title: How to verify containing values in hash tables without loop?
body: <p>How to verify containing values in hash tables without loop in javascript?
  For example:</p>
  
  <pre><code>var a = new Object(); // or just []
  a[0] = 0
  a['one'] = 1;
  a['two'] = 2;
  a['three'] = 3;
  </code></pre>