Implementation Of Logical Retraction In Constraint Handling Rules With Justifications

In previous work we added justifications to Constraint Handling Rules (CHR) to enable logical retraction of constraints for dynamic algorithms. We presented a straightforward source-to-source transformation to implement this conservative extension. In this companion paper, we improve the performance of the transformation. We discuss its worstcase time complexity in general. Then we perform experiments. We benchmark the dynamic problem of maintaining shortest paths under addition and retraction of paths. The results validate our complexity considerations.