How would I obtain the minimum gap between List elements?

Question

For example suppose I have a sorted list

val sorted = List(1, 5, 15, 37, 39, 42, 50)

The smallest gap is (39-37)=2. How would I obtain this result? I have been looking at foldLeft I get the feeling it is similar to what I need but not quite the right thing

Answer 1

val sorted = List(1, 5, 15, 37, 39, 42, 50)

sorted match { 
  case Nil => None
  case List(a) => None
  case l => Some(l.sliding(2).map{case Seq(a, b) => math.abs(a - b)}.min)
}
// res1: Option[Int] = Some(2)

sliding returns an iterator, so that should only traverse the list once.

If you are interested to find which two elements have the smallest gap, you can also use minBy. So here is another variation, just for fun.

sorted.view.zip(sorted.tail).minBy(t => math.abs(t._1 - t._2))
// res4: (Int, Int) = (37,39)