<svg-attr>
  <svg width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <defs>
      <g id="circle">
        <circle r="10"/>
      </g>
    </defs>
    <use ref='target' x="50" y="10" xlink:href={ href } />
  </svg>
  <script>
    this.href = '#circle'
  </script>
</svg-attr>