CONTEXTUAL GRAMMARS: PARALLELISM AND BLOCKING OF DERIVATION

Gheorghe P checkA un, Grzegorz Rozenberg, Arto Salomaa

Fundamenta Informaticae · 1996 · 16 citations · 2 references

Concepts

Abstract

Continuing the work begun in [14], we consider contextual grammars (as introduced in [6] with linguistic motivation) with parallel derivations, in which the whole current string participates to a derivation step in the sense that it is splitted into substrings to which contexts are adjoined in a parallel manner. The generative power of such grammars is investigated, when the parallelism is total or partial, and when the selection of contexts is limited to strings in sets of a given type (finite, regular etc.) Then we consider the languages consisting of strings which cannot be further derived (we call them blocking languages). Some open problems are also formulated.

References

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