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arXiv · 2007.00605

Effects for Efficiency: Asymptotic Speedup with First-Class Control

Daniel Hillerström·Sam Lindley·John Longley
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Abstract

We study the fundamental efficiency of delimited control. Specifically, we show that effect handlers enable an asymptotic improvement in runtime complexity for a certain class of functions. We consider the generic count problem using a pure PCF-like base language $\lambda_b$ and its extension with effect handlers $\lambda_h$. We show that $\lambda_h$ admits an asymptotically more efficient implementation of generic count than any $\lambda_b$ implementation. We also show that this efficiency gap remains when $\lambda_b$ is extended with mutable state. To our knowledge this result is the first of its kind for control operators.

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Daniel Hillerström, Sam Lindley, John Longley. 2020-07-01. Effects for Efficiency: Asymptotic Speedup with First-Class Control. https://doi.org/10.1145/3408982

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