Tracking Down the Origins of Ambiguity in Context-Free Grammars

  • H. J. S. Basten
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6255)


Context-free grammars are widely used but still hindered by ambiguity. This stresses the need for detailed detection methods that point out the sources of ambiguity in a grammar. In this paper we show how the approximative Noncanonical Unambiguity Test by Schmitz can be extended to conservatively identify production rules that do not contribute to the ambiguity of a grammar. We prove the correctness of our approach and consider its practical applicability.


Equivalence Relation Production Rule Parse Tree Sentential Form Terminal Symbol 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • H. J. S. Basten
    • 1
  1. 1.Centrum Wiskunde & InformaticaAmsterdamThe Netherlands

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