2019-06-28-safe-max-min-for-empty-list-in-scala.md

title	date	tags
Safe Max/Min for Empty List in Scala	2019-06-28 19:30:00 +0900	scala

List (Seq) in Scala has max method but it is failed if the list is empty.

Try something like those:

val nums = List[Int].empty

val maxNum = nums.max // booom! you are dead

val maybeMaxNumA = nums.headOption(_ => nums.max) // yeah!
val maybeMaxNumB = nums.reduceOption(_ max _) // yeah!

You know, it works for min too.