Regex slightly different in Ruby 2?

Question

I just ported a small gem from Ruby 1.9.3 to the spiffy new Ruby 2.0.0. The only change I had to make was in a regular expression.

Under 1.9.3, the following regex would match any string containing characters other than digits, number-related punctuation, and whitespace (including non-breaking space).

/[^[[:space:]]\d\-,\.]/

Under 2.0.0, I had to move the Posix space class away from the start of the negation class.

/[^\d\-,\.[[:space:]]]/

I haven't found this change mentioned in the patch notes I've reviewed. Is it documented anywhere?

Answer 1

The regular expression engine has been changed to Onigmo (based on Oniguruma) and this might be causing issues.

As far as I can tell, you're declaring the regular expression incorrectly. The second set of brackets is not required:

/[^[:space:]\d\-,\.]/

The [:space:] declaration is only invalid inside of a set so you will see it appear as [[:space:]] if used in isolation. In your case you have several other additions to the set.

I'm not sure why \s would not have sufficed in this case.