@sorted = map  { $_->[0] }
          sort { $a->[1] <=> $b->[1] } # use numeric comparison
          map  { [$_, length($_)] }    # calculate the length of the string
               @unsorted;

##</code><code>##

#!/usr/bin/perl

use strict;
use Devel::Peek;

my @arr = (22, 5.555, 1, 4444, 333);

print Dump(\@arr, @arr+0), "\n\n\n";
# at this point, there are 4 IVs and one NV in our array;
# naturally, none of the elements have their length ("CUR") field set

my ($retval, $just_once);

my @sorted = sort {
    # does this alter the internal structures of our actual
    # array elements, turning IVs and NVs into PVIVs/PVNVs?
    $retval = length $a <=> length $b;

    print Dump \@arr, @arr+0 if !$just_once++;
    # of course it does!

    $retval;
} @arr;

print "\nsorted = @sorted\n";