Question

Several combinations of methods on a collection can be expressed more succinctly in Scala. For example, xs.filter(f).headOption can be expressed as xs.find(f), and xs.map.filter can usually be better expressed through xs.collect.

I find myself writing xs.sortWith(f).head, and this feels to me like the sort of thing that could be expressed as a single method, “find me the least element in this collection, according to this sorting function”.

However, I can’t see any obvious methods on Seq or TraversableLike. Is there a single method that captures my intent, or is .sort.head the more elegant way to find the “least” element?

Answer 1

scala> val xs = List("hello", "bye", "hi")
xs: List[java.lang.String] = List(hello, bye, hi)

scala> xs.sortWith(_.length < _.length).head
res10: java.lang.String = hi

scala> xs.min(Ordering.fromLessThan[String](_ > _))
res11: java.lang.String = hi

scala> xs.min(Ordering.by((_: String).length))
res12: java.lang.String = hi

scala> xs.minBy(_.length)
res13: java.lang.String = hi