CP access

controllers.application.js

import Ember from 'ember';
import EmberObject, { computed } from '@ember/object';
import { dasherize } from '@ember/string';

let Band = EmberObject.extend({
	name: '',
	language: '',
	slug: computed('name', function() {
		console.log('Recomputing slug');
		return dasherize(this.name);
	}),
	site: computed('slug', 'language', function() {
		console.log('Recomputing site');
		return `https://bands.com/${this.slug}.${this.language}`;
	})
});

let band = Band.create({ name: 'Mookie Blaylock', language: 'jsp' });
console.log(1, band.site);
console.log(2, band.site);
band.set('name', 'Pearl Jam');
console.log(3, band.site);
band.set('language', 'php');
console.log(4, band.site);

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

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": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}