ON POSITIONED ECO-GRAMMAR SYSTEMS AND PURE GRAMMARS OF TYPE 0
In this paper we extend our results given in [5] where we compared PEG systems with pure regulated context-free grammars (see [3]). We will show that the family of languages generated by the pure grammars of type 0 is a proper subclass of the family of languages generated by positioned eco-grammar systems. We present a way how to coordinate parallel behavior of agents with one-sided context in a PEG system in order to simulate the derivation step in a pure grammar of type 0 determined by a single rule which replaces an arbitrarily long string by another one. Related results concerning PEG systems and pure languages can be found in [6].
positioned eco-grammar systems eco-grammar systems pure grammars