public function field()
    {
        $field = $this->getAttribute('field');

        if ($field || false === $field) {
            return $field;
        }

        return $this->getAttribute('relation');
    }
public function field()
    {
        $field = $this->getAttribute('field');

        if ($field || false === $field) {
            return $field;
        }

        return $this->getAttribute('relation');
    }
public function field ( ) { $ field = $ this -> getAttribute ( 'field' ) ; if ( $ field || false === $ field ) { return $ field ; } return $ this -> getAttribute ( 'relation' ) ; }
Returns the field key.

@return mixed
Returns the field key .