title: Ruby: get a list of extended modules?
body: <p>When you include modules in a class or other module you can call </p>
  
  <pre><code>@mymod.included_modules
  </code></pre>
  
  <p>to get a list of modules included.</p>
  
  <p>Is there an equivalent for listing the modules a module was extended by?</p>
  
  <pre><code>module Feature1
  end
  
  module Feature2
    extend Feature1
  end
  
  Feature2.extended_modules #=&gt; [Feature1]
  </code></pre>