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arXiv · 0708.0200

A Note on Shortest Developments

Morten Heine Sørensen
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Abstract

De Vrijer has presented a proof of the finite developments theorem which, in addition to showing that all developments are finite, gives an effective reduction strategy computing longest developments as well as a simple formula computing their length. We show that by applying a rather simple and intuitive principle of duality to de Vrijer's approach one arrives at a proof that some developments are finite which in addition yields an effective reduction strategy computing shortest developments as well as a simple formula computing their length. The duality fails for general beta-reduction. Our results simplify previous work by Khasidashvili.

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Morten Heine Sørensen. 2007-08-01. A Note on Shortest Developments. https://doi.org/10.2168/lmcs-3(4:2)2007

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