Tp, class _Alloc> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t) | 
 |             : _Hp(_VSTD::forward<_Tp>(__t), __a) {} | 
 |  | 
 |     template <class _Tp> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit __tuple_leaf(const __tuple_leaf<_Ip, _Tp>& __t) | 
 |             _NOEXCEPT_((is_nothrow_constructible<_Hp, const _Tp&>::value)) | 
 |             : _Hp(__t.get()) {} | 
 |  | 
 |     template <class _Tp> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_leaf& | 
 |         operator=(_Tp&& __t) _NOEXCEPT_((is_nothrow_assignable<_Hp&, _Tp>::value)) | 
 |         { | 
 |             _Hp::operator=(_VSTD::forward<_Tp>(__t)); | 
 |             return *this; | 
 |         } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     int | 
 |     swap(__tuple_leaf& __t) _NOEXCEPT_(__is_nothrow_swappable<__tuple_leaf>::value) | 
 |     { | 
 |         _VSTD::swap(*this, __t); | 
 |         return 0; | 
 |     } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY       _Hp& get()       _NOEXCEPT {return static_cast<_Hp&>(*this);} | 
 |     _LIBCPP_INLINE_VISIBILITY const _Hp& get() const _NOEXCEPT {return static_cast<const _Hp&>(*this);} | 
 | }; | 
 |  | 
 | template <class ..._Tp> | 
 | _LIBCPP_INLINE_VISIBILITY | 
 | void __swallow(_Tp&&...) _NOEXCEPT {} | 
 |  | 
 | template <bool ...> struct __all; | 
 |  | 
 | template <> | 
 | struct __all<> | 
 | { | 
 |     static const bool value = true; | 
 | }; | 
 |  | 
 | template <bool _B0, bool ... _Bp> | 
 | struct __all<_B0, _Bp...> | 
 | { | 
 |     static const bool value = _B0 && __all<_Bp...>::value; | 
 | }; | 
 |  | 
 | // __tuple_impl | 
 |  | 
 | template<class _Indx, class ..._Tp> struct __tuple_impl; | 
 |  | 
 | template<size_t ..._Indx, class ..._Tp> | 
 | struct __tuple_impl<__tuple_indices<_Indx...>, _Tp...> | 
 |     : public __tuple_leaf<_Indx, _Tp>... | 
 | { | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     _LIBCPP_CONSTEXPR __tuple_impl() | 
 |         _NOEXCEPT_(__all<is_nothrow_default_constructible<_Tp>::value...>::value) {} | 
 |  | 
 |     template <size_t ..._Uf, class ..._Tf, | 
 |               size_t ..._Ul, class ..._Tl, class ..._Up> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit | 
 |         __tuple_impl(__tuple_indices<_Uf...>, __tuple_types<_Tf...>, | 
 |                      __tuple_indices<_Ul...>, __tuple_types<_Tl...>, | 
 |                      _Up&&... __u) | 
 |                      _NOEXCEPT_((__all<is_nothrow_constructible<_Tf, _Up>::value...>::value && | 
 |                                  __all<is_nothrow_default_constructible<_Tl>::value...>::value)) : | 
 |             __tuple_leaf<_Uf, _Tf>(_VSTD::forward<_Up>(__u))..., | 
 |             __tuple_leaf<_Ul, _Tl>()... | 
 |             {} | 
 |  | 
 |     template <class _Alloc, size_t ..._Uf, class ..._Tf, | 
 |               size_t ..._Ul, class ..._Tl, class ..._Up> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit | 
 |         __tuple_impl(allocator_arg_t, const _Alloc& __a, | 
 |                      __tuple_indices<_Uf...>, __tuple_types<_Tf...>, | 
 |                      __tuple_indices<_Ul...>, __tuple_types<_Tl...>, | 
 |                      _Up&&... __u) : | 
 |             __tuple_leaf<_Uf, _Tf>(__uses_alloc_ctor<_Tf, _Alloc, _Up>(), __a, | 
 |             _VSTD::forward<_Up>(__u))..., | 
 |             __tuple_leaf<_Ul, _Tl>(__uses_alloc_ctor<_Tl, _Alloc>(), __a)... | 
 |             {} | 
 |  | 
 |     template <class _Tuple, | 
 |               class = typename enable_if | 
 |                       < | 
 |                          __tuple_convertible<_Tuple, tuple<_Tp...> >::value | 
 |                       >::type | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_impl(_Tuple&& __t) _NOEXCEPT_((__all<is_nothrow_constructible<_Tp, typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>::value...>::value)) | 
 |             : __tuple_leaf<_Indx, _Tp>(_VSTD::forward<typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>(_VSTD::get<_Indx>(__t)))... | 
 |             {} | 
 |  | 
 |     template <class _Alloc, class _Tuple, | 
 |               class = typename enable_if | 
 |                       < | 
 |                          __tuple_convertible<_Tuple, tuple<_Tp...> >::value | 
 |                       >::type | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_impl(allocator_arg_t, const _Alloc& __a, _Tuple&& __t) | 
 |             : __tuple_leaf<_Indx, _Tp>(__uses_alloc_ctor<_Tp, _Alloc, typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>(), __a, | 
 |                                        _VSTD::forward<typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>(_VSTD::get<_Indx>(__t)))... | 
 |             {} | 
 |  | 
 |     template <class _Tuple> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         typename enable_if | 
 |         < | 
 |             __tuple_assignable<_Tuple, tuple<_Tp...> >::value, | 
 |             __tuple_impl& | 
 |         >::type | 
 |         operator=(_Tuple&& __t) _NOEXCEPT_((__all<is_nothrow_assignable<_Tp&, typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>::value...>::value)) | 
 |         { | 
 |             __swallow(__tuple_leaf<_Indx, _Tp>::operator=(_VSTD::forward<typename tuple_element<_Indx, | 
 |                                        typename __make_tuple_types<_Tuple>::type>::type>(_VSTD::get<_Indx>(__t)))...); | 
 |             return *this; | 
 |         } | 
 |  | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         __tuple_impl& | 
 |         operator=(const __tuple_impl& __t) _NOEXCEPT_((__all<is_nothrow_copy_assignable<_Tp>::value...>::value)) | 
 |         { | 
 |             __swallow(__tuple_leaf<_Indx, _Tp>::operator=(static_cast<const __tuple_leaf<_Indx, _Tp>&>(__t).get())...); | 
 |             return *this; | 
 |         } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     void swap(__tuple_impl& __t) | 
 |         _NOEXCEPT_(__all<__is_nothrow_swappable<_Tp>::value...>::value) | 
 |     { | 
 |         __swallow(__tuple_leaf<_Indx, _Tp>::swap(static_cast<__tuple_leaf<_Indx, _Tp>&>(__t))...); | 
 |     } | 
 | }; | 
 |  | 
 | template <class ..._Tp> | 
 | class _LIBCPP_TYPE_VIS tuple | 
 | { | 
 |     typedef __tuple_impl<typename __make_tuple_indices<sizeof...(_Tp)>::type, _Tp...> base; | 
 |  | 
 |     base base_; | 
 |  | 
 |     template <size_t _Jp, class ..._Up> friend | 
 |         typename tuple_element<_Jp, tuple<_Up...> >::type& get(tuple<_Up...>&) _NOEXCEPT; | 
 |     template <size_t _Jp, class ..._Up> friend | 
 |         const typename tuple_element<_Jp, tuple<_Up...> >::type& get(const tuple<_Up...>&) _NOEXCEPT; | 
 |     template <size_t _Jp, class ..._Up> friend | 
 |         typename tuple_element<_Jp, tuple<_Up...> >::type&& get(tuple<_Up...>&&) _NOEXCEPT; | 
 | public: | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     _LIBCPP_CONSTEXPR tuple() | 
 |         _NOEXCEPT_(__all<is_nothrow_default_constructible<_Tp>::value...>::value) {} | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     explicit tuple(const _Tp& ... __t) _NOEXCEPT_((__all<is_nothrow_copy_constructible<_Tp>::value...>::value))  | 
 |         : base_(typename __make_tuple_indices<sizeof...(_Tp)>::type(), | 
 |                 typename __make_tuple_types<tuple, sizeof...(_Tp)>::type(), | 
 |                 typename __make_tuple_indices<0>::type(), | 
 |                 typename __make_tuple_types<tuple, 0>::type(), | 
 |                 __t... | 
 |                ) {} | 
 |  | 
 |     template <class _Alloc> | 
 |       _LIBCPP_INLINE_VISIBILITY | 
 |       tuple(allocator_arg_t, const _Alloc& __a, const _Tp& ... __t) | 
 |         : base_(allocator_arg_t(), __a, | 
 |                 typename __make_tuple_indices<sizeof...(_Tp)>::type(), | 
 |                 typename __make_tuple_types<tuple, sizeof...(_Tp)>::type(), | 
 |                 typename __make_tuple_indices<0>::type(), | 
 |                 typename __make_tuple_types<tuple, 0>::type(), | 
 |                 __t... | 
 |                ) {} | 
 |  | 
 |     template <class ..._Up, | 
 |               typename enable_if | 
 |                       < | 
 |                          sizeof...(_Up) <= sizeof...(_Tp) && | 
 |                          __tuple_convertible | 
 |                          < | 
 |                             tuple<_Up...>, | 
 |                             typename __make_tuple_types<tuple, | 
 |                                      sizeof...(_Up) < sizeof...(_Tp) ? | 
 |                                         sizeof...(_Up) : | 
 |                                         sizeof...(_Tp)>::type | 
 |                          >::value, | 
 |                          bool | 
 |                       >::type = false | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(_Up&&... __u) | 
 |             _NOEXCEPT_(( | 
 |                 is_nothrow_constructible< | 
 |                     typename __make_tuple_indices<sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type, | 
 |                     _Up... | 
 |                 >::value | 
 |             )) | 
 |             : base_(typename __make_tuple_indices<sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     _VSTD::forward<_Up>(__u)...) {} | 
 |  | 
 |     template <class ..._Up, | 
 |               typename enable_if | 
 |                       < | 
 |                          sizeof...(_Up) <= sizeof...(_Tp) && | 
 |                          __tuple_constructible | 
 |                          < | 
 |                             tuple<_Up...>, | 
 |                             typename __make_tuple_types<tuple, | 
 |                                      sizeof...(_Up) < sizeof...(_Tp) ? | 
 |                                         sizeof...(_Up) : | 
 |                                         sizeof...(_Tp)>::type | 
 |                          >::value && | 
 |                          !__tuple_convertible | 
 |                          < | 
 |                             tuple<_Up...>, | 
 |                             typename __make_tuple_types<tuple, | 
 |                                      sizeof...(_Up) < sizeof...(_Tp) ? | 
 |                                         sizeof...(_Up) : | 
 |                                         sizeof...(_Tp)>::type | 
 |                          >::value, | 
 |                          bool | 
 |                       >::type =false | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit | 
 |         tuple(_Up&&... __u) | 
 |             _NOEXCEPT_(( | 
 |                 is_nothrow_constructible< | 
 |                     typename __make_tuple_indices<sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type, | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type, | 
 |                     _Up... | 
 |                 >::value | 
 |             )) | 
 |             : base_(typename __make_tuple_indices<sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     _VSTD::forward<_Up>(__u)...) {} | 
 |  | 
 |     template <class _Alloc, class ..._Up, | 
 |               class = typename enable_if | 
 |                       < | 
 |                          sizeof...(_Up) <= sizeof...(_Tp) && | 
 |                          __tuple_convertible | 
 |                          < | 
 |                             tuple<_Up...>, | 
 |                             typename __make_tuple_types<tuple, | 
 |                                      sizeof...(_Up) < sizeof...(_Tp) ? | 
 |                                         sizeof...(_Up) : | 
 |                                         sizeof...(_Tp)>::type | 
 |                          >::value | 
 |                       >::type | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(allocator_arg_t, const _Alloc& __a, _Up&&... __u) | 
 |             : base_(allocator_arg_t(), __a, | 
 |                     typename __make_tuple_indices<sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_indices<sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     typename __make_tuple_types<tuple, sizeof...(_Tp), sizeof...(_Up)>::type(), | 
 |                     _VSTD::forward<_Up>(__u)...) {} | 
 |  | 
 |     template <class _Tuple, | 
 |               typename enable_if | 
 |                       < | 
 |                          __tuple_convertible<_Tuple, tuple>::value, | 
 |                          bool | 
 |                       >::type = false | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(_Tuple&& __t) _NOEXCEPT_((is_nothrow_constructible<base, _Tuple>::value)) | 
 |             : base_(_VSTD::forward<_Tuple>(__t)) {} | 
 |  | 
 |     template <class _Tuple, | 
 |               typename enable_if | 
 |                       < | 
 |                          __tuple_constructible<_Tuple, tuple>::value && | 
 |                          !__tuple_convertible<_Tuple, tuple>::value, | 
 |                          bool | 
 |                       >::type = false | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         explicit | 
 |         tuple(_Tuple&& __t) _NOEXCEPT_((is_nothrow_constructible<base, _Tuple>::value)) | 
 |             : base_(_VSTD::forward<_Tuple>(__t)) {} | 
 |  | 
 |     template <class _Alloc, class _Tuple, | 
 |               class = typename enable_if | 
 |                       < | 
 |                          __tuple_convertible<_Tuple, tuple>::value | 
 |                       >::type | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(allocator_arg_t, const _Alloc& __a, _Tuple&& __t) | 
 |             : base_(allocator_arg_t(), __a, _VSTD::forward<_Tuple>(__t)) {} | 
 |  | 
 |     template <class _Tuple, | 
 |               class = typename enable_if | 
 |                       < | 
 |                          __tuple_assignable<_Tuple, tuple>::value | 
 |                       >::type | 
 |              > | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         tuple& | 
 |         operator=(_Tuple&& __t) _NOEXCEPT_((is_nothrow_assignable<base&, _Tuple>::value)) | 
 |         { | 
 |             base_.operator=(_VSTD::forward<_Tuple>(__t)); | 
 |             return *this; | 
 |         } | 
 |  | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     void swap(tuple& __t) _NOEXCEPT_(__all<__is_nothrow_swappable<_Tp>::value...>::value) | 
 |         {base_.swap(__t.base_);} | 
 | }; | 
 |  | 
 | template <> | 
 | class _LIBCPP_TYPE_VIS tuple<> | 
 | { | 
 | public: | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     _LIBCPP_CONSTEXPR tuple() _NOEXCEPT {} | 
 |     template <class _Alloc> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(allocator_arg_t, const _Alloc&) _NOEXCEPT {} | 
 |     template <class _Alloc> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(allocator_arg_t, const _Alloc&, const tuple&) _NOEXCEPT {} | 
 |     template <class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(array<_Up, 0>) _NOEXCEPT {} | 
 |     template <class _Alloc, class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |         tuple(allocator_arg_t, const _Alloc&, array<_Up, 0>) _NOEXCEPT {} | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     void swap(tuple&) _NOEXCEPT {} | 
 | }; | 
 |  | 
 | template <class ..._Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | typename enable_if | 
 | < | 
 |     __all<__is_swappable<_Tp>::value...>::value, | 
 |     void | 
 | >::type | 
 | swap(tuple<_Tp...>& __t, tuple<_Tp...>& __u) | 
 |                  _NOEXCEPT_(__all<__is_nothrow_swappable<_Tp>::value...>::value) | 
 |     {__t.swap(__u);} | 
 |  | 
 | // get | 
 |  | 
 | template <size_t _Ip, class ..._Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | typename tuple_element<_Ip, tuple<_Tp...> >::type& | 
 | get(tuple<_Tp...>& __t) _NOEXCEPT | 
 | { | 
 |     typedef typename tuple_element<_Ip, tuple<_Tp...> >::type type; | 
 |     return static_cast<__tuple_leaf<_Ip, type>&>(__t.base_).get(); | 
 | } | 
 |  | 
 | template <size_t _Ip, class ..._Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | const typename tuple_element<_Ip, tuple<_Tp...> >::type& | 
 | get(const tuple<_Tp...>& __t) _NOEXCEPT | 
 | { | 
 |     typedef typename tuple_element<_Ip, tuple<_Tp...> >::type type; | 
 |     return static_cast<const __tuple_leaf<_Ip, type>&>(__t.base_).get(); | 
 | } | 
 |  | 
 | template <size_t _Ip, class ..._Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | typename tuple_element<_Ip, tuple<_Tp...> >::type&& | 
 | get(tuple<_Tp...>&& __t) _NOEXCEPT | 
 | { | 
 |     typedef typename tuple_element<_Ip, tuple<_Tp...> >::type type; | 
 |     return static_cast<type&&>( | 
 |              static_cast<__tuple_leaf<_Ip, type>&&>(__t.base_).get()); | 
 | } | 
 |  | 
 | // tie | 
 |  | 
 | template <class ..._Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | tuple<_Tp&...> | 
 | tie(_Tp&... __t) _NOEXCEPT | 
 | { | 
 |     return tuple<_Tp&...>(__t...); | 
 | } | 
 |  | 
 | template <class _Up> | 
 | struct __ignore_t | 
 | { | 
 |     template <class _Tp> | 
 |         _LIBCPP_INLINE_VISIBILITY | 
 |         const __ignore_t& operator=(_Tp&&) const {return *this;} | 
 | }; | 
 |  | 
 | namespace { const __ignore_t<unsigned char> ignore = __ignore_t<unsigned char>(); } | 
 |  | 
 | template <class _Tp> class _LIBCPP_TYPE_VIS reference_wrapper; | 
 |  | 
 | template <class _Tp> | 
 | struct ___make_tuple_return | 
 | { | 
 |     typedef _Tp type; | 
 | }; | 
 |  | 
 | template <class _Tp> | 
 | struct ___make_tuple_return<reference_wrapper<_Tp> > | 
 | { | 
 |     typedef _Tp& type; | 
 | }; | 
 |  | 
 | template <class _Tp> | 
 | struct __make_tuple_return | 
 | { | 
 |     typedef typename ___make_tuple_return<typename decay<_Tp>::type>::type type; | 
 | }; | 
 |  | 
 | template <class... _Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | tuple<typename __make_tuple_return<_Tp>::type...> | 
 | make_tuple(_Tp&&... __t) | 
 | { | 
 |     return tuple<typename __make_tuple_return<_Tp>::type...>(_VSTD::forward<_Tp>(__t)...); | 
 | } | 
 |  | 
 | template <class... _Tp> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | tuple<_Tp&&...> | 
 | forward_as_tuple(_Tp&&... __t) _NOEXCEPT | 
 | { | 
 |     return tuple<_Tp&&...>(_VSTD::forward<_Tp>(__t)...); | 
 | } | 
 |  | 
 | template <size_t _Ip> | 
 | struct __tuple_equal | 
 | { | 
 |     template <class _Tp, class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     bool operator()(const _Tp& __x, const _Up& __y) | 
 |     { | 
 |         return __tuple_equal<_Ip - 1>()(__x, __y) && get<_Ip-1>(__x) == get<_Ip-1>(__y); | 
 |     } | 
 | }; | 
 |  | 
 | template <> | 
 | struct __tuple_equal<0> | 
 | { | 
 |     template <class _Tp, class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     bool operator()(const _Tp&, const _Up&) | 
 |     { | 
 |         return true; | 
 |     } | 
 | }; | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator==(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return __tuple_equal<sizeof...(_Tp)>()(__x, __y); | 
 | } | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator!=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return !(__x == __y); | 
 | } | 
 |  | 
 | template <size_t _Ip> | 
 | struct __tuple_less | 
 | { | 
 |     template <class _Tp, class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     bool operator()(const _Tp& __x, const _Up& __y) | 
 |     { | 
 |         return __tuple_less<_Ip-1>()(__x, __y) || | 
 |              (!__tuple_less<_Ip-1>()(__y, __x) && get<_Ip-1>(__x) < get<_Ip-1>(__y)); | 
 |     } | 
 | }; | 
 |  | 
 | template <> | 
 | struct __tuple_less<0> | 
 | { | 
 |     template <class _Tp, class _Up> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     bool operator()(const _Tp&, const _Up&) | 
 |     { | 
 |         return false; | 
 |     } | 
 | }; | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator<(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return __tuple_less<sizeof...(_Tp)>()(__x, __y); | 
 | } | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator>(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return __y < __x; | 
 | } | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator>=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return !(__x < __y); | 
 | } | 
 |  | 
 | template <class ..._Tp, class ..._Up> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | bool | 
 | operator<=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) | 
 | { | 
 |     return !(__y < __x); | 
 | } | 
 |  | 
 | // tuple_cat | 
 |  | 
 | template <class _Tp, class _Up> struct __tuple_cat_type; | 
 |  | 
 | template <class ..._Ttypes, class ..._Utypes> | 
 | struct __tuple_cat_type<tuple<_Ttypes...>, __tuple_types<_Utypes...> > | 
 | { | 
 |     typedef tuple<_Ttypes..., _Utypes...> type; | 
 | }; | 
 |  | 
 | template <class _ResultTuple, bool _Is_Tuple0TupleLike, class ..._Tuples> | 
 | struct __tuple_cat_return_1 | 
 | { | 
 | }; | 
 |  | 
 | template <class ..._Types, class _Tuple0> | 
 | struct __tuple_cat_return_1<tuple<_Types...>, true, _Tuple0> | 
 | { | 
 |     typedef typename __tuple_cat_type<tuple<_Types...>, | 
 |             typename __make_tuple_types<typename remove_reference<_Tuple0>::type>::type>::type | 
 |                                                                            type; | 
 | }; | 
 |  | 
 | template <class ..._Types, class _Tuple0, class _Tuple1, class ..._Tuples> | 
 | struct __tuple_cat_return_1<tuple<_Types...>, true, _Tuple0, _Tuple1, _Tuples...> | 
 |     : public __tuple_cat_return_1< | 
 |                  typename __tuple_cat_type< | 
 |                      tuple<_Types...>, | 
 |                      typename __make_tuple_types<typename remove_reference<_Tuple0>::type>::type | 
 |                  >::type, | 
 |                  __tuple_like<typename remove_reference<_Tuple1>::type>::value, | 
 |                  _Tuple1, _Tuples...> | 
 | { | 
 | }; | 
 |  | 
 | template <class ..._Tuples> struct __tuple_cat_return; | 
 |  | 
 | template <class _Tuple0, class ..._Tuples> | 
 | struct __tuple_cat_return<_Tuple0, _Tuples...> | 
 |     : public __tuple_cat_return_1<tuple<>, | 
 |          __tuple_like<typename remove_reference<_Tuple0>::type>::value, _Tuple0, | 
 |                                                                      _Tuples...> | 
 | { | 
 | }; | 
 |  | 
 | template <> | 
 | struct __tuple_cat_return<> | 
 | { | 
 |     typedef tuple<> type; | 
 | }; | 
 |  | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | tuple<> | 
 | tuple_cat() | 
 | { | 
 |     return tuple<>(); | 
 | } | 
 |  | 
 | template <class _Rp, class _Indices, class _Tuple0, class ..._Tuples> | 
 | struct __tuple_cat_return_ref_imp; | 
 |  | 
 | template <class ..._Types, size_t ..._I0, class _Tuple0> | 
 | struct __tuple_cat_return_ref_imp<tuple<_Types...>, __tuple_indices<_I0...>, _Tuple0> | 
 | { | 
 |     typedef typename remove_reference<_Tuple0>::type _T0; | 
 |     typedef tuple<_Types..., typename __apply_cv<_Tuple0, | 
 |                           typename tuple_element<_I0, _T0>::type>::type&&...> type; | 
 | }; | 
 |  | 
 | template <class ..._Types, size_t ..._I0, class _Tuple0, class _Tuple1, class ..._Tuples> | 
 | struct __tuple_cat_return_ref_imp<tuple<_Types...>, __tuple_indices<_I0...>, | 
 |                                   _Tuple0, _Tuple1, _Tuples...> | 
 |     : public __tuple_cat_return_ref_imp< | 
 |          tuple<_Types..., typename __apply_cv<_Tuple0, | 
 |                typename tuple_element<_I0, | 
 |                   typename remove_reference<_Tuple0>::type>::type>::type&&...>, | 
 |          typename __make_tuple_indices<tuple_size<typename | 
 |                                  remove_reference<_Tuple1>::type>::value>::type, | 
 |          _Tuple1, _Tuples...> | 
 | { | 
 | }; | 
 |  | 
 | template <class _Tuple0, class ..._Tuples> | 
 | struct __tuple_cat_return_ref | 
 |     : public __tuple_cat_return_ref_imp<tuple<>, | 
 |                typename __make_tuple_indices< | 
 |                         tuple_size<typename remove_reference<_Tuple0>::type>::value | 
 |                >::type, _Tuple0, _Tuples...> | 
 | { | 
 | }; | 
 |  | 
 | template <class _Types, class _I0, class _J0> | 
 | struct __tuple_cat; | 
 |  | 
 | template <class ..._Types, size_t ..._I0, size_t ..._J0> | 
 | struct __tuple_cat<tuple<_Types...>, __tuple_indices<_I0...>, __tuple_indices<_J0...> > | 
 | { | 
 |     template <class _Tuple0> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&>::type | 
 |     operator()(tuple<_Types...> __t, _Tuple0&& __t0) | 
 |     { | 
 |         return _VSTD::forward_as_tuple(_VSTD::forward<_Types>(get<_I0>(__t))..., | 
 |                                       get<_J0>(_VSTD::forward<_Tuple0>(__t0))...); | 
 |     } | 
 |  | 
 |     template <class _Tuple0, class _Tuple1, class ..._Tuples> | 
 |     _LIBCPP_INLINE_VISIBILITY | 
 |     typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&, _Tuple1&&, _Tuples&&...>::type | 
 |     operator()(tuple<_Types...> __t, _Tuple0&& __t0, _Tuple1&& __t1, _Tuples&& ...__tpls) | 
 |     { | 
 |         typedef typename remove_reference<_Tuple0>::type _T0; | 
 |         typedef typename remove_reference<_Tuple1>::type _T1; | 
 |         return __tuple_cat< | 
 |            tuple<_Types..., typename __apply_cv<_Tuple0, typename tuple_element<_J0, _T0>::type>::type&&...>, | 
 |            typename __make_tuple_indices<sizeof ...(_Types) + tuple_size<_T0>::value>::type, | 
 |            typename __make_tuple_indices<tuple_size<_T1>::value>::type>() | 
 |                            (_VSTD::forward_as_tuple( | 
 |                               _VSTD::forward<_Types>(get<_I0>(__t))..., | 
 |                               get<_J0>(_VSTD::forward<_Tuple0>(__t0))... | 
 |                             ), | 
 |                             _VSTD::forward<_Tuple1>(__t1), | 
 |                             _VSTD::forward<_Tuples>(__tpls)...); | 
 |     } | 
 | }; | 
 |  | 
 | template <class _Tuple0, class... _Tuples> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | typename __tuple_cat_return<_Tuple0, _Tuples...>::type | 
 | tuple_cat(_Tuple0&& __t0, _Tuples&&... __tpls) | 
 | { | 
 |     typedef typename remove_reference<_Tuple0>::type _T0; | 
 |     return __tuple_cat<tuple<>, __tuple_indices<>, | 
 |                   typename __make_tuple_indices<tuple_size<_T0>::value>::type>() | 
 |                   (tuple<>(), _VSTD::forward<_Tuple0>(__t0), | 
 |                                             _VSTD::forward<_Tuples>(__tpls)...); | 
 | } | 
 |  | 
 | template <class ..._Tp, class _Alloc> | 
 | struct _LIBCPP_TYPE_VIS uses_allocator<tuple<_Tp...>, _Alloc> | 
 |     : true_type {}; | 
 |  | 
 | template <class _T1, class _T2> | 
 | template <class... _Args1, class... _Args2, size_t ..._I1, size_t ..._I2> | 
 | inline _LIBCPP_INLINE_VISIBILITY | 
 | pair<_T1, _T2>::pair(piecewise_construct_t, | 
 |                      tuple<_Args1...>& __first_args, tuple<_Args2...>& __second_args, | 
 |                      __tuple_indices<_I1...>, __tuple_indices<_I2...>) | 
 |     :  first(_VSTD::forward<_Args1>(get<_I1>( __first_args))...), | 
 |       second(_VSTD::forward<_Args2>(get<_I2>(__second_args))...) | 
 | { | 
 | } | 
 |  | 
 | #endif  // _LIBCPP_HAS_NO_VARIADICS | 
 |  | 
 | _LIBCPP_END_NAMESPACE_STD | 
 |  | 
 | #endif  // _LIBCPP_TUPLE |