2.4.2 Objects Browser

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 Works > 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.

KnowledgeWorks and Prolog User Guide (Unix version) - 29 Feb 2008