Chapter 13. Advanced Topics

In this chapter, we will describe a few advanced topics concerning an Xtext DSL implementation, and some advanced techniques. In the first part of the chapter, we will show how to manually maintain the Ecore model for the AST of an Xtext DSL. This way, you will have full control on the shape of the AST, instead of delegating that to the automatic Xtext Ecore inference mechanisms. Of course, the Xtext grammar and the Ecore model will still have to be consistent, but you will be able tweak the AST structure. You will also be able to add to the AST some derived state, which is computed from the DSL program, but which is not directly present in the program itself. In the first section, we will show how to create an Xtext DSL starting from an existing Ecore model, while in the second section, we will show how to switch to a manually maintained Ecore model, starting from the one generated by Xtext. In the third section, we will use Xcore to maintain the...