On Tue, 11 May 2010 17:48:41 +1200, Lawrence D'Oliveiro wrote: >> I was working with regex on a very large text, really large but I have >> time constrained. > > “Fast regex” is a contradiction in terms.
Not at all. A properly-written regexp engine will be limited only by memory bandwidth, provided that the state table fits into the primary cache. > You use regexes when you > want ease of definition and application, not speed. Other way around. > For speed, consider hand-coding your own state machine. Preferably in a > compiled language like C. Or use a decent regexp library. Even if you want to use non-regular expressions (e.g. backreferences), a decent engine will still use a DFA, bactracking only where strictly necessary. -- http://mail.python.org/mailman/listinfo/python-list
