Kotlin Programming Cookbook

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You can also create your own function by extending Kotlin's code. For example, creating a method, as follows:

inline fun <reified inside> array2d(sizeOuter: Int, sizeInner: Int, noinline innerInit: (Int)->inside): Array<Array<inside>>       = Array(sizeOuter) { Array<inside>(sizeInner, innerInit) }

This can enable you to create a 2D array quite easily, just by doing the following:

array2d(10,10,{0})

You can also create a list of lists in a similar fashion. Here's an example of a list of lists:

fun main(args: Array<String>) {    val a= listOf(listOf(1,2,3), listOf(4,5,6), listOf(7,8,9))    a.forEach {        print(" ${it} ")    }}

This is its output:

[1, 2, 3] [4, 5, 6] [7, 8, 9]