std::front_inserter

 

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在标头 <iterator> 定义
template<class Container > std::front_insert_iterator<Container> front_inserter( Container& c );		(C++20 起为 constexpr)

front_inserter 是便利函数模板，为容器 c 构造 std::front_insert_iterator，并拥有从实参类型推导的类型。

参数

c

-

支持 push_front 操作的容器

返回值

能用于向容器 c 开头添加元素的 std::front_insert_iterator。

可能的实现

template<class Container>std::front_insert_iterator<Container> front_inserter( Container& c ){returnstd::front_insert_iterator<Container>(c);}

示例

运行此代码

#include <algorithm>#include <deque>#include <iostream>#include <iterator>#include <vector>   int main(){std::vector<int> v{1, 2, 3, 4, 5};std::deque<int> d;std::copy(v.begin(), v.end(), std::front_inserter(d));for(int n : d)std::cout<< n <<' ';std::cout<<'\n';}

输出：

5 4 3 2 1

参阅

front_insert_iterator	在容器头部插入的迭代器适配器 (类模板)
back_inserter	创建拥有从实参推出的类型的 std::back_insert_iterator (函数模板)
inserter	创建拥有从实参推出的类型的 std::insert_iterator (函数模板)