title: Use custom MD5 formula with ARRAYFORMULA
body: <p>I implemented an MD5 formula as mentioned here: <a href="https://stackoverflow.com/questions/7994410/hash-of-a-cell-text-in-google-spreadsheet?noredirect=1&amp;lq=1">Hash of a cell text in Google Spreadsheet</a>.</p>
  
  <pre><code>function MD5 (input) {
    var rawHash = Utilities.computeDigest(Utilities.DigestAlgorithm.MD5, input);
    Utilities.sleep(100)
    var txtHash = '';
    for (i = 0; i &lt; rawHash.length; i++) {
      var hashVal = rawHash[i];
      if (hashVal &lt; 0) {
        hashVal += 256;
      }
      if (hashVal.toString(16).length == 1) {
        txtHash += '0';
      }
      txtHash += hashVal.toString(16);
    }
    return txtHash;
  }
  </code></pre>
  
  <p>Now I want to run this with an <code>ARRAYFORMULA</code> but I can't get it working. I tried this:</p>
  
  <pre><code>=ARRAYFORMULA(({"FiBu MD5";IF(ISBLANK(AG2:AG),"",(MD5(O2:O)))}))
  </code></pre>
  
  <p>The error I'm getting is: </p>
  
  <blockquote>
    <p>"Cannot convert Array to (class)[]. (line 2)."</p>
  </blockquote>
  
  <p>Does anyone have an idea how to solve this?</p>