std::chrono::month_day::ok

 

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std::chrono::month_day

Member functions

month_day::month_day

month_day::monthmonth_day::day

month_day::ok

Nonmember functions

operator==operator<=>

operator<<

from_stream

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formatter<std::chrono::month_day>

hash<std::chrono::month_day> (C++26)

 

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

Determines whether this month_day stores a valid month-day combination.

The combination is valid if month() represents a valid month (month().ok() == true), unsigned{day()} >= 1, and unsigned{day()} <= D, where D is the number of days in the month represented by month(). The number of days in February is considered to be 29.

Return value

true if the month and day combination is valid, otherwise false.

Example

Run this code

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    constexpr auto md1{std::chrono::July/15};
    std::cout << (md1.ok()) << ' ';
    constexpr std::chrono::month_day md2{std::chrono::month(14), std::chrono::day(42)};
    std::cout << (md2.ok()) << ' ';
    constexpr auto md3{std::chrono::February/29};
    std::cout << (md3.ok()) << '\n';
}

Output:

true false true