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#include "GlueRuleSynthesizer.h"
#include <sstream>
#include "moses/FF/UnknownWordPenaltyProducer.h"
#include "moses/StaticData.h"
namespace Moses
{
namespace Syntax
{
namespace T2S
{
void GlueRuleSynthesizer::SynthesizeRule(const InputTree::Node &node)
{
const Word &sourceLhs = node.pvertex.symbol;
boost::scoped_ptr<Phrase> sourceRhs(SynthesizeSourcePhrase(node));
TargetPhrase *tp = SynthesizeTargetPhrase(node, *sourceRhs);
TargetPhraseCollection::shared_ptr tpc
= GetOrCreateTargetPhraseCollection(m_ruleTrie, sourceLhs, *sourceRhs);
tpc->Add(tp);
}
Phrase *GlueRuleSynthesizer::SynthesizeSourcePhrase(const InputTree::Node &node)
{
Phrase *phrase = new Phrase(node.children.size());
for (std::vector<InputTree::Node*>::const_iterator p = node.children.begin();
p != node.children.end(); ++p) {
phrase->AddWord((*p)->pvertex.symbol);
}
/*
TODO What counts as an OOV?
phrase->AddWord() = sourceWord;
phrase->GetWord(0).SetIsOOV(true);
*/
return phrase;
}
TargetPhrase *GlueRuleSynthesizer::SynthesizeTargetPhrase(
const InputTree::Node &node, const Phrase &sourceRhs)
{
const StaticData &staticData = StaticData::Instance();
const UnknownWordPenaltyProducer &unknownWordPenaltyProducer =
UnknownWordPenaltyProducer::Instance();
TargetPhrase *targetPhrase = new TargetPhrase();
util::StringStream alignmentSS;
for (std::size_t i = 0; i < node.children.size(); ++i) {
const Word &symbol = node.children[i]->pvertex.symbol;
if (symbol.IsNonTerminal()) {
targetPhrase->AddWord(staticData.GetOutputDefaultNonTerminal());
} else {
// TODO Check this
Word &targetWord = targetPhrase->AddWord();
targetWord.CreateUnknownWord(symbol);
}
alignmentSS << i << "-" << i << " ";
}
// Assign the lowest possible score so that glue rules are only used when
// absolutely required.
float score = LOWEST_SCORE;
targetPhrase->GetScoreBreakdown().Assign(&unknownWordPenaltyProducer, score);
targetPhrase->EvaluateInIsolation(sourceRhs);
Word *targetLhs = new Word(staticData.GetOutputDefaultNonTerminal());
targetPhrase->SetTargetLHS(targetLhs);
targetPhrase->SetAlignmentInfo(alignmentSS.str());
return targetPhrase;
}
} // T2S
} // Syntax
} // Moses
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