How do I create a Set of custom objects (Swift)?

To make set of Person you need to make it conform to Equatable and Hashable protocols:

class Person: Equatable, Hashable {    var Id: Int    var Name: String    init(id: Int, name: String?) {        self.Id = id        self.Name = name ?? ""    }    var hashValue: Int {        get {            return Id.hashValue << 15 + Name.hashValue        }    }}func ==(lhs: Person, rhs: Person) -> Bool {    return lhs.Id == rhs.Id && lhs.Name == rhs.Name}

Then you can use set of persons like this:

var set = Set<Person>()set.insert(Person(id: 1, name: "name"))

With Swift 2.0, Hashable and Equitable is a part of NSObject. All you need to do is to override "isEqual" and "var hash:" for the property of interest. In this case: "Id", Set will exclude Person-objects with identical Ids.

    class Person: NSObject {        var Id: Int        var Name: String        init(id: Int, name: String?) {            self.Id = id            self.Name = name ?? ""        }        override var hash: Int {        return Id.hashValue   }        override func isEqual(object: AnyObject?) -> Bool {            guard let rhs = object as? Person else {                return false            }            let lhs = self            return lhs.Id == rhs.Id        }    }          func mergeArrays(){       let person1 = Person(id: 1, name: "Tom")       let person2 = Person (id: 2, name: "John")       let person3 = Person(id: 3, name: "Adam")       let downloadedPeople  = [person1,person2] //[{NSObject, Id 1, Name "Tom"}, {NSObject, Id 2, Name "John"}]        let peopleStoredLocally = [person1,person3] //[{NSObject, Id 1, Name "Tom"}, {NSObject, Id 3, Name "Adam"}]       let downloadedPeopleSet = Set(downloadedPeople) //{{NSObject, Id 2, Name "John"}, {NSObject, Id 1, Name "Tom"}}       let mergedSet = downloadedPeopleSet.union(peopleStoredLocally) //{{NSObject, Id 2, Name "John"}, {NSObject, Id 3, Name "Adam"}, {NSObject, Id 1, Name "Tom"}}       let mergedArray = Array(mergedSet)//[{NSObject, Id 2, Name "John"}, {NSObject, Id 3, Name "Adam"}, {NSObject, Id 1, Name "Tom"}]    }