These pages describe a system for compiling nested logic programs into disjunctive logic programs under answer set semantics . Our system is conceived as a front-end to the logic programming systems dlv and (since recently) gnt.
The underlying compiler is implemented in the programming language Prolog; it has been developed under the Logic Programming Systems SICStus and SWI; its code employs standard Prolog programming constructs so that it remains portable to other Prolog systems.
We deal with nested logic programs under the answer set semantics  which is an extension of the stable models semantics  for handling logic programs with classical negation.
An excellent introduction to logic programming under these semantics is due to Vladimir Lifschitz and can be accessed through his home-page.
This emerging subfield common to logic programming and nonmonotonic reasoning is also referred to Answer Set Programming. Some links on the subject are given here.