FUML11 — Conditional node and loop node activations do not wait for contained accept event action activations

Specification: Semantics of a Foundational Subset for Executable UML Models (fUML) (formal/2011-02-01)

Subclauses: 8.5.3.2.2 ConditionalNodeActivation, 8.5.3.2.3 LoopNodeActivation, 8.5.4.2.3 ExpansionRegionActivation

The resolution to Issue 17314 (Structured activity node activations do not wait for contained accept event action activations), on adopted on Ballot 2 of the fUML 1.1 RTF, works for plain structured activity nodes, but it does not work for structured activity nodes that are conditional nodes, loop nodes or expansion regions. For conditional nodes, the resumption of suspension of the node must take place in the context of a specific conditional clause. For loop nodes, resumption must allow continued iteration of the loop, rather than just completion of the node activation. For expansion regions, resumption must take place in the context of a specific expansion activation group.

Agreed.

In order to simplify the resolution, it seems unnecessary to allow accept event actions within the test parts of conditional node clauses or loop nodes. Such tests are supposed to be “side effect free” and waiting for an external event to happen is essentially a non-functional side effect. If accept event actions are not allowed in tests, then, for a conditional node, suspension and resumptiuon can only happen in the body of a selected clause with a true test and, for a loop node, it can only happen in the body of the loop.