8.6.5. Future extensions: currentobjects, currentsubjects
It seems possible to add yet more standard variables. A do expression might be in scope of both a current subject and a current object, but the state transition it is contained in will be just one of them (or, of course, it will be on a context type transition).
So, for example, an expression in a do in subject state cannot refer to the current object. Yet, as we can compute the current context, we can compute the object from it.
However, if the object role is relational, there may be more than one instance available. This causes a curious phenomenon: when an expression occurs in the body of a do in object state, it can refer to one object as origin, and to all objects as currentobjects.