Standard library header <tuple> (C++11)

#include <compare>
namespace std {
  // class template tuple
  template<class... 类型>
    class tuple;
  // tuple creation functions
  inline constexpr /* 未指定 */ ignore;
  template<class... TTypes>
    constexpr tuple<unwrap_ref_decay_t<TTypes>...> make_tuple(TTypes&&...);
  template<class... TTypes>
    constexpr tuple<TTypes&&...> forward_as_tuple(TTypes&&...) noexcept;
  template<class... TTypes>
    constexpr tuple<TTypes&...> tie(TTypes&...) noexcept;
  template<class... Tuples>
    constexpr tuple<CTypes...> tuple_cat(Tuples&&...);
  // 使用参数元组调用函数
  template<class F, class Tuple>
    constexpr decltype(auto) apply(F&& f, Tuple&& t);
  template<class T, class Tuple>
    constexpr T make_from_tuple(Tuple&& t);
  // tuple helper classes
  template<class T> struct tuple_size;                  // 未定义
  template<class T> struct tuple_size<const T>;
  template<class... Types> struct tuple_size<tuple<Types...>>;
  template<size_t I, class T> struct tuple_element;     // 未定义
  template<size_t I, class T> struct tuple_element<I, const T>;
  template<size_t I, class... Types>
    struct tuple_element<I, tuple<Types...>>;
  template<size_t I, class T>
    using tuple_element_t = typename tuple_element<I, T>::type;
  // 元素访问
  template<size_t I, class... Types>
    constexpr tuple_element_t<I, tuple<Types...>>& get(tuple<Types...>&) noexcept;
  template<size_t I, class... Types>
    constexpr tuple_element_t<I, tuple<Types...>>&& get(tuple<Types...>&&) noexcept;
  template<size_t I, class... Types>
    constexpr const tuple_element_t<I, tuple<Types...>>&
      get(const tuple<Types...>&) noexcept;
  template<size_t I, class... 类型>
    constexpr const tuple_element_t<I, tuple<Types...>>&&
      get(const tuple<Types...>&&) noexcept;
  template<class T, class... Types>
    constexpr T& get(tuple<Types...>& t) noexcept;
  template<class T, class... 类型>
    constexpr T&& get(tuple<Types...>&& t) noexcept;
  template<class T, class... Types>
    constexpr const T& get(const tuple<Types...>& t) noexcept;
  template<class T, class... Types>
    constexpr const T&& get(const tuple<Types...>&& t) noexcept;
  // 关系运算符
  template<class... TTypes, class... UTypes>
    constexpr bool operator==(const tuple<TTypes...>&, const tuple<UTypes...>&);
  template<class... TTypes, class... UTypes>
    constexpr common_comparison_category_t</*synth-three-way-result*/<TTypes, UTypes>...>
      operator<=>(const tuple<TTypes...>&, const tuple<UTypes...>&);
  // 分配器相关特性
  template<class... Types, class Alloc>
    struct uses_allocator<tuple<Types...>, Alloc>;
  // specialized algorithms
  template<class... Types>
    constexpr void
      swap(tuple<Types...>& x, tuple<Types...>& y) noexcept(/* 查看描述 */);
  // tuple helper classes
  template<class T>
    inline constexpr size_t tuple_size_v = tuple_size<T>::值;
}
// deprecated
namespace std {
  template<class T> class tuple_size<volatile T>;
  template<class T> class tuple_size<const volatile T>;
  template<size_t I, class T> class tuple_element<I, volatile T>;
  template<size_t I, class T> class tuple_element<I, const volatile T>;
}

namespace std {
  template<class... Types>
  class tuple {
  public:
    // tuple construction
    constexpr explicit(/* 查看描述 */) tuple();
    constexpr explicit(/* 查看描述 */)
      tuple(const Types&...);         // 仅当 sizeof...(Types) >= 1
    template<class... UTypes>
      constexpr explicit(/* 查看描述 */)
        tuple(UTypes&&...);           // 仅当 sizeof...(Types) >= 1
    tuple(const tuple&) = default;
    tuple(tuple&&) = default;
    template<class... UTypes>
      constexpr explicit(/* 查看描述 */) tuple(const tuple<UTypes...>&);
    template<class... UTypes>
      constexpr explicit(/* 查看描述 */) tuple(tuple<UTypes...>&&);
    template<class U1, class U2>
      constexpr explicit(/* 查看描述 */)
        tuple(const pair<U1, U2>&);   // 仅当 sizeof...(Types) == 2
    template<class U1, class U2>
      constexpr explicit(/* 查看描述 */)
        tuple(pair<U1, U2>&&);        // 仅当 sizeof...(Types) == 2
    // allocator-extended constructors
    template<class Alloc>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a);
    template<class Alloc>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, const Types&...);
    template<class Alloc, class... UTypes>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, UTypes&&...);
    template<class Alloc>
      constexpr tuple(allocator_arg_t, const Alloc& a, const tuple&);
    template<class Alloc>
      constexpr tuple(allocator_arg_t, const Alloc& a, tuple&&);
    template<class Alloc, class... UTypes>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, const tuple<UTypes...>&);
    template<class Alloc, class... UTypes>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, tuple<UTypes...>&&);
    template<class Alloc, class U1, class U2>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&);
    template<class Alloc, class U1, class U2>
      constexpr explicit(/* 查看描述 */)
        tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&&);
    // 元组赋值
    constexpr tuple& operator=(const tuple&);
    constexpr tuple& operator=(tuple&&) noexcept(/* 查看描述 */);
    template<class... UTypes>
      constexpr tuple& operator=(const tuple<UTypes...>&);
    template<class... UTypes>
      constexpr tuple& operator=(tuple<UTypes...>&&);
    template<class U1, class U2>
      constexpr tuple& operator=(const pair<U1, U2>&); // 仅当 sizeof...(Types) == 2
    template<class U1, class U2>
      constexpr tuple& operator=(pair<U1, U2>&&);      // 仅当 sizeof...(Types) == 2
    // tuple 交换
    constexpr void swap(tuple&) noexcept(/* 查看描述 */);
  };
  template<class... UTypes>
    tuple(UTypes...) -> tuple<UTypes...>;
  template<class T1, class T2>
    tuple(pair<T1, T2>) -> tuple<T1, T2>;
  template<class Alloc, class... UTypes>
    tuple(allocator_arg_t, Alloc, UTypes...) -> tuple<UTypes...>;
  template<class Alloc, class T1, class T2>
    tuple(allocator_arg_t, Alloc, pair<T1, T2>) -> tuple<T1, T2>;
  template<class Alloc, class... UTypes>
    tuple(allocator_arg_t, Alloc, tuple<UTypes...>) -> tuple<UTypes...>;
}