code: function(to, evt, indexMap) {
        var result,
          feedbackToInvoke = _.find(this.feedback, function(feedback) {
            var toToCheck = feedback.to;
            if (_.isArray(toToCheck)) {
              return _.contains(toToCheck, to);
            } else {
              return to === toToCheck;
            }
          }),
          feedbackCellField = to;
        if (feedbackToInvoke) {
          if (indexMap) {
            feedbackCellField = this.__substituteIndicesUsingMap(to, indexMap);
          }
          result = feedbackToInvoke.then.call(this, evt, indexMap);
          this.__processFeedbackThenResult(result, feedbackCellField);
        }
      }
docs: Invokes a feedback entry's "then" method
  @param to {String} the "to" field corresponding to the feedback entry to be invoked.
  @param [evt] {Event} the event to be passed to the "then" method
  @param [indexMap] {Object} a map from index variable name to index value. Needed for "to" fields with array notation.
  @method invokeFeedback