Const
Every label type a promoted attribute definition may declare, in the order they are offered to the user. This is the runtime source of truth: LabelType is derived from it, so a new type cannot be added to the union without parse also accepting it.
Every label type a promoted attribute definition may declare, in the order they are offered to the user. This is the runtime source of truth: LabelType is derived from it, so a new type cannot be added to the union without parse also accepting it.