Error: If-expression branches must have similar types, but were int and string

[Roger L Costello]

Hi Folks,

I have a one-byte binary input file. If the input is 0 then I want the XML 
output to be "No Signal". If the input is 1 then I want the output to be 
"Green". If the input is 2 then I want the output to be "Yellow". If the input 
if 3 then I want the output to be "Red". For all other inputs, generate an 
error.

<xs:sequence dfdl:hiddenGroupRef="raw_Signal" />
<xs:element name='Signal' type='xs:string' dfdl:inputValueCalc='{
    if (../binary_Signal eq 0) then "No Signal"
    else if (../binary_Signal eq 1) then "Green"
    else if (../binary_Signal eq 2) then "Yellow"
    else if (../binary_Signal eq 3) then "Red"
    else "Error"
    }' />

<xs:group name="raw_Signal"> 
    <xs:sequence>
        <xs:element name="binary_Signal" type="unsignedint2" 
dfdl:outputValueCalc='{
            if (../Signal eq "No Signal") then 0
            else if (../Signal eq "Green") then 1
            else if (../Signal eq "Yellow") then 2
            else if (../Signal eq "Red") then 3
            else "daf:error()"
            }' />
    </xs:sequence>
</xs:group>

That results in Daffodil generating this error message:

Error: If-expression branches must have similar types, but were int and string

What am I doing wrong? Below is the entire DFDL schema.  /Roger

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"; 
           xmlns:dfdl="http://www.ogf.org/dfdl/dfdl-1.0/";
           xmlns:fn="http://www.w3.org/2005/xpath-functions";>

    <xs:annotation>
        <xs:appinfo source="http://www.ogf.org/dfdl/";>
            <dfdl:format 
                alignment="1"
                alignmentUnits="bits"  
                binaryFloatRep="ieee"
                binaryNumberRep="binary"   
                bitOrder="leastSignificantBitFirst"
                byteOrder="littleEndian"   
                calendarPatternKind="implicit"
                choiceLengthKind="implicit"
                documentFinalTerminatorCanBeMissing="yes"  
                emptyValueDelimiterPolicy="none" 
                encoding="ISO-8859-1" 
                encodingErrorPolicy="replace" 
                escapeSchemeRef="" 
                fillByte="f" 
                floating="no" 
                ignoreCase="no" 
                initiatedContent="no" 
                initiator="" 
                leadingSkip="0" 
                lengthKind="implicit"
                lengthUnits="bits"  
                nilKind="literalValue" 
                nilValueDelimiterPolicy="none" 
                occursCountKind="implicit"
                outputNewLine="%CR;%LF;"
                representation="binary"
                separator="" 
                separatorPosition="infix" 
                separatorSuppressionPolicy="anyEmpty"
                sequenceKind="ordered" 
                textStandardZeroRep="0" 
                textStandardDecimalSeparator="."
                textStandardInfinityRep="Inf" 
                textStandardExponentRep="E" 
                textStandardNaNRep="NaN" 
                textNumberPattern="#,##0.###;-#,##0.###" 
                textNumberRounding="explicit" 
                textNumberRoundingMode="roundUnnecessary" 
                textNumberRoundingIncrement="0" 
                textStandardGroupingSeparator="," 
                terminator="" 
                textBidi="no" 
                textNumberCheckPolicy="strict" 
                textNumberRep="standard" 
                textOutputMinLength="0" 
                textPadKind="none" 
                textStandardBase="10" 
                textTrimKind="none" 
                trailingSkip="0" 
                truncateSpecifiedLengthString="no" 
                utf16Width="fixed"/>
        </xs:appinfo>
    </xs:annotation>

    <xs:element name="Test">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="Segment">
                    <xs:complexType>
                        <xs:sequence>
                            <xs:sequence dfdl:hiddenGroupRef="raw_Signal" />
                            <xs:element name='Signal' type='xs:string' 
dfdl:inputValueCalc='{
                                if (../binary_Signal eq 0) then "No Signal"
                                else if (../binary_Signal eq 1) then "Green"
                                else if (../binary_Signal eq 2) then "Yellow"
                                else if (../binary_Signal eq 3) then "Red"
                                else "Error"
                                }' />
                        </xs:sequence>
                    </xs:complexType>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
    
    <xs:group name="raw_Signal"> 
        <xs:sequence>
            <xs:element name="binary_Signal" type="unsignedint2" 
dfdl:outputValueCalc='{
                if (../Signal eq "No Signal") then 0
                else if (../Signal eq "Green") then 1
                else if (../Signal eq "Yellow") then 2
                else if (../Signal eq "Red") then 3
                else "daf:error()"
                }' />
        </xs:sequence>
    </xs:group>
    
    <xs:simpleType name="unsignedint2" dfdl:length="2" 
dfdl:lengthKind="explicit">
        <xs:restriction base="xs:unsignedInt"/>
    </xs:simpleType>

</xs:schema>