FREE TRIAL: Accelerate your app development career with Hacking with Swift+! >>

iOS Developer Interview Questions

What is the difference between if let and guard let?

Suggested approach: Both check and unwrap optionals, but guard forces an early return if its check fails – your code will literally not compile unless you exit the scope. Furthermore, any variables that guard unwraps stay in scope after the guard block, whereas with if let the variables are available only inside the scope.

  Estimated difficulty: Easy

Important notes

  • There are over 150 interview questions in the system. Once you've read the question and come up with a suitable answer, try reading my suggested approach and see if it helps you add more detail.
  • These questions are not designed to be hard; a good interviewer is more interested in generating discussion that lets your ability and interests shine through.
  • If you answer a question with "yes" or "no" you've missed the point – interviewers prefer you to provide reasoning, explanation, or detail, so try to elaborate with examples!
  • If you're looking for detailed technical questions about the language, you should try my Swift tests instead – there are multiple challenges that will work your brain hard.
  • For a whole series of coding challenges, I wrote the perfect book for you: Swift Coding Challenges.

Related questions

See the full list of iOS interview questions

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.