Abstract
RCB-grammars or regularly controlled bidirectional grammars are context-free grammars of which the rules can be used in a productive and in a reductive fashion. In addition, the application of these rules is controlled by a regular language. Several modes of derivation can be distinguished for this kind of grammar. In this paper the generating power of the derivation mode that uses right-occurrence rewriting (RO-mode) is determined. Furthermore, a new mode called RA is introduced, which is a better formalization of the intuitive idea of right-occurrence rewriting than the RO-mode. The RO- and RA-mode have the same generating power, viz. the corresponding RCB-grammars both generate the recursively enumerable languages. Consequently, providing RCB/RO-grammars with a time bound results in a less powerful grammar model.
Original language | Undefined |
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Pages (from-to) | 75-91 |
Number of pages | 17 |
Journal | International journal of computer mathematics |
Volume | 0 |
Issue number | 40 |
Publication status | Published - 1991 |
Keywords
- HMI-SLT: Speech and Language Technology
- METIS-118470
- EWI-9414
- IR-17951