#9.1 Kotlin Lambdas and Higher Order Functions Part - 1. Kotlin Tutorial for Beginners

1. Introduction : Small Demo

Using Object Oriented Way : Interface

Using High level Functions

Using Lamdbas

 

2. Lambdas and High Level Fuctions in Detail

Explanation 

Demo

 

High Level Functions

Can accept Functions as parameters

Can return a Function

Or can do both

 

Lambdas

It is just a Function with no name

fun main(args: Array<String>){
    val program = Program()
    program.addTwoNumbers(3, 4)
}

class Program{
    fun addTwoNumbers(a: Int, b: Int){
        val sum = a + b
        println(sum)
    }
}

 

fun main(args: Array<String>){
    val program = Program()
    program.addTwoNumbers(3, 4)

    program.addTwoNumbers(2, 7, object : MyInterface{
        override fun execute(sum: Int) {
            println(sum)
        }
    })

    val test: String = "Hello"
    val myLambda: (Int) -> Unit = { s: Int -> println(s) } // lambda Expressiong [Function]

    program.addTwoNumbers(3,7) { s: Int -> println(s) }
}

class Program{
    fun addTwoNumbers(a: Int, b: Int, action: (Int) -> Unit){ // High level Function with lambda as Parameter
        val sum = a + b
        action(sum) // println(s)
    }

    fun addTwoNumbers(a: Int, b: Int, action:MyInterface){ // Using interface / Object Oriented Way
        val sum = a + b
        action.execute(sum)
    }

    fun addTwoNumbers(a: Int, b: Int){ // Simple way.. Just for better Understanding
        val sum = a + b
        println(sum) // body
    }
}


interface MyInterface{
    fun execute(sum: Int)
}

youtu.be/S0Vkldrh0SE