public function append($selector, $value)
    {
        parent::append($selector, $value);

        // if document saved - save through update
        if ($this->getId()) {
            $this->operator->set($selector, $this->get($selector));
        }

        return $this;
    }
public function append($selector, $value)
    {
        parent::append($selector, $value);

        // if document saved - save through update
        if ($this->getId()) {
            $this->operator->set($selector, $this->get($selector));
        }

        return $this;
    }
public function append ( $ selector , $ value ) { parent :: append ( $ selector , $ value ) ; // if document saved - save through update if ( $ this -> getId ( ) ) { $ this -> operator -> set ( $ selector , $ this -> get ( $ selector ) ) ; } return $ this ; }
If field not exist - set value.
If field exists and is not array - convert to array and append
If field is array - append

@param string $selector
@param mixed $value
@return Document
If field not exist - set value . If field exists and is not array - convert to array and append If field is array - append