TEAM LICENSES: Save money and learn new skills through a Hacking with Swift+ team license >>

Unwrapping with guard

Question 1/12: This code will print a message – true or false?

Hint: Click to show.

func double(number: Int?) -> Int? {
	guard let number = number else {
		return nil
	return number * 2
let input = 5
if let doubled = double(number: input) {
	print("\(input) doubled is \(doubled).")

Return to Review Menu

Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code
Unknown user

You are not logged in

Log in or create account

Link copied to your pasteboard.