Kotlin Programming: The Big Nerd Ranch Guide, First Edition

Function Type as Return Type

Like any other type, the function type is also a valid return type, meaning you can define a function that returns a function.

In SimVillage, define a configureGreetingFunction function that configures the arguments for the lambda held by the greetingFunction variable and generates and then returns the lambda, ready for use:

Listing 5.13  Adding the configureGreetingFunction function (SimVillage.kt)

fun main(args: Array<String>) {
    runSimulation("Guyal", ::printContructionCost) { playerName, numBuildings ->
        val currentYear = 2018
        println("Adding $numBuildings houses")
        "Welcome to SimVillage, $playerName! (copyright $currentYear)"
    }
    runSimulation()
}

inline fun runSimulation(playerName: String,
                        costPrinter: ...