reversing the elements of list

[Harit Himanshu]

This is again in spirit of learning Scala and solving S99 problems.

The problem statement looks like  

P05 (*) Reverse a list.

Example:

scala> reverse(List(1, 1, 2, 3, 5, 8))
res0: List[Int] = List(8, 5, 3, 2, 1, 1)

and my solution looks like  

scala> def reverse[T](l:List[T], reversed:List[T]): Option[List[T]] = {

     |     l match {

     |       case Nil => if (reversed.nonEmpty) Some(reversed) else None

     |       case head::tail => reverse(tail, head::reversed)

     |     }

     |   }

reverse: [T](l: List[T], reversed: List[T])Option[List[T]]

scala> reverse(List(1,2,3), Nil)

res0: Option[List[Int]] = Some(List(3, 2, 1))

scala> reverse(List(), Nil)

res1: Option[List[Nothing]] = None

scala> reverse(List("one", "two", "three"), Nil)

res2: Option[List[String]] = Some(List(three, two, one))

scala> 

Questions

As you could see I have made use of two things, learned from my last post about "find nth element from list". My specific question is  

1. Is it a good idea to use Option most of the places where we see returning Null/None is possible?

Thanks

[Som Snytt]

The empty list reversed is still the empty list. Also, null is not possible; it's your job to ensure that.

scala> Nil.reverse
res2: List[Nothing] = List()

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[Harit Himanshu]

Got that Som. Thanks