Fast Prototyping of a Solver for Reduct-based ELP Semantics

Several semantic approaches have been proposed over time for Epistemic Logic Programs (ELPs), which is an extension to Answer Set Programming (ASP) with epistemic operators. ELP semantics has been defined, in various ways, in terms of world views, which are sets whose elements are sets of atoms. Several semantic approaches are Reduct-based, i.e., extend to ELPs what done for ASP, in the sense that in order to find the world views of a given program they propose to: start with a candidate world view; build the reduct of the program with respect to this candidate world view, according to some specific definition of such reduct; compute the set of stable models of the reduct; check whether the candidate world view is indeed a world view, which is the case if it coincides with the set of stable models of the reduct. Solvers have been developed for some of these approaches, but new semantics/variations have been introduced, and are likely to be introduced in the future, as there is no consensus yet on the “right” semantics. We propose a fast-prototyping approach to obtain a solver for any reduct-based semantics, with the advantage to be able to experiment the approach on small/medium programs, and not only on very small programs as done so far, prior to undertaking the costly process of developing a dedicated solver.