Functional Kotlin

Properties

As discussed previously, classes can have a state. In Kotlin, a class's state is represented by properties. Let's have a look at the blueberry cupcake example:

class BlueberryCupcake {  var flavour = "Blueberry"}

The  BlueberryCupcake class has an has-a property flavour of type String.

Of course, we can have instances of the BlueberryCupcake class:

fun main(args: Array<String>) {    val myCupcake = BlueberryCupcake()    println("My cupcake has ${myCupcake.flavour}")}

Now, because we declare the flavour property as a variable, its internal value can be changed at runtime:

fun main(args: Array<String>) {    val myCupcake = BlueberryCupcake()    myCupcake.flavour = "Almond"    println("My cupcake has ${myCupcake.flavour}")}

That is impossible in ...