Stream.Custom.Ordering

trait Ordering[A]

This trait can be mixed with existing Ordering inplementations to provide more efficient ways for Streams to calculate min,max, and range.

Apparently primitive based numeral data elements use it a lot

Source
Ordering.scala
class java.lang.Object
trait scala.Matchable
class Any

Def

def maxOpt(s: Stream[A]): Opt[A]
def minOpt(s: Stream[A]): Opt[A]
def rangeOpt(s: Stream[A]): Opt[Range[A]]