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//Name: (only comma separated data types) -> return data type
ft: (Int, Int) -> Int

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ft(1, 2) 
//OR
ft.invoke(1, 2)

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fun doSomething(a: Int, b: Int, ft: (Int, Int) -> Int): String {
    val result = ft(a, b) //OR ft.invoke(a, b)
    return “doSomething: ” + result
}

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//Calling a higher order function 
println(doSomething(1, 2, {x: Int, y: Int -> x + y})) 
//prints: doSomething: 3

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//nameOfTheLambda: function type = { comma separated pascal parameters -> business logic }
val lambda: (Int, Int): Int = { x: Int, y: Int -> x + y }

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//Normal function
fun increment (x: Int): Int {
  return x + 1
}

//The equivalent lambda expression for above function
val lambda: (Int): Int = { x -> x + 1 }

//The equivalent short lambda expression for above single parameter lambda
val lambda: (Int): Int = { it + 1 }

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println(lambda(1,2)) //prints: 3

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println(doSomething(1, 2, lambda)) //prints: doSomething: 3

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//fun(comma separated pascal parameters) = business logic
fun(x: Int, y: Int) = x + y

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//Storing an anonymous function in a variable
val anonymousFunction: (Int, Int): Int = fun(x: Int, y: Int) = x + y