How to type check an object

One often needs to check if an object is of a particular type at runtime. With Java, we used an instance of a keyword; with Kotlin, it is the is keyword.

Getting ready

You need to install a preferred development environment that compiles and runs Kotlin. You can also use the command line for the purpose, for which you need Kotlin compiler installed along with JDK. I am using online IDE at https://try.kotlinlang.org/ to compile and run my Kotlin code for this recipe.

How to do it...

Let's see how to type check an object in these steps:

1. Let's try a very basic example, trying is with string and integer. In this example, we will type check a string and an integer:

fun main(args: Array<String>) {
    var a : Any = 1
    var b : Any = "1"
    if (a is String) {
        println("a = $a is String")
    }
    else {
        println("a = $a is not String")
    }
    if (b is String) {
        println("b = $b is String")
    }
    else {
        println("b = $b is not String...