Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

iOS Swift Enums and Structs Structs and their Methods Struct Methods

Don't know what to do


struct Expense {
    var description: String
    var amount: Double = 0.0

    func calculateTaxes() -> Double {
    var percentage: Double

    init (description: String) {
        self.description = description

    // add the calculateTaxes method here
    // it should accept only one parameter named 'percentage' of type Double


1 Answer

Hi there,

So you're required to add a function that's called calculateTaxes that takes a Double as a parameter called percentage and returns nothing:

func calculateTaxes(percentage: Double) {


That is the method skeleton for that. The next parts of the challenge ill develop it further from there.

Hope that helps!