gistfile1.scala

object cbfx2 {
    trait X[K, L]

    trait A[T] {
        def foo[L](i: L)(implicit a: X[T, L]) = null
    }

    class B[T] extends A[T]

    object B {
        implicit def foo[T, L]: X[T, L] = {println("B");null}
        implicit def foo2[T]: X[T, Int] = {println("B Int");null}
    }

    class C extends B[C]

    object C {
        implicit def foo[L]: X[C, String] = {println("C");null}
    }

    class K { def foo(implicit k: Int) = null }
    object K { implicit def foo = 0}

    def main(args: Array[String]) {
        import K._
        val k = new K
        k.foo
        val b = new B[B[Int]]
        b.foo("a")
        b.foo(3)

        val c = new C
        c.foo(3)
        c.foo("dd")
    }
}