Mike Brown wrote: >> any special reason why "in" is faster if the substring is found, but >> a lot slower if it's not in there? > > Just guessing here, but in general I would think that it would stop searching > as soon as it found it, whereas until then, it keeps looking, which takes more > time.
the point was that string.find does the same thing, but is much faster in the "no match" case. > But I would also hope that it would be smart enough to know that it > doesn't need to look past the 2nd character in 'not the xyz' when it is > searching for 'not there' (due to the lengths of the sequences). note that the target string was "not the xyz"*100, so the search algorithm surely has to look past the second character ;-) (btw, the benchmark was taken from jim hugunin's ironpython talk, and seems to be carefully designed to kill performance also for more advanced algorithms -- including boyer-moore) </F> _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
