sub Node::climb_up {
  my ($self, $proc) = @_;

  my ($magic, @return);
  my $return = sub {
    @return = @_;
    die \$magic;
  };

  while ($self) {
    eval {
      @return = $proc->($self, $return);
      $self = $self->parent_row;
    };
    if ($@) {
      last if ($@ eq \$magic);
      die $@;
    }
  }

  return @return;
}