Publication Details
Bidirectional Contextual Grammars
contextual grammars, bidirectional grammars, generative power, recursively enumerable languages
The present paper introduces and discusses bidirectional contextual grammars as a straightforward generalization of externally generating contextual grammars without choice. In essence, besides ordinary derivation steps, the bidirectional contextual grammars can also make reduction steps, which shorten the rewritten strings. This paper demonstrates that these grammars characterize the family of recursively enumerable languages. In fact, this characterization holds even in terms of one-turn bidirectional contextual grammars, which can change derivations steps to reduction steps during the generation process no more than once.
@INPROCEEDINGS{FITPUB8044,
author = "Ji\v{r}\'{i} Techet",
title = "Bidirectional Contextual Grammars",
pages = "61--68",
booktitle = "Proceedings of 1st International Workshop WFM '06",
year = 2006,
location = "P\v{r}erov, CZ",
ISBN = "80-86840-20-4",
language = "english",
url = "https://www.fit.vut.cz/research/publication/8044"
}