Protocol extensions for shared behavior in Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a protocol named 'Greetable'.

Swift

protocol [1] {
    func greet() -> String
}

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AGreet

BGreeter

CGreeting

DGreetable

Attempts:

3 left

💡 Hint

Common Mistakes

Using a class or struct name instead of a protocol name.

The protocol name should be 'Greetable' as declared.

2fill in blank

medium

Complete the protocol extension to provide a default implementation for 'greet()'.

Swift

extension Greetable {
    func greet() -> String {
        return [1]
    }
}

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A"Hello!"

BHello

Cgreet()

Dprint("Hello!")

Attempts:

3 left

💡 Hint

Common Mistakes

Returning a function call or printing instead of returning a string.

The default implementation returns the string "Hello!".

3fill in blank

hard

Fix the error by completing the struct declaration that conforms to 'Greetable'.

Swift

struct Person: [1] {
    var name: String
}

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AGreeting

BGreeter

CGreetable

DGreet

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect protocol names or forgetting conformance syntax.

The struct must conform to the 'Greetable' protocol to use its default implementation.

4fill in blank

hard

Fill both blanks to override the default 'greet()' method in the struct.

Swift

extension Person {
    func greet() -> String {
        return [1] + ", " + [2]
    }
}

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A"Hi"

Bname

C"Hello"

Dgreet()

Attempts:

3 left

💡 Hint

Common Mistakes

Using method calls instead of string or property names.

The method returns "Hi, " plus the person's name.

5fill in blank

hard

Fill all three blanks to create a dictionary that maps names to greetings for a list of people.

Swift

let greetings = Dictionary(uniqueKeysWithValues: people.filter({ person in person.name.count [2] 3 && person.greet() [3] "Hello!" }).map({ person in (person.name, person.[1]()) }))

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

Agreet

B>

C!=

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using property 'name' instead of method 'greet' for greetings.

Using wrong comparison operators.

This creates a dictionary where keys are names and values are greetings, filtering names longer than 3 characters and greetings not equal to "Hello!".