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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Ling Cheng
Ling Cheng
3,168 Points
Posted by Ling Cheng
Ling Cheng
3,168 Points

Isn't that a Double? why it said it's not a Double?

Isn't that a Double? why it said it's not a Double?

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(description: "myke")
item.amount = 100
var taxes = item.calculateTaxes(7.5)

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Hello Ling:

Your code looks perfect, I’m not sure why is not passing your challenge. I just finished the challenge myself to see what is wrong but can’t seem to find a difference between mine and yours, other than a few spaces that should not affect anything. Anyways here is my code if you want to check yours and see if you can fix it. 

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

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

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

var item = Expense(description: "Nike")
item.amount = 100
var taxes = item.calculateTaxes(7.5)
Ling Cheng
Ling Cheng
3,168 Points
Ling Cheng
Ling Cheng
3,168 Points

I've found that out, my Double is an optional that makes me couldn't get through this.

Thnaks!!