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std::ranges::take_view<V>::size

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< cpp‎ | ranges‎ | take view
 
 
Ranges library
Range access
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(C++23)

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(until C++23)(C++23)


 
 
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_));

Contents

[edit] Parameters

(none)

[edit] Return value

The number of elements.

[edit] Example

#include <iostream>
#include <ranges>
 
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() << ' ';
    }
    std::cout << '\n';
}

Output:

0 1 2 3 3 3

[edit] See also

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