title: How to create set across JSON (AngularJS)
body: <p>I have a JSON like this: </p>
  
  <pre><code>{
      "list": [{
              "name": "1",
              "type": ["A", "B"],
          },
          {
              "name": "2",
              "type": ["A", "D", "C"],
          },
          {
              "name": "3",
              "type": ["D", "E"],
          }
      ]
  }
  </code></pre>
  
  <p>I'd like output a set of types (meaning, unique type values across <code>list</code>), like so: </p>
  
  <pre><code>Types: A, B, C, D, E
  </code></pre>
  
  <p>I'm trying to do something like </p>
  
  <pre><code>&lt;div ng-repeat="element.type in list | unique='type'"&gt;
    {{element.type}}
  &lt;/div&gt;
  </code></pre>
  
  <p>but can't get it quite right. What's the right way to do this? </p>