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arXiv · 1804.02906

From Regular Expression Matching to Parsing

Philip Bille·Inge Li Gørtz
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Abstract

Given a regular expression $R$ and a string $Q$, the regular expression parsing problem is to determine if $Q$ matches $R$ and if so, determine how it matches, e.g., by a mapping of the characters of $Q$ to the characters in $R$. Regular expression parsing makes finding matches of a regular expression even more useful by allowing us to directly extract subpatterns of the match, e.g., for extracting IP-addresses from internet traffic analysis or extracting subparts of genomes from genetic data bases. We present a new general techniques for efficiently converting a large class of algorithms that determine if a string $Q$ matches regular expression $R$ into algorithms that can construct a corresponding mapping. As a consequence, we obtain the first efficient linear space solutions for regular expression parsing.

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Philip Bille, Inge Li Gørtz. 2019-01-29. From Regular Expression Matching to Parsing. https://arxiv.org/abs/1804.02906

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