SYSML17 — The definition of AdjunctProperty

The definition of AdjunctProperty states that "The AdjunctProperty stereotype can be applied to properties to constrain their values to the values of connectors typed by association blocks, call actions, object nodes, variables, parameters, interaction uses, and submachine states." However, the practical application to a modeler of these different types of adjunct properties is not made explicit in the text.

For example, adjuncts of behavior parameters allows a block's behavior to be bound to its value properties, or those in its ports, and thus solves a long standing problem in the language prior to SysML 1.4.

But when it comes to adjunct properties of activity object nodes the practical application is hard to determine and at the same time it breaks encapsulation by making the behavior's internal state visible and may have a significant impact on the efficiency of model simulation and generated code. The same concerns apply to activity variables.

I am also mystified about the practical application for adjunct properties of interaction uses and sub-machine states (but not a state machine's states). It would be very useful to have a block property that enumerates the current state of an associated state-machine, but as it stands this is not possible by any means that I am aware of (other then by doing it explicitly inside the state-machine's model).

Discuss.