Python regular expressions with more than 100 groups?

If I'm not mistaken, the "new" regex module (currently third-party, but intended to eventually replace the re module in the stdlib) does not have this limit, so you might give that a try.

I found the easiest way was to

import regex as re

instead of

import re

The default _MAXCACHE for regex is 500 instead of 100 I believe. This is one of the many reasons I find regex to be a better module than re.

There is a limit because it would take too much memory to store the complete state machine efficiently. I'd say that if you have more than 100 groups in your re, something is wrong either in the re itself or in the way you are using them. Maybe you need to split the input and work on smaller chunks or something.