In order to enable logic programming to deal with the diversity of pervasive systems, where many heterogeneous, domain-specific computational models could benefit from the power of symbolic computation, we explore the expressive power of labelled systems.
To this end, we define a new notion of truth for logic programs extended with labelled variables interpreted in non-Herbrand domains—where, however, terms maintain their usual Herbrand interpretations.

First, a model for labelled variables in logic programming is defined. Then, the fixpoint and the operational semantics are presented and their equivalence is formally proved. A meta-interpreter implementing the operational semantics is also introduced, followed by some case studies aimed at showing the effectiveness of our approach in selected scenarios.