code: function(nodeList, unregistered, parent) {
                  // If a unregistered callback has been provided assign it to the nodeList
                  // as a property to be called when the nodeList is unregistred.
                  nodeList.unregistered = unregistered;
                  nodeList.parentList = parent;
  
                  if (parent === true) {
                      // this is the "top" parent in stache
                      nodeList.replacements = [];
                  } else if (parent) {
                      // TOOD: remove
                      parent.replacements.push(nodeList);
                      nodeList.replacements = [];
                  } else {
                      nodeLists.nestList(nodeList);
                  }
  
  
                  return nodeList;
              }
docs: ## nodeLists.register Registers a nodeList and returns the nodeList passed to register