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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Nuttakit Luengwitayakorn
Nuttakit Luengwitayakorn
1,626 Points
Posted by Nuttakit Luengwitayakorn
Nuttakit Luengwitayakorn
1,626 Points

My code doesn't work

My code doesn't work please help

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

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

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

}

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

in your function body you are returning a double, however your function does not have its return type declared. add the return type

the swift eBook states:

You indicate the function’s return type with the return arrow -> (a hyphen followed by a right angle bracket), which is followed by the name of the type to return.

so to return a double you would use

func calculateTaxes ( percentage : Double ) -> Double {
        return self.amount * (percentage/100)
    }
Jason Hernandez Berland
Jason Hernandez Berland
1,575 Points

Thanks Stone Preston . Totally confused. Challenge says: "add a method named calculateTaxes which accepts a parameter named 'percentage' of type Double and does not return anything"

So why do you add this line if it says to not return anything? 

return self.amount * (percentage/100)

And why do you have to declare the type Double twice in the first line?