Higher-Order Functions

HigherOrderFunctions.kt

fun main() {

    val sumResult = calculate(4, 5, ::sum)                          //sumResult 9,
    val mulResult = calculate(4, 5) { a, b -> a * b }               // mulResult 20
    println("sumResult $sumResult, mulResult $mulResult")

}

fun calculate(x: Int, y: Int, operation: (Int, Int) -> Int): Int {
    return operation(x, y)
}

fun sum(x: Int, y: Int) = x + y