word-boundaries

What are non-word boundary in regex (\B), compared to word-boundary? A word boundary ( \b ) is a zero width match that can match: Between a word character ( \w ) and a non-word character ( \W ) or Between a word character and the start or end of the string. In Javascript the definition of \w is [A-Za-z0-9_] and \W is anything else. The negated version of \b , written \B , is a zero width match where the above does not hold. Therefore it can match: Between two word characters. Between two non-word characters. Between a non-word character and the start or end of the string. The empty string. For