1 files changed, 71 insertions, 49 deletions

diff --git a/rst_parser/arc_ff.cc b/rst_parser/arc_ff.cc
index f9effbda..10885716 100644
--- a/rst_parser/arc_ff.cc
+++ b/rst_parser/arc_ff.cc
@@ -6,59 +6,81 @@
 
 using namespace std;
 
-ArcFeatureFunction::~ArcFeatureFunction() {}
+struct ArcFFImpl {
+  ArcFFImpl() : kROOT("ROOT") {}
+  const string kROOT;
 
-void ArcFeatureFunction::PrepareForInput(const TaggedSentence&) {}
+  void PrepareForInput(const TaggedSentence& sentence) {
+    (void) sentence;
+  }
+
+  void EdgeFeatures(const TaggedSentence& sent,
+                    short h,
+                    short m,
+                    SparseVector<weight_t>* features) const {
+    const bool is_root = (h == -1);
+    const string& head_word = (is_root ? kROOT : TD::Convert(sent.words[h]));
+    const string& head_pos = (is_root ? kROOT : TD::Convert(sent.pos[h]));
+    const string& mod_word = TD::Convert(sent.words[m]);
+    const string& mod_pos = TD::Convert(sent.pos[m]);
+    const bool dir = m < h;
+    int v = m - h;
+    if (v < 0) {
+      v= -1 - int(log(-v) / log(2));
+    } else {
+      v= int(log(v) / log(2));
+    }
+    static map<int, int> lenmap;
+    int& lenfid = lenmap[v];
+    if (!lenfid) {
+      ostringstream os;
+      if (v < 0) os << "LenL" << -v; else os << "LenR" << v;
+      lenfid = FD::Convert(os.str());
+    }
+    features->set_value(lenfid, 1.0);
+    const string& lenstr = FD::Convert(lenfid);
+    if (!is_root) {
+      static int modl = FD::Convert("ModLeft");
+      static int modr = FD::Convert("ModRight");
+      if (dir) features->set_value(modl, 1);
+      else features->set_value(modr, 1);
+    }
+    if (is_root) {
+      ostringstream os;
+      os << "ROOT:" << mod_pos;
+      features->set_value(FD::Convert(os.str()), 1.0);
+      os << "_" << lenstr;
+      features->set_value(FD::Convert(os.str()), 1.0);
+    } else { // not root
+      ostringstream os;
+      os << "HM:" << head_pos << '_' << mod_pos;
+      features->set_value(FD::Convert(os.str()), 1.0);
+      os << '_' << dir;
+      features->set_value(FD::Convert(os.str()), 1.0);
+      os << '_' << lenstr;
+      features->set_value(FD::Convert(os.str()), 1.0);
+      ostringstream os2;
+      os2 << "LexHM:" << head_word << '_' << mod_word;
+      features->set_value(FD::Convert(os2.str()), 1.0);
+      os2 << '_' << dir;
+      features->set_value(FD::Convert(os2.str()), 1.0);
+      os2 << '_' << lenstr;
+      features->set_value(FD::Convert(os2.str()), 1.0);
+    }
+  }
+};
 
-DistancePenalty::DistancePenalty(const string&) : fidw_(FD::Convert("Distance")), fidr_(FD::Convert("RootDistance")) {}
+ArcFeatureFunctions::ArcFeatureFunctions() : pimpl(new ArcFFImpl) {}
+ArcFeatureFunctions::~ArcFeatureFunctions() { delete pimpl; }
+
+void ArcFeatureFunctions::PrepareForInput(const TaggedSentence& sentence) {
+  pimpl->PrepareForInput(sentence);
+}
 
-void DistancePenalty::EdgeFeaturesImpl(const TaggedSentence& sent,
+void ArcFeatureFunctions::EdgeFeatures(const TaggedSentence& sentence,
                                        short h,
                                        short m,
                                        SparseVector<weight_t>* features) const {
-  const bool dir = m < h;
-  const bool is_root = (h == -1);
-  int v = m - h;
-  if (v < 0) {
-    v= -1 - int(log(-v) / log(2));
-  } else {
-    v= int(log(v) / log(2));
-  }
-  static map<int, int> lenmap;
-  int& lenfid = lenmap[v];
-  if (!lenfid) {
-    ostringstream os;
-    if (v < 0) os << "LenL" << -v; else os << "LenR" << v;
-    lenfid = FD::Convert(os.str());
-  }
-  features->set_value(lenfid, 1.0);
-  const string& lenstr = FD::Convert(lenfid);
-  if (!is_root) {
-    static int modl = FD::Convert("ModLeft");
-    static int modr = FD::Convert("ModRight");
-    if (dir) features->set_value(modl, 1);
-    else features->set_value(modr, 1);
-  }
-  if (is_root) {
-    ostringstream os;
-    os << "ROOT:" << TD::Convert(sent.pos[m]);
-    features->set_value(FD::Convert(os.str()), 1.0);
-    os << "_" << lenstr;
-    features->set_value(FD::Convert(os.str()), 1.0);
-  } else { // not root
-    ostringstream os;
-    os << "HM:" << TD::Convert(sent.pos[h]) << '_' << TD::Convert(sent.pos[m]);
-    features->set_value(FD::Convert(os.str()), 1.0);
-    os << '_' << dir;
-    features->set_value(FD::Convert(os.str()), 1.0);
-    os << '_' << lenstr;
-    features->set_value(FD::Convert(os.str()), 1.0);
-    ostringstream os2;
-    os2 << "LexHM:" << TD::Convert(sent.words[h]) << '_' << TD::Convert(sent.words[m]);
-    features->set_value(FD::Convert(os2.str()), 1.0);
-    os2 << '_' << dir;
-    features->set_value(FD::Convert(os2.str()), 1.0);
-    os2 << '_' << lenstr;
-    features->set_value(FD::Convert(os2.str()), 1.0);
-  }
+  pimpl->EdgeFeatures(sentence, h, m, features);
 }
+