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The true power of regular expressions (2012)
- ktpsns 3y agoThis is a really nice article. tl,dr: Regexp with backrefs can "solve" NP-hard problems and thus theoretically can parse HTML, but in practice they are not the right tool to do so.
- invpix 3y agoGreat article! Ah someone else also read it through... "Matching of regular expressions is NP-complete. As such you can solve any other NP problem using regular expressions." Would love to see that be the mechanism of that proof.
- precompute 3y agoThis is a great article. I recently tried converting Org-mode files to html with sed and hit a block pretty soon -- sed's extended regex doesn't account for newline characters. That led to me abandoning the project, because even though I had it down 90%, I couldn't make code blocks free from being interpreted as regular org syntax. With PCRE it would have been much easier.