std::chrono::year::ok

constexpr bool ok() const noexcept;

(since C++20)

Checks if the year value stored in *this is in the valid range, i.e., [-32767, 32767].

Return value

true if the year value stored in *this is in the range [-32767, 32767]. Otherwise false.

Possible implementation

See the implementations in libstdc++, libc++, and Howard Hinnant's date.h.

class Year
{
    short year_;   // exposition-only
 
public:
 
    bool ok() const noexcept { return year_ != std::numeric_limits<short>::min(); }
 
    /*...*/
};

Example

#include <chrono>
#include <iomanip>
#include <iostream>
 
int main()
{
    std::cout << "input year │ internal value │ ok()\n" << std::boolalpha;
 
    for (const int i : {2020, 0x8000, 0x8001, 0xFFFF, 0x18000})
    {
        const std::chrono::year y{i};
        std::cout << std::setw(10) << i << " │ "
                  << std::setw(14) << static_cast<int>(y) << " │ "
                  << y.ok() << '\n';
    }
}

Possible output:

input year │ internal value │ ok()
      2020 │           2020 │ true
     32768 │         -32768 │ false
     32769 │         -32767 │ true
     65535 │             -1 │ true
     98304 │         -32768 │ false

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