Critical Pair Analysis in Nominal Rewriting

Nominal rewriting (Fernández, Gabbay & Mackie, 2004;Fernández & Gabbay, 2007) is a framework that extendsfirst-order term rewriting by a binding mechanismbased on the nominal approach (Gabbay & Pitts, 2002;Pitts, 2003). In this paper, we investigate confluenceproperties of nominal rewriting, following the study oforthogonal systems in (Suzuki et al., 2015), but herewe treat systems in which overlaps of the rewrite rulesexist. First we present an example where choice ofbound variables (atoms) of rules affects joinability ofthe induced critical pairs. Then we give a detailedproof of the critical pair lemma, and illustrate someof its applications including confluence results fornon-terminating systems.