Partial Bidirectionalization of Model Transformation Languages

While most model-transformation languages in Model-Driven Engineering are unidirectional, bidirectionality is valuable when artifacts need two-way synchronization. Although several bidirectional transformation engines have been developed, their behavior is generally considered more difficult to formulate and predict compared to the unidirectional case. In the bidirectionalization approach, users write the forward direction of their transformations in the same unidirectional language they are used to, and obtain a system that (besides performing the complete forward transformation) can automatically propagate in the backward direction the target updates. When possible, full bidirectionalization is desirable, but far from trivial.