These days people study regular languages as part of the Chomsky hierarchy, but back when regular expressions were introduced into computing the term referred to Kleene’s regular expressions.
Friedl should be off the list - writing a vaguely competent "user" focused book that butchers the theory (in a way that's had long-running consequences for people's understanding of what an NFA actually is) doesn't put you among the regex greats. Much as I don't agree with many of his approaches to things - most, even - Russ Cox is a far better popularizer of solid regular expression implementation technique and Friedl should be replaced by Cox.
VM Glushkov should be on the list. His NFA formulation both predates Thompson's and has significant advantages for efficient implementation.
Friedl is on the list as an author not as an implementer so I find your comparison to Cox confusing.
I read Friedl's book years ago and I found it incredibly useful.
Whatever damage Friedl did to my understanding of an NFA has been de minimus in comparison to how that book improved my skills. I wish more of my coworkers had encountered Friedl's book.
Agreed. Friedl's book launched my back-end programming career when I followed-up a reference to it in Dreamweaver 8 Bible back in 2000. Along with Programming Perl it's the most inspiring tech book I've ever read.
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[ 2.6 ms ] story [ 40.0 ms ] threadUnderstanding the history of how we got here is crucial.
https://devopedia.org/chomsky-hierarchy
VM Glushkov should be on the list. His NFA formulation both predates Thompson's and has significant advantages for efficient implementation.
I read Friedl's book years ago and I found it incredibly useful.
Whatever damage Friedl did to my understanding of an NFA has been de minimus in comparison to how that book improved my skills. I wish more of my coworkers had encountered Friedl's book.