safe Iterator.max

Is there a library that offers a function like Iterator.max开发者_Python百科, but that returns an Option[A] rather than an A to account for possibly-empty iterators? Alternately, is there a library that offers a class PosInf[A] or so that adjoins a positive infinity to A?

(Obviously either of these is mere gruntwork to do myself, but using a library is almost always preferable to duplicating code.)

scalaz: MA.maximum. Usage:

import scalaz._; import Scalaz._

List(1, 2, 3).maximum == Some(3)

List.empty[Int].maximum == None

the only problem is that this does not work with Iterators directly, so you would have to use a Stream instead (e.g. using Iterator.toStream)

List(1, 2, 3).iterator.toStream.maximum = Some(3)

I'm not aware of anything but this is simple:

def maxOpt[T: Numeric](i: Iterator[T]) = if (i.hasNext) Some(i.max) else None

Edit: Numeric is too strong a requirement, Ordering is enough:

def maxOpt[T: Ordering](i: Iterator[T]) = if (i.hasNext) Some(i.max) else None

And if you use isEmpty is should work on any subclass of TraversableOnce