Kotlin - Null Safety
What will be the output of this Kotlin code?
var text: String? = null println(text?.length ?: "No length")
What will be the output of this Kotlin code?
medium📝 Predict Output Q13 of 15
Step-by-Step Solution
Solution:
Step 1: Understand safe call and Elvis operator
text?.lengthsafely accesses length if text is not null; else returns null. The Elvis operator?:provides "No length" if left side is null.Step 2: Evaluate given code
Sincetextis null,text?.lengthis null, so the expression prints "No length".Final Answer:
No length -> Option CQuick Check:
Safe call + Elvis = fallback value [OK]
Quick Trick: Safe call ?. returns null safely; ?: provides default [OK]
Common Mistakes:
MISTAKES- Expecting NullPointerException on null safe call
- Thinking null?.length returns 0
- Ignoring Elvis operator fallback
Master "Null Safety" in Kotlin
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore Kotlin Quizzes