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

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< cpp‎ | chrono‎ | day
 
 
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Defined in header <chrono>
constexpr bool operator==( const std::chrono::day& x,
                           const std::chrono::day& y ) noexcept;
(1) (since C++20)
constexpr std::strong_ordering operator<=>( const std::chrono::day& x,
                                            const std::chrono::day& y ) noexcept;
(2) (since C++20)

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

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

[edit] Return value

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

[edit] Example

#include <chrono>
#include <iostream>
 
int main()
{
    constexpr std::chrono::day x{13}, y{31};
    static_assert(x != y);
 
    if constexpr (constexpr auto res = x <=> y; res < 0)
        std::cout << "x is less than y\n";
    else if constexpr (res > 0)
        std::cout << "x is greater than y\n";
    else
        std::cout << "x and y are equal\n";
 
    using namespace std::literals::chrono_literals;
 
    static_assert
    (
        (6d < 9d) && (6d == 6d) && (6d <= 9d) &&
        (9d > 6d) && (9d != 6d) && (9d >= 6d)
    );
}

Output:

x is less than y