Protocol extensions with default implementations in Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a protocol named Printable.

Swift

protocol [1] {
    func printDescription()
}

Drag options to blanks, or click blank then click option'

ADescribable

BPrintableProtocol

CPrintableExtension

DPrintable

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different protocol name than 'Printable'.

Forgetting the 'protocol' keyword.

The protocol is named Printable to match the requirement.

2fill in blank

medium

Complete the code to add a default implementation for printDescription() in a protocol extension.

Swift

extension Printable {
    func [1]() {
        print("Default description")
    }
}

Drag options to blanks, or click blank then click option'

AshowDescription

Bdescribe

CprintDescription

Ddisplay

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different method name than the protocol requires.

Omitting the method implementation.

The method name must match the protocol requirement: printDescription().

3fill in blank

hard

Fix the error in the struct that conforms to Printable but does not implement printDescription().

Swift

struct Document: Printable {
    var title: String

    func [1]() {
        print("Document title: \(title)")
    }
}

Drag options to blanks, or click blank then click option'

AprintDescription

Bdescribe

CshowTitle

DdisplayTitle

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different method name than the protocol requires.

Not implementing the required method or relying on a wrong name.

The struct must implement printDescription() or use the default implementation.

4fill in blank

hard

Fill both blanks to create a protocol extension that adds a new method and a default implementation.

Swift

extension Printable {
    func [1]() {
        print("Extra info")
    }

    func [2]() {
        print("Default description")
    }
}

Drag options to blanks, or click blank then click option'

AextraInfo

BprintDescription

CshowInfo

Ddescribe

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing method names or using names not matching the protocol.

Not providing default implementation for the protocol method.

The new method is named extraInfo() and the default implementation for the protocol method is printDescription().

5fill in blank

hard

Fill all three blanks to create a struct that uses the default implementation and calls the extra method.

Swift

struct Report: Printable {
    var name: String

    func [1]() {
        print("Report name: \(name)")
    }

    func show() {
        [2]()
        [3]()
    }
}

Drag options to blanks, or click blank then click option'

AprintDescription

BextraInfo

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong method names in the struct.

Not calling the methods correctly inside 'show()'.

The struct overrides printDescription() and calls it and extraInfo() inside show().