std::chrono::year_month::ok

 

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std::chrono::year_month

Member functions

year_month::year_month

year_month::yearyear_month::month

year_month::operator+=year_month::operator-=

year_month::ok

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

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formatter<std::chrono::year_month>

 

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

Checks if the year and month values stored in this object are valid.

Return value

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

Example

Run this code

#include <iostream>
#include <chrono>
using namespace std::chrono_literals;
 
int main()
{
    std::cout << std::boolalpha;
 
    constexpr std::chrono::year_month ym1 {3030y, std::chrono::July};
    std::cout << ym1.ok() << ' ';
 
    constexpr std::chrono::year_month ym2 {std::chrono::year(2020)/16};
    std::cout << ym2.ok() << '\n';
}

Output:

true false