Subregularly Tree Controlled Grammars and Languages
نویسندگان
چکیده
Tree controlled grammars are context-free grammars where the associated language only contains those terminal words which have a derivation where the word of any level of the corresponding derivation tree belongs to a given regular language. We present some results on the power of such grammars where we restrict the regular languages to some known subclasses of the family of regular languages.
منابع مشابه
On Two Hierarchies of Subregularly Tree Controlled Languages
Tree controlled grammars are context-free grammars where the associated language only contains those terminal words which have a derivation where the word of any level of the corresponding derivation tree belongs to a given regular language. In this paper, we consider first the case that we take only such regular languages as the control set which can be represented by finite unions of monoids....
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