std::chrono::year_month_weekday::ok

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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
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