Marker-Directed Optimization of UnCAL Graph Transformations
Buneman et al. proposed a graph algebra called UnCAL (Un-structured CALculus) for compositional graph transformations based on structural recursion, and the authors have recently applied to model transformations. The compositional nature of the algebra greatly enhances the modularity of transformations. However, intermediate results generated between composed transformations cause overhead. Buneman et al. proposed fusion rules that eliminate the intermediate results, but auxiliary rewriting rules that enable the actual application of the fusion rules are not apparent so far.