An example of how tail recursion avoids stack overflow errors

TailRecursion.scala

// based on https://github.com/matt-martin/fpinscala/blob/05cd5a2b288677ebc67d258fcfb9c06b63052314/exercises/src/main/scala/fpinscala/datastructures/List.scala#L11
def sumNonTailRecursive(ints: List[Int]): Int = ints match {
  case Nil => 0
  case x :: xs => x + sumNonTailRecursive(xs)
}

@annotation.tailrec
def sumTailRecursiveHelper(ints: List[Int], sumSoFar: Int): Int = ints match {
  case Nil => sumSoFar
  case x :: xs => sumTailRecursiveHelper(xs, sumSoFar + x)
}

def sumTailRecursive(ints: List[Int]): Int = sumTailRecursiveHelper(ints, 0);

// works
sumTailRecursive(List((1 to 10000).toSeq:_*))

// doesn't work
sumNonTailRecursive(List((1 to 10000).toSeq:_*))