code: function (parentComponent, nextElement, container, callback) {
      !(parentComponent != null && ReactInstanceMap.has(parentComponent)) ? "development" !== 'production' ? invariant(false, 'parentComponent must be a valid React Component') : _prodInvariant('38') : void 0;
      return ReactMount._renderSubtreeIntoContainer(parentComponent, nextElement, container, callback);
    }
docs: Renders a React component into the DOM in the supplied `container`.
  
  If the React component was previously rendered into `container`, this will
  perform an update on it and only mutate the DOM as necessary to reflect the
  latest React component.
  
  @param {ReactComponent} parentComponent The conceptual parent of this render tree.
  @param {ReactElement} nextElement Component element to render.
  @param {DOMElement} container DOM element to render into.
  @param {?function} callback function triggered on completion
  @return {ReactComponent} Component instance rendered in `container`.