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iOS

Posted by kaitlanlang
kaitlanlang
3,042 Points

Add a method to the Expense struct that will calculate taxes based on a percentage and add it to the stored property am

this is a beginners course Amit, you have many smart people doing it. but It is very getting tiring watching material over and over and only having real vague ideas how to proceed.Applying a new concept is only useful when the concept is clear after video. Referencing the apple swift book is a great idea to solidify a taught concept, but having to go there to learn it completely because video was not clear at all is poor form. Its not just the concept either, sometimes you may understand a concept but question presentation leaves you scratch your head what is being asked. Anyway rant over, question with my working I have no idea about

Add a method to the Expense struct that will calculate taxes based on a percentage and add it to the stored property amount. In this task, add a method named calculateTaxes which accepts a parameter named 'percentage' of type double and does not return anything. (In the next task we will add the calculations to the method).

below I am returning nothing as requested by question and it accepts one parameter percentage. please explain the err of my ways comprehensively amit.

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


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



    func calculateTaxes(percentage: Double) -> {
        return

    }

}
Michael Cobb
Michael Cobb
2,166 Points

This one was pretty difficult!

Give this a try...

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

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

    }

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

}

2 Answers

kaitlanlang
kaitlanlang
3,042 Points

Hi Michael, thanks for the reply. I went and read the apple swift book on functions and found a spot in book with 'no' return types, I entered the to follow code and it accepted it as correct. Since the question only wanted us to do part of task more to be done in other questions, essentially my understanding of what was being asked was to leave a placeholder function to be worked on later. So the following felt counter intuitive. My light bulb moment was realising that as nothing is being returned this symbol -> is not needed.

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

    init (description: String) {
        self.description = description
    }
 func calculateTaxes(percentage: Double)  {

    }

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

}
Michael Cobb
Michael Cobb
2,166 Points
Michael Cobb
Michael Cobb
2,166 Points

Awesome job doing the research! I didn't necessarily understand it as well as you explained.

Thanks!

kaitlanlang
kaitlanlang
3,042 Points

Thanks Michael, your comment has made my day :)