Computed PropertyCheck

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  prop1: true,
  
  samp: Ember.computed('prop1', {
  	get() {
      return 1;
    },
    set(key, value) {
    	return value;
    }
  }),
  actions: {
    changeProp() {
    	this.set('prop1', false);
    },
    
    changeSamp() {
    	this.set('samp', 2);
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{samp}}
<button {{action "changeSamp"}}>Change SAMP</button>
<button {{action "changeProp"}}>Change Prop</button>
<br>
<br>

twiddle.json

{
  "version": "0.11.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.11.0",
    "ember-data": "2.11.0",
    "ember-template-compiler": "2.11.0",
    "ember-testing": "2.11.0"
  },
  "addons": {}
}