Swift Equatable on a protocol

Question

I don\'t think this can be done but I\'ll ask anyway. I have a protocol:

protocol X {}

And a class:

class Y:X {}

Answer 1

You have to implement a protocol extension constrained to your class type. Inside that extension you should implement the Equatable operator.

public protocol Protocolable: class, Equatable
{
    // Other stuff here...
}

public extension Protocolable where Self: TheClass
{
    public static func ==(lhs: Self, rhs:Self) -> Bool 
    {
        return lhs.name == rhs.name
    } 
}


public class TheClass: Protocolable
{
    public var name: String

    public init(named name: String)
    {
        self.name = name
    }
}

let aClass: TheClass = TheClass(named: "Cars")
let otherClass: TheClass = TheClass(named: "Wall-E")

if aClass == otherClass
{
    print("Equals")
}
else
{
    print("Non Equals")
}

But let me recommend you add the operator implementation to your class. Keep It Simple ;-)