Python regex: error: don't repeat anything

Question

I use re.sub() to remove color management codes (IRC) from the string, but it fails every time. This is what I use:

 re.sub('\x03(\d*)?,?(\d*)?', '', content) 

Error:

  File "/usr/lib/python2.7/re.py", line 151, in sub return _compile(pattern, flags).sub(repl, string, count) File "/usr/lib/python2.7/re.py", line 242, in _compile raise error, v # invalid expression error: nothing to repeat 

I don't see anything wrong with my regex, so can someone explain what I'm doing wrong?

Answer 1

Your regex is legal, but the Python regex implementation has an error that causes it to reject nested optional quantifiers in some cases.

You still do not need (...)? es:

 re.sub('\x03\\d*,?\\d*', '', content)