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_));
(none).
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() << ' ';
}
}Output:
0 1 2 3 3 3
|
(C++20) | returns an integer equal to the size of a range (customization point object) |
|
(C++20) | returns a signed integer equal to the size of a range (customization point object) |
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