New Twiddle

controllers.application.js

import Ember from 'ember';
import RSVP from 'rsvp';
import { computed } from '@ember/object';

const MyClass = Ember.Object.extend({
  awaitLoadedData: computed.readOnly('_deferDataLoad.promise'),
  _onDataLoaded() {
    this.get('_deferDataLoad').resolve(this);
  },
  _deferDataLoad: computed(() => RSVP.defer()),
});

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  bob: computed(function() {
    let myObject = MyClass.create();
    myObject.get('awaitLoadedData')
    	.then(() => {
        console.log('it is loaded');
	    });
    myObject._onDataLoaded({});
    console.log(myObject);
  }),
});

templates.application.hbs

{{bob}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.8",
    "ember-template-compiler": "3.4.8",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}