Computed Property

controllers.application.js

import Ember from 'ember';

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

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  bar: 'baz',
  foo: Ember.computed('bar', function () {
    return this.get('bar');
  }),
  model: function () {
    return this.get('foo');
  },
  actions: {
    update: function () {
      this.set('bar', 'updated');
      console.log(this.get('foo'));
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
Model: {{model}}
<br>
<br>
<a {{action 'update'}}>Update</a>

twiddle.json

{
  "version": "0.9.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.6.0",
    "ember-data": "2.6.0",
    "ember-template-compiler": "2.6.0"
  }
}