use Benchmark 'cmpthese';

my @list = 1 .. 1_000_000;
$result = 0;
cmpthese( 0, {
    list => sub { sub { $result = scalar @_ }->(   @list ) },
    refr => sub { sub { $result = scalar @_ }->( \ @list ) } } );
#          Rate     list     refr
# list   20.2/s       --    -100%
# refr 796087/s 3947995%       --

##</code><code>##

use Benchmark 'cmpthese';

@list = 1 .. 1_000_000;
@result = @list;
$result = \ @list;
cmpthese( 0, {
    list => sub { @result = sub {   @list }->() },
    refr => sub { $result = sub { \ @list }->() } } );
#          Rate      list      refr
# list   1.67/s        --     -100%
# refr 774198/s 46258208%        --