Change propagation and bidirectionality in internal transformation DSLs

Despite good results in several industrial projects, model-driven engineering (MDE) has not been widely adopted in industry. Although MDE has existed for more than a decade now, the lack of tool support is still one of the major problems, according to studies by Staron and Mohaghegi (Staron, in: Model driven engineering languages and systems, Springer, Berlin, 2006; Mohagheghi et al. in Empir Softw Eng 18(1):89–116, 2013). Internal languages offer a solution to this problem for model transformations, which are a key part of MDE. Developers can use existing tools of host languages to create model transformations in a familiar environment. These internal languages, however, typically lack key features such as change propagation or bidirectional transformations. In our opinion, one reason is that existing formalisms for these properties are not well suited for textual languages. In this paper, we present a new formalism describing incremental, bidirectional model synchronizations using synchronization blocks. We prove the ability of this formalism to detect and repair inconsistencies and show its hippocraticness. We use this formalism to create a single internal model transformation language for unidirectional and bidirectional model transformations with optional change propagation. In total, we currently provide 18 operation modes based on a single specification. At the same time, the language may reuse tool support for C#. We validate the applicability of our language using a synthetic example with a transformation from finite state machines to Petri nets where we achieved speedups of up to multiple orders of magnitude compared to classical batch transformations.