Modularizing and Evolving Applications using Scripting Modeling Languages

Domain-Independent Models are mainly used for documentation purposes and are most of the time too generic to be directly executed, even by code generation. Domain-Specific Models can sometimes be executed, but their scope is too specific to be reused for other purposes. We have developed a mechanism that allows the creation of modeling languages that will be directly executed into software applications. We were inspired by dynamic languages, especially scripting languages, and adapted their approach to models in order to be able to execute models directly, not for an entire application, but for a specific and well-defined part of it. The goal of scripting languages is to raise the level of abstraction of the host language and to delegate some work to an external language. With the help of two concrete examples, we illustrate that scripting modeling languages can meet this objective better than textual scripting languages and that an application can evolve only by using script models.