#!/usr/bin/env perl

use strict;
use warnings;
use autodie;

use constant {
    LINES   => 20_000,
    RECORD  => 'X' x 100 . "\n",
}; 

use Benchmark 'cmpthese';

open my $fh, '>>', '/dev/null';

cmpthese 0 => {
    singly => sub {
        print $fh RECORD for 1 .. LINES;
    },
    concat => sub {
        print $fh join '', (RECORD) x LINES;
    },
    list => sub {
        print $fh +(RECORD) x LINES;
    },
    string => sub {
        print $fh RECORD x LINES;
    },
};

##</code><code>##

         Rate singly   list concat string
singly  437/s     --   -64%   -71%   -91%
list   1205/s   176%     --   -20%   -74%
concat 1497/s   243%    24%     --   -68%
string 4720/s   981%   292%   215%     --