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arXiv · 1805.10438

Confluence of CHR revisited: invariants and modulo equivalence

Henning Christiansen·Maja H. Kirkeby
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Abstract

Abstract simulation of one transition system by another is introduced as a means to simulate a potentially infinite class of similar transition sequences within a single transition sequence. This is useful for proving confluence under invariants of a given system, as it may reduce the number of proof cases to consider from infinity to a finite number. The classical confluence results for Constraint Handling Rules (CHR) can be explained in this way, using CHR as a simulation of itself. Using an abstract simulation based on a ground representation, we extend these results to include confluence under invariant and modulo equivalence, which have not been done in a satisfactory way before.

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Henning Christiansen, Maja H. Kirkeby. 2018-05-26. Confluence of CHR revisited: invariants and modulo equivalence. https://arxiv.org/abs/1805.10438

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