These posts are great for history, but regular expression implementation has moved on considerably from early Thompson implementations whether backtracking or N

These posts are great for history, but regular expression implementation has moved on considerably from early Thompson implementations whether backtracking or NFAs. There is a considerable body of literature about regex implementation, including many quite convincing implementations and alternate formulations, some of which weren't even done by people at, or from, Bell Labs! We seem to have something of an Eternal September of regex implementation knowledge (abetted by Russ Cox's amazingly selective bibliography in his posts introducing RE2).