Course Name:- Scala 101
Scala 101 Cognitive Class Final Exam Answers:-
Question 1. A higher-order function allows us to:
- Be more declarative and not write “how” to perform work
- Pass a function to a data container
- Compose multiple transformations within a context
- Remain immutable
- All of the above
Question 2. How does Scala determine types when they are not specified?
- Implicit typing
- Type compliance
- Type inference
- Dynamic typing
- Type coercion
Question 3. What are valid members in objects?
- Class factories
- None of the above
- All of the above
- Utility methods
- Constant definitions
Question 4. What do default values and named parameters help you avoid in your code?
- Method overriding
- Singleton instances
- Method overloading
- Type declarations
- None of the above
Question 5. What does the Scala REPL stand for?
- Read, Evaluate and Print Loop
- React, Evaluate and Print Loop
- React, Emulate and Print Loop
- Read, Emulate and Print Loop
- Read, Emulate and Process Loop
Question 6. What is not true about class parameters?
- They are automatically immutable
- You must specify their type
- They live for the life of the class
- They are visible to outsiders
- None are true
Question 7. What is the maximum number of elements in a tuple?
- 22
- 11
- 2
- 32
- 12
Question 8. What keyword does not exist in Scala?
- new
- val
- implicit
- for
- static
Question 9. Which accessibility rule is not true?
- private is visible within a package
- private does not allow outsiders to see a field
- public does allow outsiders to see a field
- public is not visible outside of a package
- All are true
Question 10. Which are valid collection types in the Scala standard library?
- Vector
- ByteSet
- HashSeq
- LinkedSet
- All are valid
Question 11. Which collection type has effectively constant time performance characteristics for all operations?
- Vector
- Stream
- HashMap
- List
- Array
Question 12. Which combination is thread-safe?
- val and mutable data
- var and mutable data
- var and immutable data
- val and immutable data
- None are thread-safe
Question 13. Which feature is not synthetically generated for case classes?
- Companion object
- clone method
- equals method
- apply and unapply
- All are generated
Question 14. Which is not a valid data container type in Scala?
- Try
- Future
- Companion object
- Option
- None of the above
Question 15. Which is the top-most collection type in the Scala collections hierarchy?
- Interpretable
- Transformable
- Iterable
- Traversable
- Observable
Question 16. Which keyword constructs a new instance of a class?
- make
- new
- instance
- create
- None of the above
Question 17. Which language cannot be compiled to run on the JVM?
- JRuby
- C
- Clojure
- Scala
- Java
Question 18. Which language features are true about Scala?
- Statically typed
- Multi-Platform
- Object-Oriented
- Functional
- All of the above
Question 19. Which statement is not true about infix notation?
- You can omit parentheses
- You can use it when you pass multiple parameters
- You can use it with symbolic method names (+, -, etc)
- All are true
- None are true
Quesstion 20. Which statement is true about field and method evaluation?
- Fields are evaluated at the call site, methods are evaluated at construction
- Fields are evaluated at construction, methods are evaluated at the call site
- Fields and methods are evaluated at construction
- Fields and methods are evaluated at the call site
- None of the above