std::chrono::year_month_weekday::ok

From cppreference.com
 
C++
 
Utilities library
General utilities
Date and time
Function objects
Formatting library (C++20)
(C++11)
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
(C++20)
Swap and type operations
(C++20)
(C++14)
(C++11)
(C++23)
(C++11)
(C++23)
(C++11)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++11)
(C++17)
(C++17)
(C++23)
Elementary string conversions
(C++17)
(C++17)
(C++17)
 
Date and time utilities
Time point
(C++11)
(C++20)
Duration
(C++11)
Clocks
(C++11)
(C++11)
(C++11)      
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Time of day
(C++20)(C++20)
(C++20)(C++20)
(C++20)

Calendars
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(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++20)
chrono I/O
(C++20)
C-style date and time
 
std::chrono::year_month_weekday
 
constexpr bool ok() const noexcept;
 (since C++20)

Checks if this year_month_weekday object represents a valid date.

Return value

true if this year_month_weekday object represents a valid date, that is, year().ok() && month().ok() && weekday_indexed().ok() is true and there are at least index() weekday()s in the specified year and month. Otherwise false.

Example

Run this code
#include <iostream>
#include <chrono>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto ymwdi {std::chrono::Wednesday[1]/1/2021};
    std::cout << (ymwdi.ok()) << ' ';
    ymwdi = std::chrono::year(2021)/std::chrono::month(1)/
            std::chrono::Wednesday[42];
    std::cout << (ymwdi.ok()) << '\n';
}

Output: 

true false
Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/chrono/year_month_weekday/ok&oldid=146238"