Refined Swift Test - 72+ MCQs: Swift Programming Language Quiz: Test Your Swift Skills

1. Explain the concept of Swift's 'Set' type.

A way to represent a collection of unique, unordered values

A mechanism for defining custom attributes in Swift

A feature for writing concurrent code in Swift

Swift does not have a 'Set' type

2. Which collection type in Swift is unordered and does not allow duplicate elements?

Array

Set

Dictionary

Tuple

3. Explain Swift's 'associatedtype' in protocols.

A keyword for defining Swift functions in protocols

A mechanism for specifying the type of an associated value in Swift

An alternative syntax for defining Swift properties

A way to declare global constants in Swift

4. What is the purpose of the 'break' statement in a loop?

To exit the program

To skip the next iteration

To end the loop prematurely

To start a new loop

5. What is the purpose of the Swift 'enum' type?

To define a set of related values

To declare a constant in Swift

To represent a single value

Swift does not have an 'enum' type

6. Explain the concept of protocol-oriented programming in Swift.

A paradigm emphasizing composition through protocols

A method for writing Swift protocols

An approach to writing procedural Swift code

A way to organize Swift classes hierarchically

7. In Swift, how do you handle errors using the 'try', 'catch', and 'throw' keywords?

try { } catch { } throw { }

throw { } try { } catch { }

try { } throw { } catch { }

catch { } try { } throw { }

8. How can you achieve multithreading in Swift?

By using global variables

Swift does not support multithreading

Through the use of DispatchQueue

By defining multiple classes

9. Which operator is used for equality comparison in Swift?

10. What is the 'nil coalescing operator' (??) used for in Swift?

To unwrap optionals

To force unwrap optionals

To provide a default value for optionals

To create optional chaining

11. What is the correct way to concatenate two strings in Swift?

string1 + string2

string1 .concat(string2)

concatenate(string1, string2)

string1 .append(string2)

12. Which Swift data type is used to store whole numbers?

Double

Int

Float

String

13. What are the benefits of using Swift Optionals?

Reducing the need for unwrapping

Avoiding runtime crashes due to nil values

Improving code clarity and safety

All of the above

14. What is the purpose of Swift's 'defer' statement?

To declare a Swift function

To postpone the execution of a block of code until the end of the current scope

To implement error handling in Swift

To create a global constant in Swift

15. Explain the concept of Swift's 'inout' parameter.

A parameter indicating input in Swift functions

A keyword for defining class inheritance in Swift

A way to pass a value by reference to a function in Swift

Swift does not have an 'inout' parameter

16. How does Swift handle multiple return values from a function?

Through the use of tuples

By using global variables

Swift does not support multiple return values

By defining multiple functions

17. What is the purpose of the 'unowned' keyword in Swift?

To declare a constant

To define an unwrapped optional

To prevent strong reference cycles

To enforce immutability

18. Which Swift data type is used to store decimal numbers?

Int

Double

Float

Decimal

19. What are generics in Swift?

A mechanism for defining custom operators

A feature for writing concurrent code in Swift

A way to write code that can work with any type

A set of predefined mathematical functions in Swift

20. How do you declare a property as 'weak' in Swift?

weak var myProperty: Type?

myProperty weak Type?

let myProperty: weak Type?

var myProperty: weak Type?

Swift MCQ Test 4