constexpr auto size() requires ranges::sized_range<V>;
(since C++23)
constexpr auto size() const requires ranges::sized_range<const V>;
(since C++23)

Returns the number of elements.

Let base_ be the underlying view and stride_ be the stored stride value. Equivalent to:

return __to_unsigned_like(__div_ceil(ranges::distance(base_), stride_));



Return value

The number of elements. The returned value is calculated as if by expression.

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


A link to test: Compiler Explorer.

#include <ranges>
#include <forward_list>
int main()
    namespace vs = std::views;
    constexpr static auto v = {1, 2, 3, 4, 5};
        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(); // Error: not a sized_range

See also

returns an integer equal to the size of a range
(customization point object)
returns a signed integer equal to the size of a range
(customization point object)

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