Trees as Contexts in Formal Language Generation

摘要

Initially designed to generate languages without rewriting of some nonterminals, contextual grammars are used in formal language theories as well as models for several particular aspects of natural languages. However, despite their power, contextual grammars do not provide a structural description of the generated languages. We present several modalities to add structures to classical contextual grammars. We are studying the relations of these structured contextual languages comparing with other structured languages. Several examples show the potential of the newly introduced grammars.