Firebase.update failed : first argument contains undefined in property
<p>I have a simple Firebase function that updates some data. However, the interpreter says that the first argument contains "undefined" in property 'users.tester1'. Can somebody help me please?</p>

<pre><code>var objify = function() {
  var rv = {};
    for (var i = 0; i &lt; arguments.length; ++i)
      rv[arguments[i]] = rv[arguments[i+1]];
    return rv;
}

    addUser("tester1", []);

var addUser = function(name, edges){
  if(!checkIfUsernameExists(name) &amp;&amp; !checkIfNodeNameExists(name) &amp;&amp; !checkIfEdgeNameExists(name)){
    var time = Firebase.ServerValue.TIMESTAMP;

    //HERE: I think the error is on this line 
    refs.users.update(objify(name, "filler"));

    refs.users.child(name).set({
      "id" : time,
      "edges" : "filler"
    });
    refs.users.child(name).child("edges").update({
      "to" : "filler",
      "from" : "filler"
    });

    addNode(new Node(name, time, name));

    for(var e in edges){
      refs.users.child(name).child("edges/to").update(objify(edges[e].name, true));
      addEdge(new Edge(edges[e].name, time, edges[e].to, edges[e].arrows));
      //TODO add a "from" edge so that you know who wants to eat you
    }
    refs.users.child(name).child("edges/to").set({"filler" : null});
  } else {
    alert("user/node/edge name taken.");
  }
};
</code></pre>