title: Circular dependencies in ES6/7
body: <p>I was surprised to find that in Babel, I could have two modules <code>import</code> each other without any issues. I have found a few places that refer to this as a known and expected behaviour in Babel. I know that this is widely considered an anti-pattern by a lot of (I'm guessing most) people, but please ignore that for this question:</p>
  
  <p>Does anyone know if this is (or will be) correct behaviour in ES6/7? </p>
  
  <p>The closest thing I can find to an official answer (and technical explanation) is <a href="http://www.2ality.com/2014/09/es6-modules-final.html#comment-2855933496" rel="noreferrer">this comment on 2ality.com</a></p>