title: Do html5 data attributes need a value?
body: <p>I am wondering if html data attributes actually need a value to be applied?</p>
  
  <p>I wonder this because often all we want to know is if the attribute is actually set to act as a flag. (sure we could use a class for this; but realistically unless you are going to style these items differently then the flags are more data than a semantic item).</p>
  
  <p>A perfect example of this is if we want a link to scroll to it's target instead of jumping our jQuery code might look like:</p>
  
  <pre><code>$(document).on('click', '[data-scroll-link'], function(){/**do scroll**/});
  </code></pre>
  
  <p>I know in google chrome it is sufficient for the anchor to appear as </p>
  
  <pre><code>&lt;a href="#bottom" data-scroll-link&gt;Scroll to bottom&lt;/a&gt;
  </code></pre>
  
  <p>But will that work everywhere? and is it even valid HTML5 (I believe it is due to the autofocus, autoplay etc attributes). or do we need:</p>
  
  <pre><code>&lt;a href="#bottom" data-scroll-link="true"&gt;Scroll to bottom&lt;/a&gt;
  </code></pre>