Default parameter values in Swift - Mini Project: Build & Apply

Using Default Parameter Values in Swift Functions

📖 Scenario: You are creating a simple greeting app that can say hello to users. Sometimes, users provide their name, and sometimes they don't. You want the app to greet users properly in both cases.

🎯 Goal: Build a Swift function that uses default parameter values to greet users by name or with a generic greeting if no name is given.

📋 What You'll Learn

Create a function called greet that takes one parameter name of type String.

Set a default value for the name parameter to "Guest".

Call the greet function twice: once without any argument and once with the argument "Alice".

Print the greeting message inside the greet function.

💡 Why This Matters

🌍 Real World

Default parameter values are useful in apps where some inputs are optional, like greeting users who may or may not provide their names.

💼 Career

Understanding default parameters helps you write cleaner, more flexible functions, a skill important for Swift developers building user-friendly apps.

1

Create the greet function with a name parameter

Write a Swift function called greet that takes one parameter named name of type String. Inside the function, print the message "Hello, \(name)!".

Swift

# Your code here

Need a hint?

Define a function with func, add a parameter name: String, and use print with string interpolation.

2

Add a default value to the name parameter

Modify the greet function so that the name parameter has a default value of "Guest".

Swift

func greet(name: String = "Guest") {
    print("Hello, \(name)!")
}
# Your code here

Need a hint?

Add = "Guest" after the parameter type to set a default value.

3

Call greet without an argument

Call the greet function without passing any argument.

Swift

func greet(name: String = "Guest") {
    print("Hello, \(name)!")
}
greet()
# Your code here

Need a hint?

Just write greet() to call the function with the default parameter.

4

Call greet with the argument "Alice" and print both greetings

Call the greet function with the argument "Alice" after the call without arguments. The program should print both greetings.

Swift

func greet(name: String = "Guest") {
    print("Hello, \(name)!")
}
greet()
greet("Alice")
# Your code here

Need a hint?

Call greet("Alice") after greet() to see both greetings.