在jquery模板中获取父for循环的值

<script id="template" type="text/x-jquery-tmpl">
  {{each items}}
    <div class="parent">
      Parent Value: ${$value}
      {{each childItems}}
        <div class="child">
          Child Value: ${$value}
          Parent Value: ${$item.$parent.$value}
        </div>
      {{/each}}
    </div>
  {{/each}}
</script>

<div id="output"></div>

<script>
  var data = {
    items: [
      {
        value: "Parent 1",
        childItems: [
          { value: "Child 1-1" },
          { value: "Child 1-2" }
        ]
      },
      {
        value: "Parent 2",
        childItems: [
          { value: "Child 2-1" },
          { value: "Child 2-2" }
        ]
      }
    ]
  };

  var template = $("#template").html();
  var rendered = $.tmpl(template, data);
  $("#output").append(rendered);
</script>