S-semantics -- an example

Abstract

The s-semantics makes it possible to explicitly deal with variables in program answers. So it seems suitable for programs using nonground data structures, like open lists. However it is difficult to find published examples of using the s-semantics to reason about particular programs. Here we apply s-semantics to prove correctness and completeness of Frühwirth's $n$ queens program. This is compared with a proof, published elsewhere, based on the standard semantics and Herbrand interpretations.

Pre-proceedings paper presented at the 31st International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2021), Tallinn, Estonia, and Virtual, September 7-8, 2021 (arXiv:2107.10160). 15 pages, 1 figure. This version -- small modifications