However, possessive quantifiers also have other overall effects and uses. Using them can be important to a regular expression working the way you intend (e.g.
this), or it can also cause the regex to do something unexpected, including both unintended matches and failures to match. As usual, it's a good idea to test regexes against a substantial sample of the text which you are wanting to use them on to see if they are really doing what you desire.