std::reverse_iterator<Iter>::operator=

 

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std::reverse_iterator

成员函数

reverse_iterator::reverse_iterator

reverse_iterator::operator=

reverse_iterator::base

reverse_iterator::operator*reverse_iterator::operator->

reverse_iterator::operator[]

reverse_iterator::operator++reverse_iterator::operator+reverse_iterator::operator+=reverse_iterator::operator--reverse_iterator::operator-reverse_iterator::operator-=

非成员函数

operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20)

operator+

operator-

iter_move (C++20)

iter_swap (C++20)

make_reverse_iterator (C++14)

 

template< class U > reverse_iterator& operator=( const reverse_iterator<U>& other );		(constexpr 自 C++17 起)

将 other.current 赋值给 current。

仅当 std::is_same_v<U, Iter> 为 false 且 std::convertible_to<const U&, Iter> 和 std::assignable_from<Iter&, const U&> 均被建模时，此重载才参与重载解析。

(自 C++20 起)

参数

other

-

要赋值的迭代器适配器

返回值

*this

示例

运行此代码

#include <iostream>
#include <iterator>
 
int main()
{
    const int a1[]{0, 1, 2};
    int a2[]{0, 1, 2, 3};
    short a3[]{40, 41, 42};
 
    std::reverse_iterator<const int*> it1{std::crbegin(a1)};
    it1 = std::reverse_iterator<int*>{std::rbegin(a2)};   // OK
//  it1 = std::reverse_iterator<short*>{std::rbegin(a3)}; // Compilation error:
                                                          // incompatible pointer types
    std::reverse_iterator<const short*> it2{nullptr};
    it2 = std::rbegin(a3); // OK
//  it2 = std::begin(a3);  // Compilation error: no viable operator= overload
    std::cout << *it2 << '\n';
}

输出

42

缺陷报告

以下行为变更缺陷报告已追溯应用于先前发布的 C++ 标准。

DR	应用于	已发布行为	正确行为
LWG 280	C++98	不允许异构赋值	允许
LWG 3435	C++20	转换赋值运算符未受约束	已约束

参见

(构造函数)

构造一个新的 reverse_iterator (公共成员函数)