#Swift Syntax
import Foundation
//custom operator
infix operator *** { associativity left }
class Animal:NSObject{
var name:String!
var age:UInt!
weak var spouse:Animal?
init(name:String,age:UInt){
self.name=name
self.age=age
}
func description() ->String{ //to become printable
return "name= \(name) and age=\(age) spouse=\(spouse)"
}
}
func ==(a:Animal,b:Animal)->Bool{
return a.name == b.name && a.age==b.age
}
func *(a:Animal,b:UInt)->Animal{ //multiply the age by number
let age=a.age * b
return Animal(name:a.name,age:age)
}
func *(a:UInt,b:Animal)->Animal{
let age=b.age * a
return Animal(name:b.name,age:age)
}
//custom operator
func ***(a:Animal,b:Animal){ //This simply means they are married
a.spouse=b
//b.spouse=a //This keep crashing the program.y?
}
let dog=Animal(name:"Lucky",age:3)
let cat=Animal(name:"Branson",age:4)
dog *** cat //dog is married to cat
println(cat)
println(dog)
println(dog*3)protocol Animal{
var name:String!{get}
typealias ElementType
func getSiblings() ->[ElementType]
func getMother() -> ElementType?
func getFather() -> ElementType?
func addSibling(sibling:ElementType)
}
class Human:Animal{
let name:String!
let father:Human?
let mother:Human?
var siblings:[Human]=[]
init(name:String,father:Human?=nil,mother:Human?=nil){
self.name=name
self.father=father
self.mother=mother
}
func getSiblings()->[Human]{
return siblings
}
func getMother()->Human?{
return mother?
}
func getFather()->Human?{
return father?
}
func addSibling(sibling: Human) {
siblings.append(sibling)
}
}
func ==<T:Animal>(a:T,b:T)->Bool{
return a.name == b.name //Just for simplicity purpose
}
func compareAnimal<T:Animal,Equatable where T.ElementType: Animal>(a:T, b:T)->Bool{
return a == b
}
let firstMan=Human(name:"Adam")
let firstWoman=Human(name:"Eve")
let firstBorn=Human(name:"Steve",father: firstMan, mother: firstWoman)
println(firstMan == firstWoman)protocol Animal{
typealias Element
func getSiblings() ->[Element]
func getMother() -> Element?
func getFather() -> Element?
func addSibling(sibling:Element)
}
class Human:Animal{
let name:String!
let father:Human?
let mother:Human?
var siblings:[Human]=[]
init(name:String,father:Human?=nil,mother:Human?=nil){
self.name=name
self.father=father
self.mother=mother
}
func getSiblings()->[Human]{
return siblings
}
func getMother()->Human?{
return mother?
}
func getFather()->Human?{
return father?
}
func addSibling(sibling: Human) {
siblings.append(sibling)
}
}
let firstMan=Human(name:"Adam")
let firstWoman=Human(name:"Eve")
let firstBorn=Human(name:"Steve",father: firstMan, mother: firstWoman)func printEqual<T:Equatable>(a:T,b:T){
if a == b{
println("\(a) && \(b) are equal")
}else{
println("\(a) && \(b) are not equal")
}
}
printEqual(1,1)class Person{
let name:String!
let age:UInt!
var phone:PhoneNumber?
init(name:String,age:UInt){
self.name=name
self.age=age
}
}
class PhoneNumber{
var carrier:String
var number:String
init(number:String,carrier:String){
self.number=number
self.carrier=carrier
}
func phoneNumber()->String{
return number
}
}
let jacksparrow=Person(name:"Jack Sparrow",age:32)
//If you comment next line out, it does crash.It only return nil
jacksparrow.phone=PhoneNumber(number:"580-581-CAPTAIN",carrier:"Black Pearl")
let number=jacksparrow.phone?.number
let carrier=jacksparrow.phone?.phoneNumber()
println(number)
println(carrier)class DistanceRun{
let miles:Double!
lazy var kilometers:()->Double={
[unowned self] in //The auto capture self, use owned to avoid strong cycle
return (self.miles * 1.60934)
}
init(miles:Double){
self.miles=miles
}
deinit{
println("Object is being deallocated")
}
}
var distanceRun:DistanceRun?=DistanceRun(miles:2)
println(distanceRun!.kilometers())
distanceRun=nil//use unowned var administrator:Person or weak var school:School? to break the cycle
//unowned is used if reference can never be nil once initialized else use use weak.
class School{
let name:String!
var administrator:Person //use owned to break the cycle
init(name:String,administrator:Person){
self.name=name
self.administrator=administrator
}
deinit{
println("school: \(name) is being deallocated")
}
}
class Person{
let name:String!
let age:UInt!
weak var school:School? //or use weak to break the cycle
init(name:String,age:UInt){
self.name=name
self.age=age
}
deinit{
println("person: \(name) is being deallocated")
}
}
var president:Person?=Person(name:"Drew Gilpin Faust",age:67)
var harvard:School?=School(name:"Harvard University",administrator:president!)
president!.school=harvard //This created string reference cycle
president=nil //if you comment this out only one line will be printed
harvard=nil //if you comment this out, none will be printedclass FileResource{
let resourceLocation:String!
init?(location:String){
if !locationValid(location){
return nil
}
resourceLocation=location
}
func locationValid(location:String)->Bool{
//Implement the algorithm to check if location is valid
return false //or you might return true
}
}
if let fileResource=FileResource(location:"a"){
println("Valid resource created")
}else{
println("Resource could not be created")
}enum Nationality{
case American(Int) //SSN for identification
case British(Int,String) //passport,name
case SouthAfrican(Int,String,UInt) //password,name,age
}
let person=Nationality.American(1234)
switch person{
case let .American(ssn):
println("American with SSN = \(ssn)")
case let .British(passport,name):
println("British citizen with password = \(passport) & name = \(name)")
case let .SouthAfrican(passport,name,age):
println("South African with name=\(name) & age=\(age) & passport = \(passport)")
}let person=("jesus",20)
switch person{
case let(name,age) where name == "jesus":
println("This is baby jesus")
case let(name,age):
println("Name is \(name)")
}var color:String?
var defaultColor:String="White"
let colorOption=color ?? defaultColor
println(colorOption)class Person:Hashable{
var name:String?
var age:UInt?
init(name:String,age:UInt){
self.name=name
self.age=age
}
var hashValue:Int{
return "\(name),\(age)".hashValue
}
}
func ==(lhs:Person,rhs:Person)->Bool{ //You must conform to Equatable protocol
return lhs.hashValue == rhs.hashValue
}
if Person(name:"a",age:18) == Person(name:"a",age:18){
println("Equal yes")
}else{
println("Not equal")
}