A formal specification of the jq language

Michael Färber

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arXiv · 2403.20132

A formal specification of the jq language

Michael Färber

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Abstract

jq is a widely used tool that provides a programming language to manipulate JSON data. However, the jq language is currently only specified by its implementation, making it difficult to reason about its behaviour. To this end, we provide a formal syntax and denotational semantics for a large subset of the jq language. Our most significant contribution is to provide a new way to interpret updates that allows for more predictable and performant execution.

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Michael Färber. 2024-03-29. A formal specification of the jq language. https://arxiv.org/abs/2403.20132

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