std::chrono::month_day_last
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header  <chrono>
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|   class month_day_last;  | 
(since C++20) | |
The class month_day_last represents the last day of a specific month, of some yet to be specified year.
month_day_last is a TriviallyCopyable StandardLayoutType.
Member functions
  constructs a month_day_last (public member function)  | |
|    accesses the stored month   (public member function)  | |
|    checks if the stored month is valid   (public member function)  | 
Nonmember functions
   compares two month_day_last objects  (function)  | |
   outputs a month_day_last into a stream (function template)  |