Shorthand to Init a Scala Enumeration ValueSet with one Value

So I have a some Scala Enumeration object:

object KnotType extends Enumeration {
        type KnotType = Value
    val STOPPER, HITCH, ENDLOOP, MIDLOOP, ADJUSTABLELOOP, BEND, BINDING = Value
  }
  import KnotType._

  object AnotherType extends Enumeration {
        ...      }
  import AnotherType ._

I want to initialize a new ValueSet instance with one Value present only. In the shortest of shorthands:

val eKnots = STOPPER + HITCH
eKnot: KnotType.ValueSet = KnotType.ValueSet(STOPPER , HITCH)

Works a charm. However, to create a ValueSet from one value I have to be more explicit: (especially as there are more than on enum object classes)

Creating a enumeration from one value produces a Value (as expected) but is not what I'm after (a ValueSet):

val eKnot = STOPPER
eKnot: KnotType.Value = STOPPER

A conventional way would be:

val eKnot =  KnotType.ValueSet(STOPPER)
eKnot: KnotType.ValueSet = KnotType.ValueSet(STOPPER)

an inelegant way:

val eKnot = STOPPER + STOPPER
eKnot: KnotType.ValueSet = KnotType.ValueSet(STOPPER)

a long winded way - works fine but I'm after succinctness

val eKnot = KnotType.ValueSet.empty + STOPPER
eKnot: KnotType.ValueSet = KnotType.ValueSet(STOPPER)

Is there any other shorthand I could use? i.e val eKnot = STOPPER + /somethingsimple/