// REFLECT -- copy in PreludeCompiled

  private void writeFile(ISourceLocation sloc, IList V, boolean append, IEvaluatorContext ctx){

    sloc = ctx.getHeap().resolveSourceLocation(sloc);

   

    if (append) {

      // in case the file already has a encoding, we have to correctly append that.

      InputStream in = null;

      Charset detected = null;

      try {

    StringBuilder b = new StringBuilder(str.length() * 2);

   

    int sLength = str.length();

    for (int c = 0; c < sLength; c++) {

      if (sub != null) {

      }

      else {

        b.append(chr.getValue());

      }

    }

      }

     

      private String replaceEverythingBySpace(String input) {

        StringBuilder sb = new StringBuilder();

          if (ch != ' ' && ch != '\t') {

            sb.append(' ');

          }

          else {

            sb.appendCodePoint(ch);

      throw RuntimeExceptionFactory.permissionDenied(

          vf.string("getLog called before startLog"),

          e.getCurrentAST(), null);

    }

    Evaluator eval = (Evaluator) e;

    eval.revertToDefaultWriters();

    logger = null;

    return result;

  }

      String vname =  fromName + "_" + to.name + "[" + (from.layer + delta) + "]";

      if(debug)System.err.println("Creating virtual node " + vname + " between " + fromName + " and " + to.name);

      LayeredGraphNode virtual = new LayeredGraphNode(this, vname, hgap/2, vgap);

      IValueFactory vf = ValueFactoryFactory.getValueFactory();

      nodes.add(virtual);

     

      registerNodeId(vname, virtual);

     

      LinkedList<LayeredGraphNode> vlayer = layers.get(from.layer+delta);

      virtual.layer = from.layer + delta;

      virtual.pos = vlayer.size();

      virtual.in.add(from);

      virtual.out.add(to);

      from.out.set(from.out.indexOf(to), virtual);

      to.in.set(to.in.indexOf(from), virtual);

      vlayer.add(virtual);

      LayeredGraphEdge old = null;

      for(LayeredGraphEdge e : edges){

        if(debug)System.err.println("Consider edge " + e.getFrom().name + " -> " + e.getTo().name);

        if(e.getFrom() == from && e.getTo() == to){

          old = e;

          if(from == orgFrom){

            orgEdgeLabel = e.getLabel();

          }

          if(debug)System.err.println("Removing old edge " + from.name + " -> " + to.name);

          break;

        }

      }

      //if(old == null)

      //  throw RuntimeExceptionFactory.figureException("Internal error in insertVirtualNode", vfVname, fpa.getRascalContext().getCurrentAST(), fpa.getRascalContext().getStackTrace());

      if(old != null){

        if(old.isReversed()){

          LayeredGraphEdge e1 = new LayeredGraphEdge(this, fpa, old.prop, vfGname, vfVname, old.fromArrow, old.toArrow);

          LayeredGraphEdge e2 = new LayeredGraphEdge(this, fpa, old.prop, vfVname, vfOname, old.fromArrow, old.toArrow);

          e2.label = orgEdgeLabel;