title: Why Groovy constants can be incremented?
body: <p>In Groovy Console , <code>++(++(++(++1++)++)++)++</code> evaluates to <code>5</code> !<br>
  <strong>Why</strong> ?<br>
  I would expect an error that <strong>literal constants can not be incremented</strong> !</p>
  
  <p>Pre-Increment gives the next Integer, while Post-Increment gives the same Integer, but I would expect both to throw errors when used with literal constants.</p>
  
  <p>[[ I am running this on Windows 10 with Groovy 2.4.10 with Java 1.8.0_101 ]]</p>