== Link: Russ Cox's articles on regular expressions

If you have any interest in regular expression matching,
especially efficient regexps and understanding why Perl,
Python, and so on have [[sometimes oddly slow implementations
../python/MoreRegexpPerformance]], you really want to read
[[Russ Cox's series of articles on regular expressions
http://swtch.com/~rsc/regexp/]].

The core things to read are his three part series,
[[Regular Expression Matching Can Be Simple And Fast
http://swtch.com/~rsc/regexp/regexp1.html]], [[Regular
Expression Matching: the Virtual Machine Approach
http://swtch.com/~rsc/regexp/regexp2.html]], and [[Regular Expression
Matching in the Wild http://swtch.com/~rsc/regexp/regexp3.html]].

(I know, this is late, since Hacker News discussed this a couple of
years ago ([[plus the comment here ../python/MoreRegexpPerformance]]).
The gears of my link-pointing machinery evidently grind very slowly,
but better late than never.)