Why Swift loops are safe by default - See It in Action

Why Swift loops are safe by default

📖 Scenario: Imagine you have a list of daily temperatures and you want to check which days were warm. You will use a loop to go through the temperatures safely without errors.

🎯 Goal: Build a Swift program that uses a safe loop to check temperatures and print a message for warm days.

📋 What You'll Learn

Create an array called temperatures with exact values: 15, 22, 18, 30, 25

Create a variable called warmThreshold and set it to 20

Use a for loop with variable temp to iterate over temperatures

Inside the loop, use an if statement to check if temp is greater than warmThreshold

Print "Day with temperature X°C is warm." where X is the temperature

💡 Why This Matters

🌍 Real World

Checking temperature data safely is important in weather apps to avoid crashes and errors.

💼 Career

Understanding safe loops helps you write reliable Swift code for apps that handle lists and collections.

1

Create the temperature data

Create an array called temperatures with these exact values: 15, 22, 18, 30, 25

Swift

# Create the temperatures array with values 15, 22, 18, 30, 25
// Your code here

Need a hint?

Use let to create a constant array named temperatures with the given numbers.

2

Set the warm temperature threshold

Create a variable called warmThreshold and set it to 20

Swift

let temperatures = [15, 22, 18, 30, 25]
// Create warmThreshold variable and set it to 20
// Your code here

Need a hint?

Use let to create a constant named warmThreshold with value 20.

3

Loop through temperatures safely

Use a for loop with variable temp to iterate over temperatures. Inside the loop, use an if statement to check if temp is greater than warmThreshold

Swift

let temperatures = [15, 22, 18, 30, 25]
let warmThreshold = 20

// Loop through temperatures and check if temp > warmThreshold
// Your code here

Need a hint?

Use for temp in temperatures to loop. Use if temp > warmThreshold inside the loop.

4

Print warm days

Inside the if statement, write print("Day with temperature \(temp)°C is warm.") to display the message

Swift

let temperatures = [15, 22, 18, 30, 25]
let warmThreshold = 20

for temp in temperatures {
    if temp > warmThreshold {
        // Print warm day message here
    }
}

Need a hint?

Use print("Day with temperature \(temp)°C is warm.") inside the if block.