The user may define subclasses of this class.
If A is onRight of B, then A is the primary object, B is the related object and onRight comes from NeighbourLocation. onRight or onLeft are in the context of a third object, a way (a route or line) to which A and B are adjacent or near (in the neighbourhood of). This relationship could be used with street addresses, for example, in which the way is the street. The way is specified by the object identifier of the relevant geographic object.