I'm not sure what your final point is? Doing this:
cmpthese( -2,{
 list => sub { &list },
 shiftit => sub { &shiftit },
} );

[download]
seems just plain broken, and I wouldn't have been surprised if it even made Benchmark roll over and die. You shouldn't be making any assumptions about what is in @_ in your outer sub {}, much less modifiying it.

Trying this: 

use Benchmark 'cmpthese';
cmpthese(1, { tryit => sub { $save = \@_ }});
use Data::Dumper;
$Data::Dumper::Deparse = 1;
print Dumper $save;
__END__
$VAR1 = [
          1,
          sub {
                  $save = \@_;
              }
        ];

[download]
shows that in fact, cmpthese's parameters are still in @_, and doing: 
cmpthese 3, { tryit => sub { push @save, [@_]; shift } };
print Dumper \@save;
$VAR1 = [
          [
            3,
            sub {
                  push @save, [@_];
                  shift @_;
              }
          ],
          [
            $VAR1->[0][1]
          ],
          []
        ];

[download]
shows that your shift has blown them away after the first 2 iterations.

In reply to Re: Lies, Damn Lies and Benchmarks by ysth
in thread Lies, Damn Lies and Benchmarks by liz

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.