Defining Attributes of Classes

As mentioned in the description of the example-model, the employee-class has several attributes. To add them, we need to modify the Telos frame describing the class Employee.

Exercise 3.2
Load the Telos-Frame defining Employee (using the load frame-button).

You might have recognized, that the frame has changed in a way: the class descriptor Individual has been added at the first position. An explanation for this is given in chapter 2.1 of the User Manual. Modify the Employee-Frame as follows:

Individual Employee in Class with
attribute
        name: String;
        salary: Integer;
        dept: Department;
        boss: Manager
end

Insert the modified Employee-Frame into the object base. Now you have added attributes to the class Employee. They are of the category attribute and their labels are: name, salary, dept, and boss. They establish ``links'' between the class Employee and the classes mentioned as ``targets''. Department and Manager are user-defined classes, while String and Integer are builtin classes of ConceptBase.

Notice that these attributes are also available for the class Manager, because this class is a subclass of Employee (i.e. Telos offers attribute inheritance, see also chapter 2.1 of the User manual, Specialization axiom).

Exercise 3.3:
The Department-class has only one attribute: the manager, who leads the department. Add this attribute to the class Department. The label of this attribute should be head.

Now we have completed the class-level of our example. The next step is to add instances of our classes to the object base.