std::ranges::stride_view<V>::size

constexpr auto size() requires ranges::sized_range<V>;

constexpr auto size() const requires ranges::sized_range<const V>;

返回元素的数量。

设 base_ 为底层视图，stride_ 为存储的步长值。等价于：

return /*to-unsigned-like*/(/*div-ceil*/(ranges::distance(base_), stride_));

参数

(无)

返回值

元素数量。返回值计算方式相当于表达式

( ranges:: size ( base_ ) / stride_ ) + ( ( ranges:: size ( base_ ) % stride_ ? 1 : 0 ) 。

示例

#include <forward_list>
#include <ranges>
int main()
{
    namespace vs = std::views;
    constexpr static auto v = {1, 2, 3, 4, 5};
    static_assert
    (
        vs::stride(v, 1).size() == 5 and
        vs::stride(v, 2).size() == 3 and
        vs::stride(v, 3).size() == 2 and
        vs::stride(v, 4).size() == 2 and
        vs::stride(v, 5).size() == 1 and
        vs::stride(v, 6).size() == 1
    );
    std::forward_list list{v};
//  auto s = vs::stride(list, 2).size(); // 错误：不是可大小范围
}

参见