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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Posted by Jack Harland
Jack Harland
879 Points

Why wont this work?! Structs + Methods please help! :(

Hello All :)

I get this error code every time: swift_lint.swift:18:22: error: cannot convert the expression's type '(percentage: FloatLiteralConvertible)' to type '(Double) -> Double'

Why is it trying to convert it? What have i done wrong?

Thank you Harland

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

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

    }
func calculateTaxes(percentage: Double) -> Double {
return (self.amount*(percentage/100)) } 
    // add the calculateTaxes method here
    // it should accept only one parameter named 'percentage' of type Double

}

  var item = Expense.calculateTaxes(percentage: 7.5) 
  var taxes = item 
        item.amount = 100

1 Answer

miguelcastro2
miguelcastro2
Courses Plus Student 6,573 Points

You to need first create an instance of Expense strut before you can call a method:

// Create instance
var item = Expense(description: "Travel Expense")

// Call method
var taxes = item.calculateTaxes(7.5)