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iOS Intermediate Swift 2 Properties Type and Computed Properties

Li Lin
PLUS
Li Lin
Courses Plus Student 2,654 Points

If we don't specify a constant to bind the value in a computed property's setter, it is automatically bound to ____?

What is the answer for the quiz question?

"If we don't specify a constant to bind the value in a computed property's setter, it is automatically bound to variable named ____"

Thanks a lot!

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points

Hello :

Your answer is newValue.

This means, that you can name your setter to anything you like, but if you don't, it will automatically adopt it's default name "newValue".

For example :

var celsius: Double = 0

var fahrenheit: Double {
get {
    return (celsius * 1.8) + 32
} set { // Will use "newValue"
    (newValue - 32 ) / 1.8
    }
}

fahrenheit // prints 32

But if you add a name to the setter

var celsius: Double = 0

var fahrenheit: Double {
get {
    return (celsius * 1.8) + 32
} set myValue { // Will use "myValue" instead
    (myValue - 32 ) / 1.8
    }
}

fahrenheit // prints 32

Good luck.