std::chrono:: operator==,<=> (std::chrono::year)

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C-style date and time
std::chrono::year
Defined in header <chrono>
constexpr bool operator == ( const std:: chrono :: year & x,
const std:: chrono :: year & y ) noexcept ;
(1) (since C++20)
constexpr std:: strong_ordering operator <=> ( const std:: chrono :: year & x,
const std:: chrono :: year & y ) noexcept ;
(2) (since C++20)

Compare the two std::chrono::year x and y .

The < , <= , > , >= , and != operators are synthesized from operator <=> and operator == respectively.

Return value

1) int ( x ) == int ( y )
2) int ( x ) <=> int ( y )

Example

Run this code 
#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono;
 
    constexpr year y1{2020};
    constexpr year y2{2021};
 
    std::cout << std::boolalpha << (y1 != y2) << '\n';
 
    static_assert((2020y < 2023y) && (2020y == 2020y) && (2020y <= 2023y) &&
                  (2023y > 2020y) && (2023y != 2020y) && (2023y >= 2020y));
}

Output: 

true
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