Sachin: Just out of curiosity: when you executed the code fragment in the OP with  -W 'no, really' warnings turned on, didn't you get a warning message?

>perl -WMstrict -le
"my $str = 'i am perl: a system';
 my $query = 'perl';
 $str =~ s/$query\W+/<em>$query<\/em> \W+/ig;
 print ' Value = ' . $str;
"
Unrecognized escape \W passed through at -e line 1.
 Value = i am <em>perl</em> W+a system

This should have been a clue.

In reply to Re^5: How to use \W in Regular Expression? by AnomalousMonk
in thread How to use \W in Regular Expression? by Sachin

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