Issue
In shell scripting we have \t for tab, \s for whitespace, \w for word.
What are \W (capital W) and \D (capital D) used for?
Solution
\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]
Answered By - Jerry Answer Checked By - Terry (WPSolving Volunteer)