std::chrono::month::ok

 

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std::chrono::month

Member functions

month::month

month::operator++month::operator--

month::operator+=month::operator-=

month::operator unsigned

month::ok

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

Helper classes

formatter<std::chrono::month>

 

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

Checks if the month value stored in *this is in the valid range, i.e., [1, 12].

Return value

true if the month value stored in *this is in the range [1, 12]. Otherwise false.

Example

Run this code

#include <iostream>
#include <chrono>
 
int main()
{
    for (const unsigned mm : {6u, 0u, 16U}) {
        std::cout << mm << ": ";
        const std::chrono::month m{mm};
        m.ok() ? std::cout << "month is valid\n"
               : std::cout << "month is invalid\n";
    }
}

Output:

6: month is valid
0: month is invalid
16: month is invalid