The dynamics of many calculi can be msot clearly defined by a reduction semantics.To work with a calculus,however,an understanding of operational congruences is fundamental; these cna often be given tractable defintions or characteisations using a labelled transition semantics.This paper ocnsidrs calculi with arbitrary reduction semantics of three simple classes,firstly ground term rewriting,then left-linear term rewriting,and then a class which is ess4entially the action calculi lacking substantive name binding.
展开▼
