You are confirming what I suspected...And I understand what you are saying... The only problem is that I tried your code and it doesn't seem to give the expected result

#!/usr/bin/perl

use warnings;
use strict;

my $foo = undef;
my $bar = 'bar';
$foo = $foo . $bar; # UNITIALIZED!!!

print "foo = <$foo>\n";
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prints: foo = <bar>
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So thanks for the help though, It still help's me understand what is happening.