code: function component(container, data, context) {
      const selection = container.nodeName ? select(container) : container;
      const instances = selection
        .selectAll(mine)
        .data(dataArray(data, context), key);
      instances
        .exit()
        .each(destroyInstance);
      return instances
        .enter().append(tagName)
        .attr('class', className)
        .each(createInstance)
        .merge(instances)
        .each(renderInstance);
    }
docs: The returned component instance.