code: function(com) {
              var root_nodes = this.root_nodes;
              if (typeof com === 'string') {
                  if (com in processor) {
                      var object = processor[com];
                      if (typeof object === 'object' && '__type' in object) {
                          delete processor[name];
                          var index = root_nodes.indexOf(object);
                          if (index >= 0)
                              root_nodes.splice(index, 1);
                      }
                  }
              } else {
                  var index = root_nodes.indexOf(com),
                      name = com.name;
                  if (index >= 0)
                      root_nodes.splice(index, 1);
                  if (processor[name] === com)
                      delete processor[name];
              }
              return this;
          }
docs: Remove the specified root node.
  
  @param {object|string} com Node object to be removed or root node name.
  @returns Returns this.