my($foo, $bar) = (1,2);
my @vars = ($foo, $bar);
foreach my $var (@vars) {
    $var += 4;
}
print "\@vars: @vars\n";
print "\$foo: $foo\n";
print "\$bar: $bar\n";
__END__
@vars: 5 6
$foo: 1
$bar: 2