title: Is the use of <> as a not-equal operator documented somewhere?
body: <p>looking at existing APEX code I've seen quite a few places where not equal is tested using "&lt;>" instead of "!=". 
  I can't find an official documentation where this behaviour is described. Does anyone know if this has any potential side effects? Should that be changed to use != wherever possible?</p>
  
  <p>I'd be thankful for any hints / references.</p>