Doctrine\ORM\Query\Parser::syntaxError PHP 메소드

    public function syntaxError($expected = '', $token = null)
    {
        if ($token === null) {
            $token = $this->_lexer->lookahead;
        }

        $tokenPos = (isset($token['position'])) ? $token['position'] : '-1';
        $message  = "line 0, col {$tokenPos}: Error: ";

        if ($expected !== '') {
            $message .= "Expected {$expected}, got ";
        } else {
            $message .= 'Unexpected ';
        }

        if ($this->_lexer->lookahead === null) {
            $message .= 'end of string.';
        } else {
            $message .= "'{$token['value']}'";
        }

        throw QueryException::syntaxError($message);
    }

 /**
  * @url http://sysmagazine.com/posts/181666/
  *
  * {@inheritdoc}
  */
 public function parse(Parser $parser)
 {
     $parser->match(Lexer::T_IDENTIFIER);
     $parser->match(Lexer::T_OPEN_PARENTHESIS);
     $lexer = $parser->getLexer();
     if ($lexer->isNextToken(Lexer::T_DISTINCT)) {
         $parser->match(Lexer::T_DISTINCT);
         $this->parameters[self::DISTINCT_KEY] = true;
     }
     // first Path Expression is mandatory
     $this->parameters[self::PARAMETER_KEY] = array();
     $this->parameters[self::PARAMETER_KEY][] = $parser->SingleValuedPathExpression();
     while ($lexer->isNextToken(Lexer::T_COMMA)) {
         $parser->match(Lexer::T_COMMA);
         $this->parameters[self::PARAMETER_KEY][] = $parser->StringPrimary();
     }
     if ($lexer->isNextToken(Lexer::T_ORDER)) {
         $this->parameters[self::ORDER_KEY] = $parser->OrderByClause();
     }
     if ($lexer->isNextToken(Lexer::T_IDENTIFIER)) {
         if (strtolower($lexer->lookahead['value']) !== 'separator') {
             $parser->syntaxError('separator');
         }
         $parser->match(Lexer::T_IDENTIFIER);
         $this->parameters[self::SEPARATOR_KEY] = $parser->StringPrimary();
     }
     $parser->match(Lexer::T_CLOSE_PARENTHESIS);
 }