#!/usr/bin/env perl -l

use strict;
use warnings;
use autodie qw{:all};

use Devel::Size qw{size total_size};

{
    open my $fh, '<', $ARGV[0];

    my @data = <$fh>;

    print 'size(\@data):          ', size(\@data);
    print 'total_size(\@data):    ', total_size(\@data);
}

{
    open my $fh, '<', $ARGV[0];

    my $data_ref;
    @$data_ref = <$fh>;

    print 'size($data_ref):       ', size($data_ref);
    print 'total_size($data_ref): ', total_size($data_ref);
}

{
    open my $fh, '<', $ARGV[0];

    my $data_ref = [ <$fh> ];

    print 'size($data_ref):       ', size($data_ref);
    print 'total_size($data_ref): ', total_size($data_ref);
}