pl@nereida:~/Lperltesting$ cat -n ./offsetsin5_10_end.pl
     1  #!/usr/local/lib/perl/5.10.1/bin//perl5.10.1
     2  use v5.10;
     3
     4  my $input;
     5
     6  local $" = ", ";
     7
     8  my $parser = qr{
     9      ^
    10      ((?&expr))
    11      ((?&expr))
    12      \z
    13          (?{
    14               say "main:\n\@- = (@-)\t\t ".scalar(@-)." items\n\@+ = (@+)\t ".scalar(@+)." items\n";
    15          })
    16
    17      (?(DEFINE)
    18          (?<expr>
    19              (.) (.)
    20              (?{
    21                   say "expr:\n\@- = (@-)\t ".scalar(@-)." items\n\@+ = (@+)\t ".scalar(@+)." items\n";
    22              })
    23          )
    24      )
    25  }x;
    26
    27  $input = <>;
    28  chomp($input);
    29  if ($input =~ $parser) {
    30    say "matches: ($&)";
    31    say "At the very end:\n\@- = (@-)\t ".scalar(@-)." items\n\@+ = (@+)\t ".scalar(@+)." items\n";
    32  }