I know this topic has been beaten to death, but I'm not satisfied with the code I came up with, and am looking for a neat/elegant way.

Purpose: sort a list of strings in a way that is useful to humans - so that "foo2bar" comes before "foo10bar", and so forth.

Here is my ugly code (which I think works) 

sub sort_n {
   return
          map
               {
                  $_->[0]   
               }
          sort
               {
                  my $l = @{$a->[1]} < @{$b->[1]}
                          ? scalar @{$a->[1]}
                          : scalar @{$b->[1]} ;

                  for (my $n=0; $n<$l; $n++) {
                     if ( $a->[1][$n] =~ /^(\D+)$/ ) {
                        if ( $b->[1][$n] =~ /^(\D+)$/ ) {
                           my $tmp = $a->[1][$n] cmp $b ->[1][$n];
                           return $tmp if $tmp;
                        } else {
                           return 1;
                        }
                     } else {
                        if ( $b->[1][$n] =~ /^(\D+)$/ ) {
                           return -1;
                        } else {
                           my $tmp = $a->[1][$n] <=> $b ->[1][$n];
                           return $tmp if $tmp;
                        }
                     }
                  }

                  return @{$a->[1]} <=> @{$b->[1]};
               }
          map
               {
                  [
                     $_ ,
                     [
                        # each element of @_ is split on boundaries
                        # between digit and nondigit
                        split (
                                /(?:(?<=\d)(?=\D))|(?:(?<=\D)(?=\d))/,
                                $_
                              )
                     ]
                  ]
               }
          @_;
}

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In reply to sort, semi-numeric by superpete

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