Generating code with NTL

Generating code using System.CodeDOM

NMF Transformations does not have any restrictions regarding the input or output models regarding conformance to a framework (such as Models). Thus, it is a neat approach to reuse code models that are widely accepted, such as the code model of the System.CodeDOM namespace. The advantage of this code model is that there are plenty of code generators available that transform these models in a variety of languages. These languages include:

• C#
• VB.NET
• C++/CLI
• F#
• JavaScript.NET

Thus, it is not by chance that these languages are exactly the languages supported by Ecore2Code, the code generator for Ecore metamodels provided by EcoreInterop.

To specify such a code generator, one simply has to write a model transformation that transforms a model into a System.CodeDOM model and then transform this model into code by using a suitable predefined code generator.

(An example is to follow)

Roslyn

However, System.CodeDOM has some strong limitations, as it supports neither lambda expressions nor operator overloading nor a biwise Xor operator. This is due to the fact that System.CodeDom was initially created rather to represent the common concepts of multiple languages, only.

One way out of this dilemma is Roslyn, the brand new open compiler API from Microsoft. The code model used by Roslyn is specific to the used language, so all features of the language can be used. The model is also more fine-grained, so the code generation can be more precise.

However, the code model is also immutable, mainly for reasons of clean parallel programming. This makes the Roslyn model absolutely unsuitable for code generation. So, to use Roslyn and NTL, the very best idea is to wait for some mutable Roslyn wrapper.