more elegant way to write if( list.nonEmpty) Some(list.max) else None?

scala functional-programming max scala-option
nairbv picture nairbv · Dec 9, 2013 · Viewed 8.1k times · Source

List.max returns the "largest" element of a list based on some ordering... But if the list is empty you'll get a java.lang.UnsupportedOperationException: empty.max exception. I don't really like littering code with if statements or matches or whatever. I want something like headOption for max, but I'm not seeing such a method. What's the most elegant way to get the equivalent of list.maxOption?

Answer

Rob Napier picture Rob Napier · Dec 9, 2013

You can convert a Try into an Option:

Try(empty.max).toOption

You can also use reduceOption (as given in scala - Min/max with Option[T] for possibly empty Seq?):

l.reduceOption(_ max _)

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