Problems with QtXQuery in qt 5.12.8 - c++

Question

I am trying to read xml tags from a document using QtXQuery. Works out fine besides a '\n'-char that is attached to each query-result. Moreover using the last()-statement on a collection returns the expected number of items in the collection with a trailing repetition + '\n'.
Why QXmlQuery seem to add a ` \n` to results? (and how to solve it?) suggest to use a QStringList and only take the first item into account, yet this does not seem to work with my setup as using a QStringList on query.evaluateTo(&qsl) fails to return any results. So: my question is if this is a bug in libqt5xmlPatterns5 or if my implementation is the reason for this behavior? Am I missing some details on how to use QtXmlQuery?
So here is the piece of code:
get_tag_value:
static lib_int_err_t get_tag_value(QString *result, QUrl schema_file, QString xml_file_name, QString var_name, QString query_str)
{
lib_int_err_t ret_code = LIE_OK;
QFile *xml_f= new QFile(xml_file_name);
xml_f->open(QIODevice::ReadOnly);
if(result!=nullptr){
result->clear();
QXmlSchema xmlschema;
// QStringList *results = new QStringList();
xmlschema.load(schema_file);
QXmlQuery query(QXmlQuery::XQuery10, xmlschema.namePool());
query.bindVariable(var_name, xml_f);
query.setQuery(query_str);
query.evaluateTo(result);
// result->append(results->first());
ret_code = LIE_OK;
}
else{
ret_code = LIE_XML_MALFORMED;
}
xml_f->close();
return ret_code;
}
The input query string:
'declare copy-namespaces no-preserve, inherit; declare variable $" + var_name + " external; doc($" + var_name + ")" + "//procLib/last()" '
The schema used for data description:
<xs:element name="toolConfig">
<xs:complexType>
<xs:sequence>
<xs:element name="processingLibsSettings">
<xs:complexType>
<xs:sequence>
<xs:element name="interfaceSchemaDef" type="xs:string" minOccurs="1" maxOccurs="1"/>
<xs:element name="interfaceSchemaPath" type="xs:string" minOccurs="1" maxOccurs="1"/>
<xs:element name="processingLibsInstances">
<xs:complexType>
<xs:sequence maxOccurs="unbounded">
<xs:element name="procLib" minOccurs="0">
<xs:complexType>
<xs:sequence>
<xs:element name="procLibConfigName" type="xs:string"/>
<xs:element name="procLibConfigPath" type="xs:string"/>
<xs:element name="procLibName" type="xs:string"/>
<xs:element name="procLibPath" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="installDir" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:element>

Answer 1

Solved this with a workaround:
results=results.remove('\n');
results=results.split(' ')[0];
not really nice, but it works...