Listing 2 (thing.cpp)

#include "thing.hpp"

//  Thing.cpp -- 2/27/91  --  Michael Kelly - Author
//
//  See Thing.hpp for definition of class Thing
//
//  Assigning one Thing to another is a "shallow copy"
//  so TheNullThing is used to "zero out" temporary
//  variables that are in the Thing domain. This
//  way two different destructors do not try to
//  release the same dynamic memory.
//
const Thing TheNullThing;

// End of File