Pre-condition: the traveler is directly in the given room. This will attempt to remove the traveler from any nested rooms within the given room, but cannot perform travel between rooms not related by containment.

Note that the traveler is not necessarily the actor, because the actor could be in a vehicle.

This is a class, because it has to be instantiated with more parameters than just a single 'obj' passed by default when evaluating preconditions. In particular, we need to know the actor performing the travel, the connector being traversed, and the room we need to be directly in.

class TravelerDirectlyInRoom :   PreCondition