Experimenting with how Scala handles multiple implicit conversions in scope when those conversions apply to child types.

implicit-hierarchy.scala

scala> class A { val prop = "a" }
scala> class B extends A { override val prop = "b" }
scala> class C extends B
scala> implicit class Foo(a: A) { def value = a.prop }
scala> implicit class Bar(b: B) { def value = b.prop }
scala> val c = new C
scala> c.value
res0: String = b


scala> class A { val prop = "a" }
scala> class B extends A { override val prop = "b" }
scala> class C extends B
scala> implicit class Foo(a: A) { def value = a.prop }
scala> implicit class Bar(b: B) { def value = b.prop }
scala> val c = new C
scala> c.value
res0: String = b