std::chrono::year::ok

 

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std::chrono::year

Member functions

year::year

year::operator++year::operator--

year::operator+=year::operator-=

year::operator+year::operator-

year::is_leap

year::operator int

year::ok

year::min

year::max

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operator==operator<=>

operator+operator-

operator<<

from_stream

operator""y

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formatter<std::chrono::year>

 

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

Run this code

#include <iostream>
#include <iomanip>
#include <chrono>
 
int main()
{
    for (const int i : {2020, 0x8000, 0x8001, 0xFFFF, 0x18000}) {
        const std::chrono::year y{i};
        std::cout << std::boolalpha
            << "input year: " << std::setw(6) << i
            << " │ internal value: " << std::setw(7) << static_cast<int>(y)
            << " │ ok(): " << y.ok() << '\n';
    }
}

Possible output:

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