Default Enaction

A default enaction of a use case description is a stateless enaction process. This means that dependencies amongst description events are assumed to be linear. Thus, events are stepped through from the first to the last. The successive events are availed with a  presumption that the preceding events succeeded.

For a car parking system involving Driver and Ticket machine as actors, the events would be enacted in this order:

1. Driver drives to ticket machine

2. Driver presses the ticket button

3. Ticket machine dispenses the ticket

4. Driver takes the ticket

The tool would show enaction thus:

Event 1:

Event 2:

Event 3

Event 4

See example of a state-based enaction.