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arXiv · 2410.06769

LR Parsing of Permutation Phrases

Jana Kostičová
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Abstract

This paper presents an efficient method for LR parsing of permutation phrases. In practical cases, the proposed algorithm constructs an LR(0) automaton that requires significantly fewer states to process a permutation phrase compared to the standard construction. For most real-world grammars, the number of states is typically reduced from $\Omega(n!)$ to $O(2^{n})$, resulting in a much more compact parsing table. The state reduction increases with longer permutation phrases and a higher number of permutation phrases within the right-hand side of a rule. We demonstrate the effectiveness of this method through its application to parsing a JSON document.

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Jana Kostičová. 2024-10-09. LR Parsing of Permutation Phrases. https://arxiv.org/abs/2410.06769

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