Extending the μLog Framework with Local and Conditional Blackboard Operations

This paper discusses two extensions of the kernel μLog framework presented by Jacquet and De Bosschere (1994): local blackboards and conditional access primitives. The former are needed to alleviate the blackboard communication bottleneck and to solve message naming conflicts whereas the latter improve the message selection power of pattern matching or unification. We propose a syntax for both extensions, give their operational semantics, provide a declarative semantics and prove the soundness and completeness properties in our setting. Moreover,we discuss a specialization of this framework using Prolog astarget language. An implementation is presented and the applicability of the proposed framework and language is argued through the coding of a reactive system.