Kotlin Academy · Lesson

Safe Calls and Elvis

?. and ?: operators.

Working with Nullables Cleanly

Writing if (x != null) everywhere gets verbose. Kotlin offers two concise operators for nullable values:

The safe call ?. calls a method or reads a property only if the value is not null. Otherwise the whole expression evaluates to null.

No crash, no explicit check.

fun main() {
    val name: String? = "Kotlin"
    println(name?.length)
}