Extends and replaces variability

The Extends and Replaces variability relationship combines the effects of Extends and Replaces variabilities into one variability type. Whereas Replaces variability completely replaces all attributes and outgoing associations of the base element with new values and instances, or removes all values or associations if the replacing element does not define any, Extends and Replaces variability only replaces values that have been redefined. All other values of the base element are unaffected. In other words, Extends and Replaces allows users to selectively replace specific attributes and associations of the base elements. This type of variability can be used to generate method plug-ins that rename elements, or replace some descriptions of method elements with new ones, without completely remodeling all other relationships and attributes needed by the base plug-in.

Extends and replaces association rules

How to add an extends and replaces association

  1. Use the Content Variability section on the Description tab to make an element extend and replace another element.
  2. Select Extends and Replaces as the Variability type and select the base element that this element will replace. The base element must be the same type of element as the replacing element.