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just look how it is written! thats not wiki standard! — Preceding unsigned comment added by 79.201.163.93 ( talk • contribs) 09:43, 19 July 2010

That's not very helpful, you know.
But really, this article looks much more like a how-to guide than an encyclopedia article.
- Gabrielkfl ( talk) 01:06, 4 March 2011 (UTC) reply

Point out how some regular expression libraries allow the user to specify a timeout for the evaluation of the regex. For example, The .NET Framework 4.5 has that feature. — Preceding unsigned comment added by 76.102.37.19 ( talk) 10:16, 22 March 2012 (UTC) reply

NFA vs. DFA

This article seems to assume all regex engines are NFA or hybrid NFA/DFA, but pure DFA engines do exists-- and they are not susceptible to this type of attack. Namely, non-GNU awk and non-gnu egrep use pure-DFA engines. ^[1] -- Lucas.Yamanishi ( talk) 21:05, 30 March 2013 (UTC) reply

I think the article name is probably incorrect. “ReDoS” doesn't really seem to have a definition outside of this page, “Catastrophic Backtracking,” while it has fewer total results on a google search, at least seems to unambiguously mean this. PiAndWhippedCream ( talk) 19:32, 1 April 2014 (UTC) reply

The regular expression ^(([a-z])+.)+[A-Z]([a-z])+$ is just wrong for Java class names – it matches e.g. java-lang+String, not just e.g. java.lang.String. If you correct it to ^(([a-z])+\.)+[A-Z]([a-z])+$, it won't produce any backtracking. (Though it is right, the regexp is still found in the wrong way on the linked page, with a warning linking to this page. I'll try to see how to correct that.) -- Paul Ebermann ( talk) 17:22, 23 June 2017 (UTC) reply

It look to me that the example regular expressions could be optimized. Do any implementations optimize such regular expressions? If so, which ones? -- Zzo38 ( talk) 01:30, 23 November 2019 (UTC) reply