struct Person {
    var fullName: String
    var email: String
    var age: Int
}

var someUser = Person(fullName: "Kristijan Vidovic", email: "kristijan.vidovic@gmail.hr", age: 23)

var anotherUser = someUser

someUser.email = "kvidovic@gmail.hr"
anotherUser.email //It's still kristijan.vidovic@gmail.hr
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class Person {
    var fullName: String
    var email: String
    var age: Int

    init(name: String, email: String, age: Int) {
        self.fullName = name
        self.email = email
        self.age = age
    }
}

var somePerson = Person(name: "Kristijan Vidovic", email: "kristijan.vidovic@gmail.com", age: 23)
var anotherPerson = somePerson

somePerson.email = "kvidovic@gmail.hr"
anotherPerson.email //It also changed to kvidovic@gmail.hr