Metric Lexical Analysis

  • Cristian S. Calude
  • Kai Salomaa
  • Sheng Yu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2214)


We study automata-theoretic properties of distances and quasi-distances between words. We show that every additive distance is finite. We also show that every additive quasi-distance is regularitypreserving, that is, the neighborhood of any radius of a regular language with respect to an additive quasi-distance is regular. As an application we present a simple algorithm that constructs a metric (fault-tolerant) lexical analyzer for any given lexical analyzer and desired radius (faulttolerance index).


Formal Language Regular Language Hash Code Lexical Analyzer Nondeterministic Choice 
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 2001

Authors and Affiliations

  • Cristian S. Calude
    • 1
  • Kai Salomaa
    • 2
  • Sheng Yu
    • 3
  1. 1.Computer Science DepartmentThe University of AucklandPrivate BagAucklandNew Zealand
  2. 2.Department of Computing and Information ScienceQueen’s UniversityKingstonCanada
  3. 3.Department of Computer ScienceThe University of Western OntarioLondonCanada

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