Handling Optionals in Swift

HandlingOptionals.swift

//: Interview Question - Handling optionals

import UIKit

// There are four common ways to handle optionals
// in Swift

// if let
var myString: String?
myString = "myString"

func printMyString() {
    if let myString = myString {
        print("myString: \(myString)")
    } else {
        print("myString is nil")
    }
}

printMyString()


// guard
var myInt: Int?

func printMyInt() {
    guard let myInt = myInt else { return }
    print("myInt: \(myInt)")
}

printMyInt()


// optional chaining
struct User {
    let name: String
    let password: String
}

var myUser: User?

func printMyUserPassword() {
    let password = myUser?.password
    print("myUser's password: \(password)")
}

printMyUserPassword()


// force unwrap (handle with care)
var myDouble: Double?
myDouble = 12.14

func printMyDouble() {
    print("myDouble: \(myDouble!)")
}

printMyDouble()