title: Force antlr3 to immediately exit when a rule fails
body: <p>I've got a rule like this:</p>
  
  <pre><code>declaration returns [RuntimeObject obj]: 
      DECLARE label value { $obj = new RuntimeObject($label.text, $value.text); };
  </code></pre>
  
  <p>Unfortunately, it throws an exception in the <code>RuntimeObject</code> constructor because <code>$label.text</code> is null. Examining the debug output and some other things reveals that the match against "label" actually failed, but the Antlr runtime "helpfully" continues with the match for the purpose of giving a more helpful error message (<a href="http://www.antlr.org/blog/antlr3/error.handling.tml" rel="nofollow noreferrer">http://www.antlr.org/blog/antlr3/error.handling.tml</a>).</p>
  
  <p>Okay, I can see how this would be useful for some situations, but how can I tell Antlr to stop doing that? The <code>defaultErrorHandler=false</code> option from v2 seems to be gone.</p>