private static void parameters(Tree.TypeParameterList tpl, StyledString label) {
   if (tpl != null && !tpl.getTypeParameterDeclarations().isEmpty()) {
     label.append("<");
     int len = tpl.getTypeParameterDeclarations().size(), i = 0;
     for (Tree.TypeParameterDeclaration p : tpl.getTypeParameterDeclarations()) {
       label.append(name(p.getIdentifier()), TYPE_STYLER);
       if (++i < len) label.append(", ");
     }
     label.append(">");
   }
 }