code: function() {
        var t = this,
            newValue = t.eval_control(t.key, t.depth);
  
        // Set the new value if it has changed from the current value
        if (!_.isEqual(newValue, t.get('value'))) {
          t.set({value: newValue});
        }
      }
docs: Poll for changes in the evaluation
  
  @method poll