Scala: How can I explicitly compare two Options?
implicit, scala, scala-option
Solution
You can just ask for the ordering implicit directly:
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scala> implicitly[Ordering[Option[Int]]]
res0: Ordering[Option[Int]] = scala.math.Ordering$$anon$3@501a9177
scala> res0.compare(Some(1), Some(3))
res1: Int = -1
Problem
If I have two Options such as ``` val a = Option(2) val b = Option(1) ``` I can write ``` List(a,b).sorted ``` and it sorts correctly by inserting an implicit Ordering. How can I get a reference to this Ordering so I can call `compare(a,b)` and get the result? I'd like the equivalent of ``` val comparison = a.compare(b) ``` except without having a and b be instances of Ordered.