use Benchmark 'cmpthese';

my $which = $ARGV[0] || 'short';
my $str = {'short' => "a very short one",
           'long' => "alphabet X alphabet" x 100 . "junk at the end" x 10,
           'shortspaces' => "  asdfasdf fdsdsf a sdfa sdf 3432 324   ",
          }->{$which};

my $duration = 0;
my $verify = 0;
if ($ARGV[1] eq 'verify')
{
    $duration = 1;
    $verify = 1;
}

cmpthese($duration, {
 last =>    sub { my $x = $str; $x =~ s/\s*$//; $method = "last"; print "$x|\n" if $verify; },
 plus =>    sub { my $x = $str; $x =~ s/\s+$//; $method = "plus"; print "$x|\n" if $verify; },
 rx_rx =>   sub { my $x = $str; $x =~ /.*\S/g and $x =~ s/\G.*//; $method = "rxrx"; print "$x|\n" if $verify; },
 sexeger => sub { my $x = $str; ($x = reverse $x) =~ s/^\s+//; $x = reverse $x; $method = "sgxr"; print "$x|\n" if $verify; },
 lookbehind => sub { my $x = $str; $x =~ s/.\K\s+$//; $method = "lkbd"; print "$x|\n" if $verify; },
 detectregex =>  sub { my $x = $str; if ($x =~ /\s/){($x = reverse $x) =~ s/^\s+//; $x = reverse $x;} $method = "dtrs"; print "$x|\n" if $verify; },
 detectsubstr =>  sub { my $x = $str; if (substr($x, -1) =~ /^\s/){($x = reverse $x) =~ s/^\s+//; $x = reverse $x;} $method = "dtss"; print "$x|\n" if $verify;\
 },
               });
__END__

./test long ; ./test short ; ./test shortspaces
                 Rate lookbehind   last  plus detectregex sexeger rx_rx detectsubstr
lookbehind      750/s         --    -5%  -86%        -97%    -97%  -99%        -100%
last            792/s         6%     --  -85%        -96%    -97%  -99%        -100%
plus           5322/s       610%   572%    --        -76%    -77%  -92%         -98%
detectregex   21914/s      2823%  2666%  312%          --     -6%  -68%         -93%
sexeger       23287/s      3006%  2839%  338%          6%      --  -66%         -92%
rx_rx         67557/s      8910%  8426% 1169%        208%    190%    --         -78%
detectsubstr 303483/s     40373% 38201% 5603%       1285%   1203%  349%           --
                 Rate lookbehind last detectregex rx_rx plus sexeger detectsubstr
lookbehind    81153/s         --  -1%        -54%  -59% -67%    -71%         -83%
last          81683/s         1%   --        -54%  -58% -66%    -71%         -83%
detectregex  178253/s       120% 118%          --   -9% -27%    -37%         -63%
rx_rx        196768/s       142% 141%         10%    -- -19%    -30%         -59%
plus         243234/s       200% 198%         36%   24%   --    -14%         -50%
sexeger      282994/s       249% 246%         59%   44%  16%      --         -41%
detectsubstr 481782/s       494% 490%        170%  145%  98%     70%           --
                 Rate lookbehind last plus detectregex detectsubstr rx_rx sexeger
lookbehind    35057/s         --  -9% -72%        -76%         -77%  -80%    -83%
last          38419/s        10%   -- -69%        -74%         -74%  -78%    -82%
plus         123667/s       253% 222%   --        -15%         -18%  -30%    -41%
detectregex  145442/s       315% 279%  18%          --          -3%  -18%    -31%
detectsubstr 149917/s       328% 290%  21%          3%           --  -15%    -29%
rx_rx        176362/s       403% 359%  43%         21%          18%    --    -16%
sexeger      210526/s       501% 448%  70%         45%          40%   19%      --