Named arguments for clarity in Kotlin - Mini Project: Build & Apply

Named arguments for clarity

📖 Scenario: You are creating a simple program to calculate the price of a product after applying a discount and adding tax. To make your code clear and easy to read, you will use named arguments when calling functions.

🎯 Goal: Build a Kotlin program that defines a function to calculate the final price of a product using named arguments for clarity. You will create the data, set up a discount rate, use named arguments in the function call, and print the final price.

📋 What You'll Learn

Create a function called calculateFinalPrice with parameters price, discount, and tax.

Use named arguments when calling calculateFinalPrice.

Print the final price with two decimal places.

💡 Why This Matters

🌍 Real World

Using named arguments helps programmers read and understand code easily, especially when functions have many parameters.

💼 Career

Clear code with named arguments is valued in software development jobs because it reduces mistakes and improves teamwork.

1

Create the product price variable

Create a variable called productPrice and set it to 100.0.

Kotlin

# Create a variable called productPrice and set it to 100.0
# Your code here

Need a hint?

Use val productPrice = 100.0 to create the variable.

2

Set the discount rate

Create a variable called discountRate and set it to 0.15 (which means 15%).

Kotlin

val productPrice = 100.0
# Create a variable called discountRate and set it to 0.15
# Your code here

Need a hint?

Use val discountRate = 0.15 to create the discount rate variable.

3

Define the function and use named arguments

Define a function called calculateFinalPrice that takes three Double parameters: price, discount, and tax. It should return the final price after applying the discount and adding tax. Then, create a variable called finalPrice and call calculateFinalPrice using named arguments: price = productPrice, tax = 0.08, and discount = discountRate.

Kotlin

val productPrice = 100.0
val discountRate = 0.15
# Define the function calculateFinalPrice and call it with named arguments
# Your code here

Need a hint?

Define the function with the three parameters and return the final price. Use named arguments in the function call for clarity.

4

Print the final price

Print the value of finalPrice rounded to two decimal places using println. Use "%.2f".format(finalPrice) to format the output.

Kotlin

val productPrice = 100.0
val discountRate = 0.15

fun calculateFinalPrice(price: Double, discount: Double, tax: Double): Double {
    val discountedPrice = price * (1 - discount)
    return discountedPrice * (1 + tax)
}

val finalPrice = calculateFinalPrice(price = productPrice, tax = 0.08, discount = discountRate)
# Print the finalPrice rounded to two decimal places
# Your code here

Need a hint?

Use println("Final price: $" + "%.2f".format(finalPrice)) to print the formatted price.