$ perl -le'
    use Data::Dumper;
    $x = ( 4, 5, 6, 7 );
    print Dumper $x;
'
$VAR1 = 7;

$ perl -le'
    use Data::Dumper;
    $x = \( 4, 5, 6, 7 );
    print Dumper $x;
'
$VAR1 = \7;

$ perl -le'
    use Data::Dumper;
    $x = ( \4, \5, \6, \7 );
    print Dumper $x;
'
$VAR1 = \7;