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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Stuck on Struct methods challenge task 3 of 4

Create a variable named item and assign it an instance of Expense (remember to use the initializer with the description parameter. Enter any description you like). On the next line assign the amount property a value of 100.

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

    init (description: String, amount: Double, item: String) {
        self.description = description
        self.item = Expense.description("car")
        self.amount = 100.0

    }

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

2 Answers

Stepan Ulyanin
Stepan Ulyanin
11,318 Points

Hi, you might want to create a variable and then create an instance of your struct and assign it to that variable, it is very easy to do:

var item = Expense(description: "Item description", amount: 10)

Make sure that you instantiate your struct outside of struct declaration, like shown below:

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

    init (description: String, amount: Double) {
        self.description = description
        self.amount = 100.0
    }

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

var item = Expense(description: "Item description", amount: 10)