A Second Comprehensive Application Example - Model-Driven and Software Product Line Engineering - page 202

The constraint between the Characteristic metaconcept
and the Attribute Type feature, constraint2 =
[ Characteristic , Attribute Type , [0..2] , true ] , describes
that product designers can bind Characteristic elements
with the Identifier feature, the Comparable feature, or
both of them. Then on the one hand, elements in the collection
could be unique in terms of one characteristic; for instance, if a
code characteristic is an identifier , then it is not possible
to have two elements in the collection with the same code. On
the other hand, elements in the collection could be ordered
using one sort algorithm as described by the constraint3 .
Figure 7.8. Collection manager constraint model
The constraint3 =[ Characteristic , Sort Algorithm ,
[0..2] , true ], describes that product designers can bind
Characteristic elements with the Insertion feature, the
Bubble feature, or both of them. Then, elements in the
collection could be ordered using the characteristic and any
of the available sort algorithms.
7.4.4. Binding models
Product designers create binding models to configure
products. That is, binding models capture fine-grained