Unified Decision Procedures for Regular Expression Equivalence

  • Tobias Nipkow
  • Dmitriy Traytel
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8558)


We formalize a unified framework for verified decision procedures for regular expression equivalence. Five recently published formalizations of such decision procedures (three based on derivatives, two on marked regular expressions) can be obtained as instances of the framework. We discover that the two approaches based on marked regular expressions, which were previously thought to be the same, are different, and we prove a quotient relation between the automata produced by them. The common framework makes it possible to compare the performance of the different decision procedures in a meaningful way.


Partial Derivative Decision Procedure Regular Expression Recursive Function Proof Assistant 
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 International Publishing Switzerland 2014

Authors and Affiliations

  • Tobias Nipkow
    • 1
  • Dmitriy Traytel
    • 1
  1. 1.Fakultät für InformatikTechnische Universität MünchenGermany

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