Abstract

The rule labeling heuristic aims to establish confluence of (left-)linear term rewrite systems via decreasing diagrams. We present a formalization of a confluence criterion based on the interplay of relative termination and the rule labeling in the theorem prover Isabelle. Moreover, we report on the integration of this result into the certifier CeTA, facilitating the checking of confluence certificates based on decreasing diagrams for the first time. The power of the method is illustrated by an experimental evaluation on a (standard) collection of confluence problems.

BibTeX

@inproceedings{JNHZ-RTA15,
  author    = "Julian Nagele and Harald Zankl",
  title     = "Certified Rule Labeling",
  booktitle = "Proceedings of the 26th International Conference on Rewriting
               Techniques and Applications (RTA 2015)",
  editor    = "Maribel Fern{\'a}ndez",
  series    = "Leibniz International Proceedings in Informatics"
  volume    = 36,
  pages     = "269--284",
  year      = 2015,
  doi       = "10.4230/LIPIcs.RTA.2015.269"
}