Kotlin · question
Question 5 of 41
Explain Kotlin's null safety features
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Kotlin's type system distinguishes between nullable and non-nullable types, eliminating null pointer exceptions at compile time.
var name: String = "John" // Non-nullable
// name = null // Compilation error
var nullableName: String? = "John" // Nullable
nullableName = null // OK
// Safe call operator
val length = nullableName?.length
// Elvis operator
val displayName = nullableName ?: "Unknown"
// Not-null assertion (use carefully)
val definiteLength = nullableName!!.length
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