A Note on Context-free Grammars with Rewriting Restrictions∗
نویسنده
چکیده
In this work two special types of random context grammars are investigated. In one of these grammars one can apply a context-free rule to a nonterminal A only if the current sentential form does not contain a particular nonterminal associated toA. The other grammar works in the opposite direction, it requires the presence of the associated nonterminal to apply the rule. Here we show that these systems can generate noncontext-free languages.
منابع مشابه
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تاریخ انتشار 2010