Dmitry Jemerov
Do you remember how children memorize the colors of the rainbow? "Richard Of York Gave Battle In Vain!" Imagine you need a function that gives you a mnemonic for each color (and you don't want to store this information in the enum itself). In Java you can use a switch statement for this. The corresponding Kotlin construct will be when. Like if, when is an expression that returns a value, so you can write a function with an expression body, returning the when expression directly.