rc3/include/__tuple - third_party/libcxx - Git at Google

 // -*- C++ -*-
 //===----------------------------------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is dual licensed under the MIT and the University of Illinois Open
 // Source Licenses. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//

 #ifndef _LIBCPP___TUPLE
 #define _LIBCPP___TUPLE

 #include <__config>
 #include <cstddef>
 #include <type_traits>

 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif

 #ifdef _LIBCPP_HAS_NO_VARIADICS

 #include <__tuple_03>

 #else  // _LIBCPP_HAS_NO_VARIADICS

 _LIBCPP_BEGIN_NAMESPACE_STD

 template <class _Tp> class _LIBCPP_TYPE_VIS tuple_size;

 template <class _Tp>
 class _LIBCPP_TYPE_VIS tuple_size<const _Tp>
     : public tuple_size<_Tp> {};

 template <class _Tp>
 class _LIBCPP_TYPE_VIS tuple_size<volatile _Tp>
     : public tuple_size<_Tp> {};

 template <class _Tp>
 class _LIBCPP_TYPE_VIS tuple_size<const volatile _Tp>
     : public tuple_size<_Tp> {};

 template <size_t _Ip, class _Tp> class _LIBCPP_TYPE_VIS tuple_element;

 template <size_t _Ip, class _Tp>
 class _LIBCPP_TYPE_VIS tuple_element<_Ip, const _Tp>
 {
 public:
     typedef typename add_const<typename tuple_element<_Ip, _Tp>::type>::type type;
 };

 template <size_t _Ip, class _Tp>
 class _LIBCPP_TYPE_VIS tuple_element<_Ip, volatile _Tp>
 {
 public:
     typedef typename add_volatile<typename tuple_element<_Ip, _Tp>::type>::type type;
 };

 template <size_t _Ip, class _Tp>
 class _LIBCPP_TYPE_VIS tuple_element<_Ip, const volatile _Tp>
 {
 public:
     typedef typename add_cv<typename tuple_element<_Ip, _Tp>::type>::type type;
 };

 template <class ..._Tp> class _LIBCPP_TYPE_VIS tuple;
 template <class _T1, class _T2> struct _LIBCPP_TYPE_VIS pair;
 template <class _Tp, size_t _Size> struct _LIBCPP_TYPE_VIS array;

 template <class _Tp> struct __tuple_like : false_type {};

 template <class _Tp> struct __tuple_like<const _Tp> : public __tuple_like<_Tp> {};
 template <class _Tp> struct __tuple_like<volatile _Tp> : public __tuple_like<_Tp> {};
 template <class _Tp> struct __tuple_like<const volatile _Tp> : public __tuple_like<_Tp> {};

 template <class... _Tp> struct __tuple_like<tuple<_Tp...> > : true_type {};
 template <class _T1, class _T2> struct __tuple_like<pair<_T1, _T2> > : true_type {};
 template <class _Tp, size_t _Size> struct __tuple_like<array<_Tp, _Size> > : true_type {};

 template <size_t _Ip, class ..._Tp>
 _LIBCPP_INLINE_VISIBILITY
 typename tuple_element<_Ip, tuple<_Tp...> >::type&
 get(tuple<_Tp...>&) _NOEXCEPT;

 template <size_t _Ip, class ..._Tp>
 _LIBCPP_INLINE_VISIBILITY
 const typename tuple_element<_Ip, tuple<_Tp...> >::type&
 get(const tuple<_Tp...>&) _NOEXCEPT;

 template <size_t _Ip, class ..._Tp>
 _LIBCPP_INLINE_VISIBILITY
 typename tuple_element<_Ip, tuple<_Tp...> >::type&&
 get(tuple<_Tp...>&&) _NOEXCEPT;

 template <size_t _Ip, class _T1, class _T2>
 _LIBCPP_INLINE_VISIBILITY
 typename tuple_element<_Ip, pair<_T1, _T2> >::type&
 get(pair<_T1, _T2>&) _NOEXCEPT;

 template <size_t _Ip, class _T1, class _T2>
 _LIBCPP_INLINE_VISIBILITY
 const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
 get(const pair<_T1, _T2>&) _NOEXCEPT;

 template <size_t _Ip, class _T1, class _T2>
 _LIBCPP_INLINE_VISIBILITY
 typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
 get(pair<_T1, _T2>&&) _NOEXCEPT;

 template <size_t _Ip, class _Tp, size_t _Size>
 _LIBCPP_INLINE_VISIBILITY
 _Tp&
 get(array<_Tp, _Size>&) _NOEXCEPT;

 template <size_t _Ip, class _Tp, size_t _Size>
 _LIBCPP_INLINE_VISIBILITY
 const _Tp&
 get(const array<_Tp, _Size>&) _NOEXCEPT;

 template <size_t _Ip, class _Tp, size_t _Size>
 _LIBCPP_INLINE_VISIBILITY
 _Tp&&
 get(array<_Tp, _Size>&&) _NOEXCEPT;

 // __make_tuple_indices

 template <size_t...> struct __tuple_indices {};

 template <size_t _Sp, class _IntTuple, size_t _Ep>
 struct __make_indices_imp;

 template <size_t _Sp, size_t ..._Indices, size_t _Ep>
 struct __make_indices_imp<_Sp, __tuple_indices<_Indices...>, _Ep>
 {
     typedef typename __make_indices_imp<_Sp+1, __tuple_indices<_Indices..., _Sp>, _Ep>::type type;
 };

 template <size_t _Ep, size_t ..._Indices>
 struct __make_indices_imp<_Ep, __tuple_indices<_Indices...>, _Ep>
 {
     typedef __tuple_indices<_Indices...> type;
 };

 template <size_t _Ep, size_t _Sp = 0>
 struct __make_tuple_indices
 {
     static_assert(_Sp <= _Ep, "__make_tuple_indices input error");
     typedef typename __make_indices_imp<_Sp, __tuple_indices<>, _Ep>::type type;
 };

 // __tuple_types

 template <class ..._Tp> struct __tuple_types {};

 template <size_t _Ip>
 class _LIBCPP_TYPE_VIS tuple_element<_Ip, __tuple_types<> >
 {
 public:
     static_assert(_Ip == 0, "tuple_element index out of range");
     static_assert(_Ip != 0, "tuple_element index out of range");
 };

 template <class _Hp, class ..._Tp>
 class _LIBCPP_TYPE_VIS tuple_element<0, __tuple_types<_Hp, _Tp...> >
 {
 public:
     typedef _Hp type;
 };

 template <size_t _Ip, class _Hp, class ..._Tp>
 class _LIBCPP_TYPE_VIS tuple_element<_Ip, __tuple_types<_Hp, _Tp...> >
 {
 public:
     typedef typename tuple_element<_Ip-1, __tuple_types<_Tp...> >::type type;
 };

 template <class ..._Tp>
 class _LIBCPP_TYPE_VIS tuple_size<__tuple_types<_Tp...> >
     : public integral_constant<size_t, sizeof...(_Tp)>
 {
 };

 template <class... _Tp> struct __tuple_like<__tuple_types<_Tp...> > : true_type {};

 // __make_tuple_types

 // __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
 // __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
 // _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>.  If _Tuple is a
 // lvalue_reference type, then __tuple_types<_Types&...> is the result.

 template <class _TupleTypes, class _Tp, size_t _Sp, size_t _Ep>
 struct __make_tuple_types_imp;

 template <class ..._Types, class _Tp, size_t _Sp, size_t _Ep>
 struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Sp, _Ep>
 {
     typedef typename remove_reference<_Tp>::type _Tpr;
     typedef typename __make_tuple_types_imp<__tuple_types<_Types...,
                                             typename conditional<is_lvalue_reference<_Tp>::value,
                                                 typename tuple_element<_Sp, _Tpr>::type&,
                                                 typename tuple_element<_Sp, _Tpr>::type>::type>,
                                             _Tp, _Sp+1, _Ep>::type type;
 };

 template <class ..._Types, class _Tp, size_t _Ep>
 struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Ep, _Ep>
 {
     typedef __tuple_types<_Types...> type;
 };

 template <class _Tp, size_t _Ep = tuple_size<typename remove_reference<_Tp>::type>::value, size_t _Sp = 0>
 struct __make_tuple_types
 {
     static_assert(_Sp <= _Ep, "__make_tuple_types input error");
     typedef typename __make_tuple_types_imp<__tuple_types<>, _Tp, _Sp, _Ep>::type type;
 };

 // __tuple_convertible

 template <bool, class _Tp, class _Up>
 struct __tuple_convertible_imp : public false_type {};

 template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
 struct __tuple_convertible_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
     : public integral_constant<bool,
                                is_convertible<_Tp0, _Up0>::value &&
                                __tuple_convertible_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

 template <>
 struct __tuple_convertible_imp<true, __tuple_types<>, __tuple_types<> >
     : public true_type {};

 template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
                                 bool = __tuple_like<_Up>::value>
 struct __tuple_convertible
     : public false_type {};

 template <class _Tp, class _Up>
 struct __tuple_convertible<_Tp, _Up, true, true>
     : public __tuple_convertible_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
                                      tuple_size<_Up>::value,
              typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
 {};

 // __tuple_constructible

 template <bool, class _Tp, class _Up>
 struct __tuple_constructible_imp : public false_type {};

 template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
 struct __tuple_constructible_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
     : public integral_constant<bool,
                                is_constructible<_Up0, _Tp0>::value &&
                                __tuple_constructible_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

 template <>
 struct __tuple_constructible_imp<true, __tuple_types<>, __tuple_types<> >
     : public true_type {};

 template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
                                 bool = __tuple_like<_Up>::value>
 struct __tuple_constructible
     : public false_type {};

 template <class _Tp, class _Up>
 struct __tuple_constructible<_Tp, _Up, true, true>
     : public __tuple_constructible_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
                                      tuple_size<_Up>::value,
              typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
 {};

 // __tuple_assignable

 template <bool, class _Tp, class _Up>
 struct __tuple_assignable_imp : public false_type {};

 template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
 struct __tuple_assignable_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
     : public integral_constant<bool,
                                is_assignable<_Up0&, _Tp0>::value &&
                                __tuple_assignable_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

 template <>
 struct __tuple_assignable_imp<true, __tuple_types<>, __tuple_types<> >
     : public true_type {};

 template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
                                 bool = __tuple_like<_Up>::value>
 struct __tuple_assignable
     : public false_type {};

 template <class _Tp, class _Up>
 struct __tuple_assignable<_Tp, _Up, true, true>
     : public __tuple_assignable_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
                                     tuple_size<_Up>::value,
              typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
 {};

 _LIBCPP_END_NAMESPACE_STD

 #endif  // _LIBCPP_HAS_NO_VARIADICS

 #endif  // _LIBCPP___TUPLE
	// -- C++ --
	//===----------------------------------------------------------------------===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is dual licensed under the MIT and the University of Illinois Open
	// Source Licenses. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//

	#ifndef _LIBCPP___TUPLE
	#define _LIBCPP___TUPLE

	#include <__config>
	#include <cstddef>
	#include <type_traits>

	#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
	#pragma GCC system_header
	#endif

	#ifdef _LIBCPP_HAS_NO_VARIADICS

	#include <__tuple_03>

	#else // _LIBCPP_HAS_NO_VARIADICS

	_LIBCPP_BEGIN_NAMESPACE_STD

	template <class _Tp> class _LIBCPP_TYPE_VIS tuple_size;

	template <class _Tp>
	class _LIBCPP_TYPE_VIS tuple_size<const _Tp>
	: public tuple_size<_Tp> {};

	template <class _Tp>
	class _LIBCPP_TYPE_VIS tuple_size<volatile _Tp>
	: public tuple_size<_Tp> {};

	template <class _Tp>
	class _LIBCPP_TYPE_VIS tuple_size<const volatile _Tp>
	: public tuple_size<_Tp> {};

	template <size_t _Ip, class _Tp> class _LIBCPP_TYPE_VIS tuple_element;

	template <size_t _Ip, class _Tp>
	class _LIBCPP_TYPE_VIS tuple_element<_Ip, const _Tp>
	{
	public:
	typedef typename add_const<typename tuple_element<_Ip, _Tp>::type>::type type;
	};

	template <size_t _Ip, class _Tp>
	class _LIBCPP_TYPE_VIS tuple_element<_Ip, volatile _Tp>
	{
	public:
	typedef typename add_volatile<typename tuple_element<_Ip, _Tp>::type>::type type;
	};

	template <size_t _Ip, class _Tp>
	class _LIBCPP_TYPE_VIS tuple_element<_Ip, const volatile _Tp>
	{
	public:
	typedef typename add_cv<typename tuple_element<_Ip, _Tp>::type>::type type;
	};

	template <class ..._Tp> class _LIBCPP_TYPE_VIS tuple;
	template <class _T1, class _T2> struct _LIBCPP_TYPE_VIS pair;
	template <class _Tp, size_t _Size> struct _LIBCPP_TYPE_VIS array;

	template <class _Tp> struct __tuple_like : false_type {};

	template <class _Tp> struct __tuple_like<const _Tp> : public __tuple_like<_Tp> {};
	template <class _Tp> struct __tuple_like<volatile _Tp> : public __tuple_like<_Tp> {};
	template <class _Tp> struct __tuple_like<const volatile _Tp> : public __tuple_like<_Tp> {};

	template <class... _Tp> struct __tuple_like<tuple<_Tp...> > : true_type {};
	template <class _T1, class _T2> struct __tuple_like<pair<_T1, _T2> > : true_type {};
	template <class _Tp, size_t _Size> struct __tuple_like<array<_Tp, _Size> > : true_type {};

	template <size_t _Ip, class ..._Tp>
	_LIBCPP_INLINE_VISIBILITY
	typename tuple_element<_Ip, tuple<_Tp...> >::type&
	get(tuple<_Tp...>&) _NOEXCEPT;

	template <size_t _Ip, class ..._Tp>
	_LIBCPP_INLINE_VISIBILITY
	const typename tuple_element<_Ip, tuple<_Tp...> >::type&
	get(const tuple<_Tp...>&) _NOEXCEPT;

	template <size_t _Ip, class ..._Tp>
	_LIBCPP_INLINE_VISIBILITY
	typename tuple_element<_Ip, tuple<_Tp...> >::type&&
	get(tuple<_Tp...>&&) _NOEXCEPT;

	template <size_t _Ip, class _T1, class _T2>
	_LIBCPP_INLINE_VISIBILITY
	typename tuple_element<_Ip, pair<_T1, _T2> >::type&
	get(pair<_T1, _T2>&) _NOEXCEPT;

	template <size_t _Ip, class _T1, class _T2>
	_LIBCPP_INLINE_VISIBILITY
	const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
	get(const pair<_T1, _T2>&) _NOEXCEPT;

	template <size_t _Ip, class _T1, class _T2>
	_LIBCPP_INLINE_VISIBILITY
	typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
	get(pair<_T1, _T2>&&) _NOEXCEPT;

	template <size_t _Ip, class _Tp, size_t _Size>
	_LIBCPP_INLINE_VISIBILITY
	_Tp&
	get(array<_Tp, _Size>&) _NOEXCEPT;

	template <size_t _Ip, class _Tp, size_t _Size>
	_LIBCPP_INLINE_VISIBILITY
	const _Tp&
	get(const array<_Tp, _Size>&) _NOEXCEPT;

	template <size_t _Ip, class _Tp, size_t _Size>
	_LIBCPP_INLINE_VISIBILITY
	_Tp&&
	get(array<_Tp, _Size>&&) _NOEXCEPT;

	// __make_tuple_indices

	template <size_t...> struct __tuple_indices {};

	template <size_t _Sp, class _IntTuple, size_t _Ep>
	struct __make_indices_imp;

	template <size_t _Sp, size_t ..._Indices, size_t _Ep>
	struct __make_indices_imp<_Sp, __tuple_indices<_Indices...>, _Ep>
	{
	typedef typename __make_indices_imp<_Sp+1, __tuple_indices<_Indices..., _Sp>, _Ep>::type type;
	};

	template <size_t _Ep, size_t ..._Indices>
	struct __make_indices_imp<_Ep, __tuple_indices<_Indices...>, _Ep>
	{
	typedef __tuple_indices<_Indices...> type;
	};

	template <size_t _Ep, size_t _Sp = 0>
	struct __make_tuple_indices
	{
	static_assert(_Sp <= _Ep, "__make_tuple_indices input error");
	typedef typename __make_indices_imp<_Sp, __tuple_indices<>, _Ep>::type type;
	};

	// __tuple_types

	template <class ..._Tp> struct __tuple_types {};

	template <size_t _Ip>
	class _LIBCPP_TYPE_VIS tuple_element<_Ip, __tuple_types<> >
	{
	public:
	static_assert(_Ip == 0, "tuple_element index out of range");
	static_assert(_Ip != 0, "tuple_element index out of range");
	};

	template <class _Hp, class ..._Tp>
	class _LIBCPP_TYPE_VIS tuple_element<0, __tuple_types<_Hp, _Tp...> >
	{
	public:
	typedef _Hp type;
	};

	template <size_t _Ip, class _Hp, class ..._Tp>
	class _LIBCPP_TYPE_VIS tuple_element<_Ip, __tuple_types<_Hp, _Tp...> >
	{
	public:
	typedef typename tuple_element<_Ip-1, __tuple_types<_Tp...> >::type type;
	};

	template <class ..._Tp>
	class _LIBCPP_TYPE_VIS tuple_size<__tuple_types<_Tp...> >
	: public integral_constant<size_t, sizeof...(_Tp)>
	{
	};

	template <class... _Tp> struct __tuple_like<__tuple_types<_Tp...> > : true_type {};

	// __make_tuple_types

	// __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
	// __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
	// _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>. If _Tuple is a
	// lvalue_reference type, then __tuple_types<_Types&...> is the result.

	template <class _TupleTypes, class _Tp, size_t _Sp, size_t _Ep>
	struct __make_tuple_types_imp;

	template <class ..._Types, class _Tp, size_t _Sp, size_t _Ep>
	struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Sp, _Ep>
	{
	typedef typename remove_reference<_Tp>::type _Tpr;
	typedef typename __make_tuple_types_imp<__tuple_types<_Types...,
	typename conditional<is_lvalue_reference<_Tp>::value,
	typename tuple_element<_Sp, _Tpr>::type&,
	typename tuple_element<_Sp, _Tpr>::type>::type>,
	_Tp, _Sp+1, _Ep>::type type;
	};

	template <class ..._Types, class _Tp, size_t _Ep>
	struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Ep, _Ep>
	{
	typedef __tuple_types<_Types...> type;
	};

	template <class _Tp, size_t _Ep = tuple_size<typename remove_reference<_Tp>::type>::value, size_t _Sp = 0>
	struct __make_tuple_types
	{
	static_assert(_Sp <= _Ep, "__make_tuple_types input error");
	typedef typename __make_tuple_types_imp<__tuple_types<>, _Tp, _Sp, _Ep>::type type;
	};

	// __tuple_convertible

	template <bool, class _Tp, class _Up>
	struct __tuple_convertible_imp : public false_type {};

	template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
	struct __tuple_convertible_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
	: public integral_constant<bool,
	is_convertible<_Tp0, _Up0>::value &&
	__tuple_convertible_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

	template <>
	struct __tuple_convertible_imp<true, __tuple_types<>, __tuple_types<> >
	: public true_type {};

	template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
	bool = __tuple_like<_Up>::value>
	struct __tuple_convertible
	: public false_type {};

	template <class _Tp, class _Up>
	struct __tuple_convertible<_Tp, _Up, true, true>
	: public __tuple_convertible_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
	tuple_size<_Up>::value,
	typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
	{};

	// __tuple_constructible

	template <bool, class _Tp, class _Up>
	struct __tuple_constructible_imp : public false_type {};

	template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
	struct __tuple_constructible_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
	: public integral_constant<bool,
	is_constructible<_Up0, _Tp0>::value &&
	__tuple_constructible_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

	template <>
	struct __tuple_constructible_imp<true, __tuple_types<>, __tuple_types<> >
	: public true_type {};

	template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
	bool = __tuple_like<_Up>::value>
	struct __tuple_constructible
	: public false_type {};

	template <class _Tp, class _Up>
	struct __tuple_constructible<_Tp, _Up, true, true>
	: public __tuple_constructible_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
	tuple_size<_Up>::value,
	typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
	{};

	// __tuple_assignable

	template <bool, class _Tp, class _Up>
	struct __tuple_assignable_imp : public false_type {};

	template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
	struct __tuple_assignable_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
	: public integral_constant<bool,
	is_assignable<_Up0&, _Tp0>::value &&
	__tuple_assignable_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};

	template <>
	struct __tuple_assignable_imp<true, __tuple_types<>, __tuple_types<> >
	: public true_type {};

	template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
	bool = __tuple_like<_Up>::value>
	struct __tuple_assignable
	: public false_type {};

	template <class _Tp, class _Up>
	struct __tuple_assignable<_Tp, _Up, true, true>
	: public __tuple_assignable_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
	tuple_size<_Up>::value,
	typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
	{};

	_LIBCPP_END_NAMESPACE_STD

	#endif // _LIBCPP_HAS_NO_VARIADICS

	#endif // _LIBCPP___TUPLE