title: Is the C99 preprocessor Turing complete?
body: <p>After discovering the <a href="http://www.boost.org/doc/libs/1_41_0/libs/preprocessor/doc/index.html" rel="noreferrer">Boost preprocessor's capabilities</a> I found myself wondering: Is the C99 preprocessor Turing complete?</p>
  
  <p>If not, what does it lack to not qualify?</p>