object +: {
  import collection.LinearSeqLike
  def unapply[T, Coll <: LinearSeqLike[T, Coll]](t : Coll with LinearSeqLike[T, Coll]) : Option[(T, Coll)] = {
    if (t.isEmpty) None
    else Some(t.head -> t.tail) // TODO - Try to remove cast.
  }
}

qbin/scala -classpath /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home/jre/lib/jfxrt.jar
Welcome to Scala version 2.11.0-20130330-204812-2a6e83a85e (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_37).

scala> type CircleBuilderF = ({type CB <: CircleBuilder[CB]; type CB1 = CB with CircleBuilder[CB]})#CB1
defined type alias CircleBuilderF

scala> def newCircleBuilder: CircleBuilderF = CircleBuilder.create.asInstanceOf[CircleBuilderF]
newCircleBuilder: CircleBuilderF

scala> newCircleBuilder.centerX(0).centerX(0).build()
res28: javafx.scene.shape.Circle = Circle@38b9a306

scala> CircleBuilder.create.centerX(0).centerX(0).build()
<console>:14: error: value centerX is not a member of ?0
              CircleBuilder.create.centerX(0).centerX(0).build()
                                              ^

scala> trait FBounded[M[_]] { type F <: M[F]; type Apply = F with M[F] }
warning: there were 1 feature warning(s); re-run with -feature for details
defined trait FBounded

scala> CircleBuilder.create.asInstanceOf[FBounded[CircleBuilder]#Apply].centerX(0).centerX(0).build()
<console>:15: error: kinds of the type arguments (javafx.scene.shape.CircleBuilder) do not conform to the expected kinds of the type parameters (type M) in trait FBounded.
javafx.scene.shape.CircleBuilder's type parameters do not match type M's expected parameters:
type B's bounds <: javafx.scene.shape.CircleBuilder[B] are stricter than type _'s declared bounds >: Nothing <: Any
              CircleBuilder.create.asInstanceOf[FBounded[CircleBuilder]#Apply].centerX(0).centerX(0).build()

scala> implicit class RichFBoundBuilder[B[X <: B[X]]](val _builder: B[_]) {
  type B1 = X forSome { type X <: B[X] }
  def asScala: B1 = _builder.asInstanceOf[B1]
}
warning: there were 2 feature warning(s); re-run with -feature for details
defined class RichFBoundBuilder

scala> import javafx.scene.shape._
import javafx.scene.shape._

scala> CircleBuilder.create.asScala.centerX(0).centerX(0).build()
res0: javafx.scene.shape.Circle = Circle@6c60efe7