New Twiddle

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  attr: {
        "type":{
          "label":"Type",
          "fieldType":"esriFieldTypeString"
        },
        "date":{
          "label":"Type",
          "fieldType":"esriFieldTypeDate"
        },
        "address":{
          "label":"Address",
          "fieldType":"esriFieldTypeString"
        }
      },
  mappings: {
        "type":{
          "field":"CRIMTYP"
        },
        "date":{
          "field":"OCCURED_ON"
        },
        "address":{
          "field":"ADDR"
        }
      },
  attrJson:Ember.computed('attr',function(){
  	return JSON.stringify( this.get('attr'), null, 4);
  }),
  mappingsJson:Ember.computed('mappings',function(){
  	return JSON.stringify( this.get('mappings'), null, 4);
  }),
  merged: Ember.computed('attr',function(){
    return $.extend(true, this.get('attr'), this.get('mappings') );
  }),
  mergedJson: Ember.computed('merged',function(){
    return JSON.stringify( this.get('merged'), null, 4);
  })
    
});

templates.application.hbs

<h1>Object Merging Experiments</h1>
<h2>Attributes</h2>
  <code>
    <pre style="width:400px;height:250px;">{{attrJson}}</pre>
  </code>
<hr>
<h2>Mappings</h2>
  <code>
    <pre style="width:400px;height:250px;">{{mappingsJson}}</pre>
  </code>
<hr>
<br>
<h2>Merged Json</h2>
  <code>
    <pre style="width:400px;height:250px;">{{mergedJson}}</pre>
  </code>
<hr>
<h2>Properties on Merged Object</h2>
{{#each-in merged as |key child|}}
   <p>
   {{key}}<br>
   {{child.label}}:{{child.fieldType}}:{{child.field}}
   </p>
{{/each-in}}
<br>
<br>

twiddle.json

{
  "version": "0.10.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.6.0",
    "ember-data": "2.6.1",
    "ember-template-compiler": "2.6.0"
  },
  "addons": {}
}