Implementation of higher-order unification based on calculus of explicit substitution

Abstract

In this paper, we present several improvements of an algorithm for a higher-order unification based on the calculus of explicit substitutions. The main difference between our algorithm and the already known version is, that we try to postpone normalisation of λσ-terms as long as possible, i.e. until some information of these λσ-terms is necessary for the next step of the unification algorithm.