Slots and Attribute Management

Slots are meta-objects that manage property-changes of objects. A property is either an attribute or a role in an relation. In a nutshell, a slot has among other attributes:

• a name (which it used to access it),
• a domain (object or class on which it can be used) , and
• can be multivalued or not.

We distinguish between system slots (predefined slots like class, superclass, mixin, instmixin, filter, instfilter) and attribute slots (e.g. attributes of classes).