title: D3JS blink link
body: <p>I am using d3js collapsible tree.
  <a href="https://bl.ocks.org/mbostock/4339083" rel="nofollow noreferrer">https://bl.ocks.org/mbostock/4339083</a></p>
  
  <p>How to make link blink(flash)? Can nodes also  be made to show/hide at regular interval? I hope it can be done without using setInterval.</p>
  
  <p>Thanks in advance</p>