The `err, results` params form the signature of a continuation-passing style "errback":

    function(err, results) {
      if (err) // …
    }

It is assumed that this function will be executed asynchronously, and thus it's not possible for anything to consume the return value anyway.

If you want to control the return value, simply return on a new line or use the void operator:

   return void handleError(err)