Scala Quiz - 2

Question 1

Question

What's a higher order function ?

Answer

A function that takes another function as argument
A function that returns a function
Any of the above two
None of above

Question 2

Question

Which of the following is most adapted for parallel processing ?

Answer

Akka Actors
Scala Futures
Scala Options
Scala Either

Question 3

Question

val result = for { x <- Future(20) y <- Future(10) if y > 10 } yield x + y what's the value of result ?

Answer

Success(30)
30
Failure

Question 4

Question

Which one is FALSE about an actor akka ?

Answer

Can communicate with an actor using tell function
Can communicate with an actor using ask pattern
Messages can be passed to an actor using ActorRef handle of that actor
Messages can be passed to an actor using Actor instance of that actor

Question 5

Question

A monad is a functor which also has a flatMap ?

Answer

True
False

Question 6

Question

What's NOT true about a type class in scala ?

Answer

It enables ad hoc polymorphism
It uses implicts, implicitly and bound context syntax
Addition of a new functionality in type class can be done without any changes to the original code
Type class is an abstract class

Question 7

Question

SBT performs incremental recompilations ?

Answer

True
False

Question 8

Question

val mySeq = Seq("Hello world", "Hello how are you", "Are you well", "Hello guys") val result = mySeq.flatMap(_.split(" ")).map(_.length).filter(v => v < 4).reduce(_ + _) What's result ?

Answer

28
43
15
None of the above

Question 9

Question

trait F[-A] { } What does -A represent ?

Answer

Covariant type parameter
Contravariant type parameter
Lower bound
Upper bound

Question 10

Question

Choose right responses for a partial function (multiple responses possible)

Answer

A PartialFunction must provide a method isDefinedAt
A PartialFunction must provide a method apply
Can be lifted to a normal function with return type wrapped in an option
Akka actor's receive method is not an example of partial function

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Scala Quiz - 2

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Resource summary

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

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	Created by himanshu arora over 6 years ago