std::chrono::year_month::year, std::chrono::year_month::month
From cppreference.com
                    
                                        
                    < cpp | chrono | year month
                    
                                                            
                    |   constexpr std::chrono::year year() const noexcept;  | 
(1) | (since C++20) | 
|   constexpr std::chrono::month month() const noexcept;  | 
(2) | (since C++20) | 
Retrieves the year and month values stored in this year_month object.
Return value
1) Returns the stored std::chrono::year value.
2) Returns the stored std::chrono::month value.
Example
Run this code
#include <chrono> #include <iostream> int main() { std::cout << std::boolalpha; constexpr auto ym{std::chrono::year(2021)/std::chrono::July}; std::cout << (ym.year() == std::chrono::year(2021)) << ' '; std::cout << (ym.month() == std::chrono::month(7)) << '\n'; }
Output:
true true