NAME¶

std::ranges::cartesian_product_view::end - std::ranges::cartesian_product_view::end

Synopsis¶

constexpr iterator<false> end()

requires ((!__simple_view<First> || ... || !__simple_view<Vs>) (1) (since C++23)
&&

__cartesian_product_is_common<First, Vs...>);
constexpr iterator<true> end() const
requires __cartesian_product_is_common<const First, const (2) (since C++23)
Vs...>;
constexpr std::default_sentinel_t end() const noexcept; (3) (since C++23)

Returns an iterator or a sentinel representing the end of the
cartesian_product_view.

Let bases_ be the underlying tuple of views.

1,2) Let:
* __is_const be true for the const-qualified overload, and false otherwise;
* __is_empty be true if the expression ranges::empty(rng) is true for any rng
among the underlying ranges except the first one and false otherwise; and
* __begin_or_first_end(rng) be expression-equivalent to __is_empty ?
ranges::begin(rng) : __cartesian_common_arg_end(rng) if rng is the first
underlying range and ranges::begin(rng) otherwise.

Equivalent to:

auto check = [](auto& rng) { return __begin_or_first_end(rng); };
return iterator<__is_const>(__tuple_transform(check, bases_));

3) Equivalent to: return std::default_sentinel;.

Parameters¶

(none)

Return value¶

An iterator to the element following the last element, or a sentinel which compares
equal to the end iterator.

Example¶

// Run this code

#include <array>
#include <format>
#include <iostream>
#include <ranges>
#include <string_view>
#include <tuple>
using namespace std::literals;

int main()
{
constexpr auto a = std::array{ "bool"sv, "goto"sv, "extern"sv, "long"sv }; /*
^ ^ ^ ^ */
constexpr auto v = std::ranges::cartesian_product_view(a[0], a[1], a[2], a[3]);

constexpr std::tuple<char const&,
char const&,
char const&,
char const&> last{*(v.end() - 1)};

std::cout << std::format("{}{}{}{}{}",
std::get<0>(last),
std::get<1>(last),
std::get<2>(last),
std::get<3>(last), '\n');
}

Output:¶

long

See also¶

begin returns an iterator to the beginning
(C++23) (public member function)
ranges::end returns a sentinel indicating the end of a range
(C++20) (customization point object)