Type-Inference Based Short Cut Deforestation (Nearly) without Inlining

  • Olaf Chitil
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1868)


Deforestation optimises a functional program by transforming it into another one that does not create certain intermediate data structures. Our type-inference based deforestation algorithm performs extensive inlining, but only limited inlining across module boundaries is practically feasible. Therefore we here present a type-inference based algorithm that splits a function definition into a worker definition and a wrapper definition. For deforestation we only need to inline the small wrappers which transfer the required information. We show that we even can deforest definitions of functions that consume their own result with the worker/wrapper scheme, in contrast to the original algorithm with inlining.


Type Variable Fusion Rule Recursive Call Functional Program Module Boundary 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Olaf Chitil
    • 1
  1. 1.Lehrstuhl für Informatik IIRWTH AachenGermany

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