World Scientific
Skip main navigation

Cookies Notification

We use cookies on this site to enhance your user experience. By continuing to browse the site, you consent to the use of our cookies. Learn More
×

System Upgrade on Tue, May 28th, 2024 at 2am (EDT)

Existing users will be able to log into the site and access content. However, E-commerce and registration of new users may not be available for up to 12 hours.
For online purchase, please visit us again. Contact us at customercare@wspc.com for any enquiries.

DERIVATION TREES FOR CONTEXT-SENSITIVE GRAMMARS

    https://doi.org/10.1142/9789814317610_0013Cited by:2 (Source: Crossref)
    Abstract:

    One of the main reasons that context-free grammars are widely used is the fact that the concept of derivation trees fits to them very well. The left-most derivations play important role both in theory and practice. Unfortunately with left-most derivations only context-free languages can be derived even if the rules of the grammar are not context-free. In this paper we investigate derivation trees for context-sensitive grammars based on Penttonen's one-sided normal form. The concept of the presented derivation graphs are a kind of extension of the well-known context-free derivation-trees. Moreover it allows to define left-most derivations in context-sensitive grammars without loosing the efficiency of the derivations. These left-most derivations are not derivations in the usual sentential form sense. They are the generalizations of the classical (context-free) left-most derivations, in the way of constructing a derivation tree. Some examples and a new type of ambiguity are also shown.