std::chrono::weekday_last:: ok

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C++
Utilities library
General utilities
Relational operators (deprecated in C++20)
Date and time utilities
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chrono I/O
(C++20)
C-style date and time
std::chrono::weekday_last
constexpr bool ok ( ) const noexcept ;
(since C++20)

Checks if the weekday object stored in * this is valid.

Return value

weekday ( ) . ok ( )

Example

Run this code 
#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto wdl{std::chrono::Tuesday[std::chrono::last]};
    std::cout << (wdl.ok()) << ' ';
 
    wdl = {std::chrono::weekday(42)[std::chrono::last]};
    std::cout << (wdl.ok()) << '\n';
}

Output: 

true false
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