Namespaces
Variants

std::chrono::year::year

From cppreference.com
 
 
 
 
year() = default;
(1) (since C++20)
constexpr explicit year( int y ) noexcept;
(2) (since C++20)

Constructs a year object.

1) Default constructor leaves the year value uninitialized.
2) If y is in the range [-3276732767], constructs a year object holding the year value y. Otherwise the value held is unspecified.

Example

#include <chrono>
#include <iostream>

int main()
{
    using namespace std::chrono;

    constexpr int leap_years = []
    {
        int count{};
        for (int i{year::min()}; i <= int{year::max()}; ++i)
            if (year{i}.is_leap()) // uses constructor (2)
                ++count;
        return count;
    } ();

    static_assert(15891 == leap_years);

    std::cout << "There are " << leap_years << " leap years in the range ["
              << int(year::min()) << ", " << int(year::max()) << "].\n";
}

Output:

There are 15891 leap years in the range [-32767, 32767].