Maximally Parallel Contextual String Rewriting

This paper introduces contextual string rewriting as a special kind of parallel string rewriting in which each rule defines a context which is not changed by the application of the rule and can be read (but not modified) by other rules applying concurrently. We study maximal parallel rewriting in this setting and provide a method to encode the computation of a maximally parallel instance for a contextual string rewrite system as a decidable normal form problem for a particular term rewrite system.