A very simple version of the NameMatchPredicate that checks whether
the object's toString() description matches the specified string,
by looking to see if the match is a substring of the description.
This class implements a "singleton container" - everyone who has
one is sharing the same reference, so it's effectively a single
extra-dimensional space that can be used to transfer items across
great distances.
Sets the default terrain for the map: the terrain that
will be returned if a query is made on a location where no
terrain type has been set explicitly using setTerrain().
This method is here for the sake of completeness, but it's
not recommended that objects change the original text of a
command, as other objects may rely on it.
The odds (of 1000) that a given corridor ends in a "phase wall"- a
barrier that appears and disappears at random but which otherwise
appears to be a normal wall.
Sets or clears event flag indicating that the command specified
a partial amount of the object (applies only if the object has
the "groupable" property).
Convenience method; when constructing an event, a Command
should set the verb; otherwise it'll have to be deduced from
the command text, and the guess could be incorrect.