mockNext = function(err) {
      if (err) {
        return next(new Error('`next` (as in req,res,next) should never be called in an action function (but in action `' + actionIdentity + '`, it was!)  It was called with an error: ' + (_.isError(err) ? err.stack : util.inspect(err, {
          depth: null
        }) + '') + '  Please use a method like `res.serverError()` or `res.badRequest()` instead.'));
      }

      return next(new Error('`next` (as in req,res,next) should never be called in an action function (but in action `' + actionIdentity + '`, it was!)  It was called with no arguments.  Please use a method like `res.ok()` or `res.json()` instead.'));

    }
Bind a previously-loaded action to a URL.
(which should be a URL or redirectable path.)

@api private