code: function _reportNode(node) {
    if (node.id) {
      return "id: " + node.id;
    } else if (node.label) {
      return "label: " + node.label;
    } else if (node.value) {
      return "value: " + node.value;
    } else if (node.hasAttributes()) {
      var attrs = "node attributes: ";
      for (var i = node.attributes.length - 1; i >= 0; i--) {
        attrs += node.attributes[i].name + "->" + node.attributes[i].value + ";";
      }
      return attrs;
    } else {
      return "anonymous node";
    }
  }
docs: Tries to return a useful string identificator of the given node
  
  @param {node} node
  @returns Identificator of the node
  @type {String}