UMLR — Does not seem possible to have an exception cause an interrupt (leave the region)

Because of they use the same notation. an exception handler and the target of a interrupting edge look identical. However, the semantics are quite different. In the exception handler case, tokens are emitted from the protected behavior. In the interrupting edge case, tokens in the region are abandoned, and instead leave from the interrupting edge "handler"

1) the notation is too similar and confusing to modelers and readers.
2) It's not possible to have an exception cause a region to be abandoned. This is a common and desirable situation
3) In some circumstances it would be impossible to distinguish between an exception handler and interruptible region "handler". Imagine an exception handler whose exception edge crosses an interruptible region boundary. The only way to be sure it was an interruptible region handler is if it has outgoing edges. Without them, it could be either.