code: function isA(publicAPI, model = {}, name = null) {
    if (!model.isA) {
      model.isA = [];
    }
  
    if (name) {
      model.isA.push(name);
    }
  
    if (!publicAPI.isA) {
      publicAPI.isA = (className) => model.isA.indexOf(className) !== -1;
    }
  }
docs: ---------------------------------------------------------------------------- Add isA function and register your class name ----------------------------------------------------------------------------