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arXiv · 1405.5599

Analyzing Catastrophic Backtracking Behavior in Practical Regular Expression Matching

Martin Berglund·Frank Drewes·Brink van der Merwe
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Abstract

We develop a formal perspective on how regular expression matching works in Java, a popular representative of the category of regex-directed matching engines. In particular, we define an automata model which captures all the aspects needed to study such matching engines in a formal way. Based on this, we propose two types of static analysis, which take a regular expression and tell whether there exists a family of strings which makes Java-style matching run in exponential time.

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Martin Berglund, Frank Drewes, Brink van der Merwe. 2014-05-22. Analyzing Catastrophic Backtracking Behavior in Practical Regular Expression Matching. https://doi.org/10.4204/eptcs.151.7

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