Module quiz: Error handling, functional programming and testing :Advanced Programming in Swift (Meta iOS Developer Professional Certificate) Answers 2026

Question 1

Which of the following expressions is used to mark function as throwable?

❌ try throwable()
✅ throws
❌ throw

Explanation: Swift me function ko throwable declare karne ke liye function signature me throws keyword use hota hai.

Question 2

Will the following code run without issues?

❌ No, there cannot be two catch blocks after each other.
❌ Yes, but first catch block will be executed.
✅ Yes, code runs with no issues

Explanation: Swift me ek do ke baad multiple catch blocks allowed hote hain, jab tak syntax sahi ho.

Question 3

Which of the following expressions will convert thrown error into nil value?

❌ try!
❌ try
✅ try?

Explanation: try? error ko handle karke nil return karta hai agar error throw hota hai.

Question 4

Can the following class be thrown as an error?

✅ Yes
❌ No, as it does not extend Error protocol.
❌ No, as classes cannot be thrown as errors.

Explanation: NSError already Error protocol ko conform karta hai, isliye ye throw ho sakta hai.

Question 5

What statement is used to execute code when leaving the current scope?

❌ do
✅ defer
❌ catch

Explanation: defer block tab execute hota hai jab current scope se bahar nikalte hain.

Question 6

What is a multi-recursion?

❌ When a function has a call to itself in the beginning of its implementation.
✅ It’s when function has multiple call to itself in its implementation.
❌ When a function has a call to itself in the end of its implementation.

Explanation: Jab ek function apne aap ko ek se zyada jagah call kare, use multi-recursion kehte hain.

Question 7

Functional programming is when a function can throw an error?

❌ True
✅ False

Explanation: Functional programming ka matlab immutability, pure functions, aur higher-order functions hota hai — error throwing se direct relation nahi.

Question 8

Which of the following functions are higher order functions? (Select all that apply)

✅ map
❌ defer
✅ filter

Explanation: Higher-order functions wo hoti hain jo function ko input ya output ke roop me leti/deti hain — map aur filter dono aisi hi hain.

Question 9

Which library in Xcode allows you to implement unit tests?

❌ XCTestCase
❌ XCTAssert
✅ XCTest

Explanation: XCTest framework unit testing ke liye use hota hai; baaki classes/functions usi ka part hain.

Question 10

Mock can be used instead of a fake.

✅ True
❌ False

Explanation: Testing me mock aur fake dono test doubles hote hain; kai cases me mock fake ka replacement ho sakta hai.

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