NAME¶

std::chrono::year_month_day_last::operatorsys_days, - std::chrono::year_month_day_last::operatorsys_days,

Synopsis¶

constexpr operator std::chrono::sys_days() const noexcept; (1) (since C++20)
constexpr explicit operator std::chrono::local_days() const (2) (since C++20)
noexcept;

Converts *this to a std::chrono::time_point representing the same date as this
year_month_day_last. This is equivalent to composing a year_month_day from year(),
month() and day() and converting that year_month_day to the destination type.

1) Equivalent to std::chrono::sys_days(year()/month()/day()).
2) Equivalent to std::chrono::local_days(year()/month()/day()).

Example¶

// Run this code

#include <array>
#include <chrono>
#include <iostream>
#include <string_view>
using namespace std::chrono;
using namespace std::literals;

int main()
{
constexpr std::chrono::year y{2023y};
constexpr std::array quarters{"1st"sv, "2nd"sv, "3rd"sv, "4th"sv};
constexpr auto mq{12 / 4}; // months per quarter

std::cout << "In year " << static_cast<int>(y) << '\n';
for (auto q = 1; q < 5; ++q)
{
const auto ls = y / std::chrono::month(q * mq) / Sunday[last];
const auto ld = y / std::chrono::month(q * mq) / last;
// subtract last Sunday from last day for day of week
const auto index = (sys_days(ld) - sys_days(ls)).count();
std::cout << "The " << quarters[q - 1] << " quarter ends on a "
<< std::chrono::weekday(index) << '\n';
}
}

Output:¶

In year 2023
The 1st quarter ends on a Fri
The 2nd quarter ends on a Fri
The 3rd quarter ends on a Sat
The 4th quarter ends on a Sun

See also¶

operator sys_days converts to a std::chrono::time_point
operator local_days (public member function of std::chrono::year_month_day)