title: Get non-static methods from a class instead of an instance
body: <p>I'm developing a JS library.</p>
  
  <p>Somewhere the user passes a <strong>class</strong> reference (not an instance!) to one of my factory objects. Now, i want to check that this class implements a certain interface.</p>
  
  <p>If i had an instance i could easily check that it contains the interface's methods, however, I have a class and no knowledge how to instantiate it. Is there still a way to check (at runtime) if the class implements the required methods?</p>
  
  <p>Currently, i force the user to pass an instance of the class, which is somewhat annoying since I only need the class.</p>