title: Difference between calling method_missing in Ruby with and without parentheses
body: <p>Is there any possibility to establish in method_missing declaration in Ruby whether a given missing_method was called (without any arguments) using parentheses notation, ie:</p>
  
  <pre><code>foo.non_existing_method()
  </code></pre>
  
  <p>or using parentheses-less notation:</p>
  
  <pre><code>foo.non_existing_method
  </code></pre>
  
  <p>?</p>
  
  <p>I need this to solve my very specific testing problem.</p>