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Grammars With Two-Sided Contexts

Mikhail Barash, Alexander Okhotin, Grammars With Two-Sided Contexts. TUCS Technical Reports 1090, Turku Centre for Computer Science, 2013.


In a recent paper (M. Barash, A. Okhotin, "Defining contexts in context-free grammars", LATA 2012), the authors introduced an extension of the context-free grammars equipped with an operator for referring to the left context of the substring being defined. This paper proposes a more general model, in which context specifications may be two-sided, that is, both the left and the right contexts can be specified by the corresponding operators. The paper gives the definitions and establishes the basic theory of such grammars, leading to a parsing algorithm working in time O(n^(omega+1)), where n is the length of the input string and omega is the exponent of matrix multiplication complexity.


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BibTeX entry:

  title = {Grammars With Two-Sided Contexts},
  author = {Barash, Mikhail and Okhotin, Alexander},
  number = {1090},
  series = {TUCS Technical Reports},
  publisher = {Turku Centre for Computer Science},
  year = {2013},
  keywords = {Context-free grammars, conjunctive grammars, contexts, context-sensitive grammars, parsing.},

Belongs to TUCS Research Unit(s): FUNDIM, Fundamentals of Computing and Discrete Mathematics

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