This is the revision history for r in <freenode.net:#regex>

factoid_idsubjectcopulapredicateauthornamespace
12290 r is http://www.regular-expressions.info/rlanguage.html which describes multiple regex flavors for R, including PCRE, POSIX BRE and ERE. onlinecop
12287 r is http://www.regular-expressions.info/rlanguage.html which describes multiple regex languages, including PCRE, POSIX BRE and ERE. onlinecop