CODEWITHSUNDEEP
pythonregex
sheridp
sheridp

Reputation: 1406

Python regex grouping

I am using python's re module and I would like to search and capture one of two possible items, but I can't figure out how to get the grouping and non capturing grouping to work right:

Lets say my pattern is:

(?:(test)55)|(apple)

So basically I want to capture 'test' or 'apple' but only capture 'test' if it is followed by 55.

The problem here is that I end up with 2 capture groups so I end up with either (None, 'apple') or ('test', None).

I know that I can just post-process it:

next( item for item in groups() if item is not None)

but I was wondering if there is a way to phrase it in the regex that would make it work (I just want to learn regex better).

Thanks.

Upvotes: 0

Views: 112

Answers (1)

alexis
alexis

Reputation: 50220

To capture only one group, use just one group of capturing parentheses containing (test|apple). Add a lookahead so that test must be followed by 55:

re.findall(r"(test(?=55)|apple)", mystring);

Upvotes: 1

Related Questions