Thank you so much for answering, I will try adding the sampleData inside the struct instead. But it's quite funny since this is what the code from the tutorial. import Foundation struct DailyScrum { var title: String var attendees: [String] var lengthInMinutes: Int var theme: Theme } extension DailyScrum { static let sampleData: [DailyScrum] = [ DailyScrum(title: "Design", attendees: ["Cathy", "Daisy", "Simon", "Jonathan"], lengthInMinutes: 10, theme: .yellow), DailyScrum(title: "App Dev", attendees: ["Katie", "Gray", "Euna", "Luis", "Darla"], lengthInMinutes: 5, theme: .orange), DailyScrum(title: "Web Dev", attendees: ["Chella", "Chris", "Christina", "Eden", "Karla", "Lindsey", "Aga", "Chad", "Jenn", "Sarah"], lengthInMinutes: 5, theme: .poppy) ] }