I Problems with set method in computed properties

Hi Victor,

Getters and Setters are a bit weird and difficult to understand - they always confuse me! But that's quite easy!

The challenge wants you to create a getter for fahrenheit that uses the existing celsius value to calculate the conversion. The code provided at the start of the challenge does this. You just need to add the get bit to it:

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
             return (celsius * 1.8) + 32.0
         } 
         set {
              // do something
         }
    }    
}

That just leaves the setter to complete.

Essentially, the setter will change the value of celsius when the function is passed a value to fahrenheit. So, the calculation needs to be reversed, i.e. subtract 32 then divide by 1.8. The calculation is performed on the newValue which is the number passed into the function:

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
             return (celsius * 1.8) + 32.0
         } 
         set {
              celsius = (newValue - 32) / 1.8
         }
    }    
}

So, create am instance of Temperature and initialise it so celsius has a value of 32.

Typing temp.celsius will output 32. Looking at temp.fahrenheit will give you 89.59 using the get part of the function.

To use the set part, pass a value to fahrenheit like:

Enter temp.fahrenheit = 90 Then, temp.celsius will give you 15.55

So, you can influence each variable by changing the value of the other since they are mutually linked in that way.

Hope that helps,

Steve.