title: C conditional operator ('?') with empty second parameter
body: <p>Typically the '?' operator is used in the following form:</p>
  
  <pre><code>A ? B : C
  </code></pre>
  
  <p>However in cases where B = A I have seen the following abbreviation</p>
  
  <pre><code>A ? : C
  </code></pre>
  
  <p>This surprisingly works. Is it better to leave the second parameter in (style wise), or is their a chance certain compilers won't be able to handle this?</p>