A uniform integration of higher-order reasoning and external evaluations in answer-set programming 论文

摘要

We introduce HEX programs, which are nonmono-tonic logic programs admitting higher-order atoms as well as external atoms, and we extend the well-known answer-set semantics to this class of pro-grams. Higher-order features are widely acknowl-edged as useful for performing meta-reasoning, among other tasks. Furthermore, the possibility to exchange knowledge with external sources in a fully declarative framework such as Answer-Set Programming (ASP) is nowadays important, in par-ticular in view of applications in the Semantic Web area. Through external atoms, HEX programs can model some important extensions to ASP, and are a useful KR tool for expressing various applications. Finally, complexity and implementation issues for a preliminary prototype are discussed. 1