>perl -wMstrict -le
"my %words = map { $_ => 1 } qw($Word $name);
 my $line = '$Word $ $foo';
 $line =~ s/(\$\w*)/exists $words{$1} ? $1 : qq{ dollar }/eg;
 print $line;
"
$Word  dollar   dollar

[download]
I think the OPer wants '$foo' to be replaced by 'dollarfoo'. And what's with the extra spaces?

In reply to Re^2: Use of uninitialized value in concatenation by AnomalousMonk
in thread Use of uninitialized value in concatenation by gem555

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