use strict;
use Data::Dumper;
my $ref = sub { print Dumper \@_ };
    ()->$ref;
    do{}->$ref;
    ()->$ref();
    do{}->$ref();
__END__
$VAR1 = [
          undef
        ];
$VAR1 = [
          undef
        ];
$VAR1 = [
          undef
        ];
$VAR1 = [
          undef
        ];