Swift Programming Language Quiz

Which statement is used to declare a closure in Swift?

[parameters] -> ReturnType { statements }

(parameters) -> ReturnType { statements }

closure(parameters) { statements }

{ (parameters) -> ReturnType in statements }

None

How do you define a protocol in Swift?

template MyProtocol { … }

interface MyProtocol { … }

protocol MyProtocol { … }

abstract class MyProtocol { … }

None

How do you create a function in Swift that returns a string?

func greet(String) -> { return “Hello” }

func greet() -> String { return “Hello” }

func greet() : String { “Hello” }

func greet(String) { return “Hello” }

None

Which statement correctly creates an immutable array in Swift?

var array = [1, 2, 3]

array = [1, 2, 3]

const array = [1, 2, 3]

let array = [1, 2, 3]

None

Which keyword is used to declare a constant in Swift?

const

final

var

let

None

What is the purpose of the defer statement in Swift?

To execute code just before the current scope exits

To create an asynchronous task

To handle errors

To delay code execution

None

How do you declare an optional string in Swift?

var name: Optional String

var name: String*

var name: String!

var name: String?

None

What does the final keyword do in Swift?

Marks a variable as constant

Declares a variable as optional

Indicates the end of a scope

Prevents a class from being subclassed

None

Which keyword is used for error handling in Swift?

try

catch

handle

throw

None

10.

What is the correct way to check if a dictionary is empty in Swift?

dict.isEmpty

dict.count == 0

dict == nil

dict == [:]

None

11.

What does the self keyword represent in Swift?

The parent class

The main thread

The superclass

The current instance of a class or struct

None

12.

Which Swift feature allows combining strings efficiently?

String Interpolation

String Addition

String Concatenation

String Formatting

None

13.

How do you create an empty dictionary in Swift?

var dict = Dictionary

var dict: Dictionary

var dict = [KeyType: ValueType]()

var dict = [:]

None

14.

How do you create an instance of a class in Swift?

let instance = MyClass()

let instance = create MyClass()

let instance: MyClass

let instance = new MyClass()

None

15.

What is the keyword for creating a class in Swift?

struct

interface

object

class

None

16.

What is Swift primarily used for?

Game development

Data analysis

iOS and macOS application development

Web development

None

17.

What is the syntax to create an array of integers in Swift?

let array: [Integer] = [1, 2, 3]

let array: [Int] = [1, 2, 3]

let array: Array = [1, 2, 3]

let array: Int[] = [1, 2, 3]

None

18.

What does the @objc attribute do in Swift?

Integrates Swift with Java

Optimizes Swift code for performance

Exposes Swift code to Objective-C

Converts Swift code to JavaScript

None

19.

How do you handle optional binding in Swift?

if optionalValue = x { … }

if let x = optionalValue { … }

if optionalValue! { … }

if optionalValue? { … }

None

20.

What is the purpose of the willSet and didSet observers in Swift?

To monitor changes to a property’s value

To create asynchronous tasks

To handle errors

To define constants

None

21.

Which type in Swift represents a collection of key-value pairs?

Set

Tuple

Dictionary

Array

None

22.

Which collection type is unordered and ensures unique elements in Swift?

List

Dictionary

Set

Array

None

23.

How do you declare a computed property in Swift?

var property: Type = { return value }

let property: Type { get { return value } }

var property: Type { get { return value } }

computed var property: Type { return value }

None

24.

What does the ?? operator do in Swift?

Provides a default value for an optional

Combines two strings

Concatenates arrays

Checks for nil values

None

25.

What is the output of print("Hello, \(name)") if name is "John"?

Hello, John

Hello, “John”

Hello, name

Hello, \(name)

None

26.

What is the default access level in Swift?

fileprivate

internal

public

private

None

27.

How do you safely unwrap an optional in Swift?

if let value = optionalValue { … }

if optionalValue == value { … }

if optionalValue != nil { … }

if var value = optionalValue { … }

None

28.

What is the purpose of the typealias keyword in Swift?

To define a type constraint

To create a new name for an existing type

To import types from other modules

To declare a new type

None

29.

What is the purpose of the guard statement in Swift?

To create a loop

To unwrap an optional

To exit a scope if a condition is not met

To define a constant

None

30.

How can you make a property optional in a Swift class?

var property: String*

var property: Optional

var property: String?

var property: Optional String

None

Time’s up

Are you ready to test your knowledge of the Swift programming language? Dive into this engaging quiz and uncover how much you really know. Swift is a powerful and intuitive language for iOS, macOS, watchOS, and tvOS app development. By participating, you’ll gain insights into your strengths and areas that need improvement. Each question is designed to challenge your understanding and help you learn more about Swift. Whether you’re a beginner or an experienced developer, this quiz offers a valuable opportunity to sharpen your skills. Get ready to explore, learn, and boost your Swift expertise. Let’s start!

Swift Programming Language – FAQ

What is Swift programming language?

Swift is a powerful and intuitive programming language created by Apple for building apps on iOS, Mac, Apple TV, and Apple Watch. It’s designed to work with Apple’s Cocoa and Cocoa Touch frameworks, offering developers a modern language with performance and safety features in mind.

Tagged Science