Question

I’m using some java.util.Date (which implements java.lang.Comparable) and would like to be able to use it nicely, e.g. use < and >= instead of “compareTo(other) == 1”. Is there a nice way to just easily mix in something like scala.math.Ordered without a lot of boiler plate?

Answer 1

In the Ordering companion object there is an implicit conversion from Comparable[A] to Ordering[A]. So you can do this:

import java.util.Date

val dateOrdering = implicitly[Ordering[Date]]
import dateOrdering._

val now = new Date
val then = new Date(now.getTime + 1000L)

println(now < then) // true