title: dynamic script loading synchronization
body: <p>I have a script that knows to load dynamiclly scripts that contains javascript classes.
  i'm loading the class script using the following code:</p>
  
  <pre><code>var head = document.getElementsByTagName("head")[0];
  var script = document.createElement("script");
  script.type = "text/javascript";
  script.src = "myscript.js";
  head.appendChild(script);
  </code></pre>
  
  <p>i'm then trying to create the new class using eval:</p>
  
  <pre><code>var classObj = eval(" new MyClass()" );
  </code></pre>
  
  <p>the problem is that the code of the eval is being executed bofre the script has been loaded into memory and i get an error that the <code>MyClass is undefined.</code> </p>
  
  <p>Is there a way to synch these events? i need to make sure the script is fully being loaded into memory before i can start allocating classes from it.</p>