UML24 — Ambiguous constraints for transitions

Current UML specification use the two following constraints:

15.3.8 Pseudostate (from BehaviorStateMachines)
Constraint [9] The outgoing transition from an initial vertex may have a behavior, but not a trigger or guard
(self.kind = PseudostateKind::initial) implies (self.outgoing.guard->isEmpty() and self.outgoing.trigger->isEmpty())

15.3.14 Transition (from BehaviorStateMachines)
Constraint [5] Transitions outgoing pseudostates may not have a trigger (except for those coming out of the initial pseudostate)
(source.oclIsKindOf(Pseudostate) and (source.kind <> #initial)) implies trigger->isEmpty()

These constraints are not really contradictory but it is not clear to know if an initial pseudostate can or cannot have a trigger.

In UML 2.5 these constraints have been removed. In fact, there is now a constraint “initial_transition” that makes it
explicit that an initial pseudostate cannot have a trigger.
Disposition: Closed - No Change