Typealias for custom naming in Swift - Mini Project: Build & Apply

Typealias for custom naming

📖 Scenario: Imagine you are creating a simple app that tracks distances in kilometers. You want to make your code easier to read by giving a custom name to the Double type that represents distances.

🎯 Goal: You will create a typealias called Distance for Double, then use it to declare variables and print their values.

📋 What You'll Learn

Create a typealias named Distance for the Double type

Declare a variable called homeToSchool of type Distance with the value 3.5

Declare a variable called schoolToPark of type Distance with the value 1.2

Calculate the total distance by adding homeToSchool and schoolToPark

Print the total distance using print

💡 Why This Matters

🌍 Real World

Using <code>typealias</code> helps make code easier to read and understand by giving meaningful names to types, especially in apps dealing with measurements or complex data.

💼 Career

Many software jobs require writing clear and maintainable code. Knowing how to use <code>typealias</code> is a simple way to improve code clarity and teamwork.

1

Create a typealias for Distance

Write typealias Distance = Double to create a new name Distance for the type Double.

Swift

# Your code here

Need a hint?

Use the typealias keyword followed by the new name, an equals sign, and the existing type.

2

Declare distance variables using Distance

Declare a variable called homeToSchool of type Distance and set it to 3.5. Then declare a variable called schoolToPark of type Distance and set it to 1.2.

Swift

typealias Distance = Double
# Declare homeToSchool and schoolToPark variables here

Need a hint?

Use var keyword, variable name, colon, type Distance, equals sign, and the value.

3

Calculate total distance

Create a variable called totalDistance of type Distance and set it to the sum of homeToSchool and schoolToPark.

Swift

typealias Distance = Double

var homeToSchool: Distance = 3.5
var schoolToPark: Distance = 1.2
# Calculate totalDistance here

Need a hint?

Add the two variables and assign the result to totalDistance with type Distance.

4

Print the total distance

Write print(totalDistance) to display the total distance on the screen.

Swift

typealias Distance = Double

var homeToSchool: Distance = 3.5
var schoolToPark: Distance = 1.2

var totalDistance: Distance = homeToSchool + schoolToPark
# Print totalDistance here

Need a hint?

Use the print function with totalDistance inside the parentheses.