"Learned" in University but it wasn't until Jeff Friedl's Perl Conference talks that I really became one with the regex engine. He taught you how to think like

"Learned" in University but it wasn't until Jeff Friedl's Perl Conference talks that I really became one with the regex engine. He taught you how to think like the regex engine and thus how regular expressions would be interpreted and thus how to write them. Then I got a master class in RE from Tom Christiansen when we were writing the Perl Cookbook. Jeff wrote "Mastering Regular Expressions", which grew from that talk. You probably want a copy even though it was first released in 1997. For the mindset of RE, you can't beat it. Learning REs is a roll through: * how matching happens (advancing, matching, backtracking) * using * ? and {} to match repetitions * greediness and stinginess within the RE * character classes, both [manual] and escapes like \s \W etc * anchors and "what a line is" * grouping and backreferences * accessing groups outside the RE * substitution and access backrefs in substitutions * find ALL the matches * complex parsing (just don't, it's rare not to regret it) and then it's an absolutely epic deep-dive into the minutiae of what line starts and ends might be, Unicode and regex, code to be executed from within the regex enging, using code to BUILD regex and worrying about when escaping happens or doesn't, denial of service regex, etc. that will take you through ASCII, various Unix tool chains over time, and a bunch of other fun stuff.