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R56 / 1:1c

Synchronous Operation yields zero or one Egress Output

Egress Output is yielded by exactly one Synchronous Operation

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A Synchronous Operation will yield a result when invoked if an Egress Output is defined.

In the Elevator Case Study, for example, the CABIN.Stop at( floor : Level Name ) : Boolean outputs a false value if the Transport domain cannot execute a stop at the desired floor.

Formalization

Egress Output.(Operation, EE, Domain) -> Synchronous Operation.(Name, EE, Domain)