1 files changed, 66 insertions, 0 deletions
diff --git a/decoder/scfg_translator.cc b/decoder/scfg_translator.cc
new file mode 100644
index 00000000..03602c6b
--- /dev/null
+++ b/decoder/scfg_translator.cc
@@ -0,0 +1,66 @@
+#include "translator.h"
+
+#include <vector>
+
+#include "hg.h"
+#include "grammar.h"
+#include "bottom_up_parser.h"
+#include "sentence_metadata.h"
+
+using namespace std;
+
+Translator::~Translator() {}
+
+struct SCFGTranslatorImpl {
+  SCFGTranslatorImpl(const boost::program_options::variables_map& conf) :
+      max_span_limit(conf["scfg_max_span_limit"].as<int>()),
+      add_pass_through_rules(conf.count("add_pass_through_rules")),
+      goal(conf["goal"].as<string>()),
+      default_nt(conf["scfg_default_nt"].as<string>()) {
+    vector<string> gfiles = conf["grammar"].as<vector<string> >();
+    for (int i = 0; i < gfiles.size(); ++i) {
+      cerr << "Reading SCFG grammar from " << gfiles[i] << endl;
+      TextGrammar* g = new TextGrammar(gfiles[i]);
+      g->SetMaxSpan(max_span_limit);
+      grammars.push_back(GrammarPtr(g));
+    }
+    if (!conf.count("scfg_no_hiero_glue_grammar"))
+      grammars.push_back(GrammarPtr(new GlueGrammar(goal, default_nt)));
+    if (conf.count("scfg_extra_glue_grammar"))
+      grammars.push_back(GrammarPtr(new GlueGrammar(conf["scfg_extra_glue_grammar"].as<string>())));
+  }
+
+  const int max_span_limit;
+  const bool add_pass_through_rules;
+  const string goal;
+  const string default_nt;
+  vector<GrammarPtr> grammars;
+
+  bool Translate(const string& input,
+                 SentenceMetadata* smeta,
+                 const vector<double>& weights,
+                 Hypergraph* forest) {
+    vector<GrammarPtr> glist = grammars;
+    Lattice lattice;
+    LatticeTools::ConvertTextOrPLF(input, &lattice);
+    smeta->SetSourceLength(lattice.size());
+    if (add_pass_through_rules)
+      glist.push_back(GrammarPtr(new PassThroughGrammar(lattice, default_nt)));
+    ExhaustiveBottomUpParser parser(goal, glist);
+    if (!parser.Parse(lattice, forest))
+      return false;
+    forest->Reweight(weights);
+    return true;
+  }
+};
+
+SCFGTranslator::SCFGTranslator(const boost::program_options::variables_map& conf) :
+  pimpl_(new SCFGTranslatorImpl(conf)) {}
+
+bool SCFGTranslator::Translate(const string& input,
+                               SentenceMetadata* smeta,
+                               const vector<double>& weights,
+                               Hypergraph* minus_lm_forest) {
+  return pimpl_->Translate(input, smeta, weights, minus_lm_forest);
+}
+