Every Time You Write a Regular Expression You Should Be Required to Put Sample Input in a Comment
There's a reason PERL has a reputation for being unreadable: regular expressions are almost impossible to decipher without any context. Consider seeing the following in a python script: conf_regex = " *(\d+) +(\d+\.\d+\.\d+\.\d+)/(\d+) +(\d+\.\d+\.\d+\.\d+) +(\d+) +(.+) *" From the variable name you can infer it's being used to parse a conf file, but that's about it. Now compare that to the following: # regex for parsing conf file, example entry below # #id network addr port connections # 0 155.246.80.0/24 127.0.0.1 5000 0,3 conf_regex = " *(\d+) +(\d+\.\d+\.\d+\.\d+)/(\d+) +(\d+\.\d+\.\d+\.\d+) +(\d+) +(.+) *" Suddenly it's not so bad.