Useful Open Call-by-Need

Beniamino Accattoli; Maico Leberle

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arXiv · 2107.06591

Useful Open Call-by-Need

Beniamino Accattoli·Maico Leberle

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Abstract

This paper studies useful sharing, which is a sophisticated optimization for lambda-calculi, in the context of call-by-need evaluation in presence of open terms. Useful sharing turns out to be harder in call-by-need than in call-by-name or call-by-value, because call-by-need evaluates inside environments, making it harder to specify when a substitution step is useful. We isolate the key involved concepts and prove the correctness and the completeness of useful sharing in this setting.

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Beniamino Accattoli, Maico Leberle. 2021-07-14. Useful Open Call-by-Need. https://arxiv.org/abs/2107.06591

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