




Figure 2.4 KnowledgeWorks Objects Browser
The Objects Browser is for exploring the contents of the KnowledgeWorks object base. Start it by choosing 
KnowledgeWorks > 
Objects
. The system knows about the CLOS objects that make up the object base. One class of CLOS objects in this example is the 
node
 class so choose 
NODE
 from the 
Preset query/pattern
 drop-down. All the node objects in the object base will be displayed in the pane below. Click on one of these objects and the bottom pane will display the slots and slot values of the object.
To make the display clearer and allow input without explicit package qualifiers, change the package of the Objects Browser. Do this via 
Tools > Preferences...
. Edit the Package pane in the Objects Browser Preferences dialog so that it says 
KW-USER
 and press 
OK
.
Now change the 
Query
 field to read 
(node ?object animal ?a)
 and press 
Return
. The animals associated with each node are displayed. In this game there is a tree of questions with each node object representing a question. Some nodes have a 
nil
 value for the animal slot; these are the non-terminal nodes in the question tree. The program learns your new animals by adding new nodes to the tree.
Now type 
?a
 into the 
Pattern
 field (and press 
Return
). This displays only the animals. The values displayed in the topmost of the two panes is the 
Pattern
 field instantiated with every possible object that matches the 
Query
 field. However, if the 
Pattern
 field is empty then the value of the 
Query
 field is taken to be the pattern.
Change the 
Query
 field to read 
(and (node ?n animal ?a) (test ?a)) 
and press 
Return
.
Figure 2.5 Objects Browser matching animals
Only the non-
nil
 animals are displayed.