constexpr auto size() requires ranges::sized_range<V>;
(1) (since C++20)
constexpr auto size() const requires ranges::sized_range<const V>;
(2) (since C++20)

Returns the number of elements, which is the smaller of the count passed to the constructor and the size of the underlying view.

Let base_ be the underlying view, count_ be the number passed to the constructor (​0​ if default constructed). Equivalent to.

auto n = ranges::size(base_);
return ranges::min(n, static_cast<decltype(n)>(count_));



Return value

The number of elements.


#include <ranges>
#include <iostream>
int main()
    constexpr int arr[] {1, 2, 3};
    for (int i = 0; i != 6; ++i) {
        const auto tv = std::ranges::take_view{arr, i};
        std::cout << tv.size() << ' ';


0 1 2 3 3 3

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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