return nil, errIncorrectSQLFunctionArgumentType(err)
	}

	// Assemble other arguments
	arg2, arg3 := e.From, e.For
	// Check if the second form of substring is being used
	if e.From == nil {
		arg2, arg3 = e.Arg2, e.Arg3
	}

	// Evaluate the FROM argument
	v2, err := arg2.evalNode(r, tableAlias)
	if err != nil {
		return nil, err
	}
	inferTypeForArithOp(v2)

//		clause.Associations: {"arg1"},
//		"k1":                {"arg2"},
//		"k2.k3":             {"arg3"},
//		"k4.k5.k6":          {"arg4"},
//	})
//	// preloadMap is
//	map[string]map[string][]interface{}{
//		"k0": {},
//		"k7": {
//			"k8": {},
//		},
//		"k1": {},
//		"k2": {
//			"k3": {"arg3"},
//		},
//		"k4": {
//			"k5.k6": {"arg4"},
//		},
//	}

			result.combine(e.Substring.From.analyze(s))
			if e.Substring.For != nil {
				result.combine(e.Substring.Expr.analyze(s))
			}
		case e.Substring.Arg2 != nil:
			result.combine(e.Substring.Arg2.analyze(s))
			if e.Substring.Arg3 != nil {
				result.combine(e.Substring.Arg3.analyze(s))
			}
		default:
			result.err = errVal
		}
		return result

	case sqlFnUTCNow:
		if len(e.SFunc.ArgsList) != 0 {

     * </p>
     *
     * <pre>
     * import static org.codelibs.core.log.Logger.format;
     *
     * Logger logger = Logger.getLogger(Xxx.class);
     * logger.log(format("DXXX0000", arg1, arg2, arg3));
     * </pre>
     *
     * @param logMessage
     *            ログメッセージ。{@literal null}であってはいけません
     */
    public void log(final LogMessage logMessage) {

                                                            arg0="${f:h(q)}" arg1="${f:h(allRecordCount)}"
                                                            arg2="${f:h(currentStartRecordNumber)}"
                                                            arg3="${f:h(currentEndRecordNumber)}"/>

					arg0="${displayQuery}" arg1="${fe:formatNumber(allRecordCount,'###,###')}"
					arg2="${f:h(currentStartRecordNumber)}"
					arg3="${f:h(currentEndRecordNumber)}" />
			</c:if><c:if test="${allRecordCountRelation!='EQUAL_TO'}">
				<la:message key="labels.search_result_status_over"
					arg0="${displayQuery}" arg1="${fe:formatNumber(allRecordCount,'###,###')}"
					arg2="${f:h(currentStartRecordNumber)}"

					arg0="${displayQuery}" arg1="${fe:formatNumber(allRecordCount,'###,###')}"
					arg2="${f:h(currentStartRecordNumber)}"
					arg3="${f:h(currentEndRecordNumber)}" />
			</c:if><c:if test="${allRecordCountRelation!='EQUAL_TO'}">
				<la:message key="labels.search_result_status_over"
					arg0="${displayQuery}" arg1="${fe:formatNumber(allRecordCount,'###,###')}"
					arg2="${f:h(currentStartRecordNumber)}"

	//export MyFunction
	func MyFunction(arg1, arg2 int, arg3 string) int64 {...}

	//export MyFunction2
	func MyFunction2(arg1, arg2 int, arg3 string) (int64, *C.char) {...}

They will be available in the C code as:

	extern GoInt64 MyFunction(int arg1, int arg2, GoString arg3);
	extern struct MyFunction2_return MyFunction2(int arg1, int arg2, GoString arg3);

type SubstringFunc struct {
	Expr *PrimaryTerm `parser:" \"SUBSTRING\" \"(\" @@ "`
	From *Operand     `parser:" ( \"FROM\" @@ "`
	For  *Operand     `parser:"   (\"FOR\" @@)? \")\" "`
	Arg2 *Operand     `parser:" | \",\" @@ "`
	Arg3 *Operand     `parser:"   (\",\" @@)? \")\" )"`
}

// ExtractFunc represents EXTRACT sql function
type ExtractFunc struct {

type ReaderArgs struct {
	ContentType string `xml:"Type"`
	unmarshaled bool
}

// IsEmpty - returns whether reader args is empty or not.
func (args *ReaderArgs) IsEmpty() bool {
	return !args.unmarshaled
}

// UnmarshalXML - decodes XML data.
func (args *ReaderArgs) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
	// Make subtype to avoid recursive UnmarshalXML().
	type subReaderArgs ReaderArgs