Switch statement power in Swift - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a switch statement in Swift?

A switch statement lets you check a value against many possible cases. It helps you choose what code to run based on the value, like a traffic light deciding what color to show.

intermediate

How does Swift's switch differ from other languages?

Swift's switch is very powerful: it must be exhaustive (cover all cases), supports ranges, tuples, and where clauses for conditions, and does not need break statements to stop fall-through.

intermediate

What is the purpose of the where clause in a Swift switch case?

The where clause adds extra conditions to a case. It lets you check more than just the value, like saying 'match this case only if this extra rule is true'.

beginner

Explain how Swift switch handles multiple values in one case.

You can list multiple values separated by commas in one case. This means if the value matches any of them, that case runs. It's like saying 'if the value is this or that, do this'.

beginner

What happens if no case matches in a Swift switch statement?

Swift requires all possible values to be covered. If you don't cover all, you must add a default case to catch anything else. This keeps your code safe and predictable.

In Swift, what keyword is used to add extra conditions to a switch case?

A where

B if

C case

D else

The 'where' keyword lets you add extra conditions to a case in a switch statement.

Which of these is NOT true about Swift's switch statement?

A It can match tuples.

B It must cover all possible values.

C It supports matching ranges.

D It requires a break statement after each case.

Swift switch does NOT require break statements; it automatically stops after each case.

How do you handle values not matched by any case in Swift switch?

A Ignore them.

B Use a default case.

C Use an else statement.

D Use a catch block.

A default case catches any values not matched by other cases.

Can you list multiple values in one Swift switch case?

A No, only one value per case.

B Yes, but only with ranges.

C Yes, separated by commas.

D Only if they are strings.

You can list multiple values separated by commas in one case.

What does it mean that Swift switch is exhaustive?

A All possible values must be handled.

B It runs all cases every time.

C It only works with enums.

D It requires a default case always.

Exhaustive means all possible values must be covered by cases or a default.

Describe how Swift's switch statement can match complex patterns beyond simple values.

Think about how you can check more than just one value.

Explain why Swift requires switch statements to be exhaustive and how you can satisfy this requirement.

Consider what happens if a value doesn't match any case.