std::chrono::last_spec, std::chrono::last
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last_speclast
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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年02月28日) 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年02月25日).
[edit] 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))); }