NAME¶

std::ranges::common_view::size - std::ranges::common_view::size

Synopsis¶

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.

Equivalent to return ranges::size(base_);, where base_ is the underlying view.

Parameters¶

(none)

Return value¶

The number of elements.

Example¶

// Run this code

#include <ranges>
#include <string_view>

int main()
{
constexpr static auto v1 = {1, 2, 3, 4, 5};
constexpr auto common1 { v1 | std::views::common };
static_assert(common1.size() == 5);

constexpr auto take3 { v1 | std::views::reverse | std::views::take(3) };
constexpr auto common2 { take3 | std::views::common };
static_assert(common2.size() == 3);

using namespace std::literals;
constexpr static auto v2 = { "∧"sv, "∨"sv, "∃"sv, "∀"sv };
static_assert(std::ranges::views::common(v2).size() == 4);
}

See also¶

ranges::size returns an integer equal to the size of a range
(C++20) (customization point object)
ranges::ssize returns a signed integer equal to the size of a range
(C++20) (customization point object)