Function to check if a list has no gaps

Question

I just want a function that returns true if all the elements of a List[Integer] follow each other, i.e.

noGaps(List(3,4,5)) // true
noGaps(List(4,3,5)) // false
noGaps(List(3,4,6)) // false

I have something that works but it's a bit verbose - what's the most elegant solution?

Answer 1

How about this?

def noGaps(xs: Seq[Int]) =
  xs.size < 2 || xs.sliding(2).forall { case Seq(x, y) => y == x + 1 }