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Egress Operation is an Asynchronous Operation or Synchronous Operation

In [MB] it is possible to send a signal to an External Entity. In our metamodel, the same effect results from invoking an Asynchronous Operation. The invoking action does not block waiting for any kind of response from the target Domain. At some point in the future, a response may be recieved in the form of an invocation of an Ingress Operation or some other bridged effect.

Alternatively, a Synchronous Operation may be invoked which will block until whatever requested effect in the target domain completes. If specified, an output value may be yielded as a result of the invocation.

<subclass>.(Name, EE, Domain) -> Egress Operation.(Name, EE, Domain)