Result: Handle undefined type or train_no

sub line {

	my ($self) = @_;

	return

	  sprintf( '%s %s', $self->{type}, $self->{line_no} // $self->{train_no} );

	return sprintf( '%s %s',

		$self->{type} // 'Zug',

		$self->{line_no} // $self->{train_no} // '-' );

}

sub route_pre {