Find item with certain attribute with a certain value
<p>I'm trying to see if a list item with a certain attribute value does not exist. This code will help me find items with a certain attribute, but how do I modify it to check if there isn't a list item with that attribute set to a certain value? For example, if item with someAttributeName = exist does not exist, then...</p>

<pre><code>$(parentElement).find('*[someAttributeName]').each(function(index){
  doSomething(this);  });
</code></pre>
