\W
is the opposite of \w
and \D
is the opposite of \d
.
It’s just like \S
is the opposite of \s
.
\W
and \D
respectively will match what \w
and \d
respectively don’t match.
You can have a look at this site for some more explanation.
\w
typically matches [A-Za-z0-9_]
(ignoring the foreign characters)
\W
thus matches [^A-Za-z0-9_]
And since
\d
typically matches [0-9]
(ignoring the foreign digits)
\D
thus matches [^0-9]