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I think all the fuss, misunderstanding and/or over-expectation around regular expression comes from the absence of an important chapter or appendix on MRE. The title of the chapter would be
Things Regular Expression is not Good at, or, limitation of the regexp. For example, it is not good at handling negation-match, conditionals, nesting, etc. In part, the absence gives much ill-effect on those who do not have authentic formal language theory background(?), if I could call it. These days, 99% of the regexp users belong to the group, yes, I am one of them. JF should give helping hands for them in the fourth edition.