How it works...

We have used a range expression together with the in operator in order to define a condition for the if statement. The condition statement is natural to read and concise. In contrast, an equivalent classic implementation would look like this:

val randomInt = Random(20).nextInt()
if (randomInt >= 0 && randomInt <= 10) {
    print("$randomInt belongs to <0, 10> range")
} else {
    print("$randomInt doesn't belong to <0, 10> range")
}

No doubt, the declarative approach using the range and in operator is cleaner and easier to read, compared to classic, imperative-style condition statements.