17.12 Summary

In this chapter, we presented a complete first draft of the airport application, based on the techniques presented in previous chapters. Although the example is complete and meets its stated design goals, we can still make a number of improvements. For example, we could take advantage of Dylan's multiple inheritance to eliminate certain repetitive slots. We could provide a container-implementor module interface, and open the classes and generic functions so that users could add their own classes of containers and extend the scope of the application. We could take advantage of Dylan's exception handling to better deal with unusual situations that might occur during the simulation. In the chapters that follow, we show the Dylan language features that enable such improvements.