protected function advanceKey()
    {
        if ($this->isScrollable() && ($this->documents[$this->key()] == end($this->documents))) {
            $this->page();
        } else {
            $this->key++;
        }

        return $this;
    }
protected function advanceKey()
    {
        if ($this->isScrollable() && ($this->documents[$this->key()] == end($this->documents))) {
            $this->page();
        } else {
            $this->key++;
        }

        return $this;
    }
protected function advanceKey ( ) { if ( $ this -> isScrollable ( ) && ( $ this -> documents [ $ this -> key ( ) ] == end ( $ this -> documents ) ) ) { $ this -> page ( ) ; } else { $ this -> key ++ ; } return $ this ; }
Advances key.

@return $this
Advances key .