protected BinaryRule projectBinaryRule(BinaryRule br) {
   BinaryRule br2 = new BinaryRule();
   br2.parent = projection[br.parent];
   br2.leftChild = projection[br.leftChild];
   br2.rightChild = projection[br.rightChild];
   br2.score = br.score;
   return br2;
 }
 protected Rule specifyRule(Rule rule, List history, int childDepth) {
   Rule r;
   String topHistoryStr = historyToString(history.subList(1, history.size()));
   String bottomHistoryStr = historyToString(history.subList(0, childDepth));
   if (rule instanceof UnaryRule) {
     UnaryRule ur = new UnaryRule();
     UnaryRule urule = (UnaryRule) rule;
     ur.parent = stateNumberer.number(stateNumberer.object(urule.parent) + topHistoryStr);
     if (isSynthetic(urule.child)) {
       ur.child = stateNumberer.number(stateNumberer.object(urule.child) + topHistoryStr);
     } else if (isTag(urule.child)) {
       ur.child = urule.child;
     } else {
       ur.child = stateNumberer.number(stateNumberer.object(urule.child) + bottomHistoryStr);
     }
     r = ur;
   } else {
     BinaryRule br = new BinaryRule();
     BinaryRule brule = (BinaryRule) rule;
     br.parent = stateNumberer.number(stateNumberer.object(brule.parent) + topHistoryStr);
     if (isSynthetic(brule.leftChild)) {
       br.leftChild = stateNumberer.number(stateNumberer.object(brule.leftChild) + topHistoryStr);
     } else if (isTag(brule.leftChild)) {
       br.leftChild = brule.leftChild;
     } else {
       br.leftChild =
           stateNumberer.number(stateNumberer.object(brule.leftChild) + bottomHistoryStr);
     }
     if (isSynthetic(brule.rightChild)) {
       br.rightChild =
           stateNumberer.number(stateNumberer.object(brule.rightChild) + topHistoryStr);
     } else if (isTag(brule.rightChild)) {
       br.rightChild = brule.rightChild;
     } else {
       br.rightChild =
           stateNumberer.number(stateNumberer.object(brule.rightChild) + bottomHistoryStr);
     }
     r = br;
   }
   return r;
 }
 protected Rule ltToRule(Tree lt) {
   if (lt.children().length == 1) {
     UnaryRule ur = new UnaryRule();
     ur.parent = stateNumberer.number(lt.label().value());
     ur.child = stateNumberer.number(lt.children()[0].label().value());
     return ur;
   } else {
     BinaryRule br = new BinaryRule();
     br.parent = stateNumberer.number(lt.label().value());
     br.leftChild = stateNumberer.number(lt.children()[0].label().value());
     br.rightChild = stateNumberer.number(lt.children()[1].label().value());
     return br;
   }
 }