标准库头文件 <tuple> (C++11)
来自 cppreference.com
此头文件是 通用实用工具 库的一部分。
包含 | ||
(C++20) |
三路比较运算符 支持 | |
类 | ||
(C++11) |
实现固定大小的容器,它保存可能不同类型的元素 (类模板) | |
(C++11) |
获取类似元组类型的元素数量 (类模板) | |
(C++11) |
获取类似元组类型的元素类型 (类模板) | |
(C++11) |
获取大小 一个 | |
获取指定元素的类型 (类模板特化) | ||
特化 std::uses_allocator 类型特征 (类模板特化) | ||
常量 | ||
(C++11) |
使用 tie 解包 tuple 时跳过元素的占位符(常量) | |
函数 | ||
(C++11) |
创建由参数类型定义的类型的 tuple 对象(函数模板) | |
(C++11) |
创建 tuple 的左值引用或将元组解包到单个对象 (函数模板) | |
(C++11) |
创建 转发引用 的 tuple (函数模板) | |
(C++11) |
通过连接任意数量的元组来创建一个 tuple (函数模板) | |
(C++11) |
元组访问指定元素 (函数模板) | |
(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20) |
按字典顺序比较元组中的值 (函数模板) | |
(C++11) |
特化 std::swap 算法 (函数模板) | |
(C++17) |
使用元组参数调用函数 (函数模板) | |
(C++17) |
使用元组参数构造对象 (函数模板) |
[编辑] 概述
#include <compare> namespace std { // class template tuple template<class... Types> class tuple; // tuple creation functions inline constexpr /* unspecified */ 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&&...); // calling a function with a tuple of arguments 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; // not defined 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; // not defined 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; // element access 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... Types> 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... Types> 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; // relational operators 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...>&); // allocator-related traits 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(/* see description */); // tuple helper classes template<class T> inline constexpr size_t tuple_size_v = tuple_size<T>::value; } // 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>; }
[编辑] 类模板 std::tuple
namespace std { template<class... Types> class tuple { public: // tuple construction constexpr explicit(/* see description */) tuple(); constexpr explicit(/* see description */) tuple(const Types&...); // only if sizeof...(Types) >= 1 template<class... UTypes> constexpr explicit(/* see description */) tuple(UTypes&&...); // only if sizeof...(Types) >= 1 tuple(const tuple&) = default; tuple(tuple&&) = default; template<class... UTypes> constexpr explicit(/* see description */) tuple(const tuple<UTypes...>&); template<class... UTypes> constexpr explicit(/* see description */) tuple(tuple<UTypes...>&&); template<class U1, class U2> constexpr explicit(/* see description */) tuple(const pair<U1, U2>&); // only if sizeof...(Types) == 2 template<class U1, class U2> constexpr explicit(/* see description */) tuple(pair<U1, U2>&&); // only if sizeof...(Types) == 2 // allocator-extended constructors template<class Alloc> constexpr explicit(/* see description */) tuple(allocator_arg_t, const Alloc& a); template<class Alloc> constexpr explicit(/* see description */) tuple(allocator_arg_t, const Alloc& a, const Types&...); template<class Alloc, class... UTypes> constexpr explicit(/* see description */) 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(/* see description */) tuple(allocator_arg_t, const Alloc& a, const tuple<UTypes...>&); template<class Alloc, class... UTypes> constexpr explicit(/* see description */) tuple(allocator_arg_t, const Alloc& a, tuple<UTypes...>&&); template<class Alloc, class U1, class U2> constexpr explicit(/* see description */) tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&); template<class Alloc, class U1, class U2> constexpr explicit(/* see description */) tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&&); // tuple assignment constexpr tuple& operator=(const tuple&); constexpr tuple& operator=(tuple&&) noexcept(/* see description */); 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>&); // only if sizeof...(Types) == 2 template<class U1, class U2> constexpr tuple& operator=(pair<U1, U2>&&); // only if sizeof...(Types) == 2 // tuple swap constexpr void swap(tuple&) noexcept(/* see description */); }; 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...>; }