====usual variable substitution idiom for comparison====
my $lamb = 'wolf';
my $text = 'Mary had a little $lamb.';
$text =~ s/(\$\w+) /$1/eeg;
print $text; #    ^------------- ?

##</code><code>##

$text =~ s/(\$\w+)/$1/eeg;
print $text;
__END__
Mary had a little wolf.