Run-time problem

P44 - Attempt to remove a door from play

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.

Doors are part of the fixed geography of the model world, and are tied in to the map, so it is illegal to remove them from play. (Of course rules can be used to simulate the absence of a door, or to change its behaviour almost completely.)