std::chrono::year_month_weekday_last::operator sys_days, std::chrono::year_month_weekday_last::operator local_days

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

Converts *this to a std::chrono::time_point representing the same date as this year_month_weekday_last.

1) If ok() is true, returns a sys_days that represents the last weekday() of the year() and month(). Otherwise, the returned value is unspecified.
2) Same as (1), but returns local_days instead of sys_days. Equivalent to local_days(sys_days(*this).time_since_epoch()).

Example

#include <iostream>
#include <chrono>
using namespace std::chrono;
 
int main()
{
    std::cout << std::boolalpha;
 
    constexpr auto ymwdl {Tuesday[last]/11/2021};
    static_assert(static_cast<local_days>(ymwdl) ==
                  static_cast<local_days>(November/30/2021));
    // convert from field-based to serial-based to add days
    constexpr auto sd = static_cast<sys_days>(ymwdl);
    constexpr year_month_day ymd {sd + days(10)};
    std::cout << (ymd == December/10/2021) << '\n';
}

Output:

true