path: root/contrib/libs/cxxsupp/libcxx/include/__tuple

// -*- C++ -*- 
//===----------------------------------------------------------------------===// 
// 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// 
//===----------------------------------------------------------------------===// 
 
#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 
 
 
_LIBCPP_BEGIN_NAMESPACE_STD 
 
template <class _Tp> class _LIBCPP_TEMPLATE_VIS tuple_size; 
 
#if !defined(_LIBCPP_CXX03_LANG) 
template <class _Tp, class...> 
using __enable_if_tuple_size_imp = _Tp; 
 
template <class _Tp> 
class _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< 
    const _Tp, 
    typename enable_if<!is_volatile<_Tp>::value>::type, 
    integral_constant<size_t, sizeof(tuple_size<_Tp>)>>> 
    : public integral_constant<size_t, tuple_size<_Tp>::value> {}; 
 
template <class _Tp> 
class _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< 
    volatile _Tp, 
    typename enable_if<!is_const<_Tp>::value>::type, 
    integral_constant<size_t, sizeof(tuple_size<_Tp>)>>> 
    : public integral_constant<size_t, tuple_size<_Tp>::value> {}; 
 
template <class _Tp> 
class _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< 
    const volatile _Tp, 
    integral_constant<size_t, sizeof(tuple_size<_Tp>)>>> 
    : public integral_constant<size_t, tuple_size<_Tp>::value> {}; 
 
#else 
template <class _Tp> class _LIBCPP_TEMPLATE_VIS tuple_size<const _Tp> : public tuple_size<_Tp> {}; 
template <class _Tp> class _LIBCPP_TEMPLATE_VIS tuple_size<volatile _Tp> : public tuple_size<_Tp> {}; 
template <class _Tp> class _LIBCPP_TEMPLATE_VIS tuple_size<const volatile _Tp> : public tuple_size<_Tp> {}; 
#endif 
 
template <size_t _Ip, class _Tp> struct _LIBCPP_TEMPLATE_VIS tuple_element; 
 
template <size_t _Ip, class _Tp> 
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const _Tp> 
{ 
    typedef _LIBCPP_NODEBUG typename add_const<typename tuple_element<_Ip, _Tp>::type>::type type; 
}; 
 
template <size_t _Ip, class _Tp> 
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, volatile _Tp> 
{ 
    typedef _LIBCPP_NODEBUG typename add_volatile<typename tuple_element<_Ip, _Tp>::type>::type type; 
}; 
 
template <size_t _Ip, class _Tp> 
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const volatile _Tp> 
{ 
    typedef _LIBCPP_NODEBUG typename add_cv<typename tuple_element<_Ip, _Tp>::type>::type type; 
}; 
 
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> {}; 
 
// tuple specializations 
 
#ifndef _LIBCPP_CXX03_LANG 
 
template <size_t...> struct __tuple_indices {}; 
 
template <class _IdxType, _IdxType... _Values> 
struct __integer_sequence { 
  template <size_t _Sp> 
  using __to_tuple_indices = __tuple_indices<(_Values + _Sp)...>; 
}; 
 
#if defined(__CUDACC__) || !__has_builtin(__make_integer_seq) || defined(_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
namespace __detail { 
 
template<typename _Tp, size_t ..._Extra> struct __repeat; 
template<typename _Tp, _Tp ..._Np, size_t ..._Extra> struct __repeat<__integer_sequence<_Tp, _Np...>, _Extra...> { 
  typedef _LIBCPP_NODEBUG __integer_sequence<_Tp, 
                           _Np..., 
                           sizeof...(_Np) + _Np..., 
                           2 * sizeof...(_Np) + _Np..., 
                           3 * sizeof...(_Np) + _Np..., 
                           4 * sizeof...(_Np) + _Np..., 
                           5 * sizeof...(_Np) + _Np..., 
                           6 * sizeof...(_Np) + _Np..., 
                           7 * sizeof...(_Np) + _Np..., 
                           _Extra...> type; 
}; 
 
template<size_t _Np> struct __parity; 
template<size_t _Np> struct __make : __parity<_Np % 8>::template __pmake<_Np> {}; 
 
template<> struct __make<0> { typedef __integer_sequence<size_t> type; }; 
template<> struct __make<1> { typedef __integer_sequence<size_t, 0> type; }; 
template<> struct __make<2> { typedef __integer_sequence<size_t, 0, 1> type; }; 
template<> struct __make<3> { typedef __integer_sequence<size_t, 0, 1, 2> type; }; 
template<> struct __make<4> { typedef __integer_sequence<size_t, 0, 1, 2, 3> type; }; 
template<> struct __make<5> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4> type; }; 
template<> struct __make<6> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4, 5> type; }; 
template<> struct __make<7> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4, 5, 6> type; }; 
 
template<> struct __parity<0> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type> {}; }; 
template<> struct __parity<1> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 1> {}; }; 
template<> struct __parity<2> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 2, _Np - 1> {}; }; 
template<> struct __parity<3> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 3, _Np - 2, _Np - 1> {}; }; 
template<> struct __parity<4> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; }; 
template<> struct __parity<5> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; }; 
template<> struct __parity<6> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; }; 
template<> struct __parity<7> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 7, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; }; 
 
} // namespace detail 
 
#endif // !__has_builtin(__make_integer_seq) || defined(_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE) 
 
#if __has_builtin(__make_integer_seq) && !defined(__CUDACC__)
template <size_t _Ep, size_t _Sp> 
using __make_indices_imp = 
    typename __make_integer_seq<__integer_sequence, size_t, _Ep - _Sp>::template 
    __to_tuple_indices<_Sp>; 
#else 
template <size_t _Ep, size_t _Sp> 
using __make_indices_imp = 
    typename __detail::__make<_Ep - _Sp>::type::template __to_tuple_indices<_Sp>; 
 
#endif 
 
template <size_t _Ep, size_t _Sp = 0> 
struct __make_tuple_indices 
{ 
    static_assert(_Sp <= _Ep, "__make_tuple_indices input error"); 
    typedef __make_indices_imp<_Ep, _Sp> type; 
}; 
 
 
template <class ..._Tp> class _LIBCPP_TEMPLATE_VIS tuple; 
 
template <class... _Tp> struct __tuple_like<tuple<_Tp...> > : true_type {}; 
 
template <class ..._Tp> 
class _LIBCPP_TEMPLATE_VIS tuple_size<tuple<_Tp...> > 
    : public integral_constant<size_t, sizeof...(_Tp)> 
{ 
}; 
 
template <size_t _Ip, class ..._Tp> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
typename tuple_element<_Ip, tuple<_Tp...> >::type& 
get(tuple<_Tp...>&) _NOEXCEPT; 
 
template <size_t _Ip, class ..._Tp> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const typename tuple_element<_Ip, tuple<_Tp...> >::type& 
get(const tuple<_Tp...>&) _NOEXCEPT; 
 
template <size_t _Ip, class ..._Tp> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
typename tuple_element<_Ip, tuple<_Tp...> >::type&& 
get(tuple<_Tp...>&&) _NOEXCEPT; 
 
template <size_t _Ip, class ..._Tp> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const typename tuple_element<_Ip, tuple<_Tp...> >::type&& 
get(const tuple<_Tp...>&&) _NOEXCEPT; 
 
#endif // !defined(_LIBCPP_CXX03_LANG) 
 
// pair specializations 
 
template <class _T1, class _T2> struct __tuple_like<pair<_T1, _T2> > : true_type {}; 
 
template <size_t _Ip, class _T1, class _T2> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
typename tuple_element<_Ip, pair<_T1, _T2> >::type& 
get(pair<_T1, _T2>&) _NOEXCEPT; 
 
template <size_t _Ip, class _T1, class _T2> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const typename tuple_element<_Ip, pair<_T1, _T2> >::type& 
get(const pair<_T1, _T2>&) _NOEXCEPT; 
 
#ifndef _LIBCPP_CXX03_LANG 
template <size_t _Ip, class _T1, class _T2> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
typename tuple_element<_Ip, pair<_T1, _T2> >::type&& 
get(pair<_T1, _T2>&&) _NOEXCEPT; 
 
template <size_t _Ip, class _T1, class _T2> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const typename tuple_element<_Ip, pair<_T1, _T2> >::type&& 
get(const pair<_T1, _T2>&&) _NOEXCEPT; 
#endif 
 
// array specializations 
 
template <class _Tp, size_t _Size> struct _LIBCPP_TEMPLATE_VIS array; 
 
template <class _Tp, size_t _Size> struct __tuple_like<array<_Tp, _Size> > : true_type {}; 
 
template <size_t _Ip, class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
_Tp& 
get(array<_Tp, _Size>&) _NOEXCEPT; 
 
template <size_t _Ip, class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const _Tp& 
get(const array<_Tp, _Size>&) _NOEXCEPT; 
 
#ifndef _LIBCPP_CXX03_LANG 
template <size_t _Ip, class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
_Tp&& 
get(array<_Tp, _Size>&&) _NOEXCEPT; 
 
template <size_t _Ip, class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 
const _Tp&& 
get(const array<_Tp, _Size>&&) _NOEXCEPT; 
#endif 
 
#ifndef _LIBCPP_CXX03_LANG 
 
// __tuple_types 
 
template <class ..._Tp> struct __tuple_types {}; 
 
#if !__has_builtin(__type_pack_element) 
 
namespace __indexer_detail { 
 
template <size_t _Idx, class _Tp> 
struct __indexed { using type _LIBCPP_NODEBUG = _Tp; }; 
 
template <class _Types, class _Indexes> struct __indexer; 
 
template <class ..._Types, size_t ..._Idx> 
struct __indexer<__tuple_types<_Types...>, __tuple_indices<_Idx...>> 
    : __indexed<_Idx, _Types>... 
{}; 
 
template <size_t _Idx, class _Tp> 
__indexed<_Idx, _Tp> __at_index(__indexed<_Idx, _Tp> const&); 
 
} // namespace __indexer_detail 
 
#if !defined(__CUDACC__) || !defined(_MSC_VER)
template <size_t _Idx, class ..._Types> 
using __type_pack_element _LIBCPP_NODEBUG = typename decltype( 
    __indexer_detail::__at_index<_Idx>( 
        __indexer_detail::__indexer< 
            __tuple_types<_Types...>, 
            typename __make_tuple_indices<sizeof...(_Types)>::type 
        >{}) 
  )::type; 
 
#else // !defined(__CUDACC__) || !defined(_MSC_VER)
template <size_t _Idx, class ..._Types>
struct __y_type_pack_element {
    using __t1 = typename __make_tuple_indices<sizeof...(_Types)>::type;
    using __t2 = __indexer_detail::__indexer<__tuple_types<_Types...>, __t1>;
    using __t3 = decltype(__indexer_detail::__at_index<_Idx>(__t2{}));
    using __t4 = typename __t3::type;
};

template <size_t _Idx, class ..._Types>
using __type_pack_element = typename __y_type_pack_element<_Idx, _Types...>::__t4;

#endif // !defined(__CUDACC__) || !defined(_MSC_VER)

#endif // __has_builtin(__type_pack_element) 
 
template <size_t _Ip, class ..._Types> 
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, __tuple_types<_Types...>> 
{ 
    static_assert(_Ip < sizeof...(_Types), "tuple_element index out of range"); 
    typedef _LIBCPP_NODEBUG __type_pack_element<_Ip, _Types...> type; 
}; 
 
 
template <class ..._Tp> 
class _LIBCPP_TEMPLATE_VIS tuple_size<__tuple_types<_Tp...> > 
    : public integral_constant<size_t, sizeof...(_Tp)> 
{ 
}; 
 
template <class... _Tp> struct __tuple_like<__tuple_types<_Tp...> > : true_type {}; 
 
template <bool _ApplyLV, bool _ApplyConst, bool _ApplyVolatile> 
struct __apply_cv_mf; 
template <> 
struct __apply_cv_mf<false, false, false> { 
  template <class _Tp> using __apply = _Tp; 
}; 
template <> 
struct __apply_cv_mf<false, true, false> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = const _Tp; 
}; 
template <> 
struct __apply_cv_mf<false, false, true> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = volatile _Tp; 
}; 
template <> 
struct __apply_cv_mf<false, true, true> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = const volatile _Tp; 
}; 
template <> 
struct __apply_cv_mf<true, false, false> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = _Tp&; 
}; 
template <> 
struct __apply_cv_mf<true, true, false> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = const _Tp&; 
}; 
template <> 
struct __apply_cv_mf<true, false, true> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = volatile _Tp&; 
}; 
template <> 
struct __apply_cv_mf<true, true, true> { 
  template <class _Tp> using __apply _LIBCPP_NODEBUG = const volatile _Tp&; 
}; 
template <class _Tp, class _RawTp = typename remove_reference<_Tp>::type> 
using __apply_cv_t _LIBCPP_NODEBUG = __apply_cv_mf< 
    is_lvalue_reference<_Tp>::value, 
    is_const<_RawTp>::value, 
    is_volatile<_RawTp>::value>; 
 
// __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. 
 
#ifdef _LIBCPP_COMPILER_MSVC 
 
template<class _TupleTypes, class _Tp> 
struct __make_tuple_types_append_front; 
 
template<class ..._Types, class _Tp> 
struct __make_tuple_types_append_front<__tuple_types<_Types...>, _Tp> { 
    using type = __tuple_types<_Tp, _Types...>; 
}; 
 
template<class _TupleTypes, class _Apply, size_t _Ep, size_t _Sp, class = void> 
struct __make_tuple_types_flat; 
 
template<class _Tuple, class _Apply> 
struct __make_tuple_types_flat<_Tuple, _Apply, 0, 0, void> { 
    using type = __tuple_types<>; 
}; 
 
template<template<class...> class _Tuple, class _Tp, class ..._Types, class _Apply, size_t _Ep> 
struct __make_tuple_types_flat<_Tuple<_Tp, _Types...>, _Apply, _Ep, 0, enable_if_t<(_Ep > 0)>> { 
    using type = typename __make_tuple_types_append_front< 
        typename __make_tuple_types_flat<__tuple_types<_Types...>, _Apply, _Ep - 1, 0>::type, 
        typename _Apply::template __apply<_Tp>>::type; 
}; 
 
template<template <class...> class _Tuple, class _Tp, class ..._Types, class _Apply, size_t _Ep, size_t _Sp> 
struct __make_tuple_types_flat<_Tuple<_Tp, _Types...>, _Apply, _Ep, _Sp, enable_if_t<(_Ep > 0 && _Sp > 0)>> { 
    using type = typename __make_tuple_types_flat<__tuple_types<_Types...>, _Apply, _Ep - 1, _Sp - 1>::type; 
}; 
 
template<class _Tp, size_t _Np, class _Apply, size_t _Ep> 
struct __make_tuple_types_flat<array<_Tp, _Np>, _Apply, _Ep, 0, enable_if_t<(_Ep > 0)>> { 
    using type = typename __make_tuple_types_append_front< 
        typename __make_tuple_types_flat<array<_Tp, _Np>, _Apply, _Ep - 1, 0>::type, 
        typename _Apply::template __apply<_Tp>>::type;
}; 
 
template<class _Tp, size_t _Np, class _Apply, size_t _Ep, size_t _Sp> 
struct __make_tuple_types_flat<array<_Tp, _Np>, _Apply, _Ep, _Sp, enable_if_t<(_Sp > 0)>> { 
    using type = typename __make_tuple_types_flat<array<_Tp, _Np>, _Apply, _Ep - _Sp, 0>::type; 
}; 
 
template<class _Tp, 
         size_t _Ep = tuple_size<remove_reference_t<_Tp>>::value, 
         size_t _Sp = 0, 
         bool _SameSize = (_Ep == tuple_size<typename remove_reference<_Tp>::type>::value)> 
struct __make_tuple_types { 
    static_assert(_Sp <= _Ep, "__make_tuple_types input error"); 
    using _RawTp = typename remove_cv<typename remove_reference<_Tp>::type>::type; 
    using type = typename __make_tuple_types_flat<_RawTp, __apply_cv_t<_Tp>, _Ep, _Sp>::type; 
}; 
 
template <class ..._Types, size_t _Ep> 
struct __make_tuple_types<tuple<_Types...>, _Ep, 0, true> { 
  typedef __tuple_types<_Types...> type; 
}; 
 
template <class ..._Types, size_t _Ep> 
struct __make_tuple_types<__tuple_types<_Types...>, _Ep, 0, true> { 
  typedef __tuple_types<_Types...> type; 
}; 
 
#else 
 
template <class _TupleTypes, class _TupleIndices> 
struct __make_tuple_types_flat; 
 
template <template <class...> class _Tuple, class ..._Types, size_t ..._Idx> 
struct __make_tuple_types_flat<_Tuple<_Types...>, __tuple_indices<_Idx...>> { 
  // Specialization for pair, tuple, and __tuple_types 
  template <class _Tp, class _ApplyFn = __apply_cv_t<_Tp>> 
  using __apply_quals _LIBCPP_NODEBUG = __tuple_types< 
      typename _ApplyFn::template __apply<__type_pack_element<_Idx, _Types...>>... 
    >; 
}; 
 
template <class _Vt, size_t _Np, size_t ..._Idx> 
struct __make_tuple_types_flat<array<_Vt, _Np>, __tuple_indices<_Idx...>> { 
  template <size_t> 
  using __value_type = _Vt; 
  template <class _Tp, class _ApplyFn = __apply_cv_t<_Tp>> 
  using __apply_quals = __tuple_types< 
      typename _ApplyFn::template __apply<__value_type<_Idx>>... 
    >; 
}; 
 
template <class _Tp, size_t _Ep = tuple_size<typename remove_reference<_Tp>::type>::value, 
          size_t _Sp = 0, 
          bool _SameSize = (_Ep == tuple_size<typename remove_reference<_Tp>::type>::value)> 
struct __make_tuple_types 
{ 
    static_assert(_Sp <= _Ep, "__make_tuple_types input error"); 
    using _RawTp = typename remove_cv<typename remove_reference<_Tp>::type>::type; 
    using _Maker = __make_tuple_types_flat<_RawTp, typename __make_tuple_indices<_Ep, _Sp>::type>; 
    using type = typename _Maker::template __apply_quals<_Tp>; 
}; 
 
template <class ..._Types, size_t _Ep> 
struct __make_tuple_types<tuple<_Types...>, _Ep, 0, true> { 
  typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type; 
}; 
 
template <class ..._Types, size_t _Ep> 
struct __make_tuple_types<__tuple_types<_Types...>, _Ep, 0, true> { 
  typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type; 
}; 
 
#endif // _LIBCPP_COMPILER_MSVC 
 
template <bool ..._Preds> 
struct __all_dummy; 
 
template <bool ..._Pred> 
using __all = _IsSame<__all_dummy<_Pred...>, __all_dummy<(_Pred | true)...>>; 
 
struct __tuple_sfinae_base { 
  template <template <class, class...> class _Trait, 
            class ..._LArgs, class ..._RArgs> 
  static auto __do_test(__tuple_types<_LArgs...>, __tuple_types<_RArgs...>) 
    -> __all<_Trait<_LArgs, _RArgs>::value...>; 
  template <template <class...> class> 
  static auto __do_test(...) -> false_type; 
 
  template <class _FromArgs, class _ToArgs> 
  using __constructible = decltype(__do_test<is_constructible>(declval<_ToArgs>(), declval<_FromArgs>())); 
  template <class _FromArgs, class _ToArgs> 
  using __convertible = decltype(__do_test<is_convertible>(declval<_FromArgs>(), declval<_ToArgs>())); 
  template <class _FromArgs, class _ToArgs> 
  using __assignable = decltype(__do_test<is_assignable>(declval<_ToArgs>(), declval<_FromArgs>())); 
}; 
 
// __tuple_convertible 
 
template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value, 
                                bool = __tuple_like<_Up>::value, 
                                class = void> 
struct __tuple_convertible 
    : public false_type {}; 
 
template <class _Tp, class _Up> 
struct __tuple_convertible<_Tp, _Up, true, true, 
                           typename enable_if<(tuple_size<typename remove_reference<_Tp>::type>::value == tuple_size<_Up>::value)>::type> 
    : public __tuple_sfinae_base::__convertible< 
      typename __make_tuple_types<_Tp>::type 
    , typename __make_tuple_types<_Up>::type 
    > 
{}; 
 
// __tuple_constructible 
 
template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value, 
                                bool = __tuple_like<_Up>::value, 
                                class = void> 
struct __tuple_constructible 
    : public false_type {}; 
 
template <class _Tp, class _Up> 
struct __tuple_constructible<_Tp, _Up, true, true, 
                             typename enable_if<(tuple_size<typename remove_reference<_Tp>::type>::value == tuple_size<_Up>::value)>::type> 
    : public __tuple_sfinae_base::__constructible< 
      typename __make_tuple_types<_Tp>::type 
    , typename __make_tuple_types<_Up>::type 
    > 
{}; 
 
// __tuple_assignable 
 
template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value, 
                                bool = __tuple_like<_Up>::value, 
                                class = void> 
struct __tuple_assignable 
    : public false_type {}; 
 
template <class _Tp, class _Up> 
struct __tuple_assignable<_Tp, _Up, true, true, 
                          typename enable_if<(tuple_size<typename remove_reference<_Tp>::type>::value == tuple_size<_Up>::value)>::type> 
    : public __tuple_sfinae_base::__assignable< 
      typename __make_tuple_types<_Tp>::type 
    , typename __make_tuple_types<_Up&>::type 
    > 
{}; 
 
 
template <size_t _Ip, class ..._Tp> 
struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, tuple<_Tp...> > 
{ 
    typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, __tuple_types<_Tp...> >::type type; 
}; 
 
#if _LIBCPP_STD_VER > 11 
template <size_t _Ip, class ..._Tp> 
using tuple_element_t _LIBCPP_NODEBUG = typename tuple_element <_Ip, _Tp...>::type; 
#endif 
 
template <bool _IsTuple, class _SizeTrait, size_t _Expected> 
struct __tuple_like_with_size_imp : false_type {}; 
 
template <class _SizeTrait, size_t _Expected> 
struct __tuple_like_with_size_imp<true, _SizeTrait, _Expected> 
    : integral_constant<bool, _SizeTrait::value == _Expected> {}; 
 
template <class _Tuple, size_t _ExpectedSize, 
          class _RawTuple = typename __uncvref<_Tuple>::type> 
using __tuple_like_with_size _LIBCPP_NODEBUG = __tuple_like_with_size_imp< 
                                   __tuple_like<_RawTuple>::value, 
                                   tuple_size<_RawTuple>, _ExpectedSize 
                              >; 
 
struct _LIBCPP_TYPE_VIS __check_tuple_constructor_fail { 
 
    static constexpr bool __enable_explicit_default() { return false; } 
    static constexpr bool __enable_implicit_default() { return false; } 
    template <class ...> 
    static constexpr bool __enable_explicit() { return false; } 
    template <class ...> 
    static constexpr bool __enable_implicit() { return false; } 
    template <class ...> 
    static constexpr bool __enable_assign() { return false; } 
}; 
#endif // !defined(_LIBCPP_CXX03_LANG) 
 
#if _LIBCPP_STD_VER > 14 
 
template <bool _CanCopy, bool _CanMove> 
struct __sfinae_ctor_base {}; 
template <> 
struct __sfinae_ctor_base<false, false> { 
  __sfinae_ctor_base() = default; 
  __sfinae_ctor_base(__sfinae_ctor_base const&) = delete; 
  __sfinae_ctor_base(__sfinae_ctor_base &&) = delete; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; 
}; 
template <> 
struct __sfinae_ctor_base<true, false> { 
  __sfinae_ctor_base() = default; 
  __sfinae_ctor_base(__sfinae_ctor_base const&) = default; 
  __sfinae_ctor_base(__sfinae_ctor_base &&) = delete; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; 
}; 
template <> 
struct __sfinae_ctor_base<false, true> { 
  __sfinae_ctor_base() = default; 
  __sfinae_ctor_base(__sfinae_ctor_base const&) = delete; 
  __sfinae_ctor_base(__sfinae_ctor_base &&) = default; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; 
  __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; 
}; 
 
template <bool _CanCopy, bool _CanMove> 
struct __sfinae_assign_base {}; 
template <> 
struct __sfinae_assign_base<false, false> { 
  __sfinae_assign_base() = default; 
  __sfinae_assign_base(__sfinae_assign_base const&) = default; 
  __sfinae_assign_base(__sfinae_assign_base &&) = default; 
  __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete; 
  __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete; 
}; 
template <> 
struct __sfinae_assign_base<true, false> { 
  __sfinae_assign_base() = default; 
  __sfinae_assign_base(__sfinae_assign_base const&) = default; 
  __sfinae_assign_base(__sfinae_assign_base &&) = default; 
  __sfinae_assign_base& operator=(__sfinae_assign_base const&) = default; 
  __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete; 
}; 
template <> 
struct __sfinae_assign_base<false, true> { 
  __sfinae_assign_base() = default; 
  __sfinae_assign_base(__sfinae_assign_base const&) = default; 
  __sfinae_assign_base(__sfinae_assign_base &&) = default; 
  __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete; 
  __sfinae_assign_base& operator=(__sfinae_assign_base&&) = default; 
}; 
#endif // _LIBCPP_STD_VER > 14 
 
_LIBCPP_END_NAMESPACE_STD 
 
#endif // _LIBCPP___TUPLE