源代码：
// //引用类型的比较.swift // // Created by chenzhen on 16/8/14. // From 大连东软信息学院 // Copyright © 2016年 zhen7216. All rights reserved. // import Foundation class Employee { var no: Int = 0 var name: String = "" var job: String? var salary: Double = 0 var dept: Department? } struct Department { var no: Int = 0 var name: String = "" } //运算符的重载 func ==(i: Department, r: Department) -> Bool { return i.name == r.name && i.no == r.no } func !=(i: Department, r: Department) -> Bool { return i.name != r.name || i.no != r.no } let emp1 = Employee() emp1.no = 1000 emp1.name = "Martin" emp1.job = "Salesman" emp1.salary = 1250 let emp2 = Employee() emp2.no = 1000 emp2.name = "Martin" emp2.job = "Salesman" emp2.salary = 1250 if emp1 === emp2 { print("emp1 === emp2") } if emp1 === emp1 { print("emp1 === emp1") } var dept1 = Department() dept1.no = 10 dept1.name = "Sales" var dept2 = Department() dept2.no = 10 dept2.name = "Sales" if dept1 == dept2 { print("dept1 == dept2") } else { print("dept1 != dept2") } 运行结果：
