Ordered

Built-in trait · Adopted with with Ordered

A type that adopts Ordered says which of two values comes first. Its values can then be compared with <, <=, >, and >=, sorted, and given to min and max.

struct Version with Ordered, Textual {
    const major: Int
    const minor: Int

    @override
    func compare(other: Version): Int {
        if self.major != other.major {
            return self.major - other.major
        }
        return self.minor - other.minor
    }

    @override
    func to_string(): String {
        return "#{self.major}.#{self.minor}"
    }
}

print(Version(1, 10) > Version(1, 9))                      # prints true
print([Version(2, 0), Version(1, 5)].sort())               # prints [1.5, 2.0]

compare(other: Self): Int

A negative number when this value comes before other, zero when they are in the same place, and a positive number when it comes after. Only the sign matters.

Emerald’s own types that have an order adopt it: Date, Time, and Duration, among others.