title: Does std::regex support "(?i)" for case insensitivity?
body: <p>I am using Visual Studio 2010.  This...</p>
  
  <p><code>std::regex pattern("(?i).*a.*");</code></p>
  
  <p>...throws this...</p>
  
  <p><code>std::tr1::regex_error - regular expression error</code></p>
  
  <p>...and I can't find anything that says if <code>std::regex</code> supports the <code>(?i)</code> syntax for case insensitivity or not.</p>
  
  <p>Can anyone confirm/deny that <code>(?i)</code> is not supported as a prefix for case insensitivity by <code>std::regex</code>?</p>