Inverting Functions as Folds

  • Shin-Cheng Mu
  • Richard Bird
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2386)


This paper is devoted to the proof and applications of a theorem giving conditions under which the inverse of a partial function can be expressed as a relational hylomorphism. The theorem is a generalisation of a previous result, due to Bird and de Moor, that gave conditions under which a total function can be expressed a relational fold. The theorem is illustrated with three problems, all dealing with constructing trees with various properties.


Partial Function Functional Programming Level Number Galois Connection Program Construction 
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 2002

Authors and Affiliations

  • Shin-Cheng Mu
    • 1
  • Richard Bird
    • 1
  1. 1.Programming Research GroupOxford UniversityUK

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