title: "Uncaught TypeError: undefined is not a function" in my Google Chrome JavaScript console
body: <p>So I understand the above error means my browser is not recognizing a function I'm attempting to call. My question is why this is happening in my particular instance. I'll post the relevant code and maybe you guys can help me. </p>
  
  <p>I have a function </p>
  
  <pre><code>function homepage_screensaver()
  {
      // ... bunch of lines here .... 
      var circwrapper = new Array(mycirc, theta);
      document.setInterval(move_obj(circwrapper, papwidth, papheight), 100);
  }
  </code></pre>
  
  <p>which, as you can see, calls another function that I'm building right now: </p>
  
  <pre><code>function move_obj(obwrap, bckwid, bckht)
  {
       var c = obwrap[1]; 
       var t = obwrap[2]; 
       var bb = c.getBBox(); 
       // ... bunch of lines here ...      
  }
  </code></pre>
  
  <p>The error I'm getting is on the <code>var bb = c.getBBox();</code> line.</p>
  
  <p>I have a hunch. I think the problem has to do with me trying to wrap an object in an array and then unwrap it and call a function on it. Maybe the browser can't find the object's member function because of the fact that it has no idea what type of object it is in the first place.</p>
  
  <p>(I know the fact that I created a wrapper class is functionally useless, but it is for my own readability.)</p>
  
  <p>Anyways, what's the solution here?</p>