std::chrono::year_month_day_last::ok

From cppreference.com
 
 
 
Date and time utilities
(C++11)
(C++11)
Clocks
(C++20)
                                                  
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Calendars
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Time zones
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
C-style date and time
 
 
constexpr bool ok() const noexcept;
(since C++20)

Checks if *this represents a valid date. Because a year_month_day_last represents the last day of a particular month, it represents a valid date as long as the year and month are valid.

Return value

year().ok() && month().ok()