std::chrono::weekday::ok

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C-style date and time

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

Checks if the weekday value stored in *this is in the valid range, i.e., [0, 6].

Return value

true if the weekday value stored in *this is in the range [0, 6]. Otherwise false.

Example

Run this code

#include <iostream>
#include <chrono>
 
int main()
{
    std::chrono::weekday wd1{1}; // Monday is 1
    std::cout << wd1.c_encoding();
 
    if (wd1.ok()) {
        std::cout << " is a valid weekday.\n";
    } else {
        std::cout << " is an invalid weekday!\n";
    }
 
    std::chrono::weekday wd2{42};
    std::cout << wd2.c_encoding()
              << (wd2.ok() ? " is a valid weekday.\n"
                           : " is an invalid weekday!\n");
}

Output:

1 is a valid weekday.
42 is an invalid weekday!

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Technical Specifications

Member functions
weekday::weekday
weekday::operator++weekday::operator--
weekday::operator+=weekday::operator-=
weekday::c_encodingweekday::iso_encoding
weekday::ok
weekday::operator[]
Nonmember functions
operator==
operator+operator-
operator<<
from_stream
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formatter<std::chrono::weekday>

std::chrono::weekday::ok

Return value

Example

See also

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