An Empirical Study of Rational Tree Unification for miniKanren

We present a study of unification for rational trees in the context of miniKanren. We give the definition of rational trees, specify the unification algorithm and prove some of its properties. We also introduce a number of heuristic optimizations and evaluate them for a number of relevant benchmarks. Finally we discuss the relations between rational and conventional unification algorithms and possible scenarios of their coexistence in the context of relational programming.