std::chrono::last_spec,std::chrono::last(3)

NAME
std::chrono::last_spec,std::chrono::last - std::chrono::last_spec,std::chrono::last

Synopsis
   Defined in header <chrono>
   struct last_spec
   { (since C++20)
       explicit last_spec() = default;
   };
   inline constexpr last_spec last{}; (since C++20)
   last_spec is an empty tag type that is used in conjunction with other calendar types
   to indicate the last thing in a sequence. Depending on context, it may indicate the
   last day of a month (as in 2018y/February/last, for last day of February 2018, i.e.,
   2018-02-28) or the last day of the week in a month (as in
   2018/February/Sunday[last], for last Sunday of February 2018, i.e., 2018-02-25).

Example
// Run this code
 #include <chrono>
 int main()
 {
     using namespace std::chrono;
     constexpr auto mdl {June/last};
     static_assert(mdl == month_day_last(month(6)));
     constexpr auto ymwdl {year(2023)/December/Tuesday[last]};
     static_assert(ymwdl ==
         year_month_weekday_last(year(2023), month(12), weekday_last(Tuesday)));
 }