Use of uninitialized value in concatenation (.) or string Hi, The piece of code works fine but gives a warning message. 
#!/usr/bin/perl -w
use strict;
my %words = map { $_ => 1 } qw($Word $name);
my $line = '$Word $';
$line =~ s/(\$(\w+)?)/exists $words{$1} ? $1 : "dollar$2"/eg;
print "$line\n\n";

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How to initialize the $2. I have to check in array, whether the regular expression matches and if it does not match change the “$” to “dollar”. But if the single character “$” it gives a warning message as “$2” is empty

In reply to Use of uninitialized value in concatenation by gem555

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