re.search much slower then grep on some regular expressions

Henning_Thornblad Henning.Thornblad at gmail.com
Fri Jul 4 13:43:48 CEST 2008


What can be the cause of the large difference between re.search and
grep?

This script takes about 5 min to run on my computer:
#!/usr/bin/env python
import re

row=""
for a in range(156000):
    row+="a"
print re.search('[^ "=]*/',row)


While doing a simple grep:
grep '[^ "=]*/' input                  (input contains 156.000 a in
one row)
doesn't even take a second.

Is this a bug in python?

Thanks...
Henning Thornblad



More information about the Python-list mailing list