iter.pl

use strict;
use warnings;
use Benchmark qw(cmpthese);
use Iterator::Simple qw(iter islice imap list);

my $n = 1000;
my $size = 10000;
my $start = $ARGV[0] // die;
my $end   = $ARGV[1] // die;
my @list = (1 .. $size);

cmpthese $n => {
    array_ref => sub {
        my $x = \@list;
        my $y = [map { $_ * 2 } @$x];
        [@$y[$start .. $end]];
    },
    array => sub {
        my @y = map { $_ * 2 } @list;
        [@y[$start .. $end]];
    },
    iter => sub {
        my $x = iter(\@list);
        my $y = imap { $_ * 2 } $x;
        my $res = $y->slice($start, $end + 1, 1);
        [@{list($res)}];
    },
};
__END__
$ perl benchmark.pl 0 9999
            Rate      iter     array array_ref
iter      97.0/s        --      -59%      -62%
array      236/s      144%        --       -8%
array_ref  257/s      165%        9%        --

$ perl benchmark.pl 0 999
           Rate     array array_ref      iter
array     621/s        --      -11%      -37%
array_ref 699/s       13%        --      -29%
iter      980/s       58%       40%        --

$ perl benchmark.pl 9999 9999
           Rate      iter     array array_ref
iter      193/s        --      -77%      -78%
array     847/s      340%        --       -5%
array_ref 893/s      363%        5%        --