Fixed the 100% CPU utilization bug and replaced the bool() cast operator for data by empty()

21 files changed, 255 insertions, 49 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3d4b2ea..909b167 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -370,21 +370,29 @@ elseif (${CMAKE_CXX_COMPILER_ID} STREQUAL "MSVC")
 	add_definitions("-D_SCL_SECURE_NO_WARNINGS")
 	add_definitions("-D_CRT_SECURE_NO_WARNINGS")
 	add_definitions("/bigobj")
-	
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /GL")
-
-	set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /LTCG")
-	set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /LTCG")
-	set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} /LTCG")
-	set(STATIC_LIBRARY_FLAGS "${STATIC_LIBRARY_FLAGS} /LTCG")
 
-	# set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /NODEFAULTLIB:LIBCMT")
-	# set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /NODEFAULTLIB:LIBCMT")
-	# set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} /NODEFAULTLIB:LIBCMT")
-	# set(STATIC_LIBRARY_FLAGS "${STATIC_LIBRARY_FLAGS} /NODEFAULTLIB:LIBCMT")
+	# set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /GL") # /LTCG is implied with /GL.
+
+	# be very clear about linking debug / non-debug C++ runtimes
+	foreach(FLAGS CMAKE_EXE_LINKER_FLAGS_RELEASE CMAKE_SHARED_LINKER_FLAGS_RELEASE CMAKE_MODULE_LINKER_FLAGS_RELEASE)
+		set(${FLAGS} "${${FLAGS}} /ignore:4099 /NODEFAULTLIB:MSVCRTD")
+	endforeach()
+
+	# use static MSVCRT
+	# foreach(FLAGS 
+	# 	CMAKE_C_FLAGS_DEBUG
+	# 	CMAKE_C_FLAGS_MINSIZEREL
+	# 	CMAKE_C_FLAGS_RELEASE
+	# 	CMAKE_C_FLAGS_RELWITHDEBINFO
+	# 	CMAKE_CXX_FLAGS_DEBUG
+	# 	CMAKE_CXX_FLAGS_MINSIZEREL
+	# 	CMAKE_CXX_FLAGS_RELEASE
+	# 	CMAKE_CXX_FLAGS_RELWITHDEBINFO)
+	# 	if(${FLAGS} MATCHES "/MD")
+	# 		string(REGEX REPLACE "/MD" "/MT" ${FLAGS} "${${FLAGS}}")
+	# 	endif()
+	# endforeach()
 	
-	# SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /NODEFAULTLIB")
-	# SET(CMAKE_EXE_LINKER_FLAGS_DEBUG "${CMAKE_EXE_LINKER_FLAGS_DEBUG} /NODEFAULTLIB:MSVCRTD.lib")
 	
 elseif (${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang")
 	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-parentheses-equality")
@@ -796,7 +804,7 @@ find_package(MILES)
 #set(JPEG_ROOT_PATH "" CACHE STRING "Where to find libjpeg")
 if (MILES_FOUND)
 
-	if (OFF)
+	if (NOT WIN32)
 		# openal is only needed for miles
 		find_package(OpenAL)
 		find_package(JPEG)
@@ -937,6 +945,7 @@ endif()
 if (NOT CMAKE_CROSSCOMPILING)
 	add_executable(uscxml-browser apps/uscxml-browser.cpp)
 	target_link_libraries(uscxml-browser uscxml)
+	
 	if (NOT CMAKE_CROSSCOMPILING)
 		set_target_properties(uscxml-browser PROPERTIES COTIRE_ADD_UNITY_BUILD FALSE)
 #		cotire(uscxml-browser)
diff --git a/contrib/local/compress_and_upload_deps.sh b/contrib/local/compress_and_upload_deps.sh
index 5a2cea3..4abb4a9 100755
--- a/contrib/local/compress_and_upload_deps.sh
+++ b/contrib/local/compress_and_upload_deps.sh
@@ -33,6 +33,7 @@ ssh ${USCXML_PREBUILT_HOST} mkdir -p ${USCXML_PREBUILT_PATH}/${VERSION}
 PLATFORMS=`find . -maxdepth 1 -type d -regex ./[^\.].*`
 #PLATFORMS="linux-x86_64"
 #PLATFORMS="darwin-i386"
+PLATFORMS="windows-x86"
 for FILE in ${PLATFORMS}; do
   PLATFORM=`basename $FILE`
   echo $FILE
diff --git a/src/uscxml/Message.cpp b/src/uscxml/Message.cpp
index 55be0e4..0a0eed0 100644
--- a/src/uscxml/Message.cpp
+++ b/src/uscxml/Message.cpp
@@ -488,7 +488,7 @@ Data Data::fromJSON(const std::string& jsonString) {
 void Event::initContent(const std::string& content) {
 	// try to parse as JSON
 	Data json = Data::fromJSON(content);
-	if (json) {
+	if (!json.empty()) {
 		data = json;
 		return;
 	}
diff --git a/src/uscxml/Message.h b/src/uscxml/Message.h
index 57e8680..27b2ac5 100644
--- a/src/uscxml/Message.h
+++ b/src/uscxml/Message.h
@@ -106,8 +106,15 @@ public:
 	explicit Data(const Arabica::DOM::Node<std::string>& dom);
 	virtual ~Data() {}
 
-	operator bool() const {
-		return (atom.length() > 0 || !compound.empty() || !array.empty() || binary || node);
+	bool empty() const {
+		bool hasContent = (atom.length() > 0 || !compound.empty() || !array.empty() || binary || node);
+		return !hasContent;
+	}
+
+	bool operator<(const Data& other) const {
+		std::string thisJSON = Data::toJSON(*this);
+		std::string otherJSON = Data::toJSON(other);
+		return (thisJSON < otherJSON);
 	}
 
 	void merge(const Data& other);
@@ -120,10 +127,18 @@ public:
 		return operator[](key.c_str());
 	}
 
+	const Data& operator[](const std::string& key) const {
+		return operator[](key.c_str());
+	}
+
 	Data& operator[](const char* key) {
 		return compound[key];
 	}
 
+	const Data& operator[](const char* key) const {
+		return compound.at(key);
+	}
+
 	Data& operator[](const size_t index) {
 		while(array.size() < index) {
 			array.push_back(Data("", Data::VERBATIM));
diff --git a/src/uscxml/debug/DebuggerServlet.cpp b/src/uscxml/debug/DebuggerServlet.cpp
index a99aaf8..17c11d6 100644
--- a/src/uscxml/debug/DebuggerServlet.cpp
+++ b/src/uscxml/debug/DebuggerServlet.cpp
@@ -24,7 +24,7 @@
 namespace uscxml {
 
 void DebuggerServlet::pushData(boost::shared_ptr<DebugSession> session, Data pushData) {
-	std::cout << "trying to push " << pushData["replyType"].atom << std::endl;
+	std::cout << "trying to push " << pushData.at("replyType").atom << std::endl;
 
 	if (!session) {
 		if (_sendQueues.size() > 0) // logging is not aware of its interpreter
@@ -44,7 +44,7 @@ void DebuggerServlet::serverPushData(boost::shared_ptr<DebugSession> session) {
 		return;
 
 	Data reply = _sendQueues[session].pop();
-	std::cout << "pushing " << reply["replyType"].atom << std::endl;
+	std::cout << "pushing " << reply.at("replyType").atom << std::endl;
 	returnData(_clientConns[session], reply);
 	_clientConns[session] = HTTPServer::Request();
 }
@@ -117,7 +117,7 @@ bool DebuggerServlet::httpRecvRequest(const HTTPServer::Request& request) {
 		replyData.compound["status"] = Data("failure", Data::VERBATIM);
 		replyData.compound["reason"] = Data("No such session", Data::VERBATIM);
 	}
-	if (replyData) {
+	if (!replyData.empty()) {
 		returnData(request, replyData);
 		return true;
 	}
@@ -165,7 +165,7 @@ bool DebuggerServlet::httpRecvRequest(const HTTPServer::Request& request) {
 		replyData = session->debugEval(request.data["content"]);
 	}
 
-	if (replyData) {
+	if (!replyData.empty()) {
 		returnData(request, replyData);
 		return true;
 	}
diff --git a/src/uscxml/interpreter/InterpreterDraft6.cpp b/src/uscxml/interpreter/InterpreterDraft6.cpp
index 8be2634..12d6123 100644
--- a/src/uscxml/interpreter/InterpreterDraft6.cpp
+++ b/src/uscxml/interpreter/InterpreterDraft6.cpp
@@ -121,7 +121,8 @@ NodeSet<std::string> InterpreterDraft6::getDocumentInitialTransitions() {
 // a macrostep
 InterpreterState InterpreterDraft6::step(bool blocking) {
 	try {
-
+		tthread::lock_guard<tthread::recursive_mutex> lock(_mutex);
+		
 		monIter_t monIter;
 		NodeSet<std::string> enabledTransitions;
 		
@@ -147,6 +148,7 @@ InterpreterState InterpreterDraft6::step(bool blocking) {
 		
 		// read an external event and react
 		if (blocking) {
+			
 			// wait until an event becomes available
 			while(_externalQueue.isEmpty()) {
 				_condVar.wait(_mutex);
diff --git a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
index a064394..a6909b5 100644
--- a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
+++ b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
@@ -222,7 +222,7 @@ void JSCDataModel::setEvent(const Event& event) {
 	} else if (event.content.length() > 0) {
 		// _event.data is a string or JSON
 		Data json = Data::fromJSON(event.content);
-		if (json) {
+		if (!json.empty()) {
 			JSStringRef propName = JSStringCreateWithUTF8CString("data");
 			JSObjectSetProperty(_ctx, eventObj, propName, getDataAsValue(json), 0, &exception);
 			JSStringRelease(propName);
@@ -255,7 +255,7 @@ void JSCDataModel::setEvent(const Event& event) {
 				nameListIter++;
 			}
 		}
-		if (eventCopy.data > 0) {
+		if (!eventCopy.data.empty()) {
 			JSStringRef propName = JSStringCreateWithUTF8CString("data");
 			JSObjectSetProperty(_ctx, eventObj, propName, getDataAsValue(eventCopy.data), 0, &exception);
 			JSStringRelease(propName);
diff --git a/src/uscxml/plugins/datamodel/ecmascript/v8/V8DataModel.cpp b/src/uscxml/plugins/datamodel/ecmascript/v8/V8DataModel.cpp
index ec9557e..2bdd796 100644
--- a/src/uscxml/plugins/datamodel/ecmascript/v8/V8DataModel.cpp
+++ b/src/uscxml/plugins/datamodel/ecmascript/v8/V8DataModel.cpp
@@ -233,7 +233,7 @@ void V8DataModel::setEvent(const Event& event) {
 	} else if (event.content.length() > 0) {
 		// _event.data is a string or JSON
 		Data json = Data::fromJSON(event.content);
-		if (json) {
+		if (!json.empty()) {
 			eventObj->Set(v8::String::New("data"), getDataAsValue(json));
 		} else {
 			eventObj->Set(v8::String::New("data"), v8::String::New(InterpreterImpl::spaceNormalize(event.content).c_str()));
@@ -255,7 +255,7 @@ void V8DataModel::setEvent(const Event& event) {
 				nameListIter++;
 			}
 		}
-		if (eventCopy.data) {
+		if (!eventCopy.data.empty()) {
 //			std::cout << Data::toJSON(eventCopy.data);
 			eventObj->Set(v8::String::New("data"), getDataAsValue(eventCopy.data)); // set data part of _event
 		} else {
diff --git a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
index 4cbe8f5..76c4373 100644
--- a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
+++ b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
@@ -276,7 +276,7 @@ void SWIDataModel::setEvent(const Event& event) {
 			PlCall(dataInitStr.str().c_str());
 		} else if (event.content.size() > 0) {
 			PlCall("assert", PlCompound("event", PlCompound("data", PlString(InterpreterImpl::spaceNormalize(event.content).c_str()))));
-		} else if (event.data) {
+		} else if (!event.data.empty()) {
 			assertFromData(event.data, "event(data(", 2);
 		}
 
@@ -817,7 +817,7 @@ void SWIDataModel::assign(const Element<std::string>& assignElem,
 					PlCall("retractall", PlCompound(predicate.c_str(), 1));
 				dataInitStr << "load_xml_file('" << domUrl.asLocalFile(".pl") << "', XML), copy_term(XML,DATA), " << callAssert << "(" << predicate << "(DATA))";
 				PlCall(dataInitStr.str().c_str());
-			} else if (json) {
+			} else if (!json.empty()) {
 				std::stringstream dataInitStr;
 				if (iequals(type, "retract"))
 					PlCall("retractall", PlCompound(predicate.c_str(), 1));
diff --git a/src/uscxml/plugins/element/file/FileElement.cpp b/src/uscxml/plugins/element/file/FileElement.cpp
index aef63aa..899c2d6 100644
--- a/src/uscxml/plugins/element/file/FileElement.cpp
+++ b/src/uscxml/plugins/element/file/FileElement.cpp
@@ -223,7 +223,7 @@ void FileElement::enterElement(const Arabica::DOM::Node<std::string>& node) {
 		case JSON: {
 			Data json = Data::fromJSON(fileContents);
 			free(fileContents);
-			if (!json) {
+			if (json.empty()) {
 				LOG(ERROR) << "Cannot parse contents of " << _filepath << " as JSON";
 				return;
 			}
diff --git a/src/uscxml/plugins/invoker/CMakeLists.txt b/src/uscxml/plugins/invoker/CMakeLists.txt
index 8ae4516..ceb9c90 100644
--- a/src/uscxml/plugins/invoker/CMakeLists.txt
+++ b/src/uscxml/plugins/invoker/CMakeLists.txt
@@ -109,7 +109,7 @@ if (EXPECT_FOUND AND TCL_FOUND)
 			invoker_expect SHARED 
 			${EXPECT_INVOKER}
 			"../Plugins.cpp")
-		target_link_libraries(invoker_expect uscxml)
+		target_link_libraries(invoker_expect uscxml ${EXPECT_LIBRARY} ${TCL_LIBRARY})
 		set_target_properties(invoker_expect PROPERTIES FOLDER "Plugin Invoker")
 	else()
 		list (APPEND USCXML_FILES ${EXPECT_INVOKER})
diff --git a/src/uscxml/plugins/invoker/ffmpeg/FFMPEGInvoker.cpp b/src/uscxml/plugins/invoker/ffmpeg/FFMPEGInvoker.cpp
index f43e406..b6203d4 100644
--- a/src/uscxml/plugins/invoker/ffmpeg/FFMPEGInvoker.cpp
+++ b/src/uscxml/plugins/invoker/ffmpeg/FFMPEGInvoker.cpp
@@ -250,7 +250,7 @@ void FFMPEGInvoker::process(const SendRequest& req) {
 
 	Data image;
 	Event::getParam(req.params, "frame", image);
-	if (!image) {
+	if (image.empty()) {
 		return;
 	}
 
diff --git a/src/uscxml/plugins/invoker/graphics/openscenegraph/converter/OSGConverter.cpp b/src/uscxml/plugins/invoker/graphics/openscenegraph/converter/OSGConverter.cpp
index bc747a1..0ebf9b8 100644
--- a/src/uscxml/plugins/invoker/graphics/openscenegraph/converter/OSGConverter.cpp
+++ b/src/uscxml/plugins/invoker/graphics/openscenegraph/converter/OSGConverter.cpp
@@ -394,7 +394,7 @@ void OSGConverter::reportSuccess(const SendRequest& req, const Data& content) {
 		event.name = "convert";
 	event.name += ".success";
 
-	if (content)
+	if (!content.empty())
 		event.data.compound["content"] = content;
 	returnEvent(event);
 }
diff --git a/src/uscxml/plugins/invoker/miles/.MilesSessionInvoker.cpp.swp b/src/uscxml/plugins/invoker/miles/.MilesSessionInvoker.cpp.swp
deleted file mode 100644
index 368f327..0000000
--- a/src/uscxml/plugins/invoker/miles/.MilesSessionInvoker.cpp.swp
+++ /dev/null
diff --git a/src/uscxml/plugins/invoker/umundo/UmundoInvoker.cpp b/src/uscxml/plugins/invoker/umundo/UmundoInvoker.cpp
index c84fd8f..6ef1bd4 100644
--- a/src/uscxml/plugins/invoker/umundo/UmundoInvoker.cpp
+++ b/src/uscxml/plugins/invoker/umundo/UmundoInvoker.cpp
@@ -77,10 +77,10 @@ void UmundoInvoker::send(const SendRequest& req) {
 	try {
 		Data data = req.data;
 
-		if (!data && req.content.length())
+		if (data.empty() && req.content.length())
 			data = _interpreter->getDataModel().getStringAsData(req.content);
 
-		if (!data) {
+		if (data.empty()) {
 			LOG(ERROR) << "Cannot transform content to data object per datamodel or no data given";
 			return;
 		}
diff --git a/src/uscxml/plugins/invoker/xhtml/XHTMLInvoker.cpp b/src/uscxml/plugins/invoker/xhtml/XHTMLInvoker.cpp
index e607cf4..0418f8a 100644
--- a/src/uscxml/plugins/invoker/xhtml/XHTMLInvoker.cpp
+++ b/src/uscxml/plugins/invoker/xhtml/XHTMLInvoker.cpp
@@ -81,7 +81,7 @@ bool XHTMLInvoker::httpRecvRequest(const HTTPServer::Request& req) {
 		} else {
 			// a POST request
 			Event ev(req);
-			if (ev.data["header"]["X-SCXML-Name"]) {
+			if (ev.data["header"].hasKey("X-SCXML-Name")) {
 				ev.name = ev.data["header"]["X-SCXML-Name"].atom;
 			} else {
 				ev.name = req.data.at("type").atom;
@@ -101,7 +101,7 @@ bool XHTMLInvoker::httpRecvRequest(const HTTPServer::Request& req) {
 	}
 
 	// initial request for a document
-	if (!req.data["query"] && // no query parameters
+	if (!req.data.hasKey("query") && // no query parameters
 	        iequals(req.data.at("type").atom, "get") && // request type is GET
 	        req.content.length() == 0) { // no content
 
@@ -113,7 +113,7 @@ bool XHTMLInvoker::httpRecvRequest(const HTTPServer::Request& req) {
 //			ss << _invokeReq.getFirstDOMElement();
 			ss << _invokeReq.dom;
 			content = ss.str();
-		} else if(_invokeReq.data) {
+		} else if(!_invokeReq.data.empty()) {
 			ss << _invokeReq.data;
 			content = ss.str();
 		} else if (_invokeReq.content.length() > 0) {
@@ -163,7 +163,7 @@ void XHTMLInvoker::send(const SendRequest& req) {
 	SendRequest reqCopy(req);
 	_interpreter->getDataModel().replaceExpressions(reqCopy.content);
 	Data json = Data::fromJSON(reqCopy.content);
-	if (json) {
+	if (!json.empty()) {
 		reqCopy.data = json;
 	}
 
@@ -195,7 +195,7 @@ void XHTMLInvoker::reply(const SendRequest& req, const HTTPServer::Request& long
 		ss << req.dom;
 		reply.content = ss.str();
 		reply.headers["Content-Type"] = "application/xml";
-	} else if (req.data) {
+	} else if (!req.data.empty()) {
 		reply.content = Data::toJSON(req.data);
 		reply.headers["Content-Type"] = "application/json";
 	} else if (req.content.length() > 0) {
diff --git a/src/uscxml/plugins/ioprocessor/basichttp/BasicHTTPIOProcessor.cpp b/src/uscxml/plugins/ioprocessor/basichttp/BasicHTTPIOProcessor.cpp
index 9c1ba45..8489d60 100644
--- a/src/uscxml/plugins/ioprocessor/basichttp/BasicHTTPIOProcessor.cpp
+++ b/src/uscxml/plugins/ioprocessor/basichttp/BasicHTTPIOProcessor.cpp
@@ -222,7 +222,7 @@ void BasicHTTPIOProcessor::send(const SendRequest& req) {
 		kvps << kvpSeperator << keyCStr << "=" << valueCStr;
 		free(valueCStr);
 		kvpSeperator = "&";
-	} else if (req.data) {
+	} else if (!req.data.empty()) {
 		char* valueCStr = NULL;
 		if (req.data.atom.length() || req.data.array.size() || req.data.compound.size()) {
 			valueCStr = evhttp_encode_uri(Data::toJSON(req.data).c_str());
diff --git a/src/uscxml/plugins/ioprocessor/comet/CometIOProcessor.cpp b/src/uscxml/plugins/ioprocessor/comet/CometIOProcessor.cpp
index 32052c7..cf11ec8 100644
--- a/src/uscxml/plugins/ioprocessor/comet/CometIOProcessor.cpp
+++ b/src/uscxml/plugins/ioprocessor/comet/CometIOProcessor.cpp
@@ -82,7 +82,7 @@ void CometIOProcessor::reply(const SendRequest& req, const HTTPServer::Request&
 		ss << req.dom;
 		reply.content = ss.str();
 		reply.headers["Content-Type"] = "application/xml";
-	} else if (req.data) {
+	} else if (!req.data.empty()) {
 		reply.content = Data::toJSON(req.data);
 		reply.headers["Content-Type"] = "application/json";
 	} else if (req.content.length() > 0) {
diff --git a/src/uscxml/server/InterpreterServlet.cpp b/src/uscxml/server/InterpreterServlet.cpp
index 303aad0..2bbb856 100644
--- a/src/uscxml/server/InterpreterServlet.cpp
+++ b/src/uscxml/server/InterpreterServlet.cpp
@@ -55,13 +55,13 @@ bool InterpreterHTTPServlet::httpRecvRequest(const HTTPServer::Request& req) {
 	event.name = "http." + event.data.compound["type"].atom;
 	event.origin = toStr((uintptr_t)req.evhttpReq);
 
-	if (event.data.compound["content"]) {
+	if (!event.data.compound["content"].empty()) {
 		if (event.data.compound["content"].compound.size() > 0) {
 			std::map<std::string, Data>::iterator compoundIter = event.data.compound["content"].compound.begin();
 			while(compoundIter != event.data.compound["content"].compound.end()) {
 //				std::cout << compoundIter->second.atom << std::endl;
 				Data json = Data::fromJSON(compoundIter->second.atom);
-				if (json) {
+				if (!json.empty()) {
 //					std::cout << Data::toJSON(json) << std::endl;
 					compoundIter->second = json;
 				}
@@ -119,12 +119,12 @@ bool InterpreterWebSocketServlet::wsRecvRequest(struct evws_connection *conn, co
 	event.name = "ws." + event.data.compound["type"].atom;
 	event.origin = toStr((uintptr_t)conn);
 
-	if (event.data.compound["type"].atom.compare("text") == 0 && event.data.compound["content"]) {
+	if (event.data.compound["type"].atom.compare("text") == 0 && !event.data.compound["content"].empty()) {
 		if (event.data.compound["content"].compound.size() > 0) {
 			std::map<std::string, Data>::iterator compoundIter = event.data.compound["content"].compound.begin();
 			while(compoundIter != event.data.compound["content"].compound.end()) {
 				Data json = Data::fromJSON(compoundIter->second.atom);
-				if (json) {
+				if (!json.empty()) {
 					compoundIter->second = json;
 				}
 				compoundIter++;
@@ -145,7 +145,7 @@ Data InterpreterWebSocketServlet::getDataModelVariables() {
 
 void InterpreterWebSocketServlet::send(const SendRequest& req) {
 
-	if (!req.data) {
+	if (req.data.empty()) {
 		LOG(WARNING) << "No content given to send on websocket!";
 		return;
 	}
@@ -166,7 +166,7 @@ void InterpreterWebSocketServlet::send(const SendRequest& req) {
 			                   EVWS_TEXT_FRAME,
 			                   data.c_str(),
 			                   data.length());
-		} else if (req.data) {
+		} else if (!req.data.empty()) {
 			std::string data = Data::toJSON(req.data);
 			HTTPServer::wsSend(_requests[req.target],
 			                   EVWS_TEXT_FRAME,
@@ -191,7 +191,7 @@ void InterpreterWebSocketServlet::send(const SendRequest& req) {
 			                        EVWS_TEXT_FRAME,
 			                        data.c_str(),
 			                        data.length());
-		} else if (req.data) {
+		} else if (!req.data.empty()) {
 			std::string data = Data::toJSON(req.data);
 			HTTPServer::wsBroadcast(req.target.c_str(),
 			                        EVWS_TEXT_FRAME,
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index f28633e..b655384 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -140,7 +140,7 @@ set_target_properties(test-datamodel PROPERTIES FOLDER "Tests")
 if (EXPECT_FOUND AND TCL_FOUND)
 	add_executable(test-expect 
 		src/test-expect.cpp)
-		target_link_libraries(test-expect uscxml)
+		target_link_libraries(test-expect uscxml ${EXPECT_LIBRARY} ${TCL_LIBRARY})
 	set_target_properties(test-expect PROPERTIES FOLDER "Tests")
 endif()
 
diff --git a/test/src/test-datamodel.cpp b/test/src/test-datamodel.cpp
index 452d2b9..58f7030 100644
--- a/test/src/test-datamodel.cpp
+++ b/test/src/test-datamodel.cpp
@@ -12,6 +12,177 @@
 using namespace uscxml;
 using namespace boost;
 
+class TestData {
+public:
+	enum Type {
+		VERBATIM,
+		INTERPRETED,
+	};
+	
+	TestData() : type(INTERPRETED) {}
+	
+	// TODO: default INTERPRETED is unfortunate
+	TestData(const std::string& atom_, Type type_ = INTERPRETED) : atom(atom_), type(type_) {}
+	TestData(const char* data, size_t size, const std::string& mimeType, bool adopt = false);
+	
+	// convenience constructors
+	TestData(short atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(int atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(unsigned int atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(long atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(unsigned long atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(float atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(double atom_) : atom(toStr(atom_)), type(INTERPRETED) {}
+	TestData(bool atom_) : type(INTERPRETED) {
+		if (atom_) {
+			atom = "true";
+		} else {
+			atom = "false";
+		}
+	}
+	
+	template <typename T> TestData(T value, Type type_) : atom(toStr(value)), type(type_) {}
+	
+#if 0
+	// constructor for arbitrary types, skip if type is subclass though (C++11)
+	// we will have to drop this constructor as it interferes with operator Data() and entails C++11
+	template <typename T>
+	Data(T value, typename std::enable_if<! std::is_base_of<Data, T>::value>::type* = nullptr)
+	: atom(toStr(value)), type(INTERPRETED) {}
+#endif
+	
+	
+	explicit TestData(const Arabica::DOM::Node<std::string>& dom);
+	virtual ~TestData() {}
+	
+	explicit operator bool() const {
+		return (atom.length() > 0 || !compound.empty() || !array.empty() || binary || node);
+	}
+		
+	bool hasKey(const std::string& key) const {
+		return (!compound.empty() && compound.find(key) != compound.end());
+	}
+	
+	TestData& operator[](const std::string& key) {
+		return operator[](key.c_str());
+	}
+	
+	TestData& operator[](const char* key) {
+		return compound[key];
+	}
+	
+	TestData& operator[](const size_t index) {
+		while(array.size() < index) {
+			array.push_back(TestData("", TestData::VERBATIM));
+		}
+		std::list<TestData>::iterator arrayIter = array.begin();
+		for (int i = 0; i < index; i++, arrayIter++) {}
+		return *arrayIter;
+	}
+	
+	const TestData at(const std::string& key) const {
+		return at(key.c_str());
+	}
+	
+	const TestData at(const char* key) const {
+		if (hasKey(key))
+			return compound.at(key);
+		TestData data;
+		return data;
+	}
+	
+	const TestData item(const size_t index) const {
+		if (array.size() < index) {
+			std::list<TestData>::const_iterator arrayIter;
+			for (int i = 0; i < index; i++, arrayIter++) {}
+			return *arrayIter;
+		}
+		TestData data;
+		return data;
+	}
+	
+	bool operator==(const TestData &other) const {
+		if (other.atom.size() != atom.size())
+			return false;
+		if (other.type != type)
+			return false;
+		if (other.binary != binary)
+			return false;
+		if (other.array.size() != array.size())
+			return false;
+		if (other.compound.size() != compound.size())
+			return false;
+		
+		if (other.atom != atom)
+			return false;
+		if (other.array != array)
+			return false;
+		if (other.compound != compound)
+			return false;
+		if (other.node != node)
+			return false;
+		
+		return true;
+	}
+	
+	bool operator!=(const TestData &other) const {
+		return !(*this == other);
+	}
+	
+	operator std::string() const {
+		return atom;
+	}
+	
+	operator std::map<std::string, TestData>() {
+		return compound;
+	}
+	
+	operator std::list<TestData>() {
+		return array;
+	}
+		
+	std::map<std::string, TestData> getCompound() {
+		return compound;
+	}
+	void setCompound(const std::map<std::string, TestData>& compound) {
+		this->compound = compound;
+	}
+	
+	std::list<TestData> getArray() {
+		return array;
+	}
+	void setArray(const std::list<TestData>& array) {
+		this->array = array;
+	}
+	
+	std::string getAtom() {
+		return atom;
+	}
+	void setAtom(const std::string& atom) {
+		this->atom = atom;
+	}
+	
+	Type getType() {
+		return type;
+	}
+	void setType(const Type type) {
+		this->type = type;
+	}
+	
+	Arabica::DOM::Node<std::string> node;
+	std::map<std::string, TestData> compound;
+	std::list<TestData> array;
+	std::string atom;
+	boost::shared_ptr<Blob> binary;
+	Type type;
+	
+};
+
+
+
+void testConstData(const TestData& data) {
+//	std::cout << data.at("foo") << std::endl;
+}
 
 int main(int argc, char** argv) {
 #ifdef _WIN32
@@ -19,6 +190,14 @@ int main(int argc, char** argv) {
 	WSAStartup(MAKEWORD(2, 2), &wsaData);
 #endif
 
+	{
+		TestData data;
+		data["foo"] = "bar";
+		testConstData(data);
+//		std::cout << data << std::endl;
+	}
+	exit(0);
+	
 	Interpreter interpreter = Interpreter::fromXML("<scxml></scxml>");
 	DataModel dm(Factory::getInstance()->createDataModel("ecmascript", interpreter.getImpl().get()));
 	dm.evalAsString("var foo = 12");