Yes definitely a different thing when talking about ‘extended regex’ libraries, wrt to the regular languages (language class) and associates recognizers. That

Yes definitely a different thing when talking about ‘extended regex’ libraries, wrt to the regular languages (language class) and associates recognizers. That said, even modern pcre uses state machines https://github.com/rurban/pcre/blob/master/src/pcre2_dfa_match.c https://github.com/rurban/pcre/blob/master/src/pcre2_dfa_mat...