dep-types.scala

scala> trait Foo[T] {
     | type A
     | def woozle(a: T): A
     | }
defined trait Foo

scala> implicit val bar = new Foo[Int] {
     | type A = String
     | def woozle(a: Int): A = s"hamish has had $a cakes today"
     | }
bar: Foo[Int]{type A = String} = $anon$1@5af864a7

scala> implicit val baz = new Foo[String] {
     | type A = Int
     | def woozle(a: String): A = 0
     | }
baz: Foo[String]{type A = Int} = $anon$1@833835c

scala> def thingy[T](c: T)(implicit F: Foo[T]): F.A = F.woozle(c)
thingy: [T](c: T)(implicit F: Foo[T])F.A

scala> thingy(1)
res3: bar.A = hamish has had 1 cakes today

scala> thingy("hey")
res4: baz.A = 0