Issue 17920: Location p 152 Generalization Attributes: IsSubstitutable (uml25-ftf)
Source: Soluta.net (Dr. Adriano Comai, acomai(at)soluta.net)
Nature: Clarification
Severity: Significant
Summary: current text: “isSubstitutable : Boolean [0..1] = true Indicates whether the specific Classifier can be used wherever the general Classifier can be used. If true, the execution traces of the specific Classifier shall be a superset of the execution traces of the general Classifier. If false, there is no such constraint on execution traces. If unset, the modeler has not stated whether there is such a constraint or not.”

[AC] I have always assumed that substitutability is a fundamental characteristic of generalizations, not an option. I may be wrong, of course, but I would like to see in the spec a discussion of this topic. If it is in the spec, I have not found it.

Resolution: 
Revised Text: 
Actions taken:
September 26, 2012: received issue
Discussion: 

End of Annotations:=====
s is issue # 17920

Problem: 9.064

Severity: Medium
Type: Clarification
Location p 152 Generalization Attributes
Title: IsSubstitutable
current text: .isSubstitutable : Boolean [0..1] = true Indicates whether the specific Classifier can be used wherever the general Classifier can be used. If true, the execution traces of the specific Classifier shall be a superset of the execution traces of the general Classifier. If false, there is no such constraint on execution traces. If unset, the modeler has not stated whether there is such a constraint or not..
 
[AC] I have always assumed that substitutability is a fundamental characteristic of generalizations, not an option. I may be wrong, of course, but I would like to see in the spec a discussion of this topic. If it is in the spec, I have not found it.
Source: Adriano Comai