That's a distinct possibility. Looks like it's time to write to O'Reilly.

Thanks.

Update:

The code should read:

<snip>

sub start_document {
  $self = shift;
  $self->SUPER::start_document(  );
  print "Summary of file:\n";
}

<snip>
[download]

I've sent the correction to O'Reilly. I mentioned your name ;)