Using the 'mapNotNull' Function for Transforming Collections with Null Filtering

The 'mapNotNull' function is a powerful tool in Kotlin that allows you to transform a collection while simultaneously filtering out any null results. This is particularly useful when dealing with collections that may contain null elements, ensuring that your resulting collection only contains valid, non-null values. By using this function, you can achieve cleaner and more concise code without having to explicitly check for nulls.

data class User(val id: Int, val name: String?)

fun main() {
    val users = listOf(User(1, "Alice"), User(2, null), User(3, "Bob"))

    val userNames = users.mapNotNull { it.name }

    println(userNames) // Output: [Alice, Bob]
}