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diff --git a/moses/src/LanguageModelJoint.h b/moses/src/LanguageModelJoint.h
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+// $Id: LanguageModelJoint.h 1897 2008-10-08 23:51:26Z hieuhoang1972 $
+
+/***********************************************************************
+Moses - factored phrase-based language decoder
+Copyright (C) 2006 University of Edinburgh
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+***********************************************************************/
+
+#pragma once
+
+#include <vector>
+#include <string>
+#include <sstream>
+#include "LanguageModelSingleFactor.h"
+#include "LanguageModelMultiFactor.h"
+#include "Word.h"
+#include "FactorTypeSet.h"
+#include "FactorCollection.h"
+
+namespace Moses
+{
+
+class Phrase;
+class FactorCollection;
+
+/** LM of multiple factors. A simple extension of single factor LM - factors backoff together.
+ *	Rather slow as this uses string concatenation/split
+*/
+class LanguageModelJoint : public LanguageModelMultiFactor
+{
+protected:
+	LanguageModelSingleFactor *m_lmImpl;
+	std::vector<FactorType> m_factorTypesOrdered;
+	
+	size_t m_implFactor;
+public:
+	LanguageModelJoint(LanguageModelSingleFactor *lmImpl, bool registerScore, ScoreIndexManager &scoreIndexManager)
+	:LanguageModelMultiFactor(registerScore, scoreIndexManager)
+	{
+		m_lmImpl = lmImpl;
+	}
+	
+	~LanguageModelJoint()
+	{
+		delete m_lmImpl;
+	}
+	
+	bool Load(const std::string &filePath
+					, const std::vector<FactorType> &factorTypes
+					, float weight
+					, size_t nGramOrder)
+	{
+		m_factorTypes				= FactorMask(factorTypes);
+		m_weight 						= weight;
+		m_filePath 					= filePath;
+		m_nGramOrder 				= nGramOrder;
+	
+		m_factorTypesOrdered= factorTypes;
+		m_implFactor				= 0;
+		
+		FactorCollection &factorCollection = FactorCollection::Instance();
+
+		// sentence markers
+		for (size_t index = 0 ; index < factorTypes.size() ; ++index)
+		{
+			FactorType factorType = factorTypes[index];
+			m_sentenceStartArray[factorType] 	= factorCollection.AddFactor(Output, factorType, BOS_);
+			m_sentenceEndArray[factorType] 		= factorCollection.AddFactor(Output, factorType, EOS_);
+		}
+	
+		return m_lmImpl->Load(filePath, m_implFactor, weight, nGramOrder);
+	}
+	
+	float GetValue(const std::vector<const Word*> &contextFactor, State* finalState = NULL, unsigned int* len = NULL) const
+	{
+		if (contextFactor.size() == 0)
+		{
+			return 0;
+		}
+
+		// joint context for internal LM
+		std::vector<const Word*> jointContext;
+		
+		for (size_t currPos = 0 ; currPos < m_nGramOrder ; ++currPos )
+		{
+			const Word &word = *contextFactor[currPos];
+
+			// add word to chunked context
+			std::stringstream stream("");
+
+			const Factor *factor = word[ m_factorTypesOrdered[0] ];
+			stream << factor->GetString();
+
+			for (size_t index = 1 ; index < m_factorTypesOrdered.size() ; ++index)
+			{
+				FactorType factorType = m_factorTypesOrdered[index];
+				const Factor *factor = word[factorType];
+				stream << "|" << factor->GetString();
+			}
+			
+			factor = FactorCollection::Instance().AddFactor(Output, m_implFactor, stream.str());
+
+			Word* jointWord = new Word;
+			jointWord->SetFactor(m_implFactor, factor);
+			jointContext.push_back(jointWord);
+		}
+	
+		// calc score on chunked phrase
+		float ret = m_lmImpl->GetValue(jointContext, finalState, len);
+
+		RemoveAllInColl(jointContext);
+		
+		return ret;
+	}
+	
+};
+
+}