Sofu.Sofu.Map file = SofuReader.LoadFile("file.sofu");
            file.SetAttribute("Foo",new Sofu.Sofu.Reference("someref",new Sofu.Sofu.Value("Bar")));
            foreach (KeyValuePair<string,Sofu.SofuObject> entry in file) {
                if (entry.Value.IsDefined()) {
                    Console.Out.Write(entry.Key.ToString());
                    Console.Out.Write(" is defined"); //Write at least "Foo is defined"
                }
            }