Default parameter values in Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a function with a default parameter value.

Swift

func greet(name: String = [1]) {
    print("Hello, \(name)!")
}
greet()

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

A"User"

B"Guest"

C"Friend"

D"Visitor"

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to put the default value in quotes.

Using a colon instead of an equals sign for the default value.

The default value for the parameter name is set to "Guest". Calling greet() without arguments prints "Hello, Guest!".

2fill in blank

medium

Complete the code to call the function with a custom argument.

Swift

func greet(name: String = "Guest") {
    print("Hello, \(name)!")
}
greet([1])

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

A"Visitor"

BVisitor

Cname

D"name"

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the argument without quotes.

Passing the parameter name instead of a value.

The function is called with the argument "Visitor" (a string in quotes). This prints "Hello, Visitor!".

3fill in blank

hard

Fix the error in the function definition by completing the default parameter value.

Swift

func multiply(number: Int = [1]) -> Int {
    return number * 2
}
print(multiply())

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

Anil

B"2"

Cnumber

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string "2" instead of integer 2.

Using nil as a default value for a non-optional parameter.

The default value must be an integer (2), not a string or nil. This allows calling multiply() without arguments.

4fill in blank

hard

Fill both blanks to define a function with two parameters, one with a default value.

Swift

func describe(age: Int, city: String = [1]) {
    print("Age: \(age), City: \(city)")
}
describe(age: [2])

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

A"Unknown"

B30

C"Unknown City"

Dage

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number as a default for a String parameter.

Not providing the required age argument in the function call.

The parameter city has a default value "Unknown". The function is called with age: 30. The output is "Age: 30, City: Unknown".

5fill in blank

hard

Fill all three blanks to create a function with default parameters and call it with custom arguments.

Swift

func order(item: String = [1], quantity: Int = [2], price: Double = [3]) {
    print("Order: \(quantity) \(item)(s) at $\(price) each")
}
order(item: "Book", quantity: 3, price: 12.99)

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

A"Pen"

B1

C9.99

D"Notebook"

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong types for default values.

Not matching the parameter order in the function call.

The function order has default values: item = "Notebook", quantity = 1, price = 9.99. The call overrides all defaults with custom values.