More work on lua datamodel

6 files changed, 130 insertions, 131 deletions

diff --git a/src/uscxml/Interpreter.cpp b/src/uscxml/Interpreter.cpp
index 5a1df44..8767242 100644
--- a/src/uscxml/Interpreter.cpp
+++ b/src/uscxml/Interpreter.cpp
@@ -2347,7 +2347,7 @@ bool InterpreterImpl::isInitial(const Arabica::DOM::Element<std::string>& state)
 
 	if (isParallel(parent))
 		return true;
-	
+
 	return false;
 }
 
diff --git a/src/uscxml/UUID.cpp b/src/uscxml/UUID.cpp
index b56b727..ae103ed 100644
--- a/src/uscxml/UUID.cpp
+++ b/src/uscxml/UUID.cpp
@@ -34,31 +34,31 @@ std::string UUID::getUUID() {
 bool UUID::isUUID(const std::string& uuid) {
 	if (uuid.size() != 36)
 		return false;
-	
+
 	if (uuid[8] != '-' || uuid[13] != '-' || uuid[18] != '-' || uuid[23] != '-')
 		return false;
-	
+
 	for (int i = 0; i < 36; i++) {
 		if (i == 8 || i == 13 || i == 18 || i ==23)
 			continue;
-		
+
 		char c = uuid[i];
 		if (c == 'a' ||
-				c == 'b' ||
-				c == 'c' ||
-				c == 'd' ||
-				c == 'e' ||
-				c == 'f' ||
-				c == '0' ||
-				c == '1' ||
-				c == '2' ||
-				c == '3' ||
-				c == '4' ||
-				c == '5' ||
-				c == '6' ||
-				c == '7' ||
-				c == '8' ||
-				c == '9') {
+		        c == 'b' ||
+		        c == 'c' ||
+		        c == 'd' ||
+		        c == 'e' ||
+		        c == 'f' ||
+		        c == '0' ||
+		        c == '1' ||
+		        c == '2' ||
+		        c == '3' ||
+		        c == '4' ||
+		        c == '5' ||
+		        c == '6' ||
+		        c == '7' ||
+		        c == '8' ||
+		        c == '9') {
 			continue;
 		} else {
 			return false;
diff --git a/src/uscxml/debug/SCXMLDotWriter.cpp b/src/uscxml/debug/SCXMLDotWriter.cpp
index 88db575..16269a9 100644
--- a/src/uscxml/debug/SCXMLDotWriter.cpp
+++ b/src/uscxml/debug/SCXMLDotWriter.cpp
@@ -28,7 +28,7 @@ namespace uscxml {
 
 using namespace Arabica::DOM;
 using namespace Arabica::XPath;
-	
+
 SCXMLDotWriter::SCXMLDotWriter() {
 	_iteration = 0;
 	_indentation = 0;
@@ -56,7 +56,7 @@ SCXMLDotWriter::SCXMLDotWriter(Interpreter interpreter,
 			anchIter->element = _scxml;
 		if (anchIter->childDepth >= 0 && anchIter->transDepth == -1)
 			anchIter->transDepth = anchIter->childDepth;
-		
+
 		_portType = anchIter->type;
 		assembleGraph(anchIter->element, anchIter->childDepth, anchIter->transDepth + 1);
 	}
@@ -121,7 +121,7 @@ void SCXMLDotWriter::writeTo(std::ostream& os) {
 			if (_histories.find(edgeIter->to)->second.from == _histories.find(edgeIter->to)->second.to)
 				continue;
 		}
-		
+
 		os << getPrefix() << "\"" << edgeIter->from << "\"";
 		if (edgeIter->fromPort.size() > 0) {
 			os << std::string(":\"") + edgeIter->fromPort + "\":e";
@@ -129,7 +129,7 @@ void SCXMLDotWriter::writeTo(std::ostream& os) {
 			os << ":__name";
 		}
 		os << " -> ";
-		
+
 		if (_histories.find(edgeIter->to) != _histories.end()) {
 			os << getPrefix() << "\"" << _histories.find(edgeIter->to)->second.to << "\"";
 			if (_histories.find(edgeIter->to)->second.toPort.size() > 0) {
@@ -153,11 +153,11 @@ void SCXMLDotWriter::writeTo(std::ostream& os) {
 			os << " [color=\"black\"]";
 		}
 		os << std::endl;
-		
+
 	}
-	
+
 	_indentation--;
-	
+
 	os << "}" << std::endl;
 
 }
@@ -191,7 +191,7 @@ void SCXMLDotWriter::assembleGraph(const Element<std::string>& state, int32_t ch
 	_graph[nodeId].node = state;
 	_graph[nodeId].portType = _portType;
 
-	
+
 	if (childDepth == 0 && transDepth == 0) {
 		_graph[nodeId].isBorder = true;
 	}
@@ -250,7 +250,7 @@ void SCXMLDotWriter::assembleGraph(const Element<std::string>& state, int32_t ch
 	}
 }
 
-	
+
 /**
  * Walk the complete graph and draw reachable subset
  */
@@ -263,11 +263,11 @@ void SCXMLDotWriter::writeStateElement(std::ostream& os, const Element<std::stri
 
 	std::list<Node<std::string> > invisParents;
 	bool isVisible = (_graph.find(stateId) != _graph.end());
-	
+
 	bool subgraph = InterpreterImpl::isCompound(stateElem) || InterpreterImpl::isParallel(stateElem);
 	bool fatherIsParallel = (stateElem.getParentNode() &&
-													 stateElem.getParentNode().getNodeType() == Node_base::ELEMENT_NODE &&
-													 InterpreterImpl::isParallel(Element<std::string>(stateElem.getParentNode())));
+	                         stateElem.getParentNode().getNodeType() == Node_base::ELEMENT_NODE &&
+	                         InterpreterImpl::isParallel(Element<std::string>(stateElem.getParentNode())));
 
 	if (subgraph) {
 		_indentation++;
@@ -282,13 +282,13 @@ void SCXMLDotWriter::writeStateElement(std::ostream& os, const Element<std::stri
 		os << getPrefix() << (fatherIsParallel ? "style=dashed" : "style=solid") << std::endl;
 
 		//		os << getPrefix() << "ranksep=\"equally\"" << std::endl;
-		
+
 	}
 
 	if (isVisible) {
 		// this state is visible!
 		const DotState& dotState = _graph.find(stateId)->second;
-		
+
 		// is this a subgraph?
 
 		os << std::endl;
@@ -321,32 +321,32 @@ void SCXMLDotWriter::writeStateElement(std::ostream& os, const Element<std::stri
 
 		// is the state initial?
 		bool isInitial = _interpreter.getImpl()->isInitial(stateElem);
-	//	if (isInitial)
-	//		os << getPrefix() << "style=filled, fillcolor=lightgrey, " << std::endl;
+		//	if (isInitial)
+		//		os << getPrefix() << "style=filled, fillcolor=lightgrey, " << std::endl;
 
 		DotState::mmap_s_e_t::const_iterator destIterF, destIterB;
 		std::list<std::string> outPorts; // count unique keys
 
 		switch (dotState.portType) {
-			case PORT_TARGET: // outports are per target
-				for(DotState::mmap_s_e_t::const_iterator it = dotState.targets.begin(), end = dotState.targets.end();
-						it != end;
-						it = dotState.targets.upper_bound(it->first)) {
-					outPorts.push_back(it->first);
-				}
-				break;
-			case PORT_EVENT: // outports are per event
-				for(DotState::mmap_s_e_t::const_iterator it = dotState.events.begin(), end = dotState.events.end();
-						it != end;
-						it = dotState.events.upper_bound(it->first)) {
-					outPorts.push_back(it->first);
-				}
-				break;
-			case PORT_TRANSITION:
-				for (int i = 0; i < dotState.transitions.size(); i++) {
-					outPorts.push_back(idForNode(dotState.transitions[i]));
-				}
-				break;
+		case PORT_TARGET: // outports are per target
+			for(DotState::mmap_s_e_t::const_iterator it = dotState.targets.begin(), end = dotState.targets.end();
+			        it != end;
+			        it = dotState.targets.upper_bound(it->first)) {
+				outPorts.push_back(it->first);
+			}
+			break;
+		case PORT_EVENT: // outports are per event
+			for(DotState::mmap_s_e_t::const_iterator it = dotState.events.begin(), end = dotState.events.end();
+			        it != end;
+			        it = dotState.events.upper_bound(it->first)) {
+				outPorts.push_back(it->first);
+			}
+			break;
+		case PORT_TRANSITION:
+			for (int i = 0; i < dotState.transitions.size(); i++) {
+				outPorts.push_back(idForNode(dotState.transitions[i]));
+			}
+			break;
 		}
 
 		os << getPrefix() << "label = < " << std::endl;
@@ -366,17 +366,17 @@ void SCXMLDotWriter::writeStateElement(std::ostream& os, const Element<std::stri
 		os << "  <tr><td port=\"__name\" rowspan=\"" << outPorts.size() + 1 << "\"><b>" << nameForNode(stateElem) << "</b></td></tr>" << std::endl;
 
 		switch (dotState.portType) {
-			case PORT_TARGET: // outports are per target
-				writePerTargetPorts(os, outPorts, dotState);
-				break;
-			case PORT_EVENT: // outports are per event
-				writePerEventPorts(os, outPorts, dotState);
-				break;
-			case PORT_TRANSITION:
-				writePerTransitionPorts(os, outPorts, dotState);
-				break;
+		case PORT_TARGET: // outports are per target
+			writePerTargetPorts(os, outPorts, dotState);
+			break;
+		case PORT_EVENT: // outports are per event
+			writePerEventPorts(os, outPorts, dotState);
+			break;
+		case PORT_TRANSITION:
+			writePerTransitionPorts(os, outPorts, dotState);
+			break;
 		}
-		
+
 
 		// write details of the state
 		if (details.size() > 0) {
@@ -445,12 +445,12 @@ void SCXMLDotWriter::writePerTargetPorts(std::ostream& os, const std::list<std::
 	DotState::mmap_s_e_t::const_iterator destIterF, destIterB;
 
 	for(std::list<std::string>::const_iterator nameIter = outPorts.begin(); nameIter != outPorts.end(); nameIter++) {
-		
+
 		// gather all events that activate the transition
 		std::string portName = *nameIter;
 		DotEdge edge(stateId, portName);
 		edge.fromPort = portName;
-		
+
 		std::multimap<std::string, std::string> eventConds; // event to condition
 		std::pair <DotState::mmap_s_e_t::const_iterator, DotState::mmap_s_e_t::const_iterator> targetKeyRange = dotState.targets.equal_range(portName);
 		for (destIterB = targetKeyRange.first;  destIterB != targetKeyRange.second;  ++destIterB) {
@@ -467,11 +467,11 @@ void SCXMLDotWriter::writePerTargetPorts(std::ostream& os, const std::list<std::
 		}
 		if (_graph.find(portName) != _graph.end())
 			_edges.insert(edge);
-		
+
 		typedef std::multimap<std::string, std::string>::iterator condIter_t;
 		std::stringstream outPortSS;
 		outPortSS << "<b>" << portName << "</b><br align=\"right\" />";
-		
+
 		std::string opener = "{";
 		std::string closer;
 		std::string seperator;
@@ -479,19 +479,19 @@ void SCXMLDotWriter::writePerTargetPorts(std::ostream& os, const std::list<std::
 		for(iterA = eventConds.begin(); iterA != eventConds.end(); iterA = iterB) {
 			std::string eventName = iterA->first;
 			bool hasCondition = false;
-			
+
 			std::pair <condIter_t, condIter_t> condRange = eventConds.equal_range(eventName);
 			for (iterB = condRange.first;  iterB != condRange.second;  ++iterB) {
 				hasCondition = true;
 			}
-			
+
 			outPortSS << opener << seperator << eventName << (hasCondition ? "" : "");
 			seperator = ", ";
 			opener = "";
 			closer = "}";
 		}
 		outPortSS << closer;
-		
+
 		os << "  <tr><td port=\"" << portEscape(portName) << "\" align=\"right\">" << outPortSS.str() << "</td></tr>" << std::endl;
 
 	}
@@ -582,7 +582,7 @@ std::string SCXMLDotWriter::getDetailedLabel(const Element<std::string>& elem, i
 			if (HAS_ATTR(childElems.item(i), "event "))
 				details.name += "<br />event = " + ATTR(childElems.item(i), "event");
 		}
-		
+
 		// send ---------
 		if (iequals(TAGNAME(childElems.item(i)), "send")) {
 			if (HAS_ATTR(childElems.item(i), "id"))
@@ -718,7 +718,7 @@ std::string SCXMLDotWriter::nameForNode(const Node<std::string>& node) {
 	std::string elemName;
 	if (node.getNodeType() == Node_base::ELEMENT_NODE) {
 		Element<std::string> elem = (Element<std::string>)node;
-		
+
 		if (false) {
 		} else if (elem.getTagName() == "scxml") {
 			if (elem.hasAttribute("name") && !UUID::isUUID(elem.getAttribute("name"))) {
diff --git a/src/uscxml/debug/SCXMLDotWriter.h b/src/uscxml/debug/SCXMLDotWriter.h
index 79ea6c1..3ac697f 100644
--- a/src/uscxml/debug/SCXMLDotWriter.h
+++ b/src/uscxml/debug/SCXMLDotWriter.h
@@ -68,9 +68,9 @@ public:
 		Arabica::DOM::Element<std::string> element;
 		int32_t childDepth;
 		int32_t transDepth;
-		
+
 		PortType type;
-		
+
 		operator bool() const {
 			return childDepth != -1 || transDepth != -1 || element;
 		}
@@ -94,7 +94,7 @@ public:
 
 		std::set<std::string> childs;
 		std::set<std::string> initialchilds;
-		
+
 		typedef std::multimap<std::string, Arabica::DOM::Element<std::string> > mmap_s_e_t;
 	};
 
@@ -108,7 +108,7 @@ public:
 		DotEdge() : type(EDGE_TRANSIION) {}
 		DotEdge(const std::string& from, const std::string& to) : type(EDGE_TRANSIION), from(from), to(to) {
 		}
-		
+
 		bool operator< (const DotEdge& other) const {
 			return from + fromPort + to + toPort > other.from + other.fromPort + other.to + other.toPort;
 		}
@@ -121,7 +121,7 @@ public:
 		std::string toPort;
 		std::string toCompass;
 	};
-	
+
 	SCXMLDotWriter();
 	~SCXMLDotWriter();
 
@@ -162,14 +162,14 @@ protected:
 	               const Arabica::DOM::Element<std::string>& transition);
 
 	void assembleGraph(const Arabica::DOM::Element<std::string>& start,
-										 int32_t childDepth = std::numeric_limits<int32_t>::max(),
-										 int32_t transDepth = std::numeric_limits<int32_t>::max());
+	                   int32_t childDepth = std::numeric_limits<int32_t>::max(),
+	                   int32_t transDepth = std::numeric_limits<int32_t>::max());
 	void writeStateElement(std::ostream& os, const Arabica::DOM::Element<std::string>& state);
-	
+
 	void writePerTransitionPorts(std::ostream& os, const std::list<std::string>& outPorts, const DotState& dotState);
 	void writePerEventPorts(std::ostream& os, const std::list<std::string>& outPorts, const DotState& dotState);
 	void writePerTargetPorts(std::ostream& os, const std::list<std::string>& outPorts, const DotState& dotState);
-	
+
 	void writeUnknownNode(std::ostream& os, const std::string& targetId);
 
 	int _iteration;
@@ -179,7 +179,7 @@ protected:
 
 	std::map<std::string, DotState> _graph;
 	std::set<DotEdge> _edges;
-	
+
 	// these are only set in ephemeral instances per monitor call
 	Arabica::DOM::Element<std::string> _transition;
 	Arabica::DOM::Element<std::string> _scxml;
@@ -187,7 +187,7 @@ protected:
 	std::string _xmlNSPrefix;
 	std::list<StateAnchor> _anchors;
 	std::map<std::string, DotEdge> _histories;
-	
+
 	PortType _portType;
 
 };
diff --git a/src/uscxml/plugins/datamodel/lua/LuaDataModel.cpp b/src/uscxml/plugins/datamodel/lua/LuaDataModel.cpp
index 84833fb..018a8c4 100644
--- a/src/uscxml/plugins/datamodel/lua/LuaDataModel.cpp
+++ b/src/uscxml/plugins/datamodel/lua/LuaDataModel.cpp
@@ -48,6 +48,10 @@ LuaDataModel::LuaDataModel() {
 	_luaState = NULL;
 }
 
+static int luaInspect(lua_State * l) {
+	return 0;
+}
+
 static int luaInFunction(lua_State * l) {
 	luabridge::LuaRef ref = luabridge::getGlobal(l, "__interpreter");
 	InterpreterImpl* interpreter = ref.cast<InterpreterImpl*>();
@@ -151,6 +155,7 @@ static luabridge::LuaRef getDataAsLua(lua_State* _luaState, const Data& data) {
 			luaData[compoundIter->first] = getDataAsLua(_luaState, compoundIter->second);
 			compoundIter++;
 		}
+		luaData["inspect"] = luaInspect;
 		return luaData;
 	}
 	if (data.array.size() > 0) {
@@ -161,6 +166,7 @@ static luabridge::LuaRef getDataAsLua(lua_State* _luaState, const Data& data) {
 			luaData[index++] = getDataAsLua(_luaState, *arrayIter);
 			arrayIter++;
 		}
+		luaData["inspect"] = luaInspect;
 		return luaData;
 	}
 	if (data.atom.size() > 0) {
@@ -170,7 +176,15 @@ static luabridge::LuaRef getDataAsLua(lua_State* _luaState, const Data& data) {
 			break;
 		}
 		case Data::INTERPRETED: {
-			luaData = data.atom; // not sure
+			if (isNumeric(data.atom.c_str(), 10)) {
+				if (data.atom.find(".") != std::string::npos) {
+					luaData = strTo<double>(data.atom);
+				} else {
+					luaData = strTo<long>(data.atom);
+				}
+			} else {
+				luaData = data.atom;
+			}
 		}
 		}
 		return luaData;
@@ -190,6 +204,7 @@ void LuaDataModel::setEvent(const Event& event) {
 	luaEvent["content"] = event.content;
 	luaEvent["invokeId"] = event.invokeid;
 	luaEvent["sendId"] = event.sendid;
+	luaEvent["inspect"] = luaInspect;
 
 	switch (event.eventType) {
 	case Event::INTERNAL:
@@ -214,7 +229,15 @@ void LuaDataModel::setEvent(const Event& event) {
 		if (!json.empty()) {
 			luaEvent["data"] = getDataAsLua(_luaState, json);
 		} else {
-			luaEvent["data"] = InterpreterImpl::spaceNormalize(event.content);
+			// test179
+			std::string trimmed = boost::trim_copy(event.content);
+			if ((boost::starts_with(trimmed, "'") && boost::ends_with(trimmed, "'")) ||
+			        (boost::starts_with(trimmed, "\"") && boost::ends_with(trimmed, "\""))) {
+				luaEvent["data"] = InterpreterImpl::spaceNormalize(event.content);
+			} else {
+				Data tmp(event.content, Data::INTERPRETED);
+				luaEvent["data"] = getDataAsLua(_luaState, tmp);
+			}
 		}
 	} else {
 		// _event.data is KVP
@@ -254,15 +277,11 @@ Data LuaDataModel::getStringAsData(const std::string& content) {
 			trimmedExpr = "return(" + trimmedExpr + ");";
 		}
 
-		int preStack = lua_gettop(_luaState);
-		eval(Arabica::DOM::Element<std::string>(), trimmedExpr);
-		int postStack = lua_gettop(_luaState);
-		int retVals = postStack - preStack;
+		int retVals = luaEval(Arabica::DOM::Element<std::string>(), trimmedExpr);
 		if (retVals == 1) {
 			data = getLuaAsData(luabridge::LuaRef::fromStack(_luaState, -1));
 		}
-		postStack = lua_gettop(_luaState);
-		lua_pop(_luaState, postStack - preStack);
+		lua_pop(_luaState, retVals);
 
 	}
 	return data;
@@ -280,17 +299,11 @@ uint32_t LuaDataModel::getLength(const std::string& expr) {
 	// we need the result of the expression on the lua stack -> has to "return"!
 	std::string trimmedExpr = boost::trim_copy(expr);
 
-//  luabridge::LuaRef val = luabridge::getGlobal(_luaState, expr.c_str());
-//	std::cout << val.tostring() << std::endl;
-
 	if (!boost::starts_with(trimmedExpr, "return")) {
 		trimmedExpr = "return(#" + trimmedExpr + ")";
 	}
 
-	int preStack = lua_gettop(_luaState);
-	eval(Arabica::DOM::Element<std::string>(), trimmedExpr);
-	int postStack = lua_gettop(_luaState);
-	int retVals = postStack - preStack;
+	int retVals = luaEval(Arabica::DOM::Element<std::string>(), trimmedExpr);
 
 	if (retVals == 1 && lua_isnumber(_luaState, -1)) {
 		int result = lua_tointeger(_luaState, -1);
@@ -311,19 +324,14 @@ void LuaDataModel::setForeach(const std::string& item,
 
 	const luabridge::LuaRef& arrRef = luabridge::getGlobal(_luaState, array.c_str());
 	if (arrRef.isTable()) {
-		int preStack = lua_gettop(_luaState);
 
 		// trigger syntax error for invalid items
-		eval(Arabica::DOM::Element<std::string>(), "return(" + item + ");");
-		int postStack = lua_gettop(_luaState);
-		lua_pop(_luaState, postStack - preStack);
+		int retVals = luaEval(Arabica::DOM::Element<std::string>(), "return(" + item + ");");
+		lua_pop(_luaState, retVals);
 
 		const luabridge::LuaRef& val = arrRef[iteration];
 		luabridge::setGlobal(_luaState, val, item.c_str());
 
-//		luabridge::LuaRef retVal = luabridge::getGlobal(_luaState, item.c_str());
-//		std::cout << retVal.tostring() << std::endl;
-
 		if (index.length() > 0) {
 			// assign iteration element to index
 			luabridge::setGlobal(_luaState, iteration, index.c_str());
@@ -333,12 +341,20 @@ void LuaDataModel::setForeach(const std::string& item,
 
 void LuaDataModel::eval(const Arabica::DOM::Element<std::string>& scriptElem,
                         const std::string& expr) {
+	luaEval(scriptElem, expr);
+}
+
+int LuaDataModel::luaEval(const Arabica::DOM::Element<std::string>& scriptElem,
+                          const std::string& expr) {
+	int preStack = lua_gettop(_luaState);
 	int error = luaL_loadstring(_luaState, expr.c_str()) || lua_pcall(_luaState, 0, LUA_MULTRET, 0);
 	if (error) {
 		std::string errMsg = lua_tostring(_luaState, -1);
 		lua_pop(_luaState, 1);  /* pop error message from the stack */
 		ERROR_EXECUTION_THROW(errMsg);
 	}
+	int postStack = lua_gettop(_luaState);
+	return postStack - preStack;
 }
 
 bool LuaDataModel::isDeclared(const std::string& expr) {
@@ -378,10 +394,10 @@ void LuaDataModel::assign(const Arabica::DOM::Element<std::string>& assignElem,
 //	luabridge::LuaRef val = luabridge::getGlobal(_luaState, key.c_str());
 //	std::cout << val.tostring() << std::endl;
 
-	int preStack = lua_gettop(_luaState);
+	int retVals = 0;
 
 	if (HAS_ATTR(assignElem, "expr")) {
-		eval(Arabica::DOM::Element<std::string>(), key + " = " + ATTR(assignElem, "expr") + ";");
+		retVals = luaEval(Arabica::DOM::Element<std::string>(), key + " = " + ATTR(assignElem, "expr") + ";");
 	} else if (node) {
 		ERROR_EXECUTION_THROW("Cannot assign xml nodes in lua datamodel");
 	} else if (content.size() > 0) {
@@ -397,13 +413,10 @@ void LuaDataModel::assign(const Arabica::DOM::Element<std::string>& assignElem,
 //	val = luabridge::getGlobal(_luaState, key.c_str());
 //	std::cout << val.tostring() << std::endl;
 
-	int postStack = lua_gettop(_luaState);
-	int retVals = postStack - preStack;
-
 }
 
 void LuaDataModel::assign(const std::string& location, const Data& data) {
-	std::cout << "assign" << std::endl;
+	luabridge::setGlobal(_luaState, getDataAsLua(_luaState, data), location.c_str());
 }
 
 void LuaDataModel::init(const Arabica::DOM::Element<std::string>& dataElem,
@@ -413,7 +426,7 @@ void LuaDataModel::init(const Arabica::DOM::Element<std::string>& dataElem,
 }
 
 void LuaDataModel::init(const std::string& location, const Data& data) {
-	std::cout << "init" << std::endl;
+	assign(location, data);
 }
 
 /**
@@ -429,10 +442,7 @@ bool LuaDataModel::evalAsBool(const Arabica::DOM::Node<std::string>& node, const
 		trimmedExpr = "return(" + trimmedExpr + ");";
 	}
 
-	int preStack = lua_gettop(_luaState);
-	eval(Arabica::DOM::Element<std::string>(), trimmedExpr);
-	int postStack = lua_gettop(_luaState);
-	int retVals = postStack - preStack;
+	int retVals = luaEval(Arabica::DOM::Element<std::string>(), trimmedExpr);
 
 	if (retVals == 1 && lua_isboolean(_luaState, -1)) {
 		bool result = lua_toboolean(_luaState, -1);
@@ -450,10 +460,7 @@ std::string LuaDataModel::evalAsString(const std::string& expr) {
 		trimmedExpr = "return(" + trimmedExpr + ")";
 	}
 
-	int preStack = lua_gettop(_luaState);
-	eval(Arabica::DOM::Element<std::string>(), trimmedExpr);
-	int postStack = lua_gettop(_luaState);
-	int retVals = postStack - preStack;
+	int retVals = luaEval(Arabica::DOM::Element<std::string>(), trimmedExpr);
 
 	if (retVals == 1 && lua_isstring(_luaState, -1)) {
 		std::string result = lua_tostring(_luaState, -1);
diff --git a/src/uscxml/plugins/datamodel/lua/LuaDataModel.h b/src/uscxml/plugins/datamodel/lua/LuaDataModel.h
index c5d9e4b..828db0e 100644
--- a/src/uscxml/plugins/datamodel/lua/LuaDataModel.h
+++ b/src/uscxml/plugins/datamodel/lua/LuaDataModel.h
@@ -87,16 +87,8 @@ public:
 
 protected:
 
-	static int luaEventData(lua_State * l);
-	static int luaEventOrigin(lua_State * l);
-	static int luaEventOriginType(lua_State * l);
-	static int luaEventRaw(lua_State * l);
-	static int luaEventXML(lua_State * l);
-	static int luaEventName(lua_State * l);
-	static int luaEventContent(lua_State * l);
-	static int luaEventSendId(lua_State * l);
-	static int luaEventInvokeId(lua_State * l);
-	static int luaEventDestructor(lua_State * l);
+	virtual int luaEval(const Arabica::DOM::Element<std::string>& scriptElem,
+	                    const std::string& expr);
 
 	lua_State* _luaState;
 };