code: protected function parse_string() {
  		$char = $this->doc[$this->pos];
  
  		while (true) {
  			if ($this->next_search($char.'\\', false) !== self::TOK_NULL) {
  				if($this->doc[$this->pos] === $char) {
  					break;
  				} else {
  					++$this->pos;
  				}
  			} else {
  				$this->pos = $this->size - 1;
  				break;
  			}
  		}
  
  		return ($this->token = self::TOK_STRING);
  	}
docs: Parse strings (" and ')
  @return int