Labeled statements for nested loops in Swift - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a labeled statement in Swift?

A labeled statement is a name given to a loop or block of code, allowing you to control flow explicitly, especially useful for nested loops.

beginner

How do you define a label for a loop in Swift?

You write the label name followed by a colon before the loop. For example:<br>outerLoop: for i in 1...3 { ... }

intermediate

Why use labeled statements with nested loops?

They let you break or continue an outer loop directly from inside an inner loop, making it easier to control complex loop flows.

beginner

What happens if you use 'break' without a label inside nested loops?

The 'break' will only exit the innermost loop, not the outer loops.

intermediate

Example: How to break out of an outer loop named 'outerLoop' from inside an inner loop?

Use break outerLoop inside the inner loop to exit the outer loop immediately.

How do you label a loop named 'mainLoop' in Swift?

A mainLoop: for i in 1...5 { }

B for mainLoop in 1...5 { }

C label mainLoop for i in 1...5 { }

D for i in 1...5 mainLoop: { }

The correct syntax is to write the label followed by a colon before the loop.

What does 'break outerLoop' do inside nested loops?

A Continues the outer loop

B Exits only the innermost loop

C Exits the loop labeled 'outerLoop'

D Causes a syntax error

'break outerLoop' exits the loop that has the label 'outerLoop'.

If you want to skip the current iteration of an outer loop from inside an inner loop, what do you use?

A continue outerLoop

B skip outerLoop

C break outerLoop

D continue

'continue outerLoop' skips the current iteration of the loop labeled 'outerLoop'.

What happens if you use 'break' without a label inside nested loops?

A Breaks all loops

B Breaks only the innermost loop

C Breaks the outermost loop

D Does nothing

'break' without a label exits only the innermost loop.

Which of these is a valid use of a labeled statement in Swift?

A while true { break outer }

B label outer while true { break }

C while true outer: { break }

D outer: while true { break outer }

Label must be before the loop, and 'break outer' correctly exits the labeled loop.

Explain how labeled statements help control flow in nested loops in Swift.

Think about how you can exit or skip outer loops from inside inner loops.

Write a simple Swift code example using a labeled statement to break out of an outer loop from inside an inner loop.

Use a label before the outer loop and 'break labelName' inside the inner loop.