Python Regular Expression: why does this not work?

Question

This does not give me an error nor an answer.

re.sub('\\.(\\W|\\.)*[o0](\\W|[o0])*', '*', '..........................................')  

Why does it behave like so? Also, if I reduce the amount of 'periods', then it works.

Thank you.

Answer 1

You've got catastrophic backtracking.