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From: John R Levine <johnl@taugh.com>
Newsgroups: comp.compilers
Subject: TDFA regular expression matching
Date: Thu, 22 Feb 2024 14:28:40 -0500
Organization: Compilers Central
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Keywords: lex, performance
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This 2022 paper describes tagged DFA matching of regular expressions that
have tags to track which input matched where in the regex.  Tagging is
easy when matching with an NFA but harder with a DFA since the tag
locations in the NFA may end up combined or split in the DFA.

It seems pretty clever.  And it does work, implemented in re2c.

https://arxiv.org/abs/2206.01398

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly