Debugging Answer-Set Programs with Ouroboros – Extending the SeaLion Plugin?

Abstract. In answer-set programming (ASP), there is a lack of debug-ging tools that are capable of handling programs with variables. Hence, we implemented a tool, called Ouroboros, for debugging non-ground answer-set programs. The system builds on a previous approach based on ASP meta-programming that has been recently extended to cover weight constraints and choice rules. The main debugging question addressed is “given a program P and an interpretation I, why is I not an answer set of P”. Our tool gives answers in terms of two categories of expla-nations: unsatisfied rules and unfounded loops. Ouroboros is a plugin of the SeaLion integrated development environment for ASP that is built on Eclipse. Thereby, Ouroboros complements and profits from SeaLion’s Stepping plugin, that implements a different debugging approach for ASP.