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arXiv · 2306.13756

A Fully Abstract Model of PCF Based on Extended Addressing Machines

Benedetto Intrigila·Giulio Manzonetto·Nicolas Munnich
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Abstract

Extended addressing machines (EAMs) have been introduced to represent higher-order sequential computations. Previously, we have shown that they are capable of simulating -- via an easy encoding -- the operational semantics of PCF, extended with explicit substitutions. In this paper we prove that the simulation is actually an equivalence: a PCF program terminates in a numeral exactly when the corresponding EAM terminates in the same numeral. It follows that the model of PCF obtained by quotienting typable EAMs by a suitable logical relation is adequate. From a definability result stating that every EAM in the model can be transformed into a PCF program with the same observational behavior, we conclude that the model is fully abstract for PCF.

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Benedetto Intrigila, Giulio Manzonetto, Nicolas Munnich. 2023-06-23. A Fully Abstract Model of PCF Based on Extended Addressing Machines. https://doi.org/10.46298/lmcs-21(3%3A17)2025

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