class Test { class Foo1 { def must(x: scala.xml.Elem) = () } class Foo2 { def must(x: Int) = () } implicit def toFoo1(s: scala.xml.Elem) = new Foo1() implicit def toFoo2(s: scala.xml.Elem) = new Foo2() def is: Unit = { ({"a"}).must({"b"}) } }