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arXiv · 1606.06378

First Class Call Stacks: Exploring Head Reduction

Philip Johnson-Freyd·Paul Downen·Zena M. Ariola
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Abstract

Weak-head normalization is inconsistent with functional extensionality in the call-by-name $\lambda$-calculus. We explore this problem from a new angle via the conflict between extensionality and effects. Leveraging ideas from work on the $\lambda$-calculus with control, we derive and justify alternative operational semantics and a sequence of abstract machines for performing head reduction. Head reduction avoids the problems with weak-head reduction and extensionality, while our operational semantics and associated abstract machines show us how to retain weak-head reduction's ease of implementation.

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Philip Johnson-Freyd, Paul Downen, Zena M. Ariola. 2016-06-21. First Class Call Stacks: Exploring Head Reduction. https://doi.org/10.4204/eptcs.212.2

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