On Role Logic
Abstract
We present role logic, a notation for describing properties of relational structures in shape analysis, databases, and knowledge bases. We construct role logic using the ideas of de Bruijn's notation for lambda calculus, an encoding of firstorder logic in lambda calculus, and a simple rule for implicit arguments of unary and binary predicates. The unrestricted version of role logic has the expressive power of firstorder logic with transitive closure. Using a syntactic restriction on role logic formulas, we identify a natural fragment RL^2 of role logic. We show that the RL^2 fragment has the same expressive power as twovariable logic with counting C^2 and is therefore decidable. We present a translation of an imperative language into the decidable fragment RL^2, which allows compositional verification of programs that manipulate relational structures. In addition, we show how RL^2 encodes boolean shape analysis constraints and an expressive description logic.
 Publication:

arXiv eprints
 Pub Date:
 August 2004
 arXiv:
 arXiv:cs/0408018
 Bibcode:
 2004cs........8018K
 Keywords:

 Programming Languages;
 Logic in Computer Science;
 D.2.4;
 D.3.1;
 D.3.3;
 F.3.1;
 F.3.2;
 F.4.1
 EPrint:
 20 pages. Our later SAS 2004 result builds on this work