Optional binding with if let in Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to safely unwrap the optional using if let.

Swift

var name: String? = "Alice"
if [1] unwrappedName = name {
    print("Hello, \(unwrappedName)!")
}

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

Alet

Bvar

Cis

Dguard

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'var' instead of 'let' in the if statement.

Using 'is' which is for type checking, not unwrapping.

The 'if let' syntax unwraps the optional safely by binding its value to a new constant.

2fill in blank

medium

Complete the code to unwrap the optional and print the value.

Swift

var age: Int? = 30
if let unwrappedAge = [1] {
    print("Age is \(unwrappedAge)")
}

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

AunwrappedAge

Bage

CoptionalAge

Dself.age

Attempts:

3 left

💡 Hint

Common Mistakes

Using the unwrapped variable name inside the if let condition.

Using a variable name that does not exist.

You unwrap the optional variable 'age' inside the if let statement.

3fill in blank

hard

Fix the error in the optional binding syntax.

Swift

var city: String? = "Paris"
if [1] city = city {
    print("City is \(city)")
}

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

Ais

Bvar

Cguard

Dlet

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' without 'let' or 'var' in the if statement.

Using 'is' which is for type checking.

The correct syntax for optional binding uses 'if let' to unwrap the optional.

4fill in blank

hard

Fill both blanks to unwrap two optionals and print their values.

Swift

var firstName: String? = "John"
var lastName: String? = "Doe"
if [1] first = firstName, [2] last = lastName {
    print("Full name: \(first) \(last)")
}

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

Alet

Bvar

Cis

Dguard

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing 'let' and 'var' in the same if statement.

Using 'is' instead of 'let' for binding.

Both optionals are unwrapped using 'let' in the if statement.

5fill in blank

hard

Fill all three blanks to unwrap an optional, check a condition, and print the result.

Swift

var score: Int? = 85
if [1] unwrappedScore = score, unwrappedScore [2] 80, unwrappedScore [3] 100 {
    print("Great score: \(unwrappedScore)")
}

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

Alet

B>

C<=

Dvar

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'var' instead of 'let' for unwrapping.

Using wrong comparison operators.

Use 'let' to unwrap, then check if score is greater than 80 and less than or equal to 100.