ex22 - https://medium.com/@lu4nm3/bend-any-type-to-your-will-with-ad-hoc-polymorphism-4e6d326f1ff0

ex22_bend.scala

trait DairyFree[T] {
  def isDairyFree(item: T): Boolean
}

object DairyFree {
  implicit val baguetteDairyFree: DairyFree[Baguette] = new DairyFree[Baguette] {
    def isDairyFree(b: Baguette): Boolean = true
  }

  implicit val croissantDairyFree: DairyFree[Croissant] = new DairyFree[Croissant] {
    def isDairyFree(c: Croissant): Boolean = false
  }
}