title: which nested data structure should I use for FluidFramework
body: <p>If I want to use nested data structure, which data structure is better choose.</p>
  <p>eg.</p>
  <p><a href="https://i.stack.imgur.com/qBo32.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qBo32.png" alt="enter image description here" /></a></p>
  <p>For eg1 case, It seems can not load children DDS data in '<strong>hasInitialized()</strong>'.</p>
  <p>For eg2, it seems a little complicated.</p>
  <p>Is anyone can show some example for this case?</p>