#!/usr/bin/perl
use warnings;
use strict;
use Test::More tests => 3;
use Benchmark qw{ cmpthese };

my $short = ['a' .. 'z'];
my $long  = ['a' .. 'zzzzz'];

sub ar {
    my $ar = shift;
    my $mid = @$ar / 2 - 1;
    push my @r, @$ar[ 0 .. $mid ],
                'new',
                @$ar[ $mid + 1 .. $#$ar ];
    \@r
}

sub sp {
    my @r = @{+shift};
    splice @r, @r / 2, 0, 'new';
    \@r
}

diag(scalar @$_) for $short, $long;

is_deeply(ar($short), sp($short), 'same short');
is_deeply(ar($long),  sp($long),  'same long');
is_deeply(ar($short), [ 'a' .. 'm', 'new', 'n' .. 'z' ], 'expected sho
+rt');

cmpthese(-3, {
              'ar-short' => sub { ar($short) },
              'sp-short' => sub { sp($short) },
             });
cmpthese(-10, {
              'ar-long'  => sub { ar($long)  },
              'sp-long'  => sub { sp($long)  },
             });
__END__
Output:

1..3
# 26
# 12356630
ok 1 - same short
ok 2 - same long
ok 3 - expected short
             Rate ar-short sp-short
ar-short 127474/s       --     -21%
sp-short 160522/s      26%       --
        s/iter ar-long sp-long
ar-long   3.12      --    -15%
sp-long   2.64     18%      --
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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