Question

I am trying to learn regular expressions on my own, hence this silly activity.

I am trying to retrieve any word with “football” in it, but exclude “footballs” from that–so I can get anything else–footballer, footballers, football. Just not “footballs”.

I found that \bfootball(?!s)\b gets rid of both footballers and footballs. How do I only exclude “footballs”?

Answer 1

You must move word boundary inside the assertion:

/\bfootball(?!s\b)/

That is more correct than remove the word boundary at all.
When you remove the boundary at all, you miss the words with s and something after it:
footballsa for example.