FunctionChaining.kt

fun main() {
    val fun1: (Int) -> Int = { x -> x + 1 }
    val fun2: (String) -> String = { x -> x.reversed() }
    val fun3: (List<Int>) -> Int = { x -> x.sum() }
    val fun4: (Double) -> Double = { x -> x * x }

    val result1: (Int) -> Any = ::fun4::fun3::fun2::fun1
    val result2: (Int) -> Any = fun4::fun3::fun2::fun1

    val fun5: (Any) -> String = { x -> x.toString() }
    val fun6: (String) -> String = { x -> x.capitalize() }
    val fun7: (String) -> String = { x -> x.repeat(2) }
    val fun8: (String) -> String = { x -> x.substring(1) }

    val result3: (Int) -> String = fun8::fun7::fun6::fun5::result1
    val result4: (Int) -> String = ::fun8::fun7::fun6::fun5::result2

    println(result3(10)) // prints "100.0"
    println(result4(10)) // prints "100.0"
}

It is not a good practice....Just for fun!