1.
What is a data class in Kotlin?
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Xamarin Kotlin interview questions.
Only challenges
- 2.
How to initialize an array in Kotlin with values?
Answer:
- 3.
What is the idiomatic way to remove duplicate strings from array?
Answer:
- 4.
Where should I use var and where val?
Answer:
- 5.
What is basic difference between fold and reduce in Kotlin? When to use which?
Answer:
- 6.
What is a primary constructor in Kotlin?
Answer:
- 7.
How to correctly concatenate a String in Kotlin?
Answer:
- 8.
What is the difference between var and val in Kotlin?
Answer:
- 9.
How to create singleton in Kotlin?
Answer:
- 10.
What is the difference between suspending vs. blocking?
Answer:
- 11.
val mutableList vs var immutableList. When to use which in Kotlin?
Answer:
- 12.
What is Lateinit in Kotlin and when would you use it?
Answer:
- 13.
How are extensions resolved in Kotlin and what doest it mean?
Answer:
- 14.
May you briefly compare Kotlin vs Java?
Answer:
- 15.
What is the difference between const and val?
Answer:
- 16.
What are some disadvantages of Kotlin?
Answer:
- 17.
Why would you use apply in Kotlin?
Answer:
- 18.
Explain the Null safety in Kotlin
Answer:
- 19.
What is the idiomatic way to deal with nullable values, referencing or converting them?
Answer:
- 20.
What is the equivalent of Java static methods in Kotlin?
Answer:
- 21.
Explain advantages of when vs switch in Kotlin
Answer:
- 22.
May you use IntArray and an Array
is in Kotlin interchangeably? Answer:
- 23.
What is suspending function in Kotlin?
Answer:
- 24.
How would you create a singleton with parameter in Kotlin?
Answer:
- 25.
When would you use Elvis operator in Kotlin?
Answer:
- 26.
What is the Kotlin double-bang (!!) operator?
Answer:
- 27.
What are scope functions in Kotlin?
Answer:
- 28.
What are coroutines in Kotlin?
Answer:
- 29.
What are the advantages of Kotlin over Java?
Answer:
- 30.
What is a difference between a class and object in Kotlin?
Answer:
- 31.
What is the purpose of Unit-returning in functions? Why is VALUE there? What is this VALUE?
Answer:
- 32.
When to use lateinit over lazy initialization in Kotlin?
Answer:
- 33.
Explain lazy initialization in Kotlin
Answer:
- 34.
What is the difference between List and Array types?
Answer:
- 35.
What is a purpose of Companion Objects in Kotlin?
Answer:
- 36.
How is it recommended to create constants in Kotlin?
Answer:
- 37.
What is the difference between open and public in Kotlin?
Answer:
- 38.
Explain what is wrong with that code?
Answer:
- 39.
How would you refactor this code using apply?
Answer:
- 40.
How to convert List to Map in Kotlin?
Answer:
- 41.
What will be result of the following code execution?
Answer:
- 42.
Rewrite this code in Kotlin
Answer:
- 43.
How can I create static method for enum in Kotiln?
Answer:
- 44.
What is Kotlin backing field is used for?
Answer:
- 45.
Explain the difference between Inline classes vs type aliases
Answer:
- 46.
Why is there no static keyword in Kotlin?
Answer:
- 47.
What are Object expressions in Kotlin and when to use them?
Answer:
- 48.
What is Coroutine Scope and how is that different from Coroutine Context?
Answer:
- 49.
Provide a real use case when inline classes may be useful
Answer:
- 50.
What is the difference between launch/join and async/await in Kotlin coroutines?
Answer:
- 51.
What is The Billion Dollar Mistake?
Answer:
- 52.
How does the reified keyword in Kotlin work?
Answer:
- 53.
How Kotlin coroutines are better than RxKotlin/RxJava?
Answer:
- 54.
What is the difference between Java field and Kotlin property?
Answer:
- 55.
When to use and do not use an inline function in Kotlin?
Answer:
- 56.
What is a motivation to make classes final by default in Kotlin? Do you agree with that decision?
Answer:
- 57.
Why do we use “companion object” as a kind of replacement for Java static fields in Kotlin?
Answer:
- 58.
What is SAM Conversion in Kotlin?
Answer:
- 59.
What is the difference between * and Any in Kotlin generics?
Answer:
- 60.
Explain the difference between lateinit and lazy in details
Answer:
- 61.
What is inline class in Kotlin and when do we need one? Provide an example.
Answer:
- 62.
How to create an instance of anonymous class of abstract class in Kotlin?
Answer:
- 63.
How to create empty constructor for data class in Kotlin?
Answer:
- 64.
Rewrite this code using run extension function
Answer:
- 65.
How would you override default getter for Kotlin data class?
Answer:
- 66.
What's wrong with that code?
Answer:
- 67.
How to implement Builder pattern in Kotlin?
Answer:
- 68.
Imagine you moving your code from Java to Kotlin. How would you rewrite this code in Kotlin?
Answer:
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