std::chrono::year_month_weekday_last::ok

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Utilities library
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constexpr bool ok() const noexcept;
(since C++20)

Checks if this object represents a valid date. Since a year_month_weekday_last represents the last weekday of a particular month, it is valid as long as the year, month and weekday are valid.

Return value

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

Example

#include <iostream>
#include <chrono>
using namespace std::chrono;
 
int main()
{
    std::cout << std::boolalpha;
 
    auto ymwdl {Tuesday[last]/11/2020};
    std::cout << (ymwdl.ok()) << ' ';
    ymwdl = Tuesday[last]/-2/2021;
    std::cout << (ymwdl.ok()) << ' ';
    ymwdl += months(0); // Normalize month
    std::cout << (ymwdl.ok()) << '\n';
}

Output:

true false true