The External Interface for Extending WASP. Issue 2 (10th March 2020)

• Record Type: Journal Article
• Authors: DODARO, CARMINE; RICCA, FRANCESCO
• Is Part Of: Theory and practice of logic programming. Volume 20:Issue 2(2020)
• Page Start: 225
• Page End: 248
• Publication Date: 2020-03-10
• Subjects: knowledge representation and reasoning, -- answer set programming, -- application programming interface, -- propagators, -- choice heuristics; Logic programming -- Periodicals; Artificial intelligence -- Computer programs -- Periodicals; Constraint programming (Computer science) -- Periodicals; 005.115
• DOI: 10.1017/S1471068418000558
• Languages: English
• ISSNs: 1471-0684

Abstract

Abstract : Answer set programming (ASP) is a successful declarative formalism for knowledge representation and reasoning. The evaluation of ASP programs is nowadays based on the conflict-driven clause learning (CDCL) backtracking search algorithm. Recent work suggested that the performance of CDCL-based implementations can be considerably improved on specific benchmarks by extending their solving capabilities with custom heuristics and propagators. However, embedding such algorithms into existing systems requires expert knowledge of the internals of ASP implementations. The development of effective solver extensions can be made easier by providing suitable programming interfaces. In this paper, we present the interface for extending the CDCL-based ASP solver wasp. The interface is both general, that is, it can be used for providing either new branching heuristics or propagators, and external, that is, the implementation of new algorithms requires no internal modifications of wasp. Moreover, we review the applications of the interface witnessing it can be successfully used to extend wasp for solving effectively hard instances of both real-world and synthetic problems.