Communicating session result to calling code

[treiher]

Context and Problem Statement

There is no lightweight way to differentiate a successful from a failed execution of a session state machine, as there is only one final state and no mechanism to communicate data to the "outside world" (except channels).

Considered Options

O1 Return value

Add a return statement (or a similar mechanism) which enables returning an arbitrary value (scalar value or message).

+ Very flexible

O2 Multiple final states identified by name

Multiple final states can be defined. When one of the final states is reached, the corresponding final state is reported as result (as an enum value).

+ Simple
− Conflicts with design decision in #700

O3 Multiple final states identified by previous state

The final state is identified by the null keyword (as decided in #700). The state in which the transition to the final state was taken is reported as result (as an enum value).

+ Simple

Decision Outcome

TBD