std::counted_iterator<I>::operator*,->

 

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std::counted_iterator

成员函数

counted_iterator::counted_iterator

counted_iterator::operator=

counted_iterator::base

counted_iterator::count

counted_iterator::operator*counted_iterator::operator->

counted_iterator::operator[]

counted_iterator::operator++counted_iterator::operator++(int)counted_iterator::operator+counted_iterator::operator+=counted_iterator::operator--counted_iterator::operator--(int)counted_iterator::operator-counted_iterator::operator-=

非成员函数

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

operator==(default_sentinel_t) (C++20)

operator+ (C++20)

operator- (C++20)

operator-(default_sentinel_t) (C++20)

iter_move (C++20)

iter_swap (C++20)

辅助类

iterator_traits<std::counted_iterator> (C++20)

 

constexpr decltype(auto) operator*();	(1)	(自 C++20 起)
constexpr decltype(auto) operator*() const     requires /*dereferenceable*/<const I>;	(2)	(自 C++20 起)
constexpr auto operator->() const noexcept     requires std::contiguous_iterator<I>;	(3)	(自 C++20 起)

1,2) 返回对当前元素的引用。如果 this->count() <= 0，则行为未定义。函数体等效于 return *current;.

3) 返回指向当前元素的指针。函数体等效于 return std::to_address(current);.

参数

(无)

返回值

对当前元素的引用或指针。

示例

运行此代码

#include <complex>
#include <iostream>
#include <iterator>
using std::operator""i;
 
int main()
{
    const auto il = {1.i, 2.i, 3.i, 4.i, 5.i};
 
    for (std::counted_iterator i{il.begin() + 1, 3}; i != std::default_sentinel; ++i)
        std::cout << *i << ' ';
    std::cout << '\n';
 
    for (std::counted_iterator i{il.begin() + 1, 3}; i != std::default_sentinel; ++i)
        std::cout << i->imag() << ' ';
    std::cout << '\n';
}

输出

(0,2) (0,3) (0,4)
2 3 4

参见

operator[] (C++20)

按索引访问元素 (公共成员函数)