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iOS Object-Oriented Swift Properties Getter and Setter Methods

I dont understand what I am doing wrong in with the getter and setter methods in Swift for iOS

The setter method for fahrenheit did not assign the right value to the celsius property. (Note: Celsius = (Fahrenheit-32)/1.8)

is my error, but in the set value I have that calculation set. I don't understand what is wrong here.

If anyone could provide a detailed explanation of why my code is wrong, and how to fix it, that would be great.

Thanks in advance.

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
        return celsius * 1.8 + 32.0

        set {
        return celsius = fahrenheit - 32 / 1.8


I figured out how to solve the problem, by changing fahrenheit to (nevValue)

but, I still dont understand why my last bit of code was invalid. Why was the challenge unable to understand taking farienheit and doing the calculations?

1 Answer

Stephen Hanson
Stephen Hanson
2,030 Points

I believe the reason you got an error, as you later discovered is that the setter method needs a newValue to work. In other words you are trying to set fahrenheit to a newValue when you call it. So by there not being a newValue in set, it did not know what set was trying to accomplish. Like if someone said to you "Paint these walls" and never provided you with a new color.