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Rules for Assigning Exit State Definitions

When an exit state is set during a procedure step execution, the results must be unambiguous.

The following rules govern the assignment of exit state definitions to dialog flows:

The following illustration, Exit State Rule Violation, shows violations of both rules using an annotated Dialog Flow Diagram.

Exit State Rule Violation

The illustration shows three procedures, P1, P2 and P3, and six dialog flows, each of which has been assigned a number. The Flows On and Returns On Exit States associated with each flow are also listed.

Despite the confused use of exit states in this diagram, there are actually only two violations:

This discussion reveals an interesting property of Returns On exit states; they depend entirely on the context of a particular link.

The following illustration, Context Sensitivity of Returns on Exit States, shows that both Take Order and Change Order can link to Maintain Customer. (Assume that the Returns On Exit State for both links is Request Successful.)

Context Sensitivity of Returns on Exit States

According to this illustration, there are three possible results if MAINTAIN CUSTOMER sets Request Successful during its execution:

The result depends on how MAINTAIN CUSTOMER was initiated.