Improving Functional Logic Programs by Difference-Lists

  • Elvira Albert
  • César Ferri
  • Frank Steiner
  • Germán Vidal
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1961)


Modern multi-paradigm declarative languages integrate features from functional, logic, and concurrent programming. Since programs in these languages make extensive use of list-processing functions, we consider of much interest the development of list-processing optimization techniques. In this work, we consider the adaptation of the well-known difference-lists transformation from the logic programming paradigm to our integrated setting. Unfortunately, the use of differencelists is impractical due to the absence of non-strict equality in lazy (callby-name) languages. Despite all, we have developed a novel, stepwise transformation which achieves a similar effect over functional logic programs. We also show a simple and practical approach to incorporate the optimization into a real compiler. Finally, we have conducted a number of experiments which show the practicality of our proposal.


functional logic programming program transformation compiler optimization 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Elvira Albert
    • 1
  • César Ferri
    • 1
  • Frank Steiner
    • 2
  • Germán Vidal
    • 1
  1. 1.Camino de Vera s/nDSIC, UPVValenciaSpain
  2. 2.Institut für InformatikCAU KielKielGermany

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