P31 - Attempt to use a property of nothing

Most problems are detected when Inform translates the source text, but this is one of the exceptions, a "run-time problem" which emerges only during play.

The special value nothing is used to mean no object at all, and sometimes appears where an object might be expected if it was impossible to find a genuine object, or no genuine object was specified.

Nothing is not an object in its own right, and so it makes no sense to look at its properties.