Before we are able to edit a Telos object, we have to load its frame representation in to the Telos Editor field first. For loading a Telos object to the Editor field, we choose the Telos Editor Button from either the Display Queries oder Display Instances Browsing facilities or the Load Frame button from the ConceptBaseWorkbench window (see Figure 4.20).
Figure 4.20: The TelosEditor Field with the object Employee
Now we add an additional attribute, e.g. education, to the class Employee (for the description of the Telos syntax see Appendix A). We have added the line education : String as shown in figure 4.21. To demonstrate error reports from the ConceptBaseWorkbench and how to correct them, we have made mistakes in the syntax notation of the added attribute.
Figure 4.21: Trying to add an attribute to the class Employee with the resulting error report
By clicking the left mouse button on the Tell icon, the content of the editor is told to the ConceptBase server. Syntactical and semantical correctness is checked and the detected errors are reported to the Protocol field. The report resulting from our mistakes by specifying the new attribute is also shown in figure 4.21. Note, that this syntax error would have been already detected at the client side without interaction with the server if we would have enabled the option ``Pre-parse Telos Frames'' in the options menu.
We correct the error by adding a semicolon to the previous line and choose the Tell symbol again. This time, since there are no further mistakes, the additional attribute is added to the class Employee.
Now we can choose again the item Outgoing Attributes from the popup of the Graph Editor window for the node Employee. If we select ``Show all'' attributes of the attribute class ``Attribute'' the new attribute will NOT be shown. The Graph Editor uses an internal cache which will only be updated on request. Therefore, we select the object Employee and select ``Validate and update selected objects'' from the menu ``Current connection''. The cache for the object Employee will be emptied. Now, showing all attributes should add the new attribute education to the graph.