Deinitializers for cleanup in Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a deinitializer in a Swift class.

Swift

class FileHandler {
    init() {
        print("File opened")
    }
    [1] {
        print("File closed")
    }
}

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

Adestroy

Binit

Cfunc cleanup()

Ddeinit

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'init' instead of 'deinit' for cleanup.

Trying to name the deinitializer as a normal function.

The deinit keyword defines a deinitializer in Swift, which runs when an instance is about to be deallocated.

2fill in blank

medium

Complete the code to print a message when the object is deallocated.

Swift

class Connection {
    init() {
        print("Connected")
    }
    deinit {
        [1]("Disconnected")
    }
}

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Arelease

Bprint

Clog

Ddisconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-existent function like 'release' or 'disconnect'.

Forgetting to call a function to output the message.

The print function outputs text to the console in Swift.

3fill in blank

hard

Fix the error in the deinitializer syntax.

Swift

class Logger {
    [1] {
        print("Logger destroyed")
    }
}

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Ainit

Bdeinit()

Cdeinit

Dfunc deinit()

Attempts:

3 left

💡 Hint

Common Mistakes

Adding parentheses after 'deinit'.

Using 'func' keyword before 'deinit'.

The deinitializer in Swift is declared with deinit keyword without parentheses or 'func'.

4fill in blank

hard

Fill both blanks to create a class that opens a file and closes it when the object is destroyed.

Swift

class FileManager {
    init() {
        [1]("File opened")
    }
    [2] {
        print("File closed")
    }
}

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

Aprint

Binit

Cdeinit

Dfunc

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'func' keyword before 'deinit'.

Not using 'print' to show messages.

The init method runs when the object is created, and deinit runs when it is destroyed. Use print to show messages.

5fill in blank

hard

Fill all three blanks to create a class that tracks resource allocation and cleans up properly.

Swift

class Resource {
    var id: Int
    init(id: Int) {
        self.id = id
        [1]("Resource \(id) allocated")
    }
    [2] {
        [3]("Resource \(id) released")
    }
}

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

Aprint

Bdeinit

Dinit

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'init' instead of 'deinit' for cleanup.

Forgetting to use 'print' to show messages.

Use print to show messages, init to initialize, and deinit to clean up when the object is destroyed.