The Equivalence of Context Limited Grammars to Context Free Grammars SCIENTIFIC REPORT
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چکیده
A grammar G is context limited If there exists a partial ordering on the alphabet of G under which, far every production » -♦ 8 of G, every letter of a Is smaller than some letter of 6. It Is proved that the languages generated by context limited grammar«? are .lust the context free languages. Unamblgulty of general grammars Is defined and discussed carefully, preparatory to proving that the languageö generated by unambiguous context limited grammars are Just the unambiguous context free languages. lb January I967 3 TM-73Ö/030/0O THE EQUIVALENCE OF OONTEXT LIMITED GRAWARIJ TO OONTEXT FREE GRAMMARSV) A phrase structure grammar [3, p.8] is here called context limited if there exists a partial ordering on the alphabet of the grammar, under whicn, for every production n B of th« grammar, every letter of » is strictly smaller than sane letter of S.
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تاریخ انتشار 2013