Equality.swift

enum Equality<T: Equatable> {
    case equal(T)
    case notEqual
}

func == <T: Equatable>(lhs: T, rhs: T) -> Equality<T> {
    if lhs == rhs {
        return .equal(lhs)
    } else {
        return .notEqual
    }
}

func == <T: Equatable>(rhs: Equality<T>, lhs: T) -> Bool {
    switch rhs {
    case .equal(let value):
        return lhs == value
    case .notEqual:
        return false
    }
}
infix operator ==: myPrecedence
precedencegroup myPrecedence {
    higherThan: AssignmentPrecedence
    associativity: left
}