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

Since C++20

Header: <chrono>

Compares the two year_month_day values x and y. This is a lexicographical comparison: the year() is compared first, then month(), then day().

# Declarations

constexpr bool operator==( const std::chrono::year_month_day& x,
const std::chrono::year_month_day& y ) noexcept;

(since C++20)

constexpr std::strong_ordering
operator<=>( const std::chrono::year_month_day& x,
const std::chrono::year_month_day& y ) noexcept;

(since C++20)

# Notes

If both x and y represent valid dates (x.ok() && y.ok() == true), the result of the lexicographical comparison is consistent with the calendar order.

# Example

#include <chrono>
 
int main()
{
    constexpr auto ymd1{std::chrono::day(13)/7/1337};
    constexpr auto ymd2{std::chrono::year(1337)/7/13};
    static_assert(ymd1 == ymd2);
    static_assert(ymd1 <= ymd2);
    static_assert(ymd1 >= ymd2);
    static_assert(ymd1 <=> ymd2 == 0);
}