Why Swift is strongly typed - See It in Action

Understanding Why Swift is Strongly Typed

📖 Scenario: Imagine you are building a simple app that stores information about fruits and their quantities. You want to make sure the app only accepts the right kind of data for each fruit to avoid mistakes.

🎯 Goal: You will create a small Swift program that shows how Swift uses strong typing to keep data safe and clear. You will declare variables with specific types and see what happens if you try to mix types.

📋 What You'll Learn

Create variables with explicit types

Try to assign wrong types and observe errors

Use type-safe operations

Print the correct values

💡 Why This Matters

🌍 Real World

Strong typing helps developers avoid bugs by making sure data is used correctly, like not mixing numbers and words accidentally.

💼 Career

Understanding strong typing is important for writing safe and reliable Swift code in app development jobs.

1

Create variables with explicit types

Create a variable called appleCount of type Int and set it to 10. Create another variable called fruitName of type String and set it to "Apple".

Swift

# Create the variables 'appleCount' and 'fruitName' with the specified types and values
# Your code here

Need a hint?

Use var to declare variables and specify the type after a colon.

2

Try assigning a wrong type to a variable

Try to assign the string "Twenty" to the variable appleCount. Write the line appleCount = "Twenty" below the previous code.

Swift

var appleCount: Int = 10
var fruitName: String = "Apple"
# Assign the string "Twenty" to appleCount to see the error
# Your code here

Need a hint?

Swift will show an error because you cannot assign a string to an integer variable.

3

Use type-safe operations

Create a new variable called totalApples of type Int and set it to appleCount + 5. This shows adding numbers safely with strong typing.

Swift

var appleCount: Int = 10
var fruitName: String = "Apple"
appleCount = "Twenty"
# Create totalApples by adding 5 to appleCount
# Your code here

Need a hint?

Use the plus sign + to add numbers of the same type.

4

Print the correct values

Print the value of totalApples using print(totalApples).

Swift

var appleCount: Int = 10
var fruitName: String = "Apple"
var totalApples: Int = appleCount + 5
# Print totalApples
# Your code here

Need a hint?

Use print() to show the value on the screen.