title: Loop through array of objects and return object keys
body: <p>My code is as follows : </p>
  
  <pre><code>let filters = [ 
      {name: "MAKE", values: 
      [
        {
          Volkswagen: {active: true, make: "Volkswagen"},
          Skoda: {active: true, make: "Skoda"}
        }
      ]
      }
  ]
  
  function getFilterValues(){
    return filters.filter(f =&gt; {
      if(f.name == "MAKE"){
        return f.values.filter(i =&gt; {
          Object.keys(i).map(key =&gt; {
            return key;
          });
        });
      }
    });
  }
  
  var div = document.getElementById('output');
  div.innerHTML = getFilterValues();
  </code></pre>
  
  <p>I want to loop through filters to get the object keys. </p>
  
  <p>Thus the result that I want is, in this case <em>Volkswagen, Skoda</em>. But my function getFilterValues doesn't return what I want.</p>
  
  <p>Here is <a href="https://jsfiddle.net/o93Lm0rc/100/" rel="nofollow">jsfiddle</a>.</p>
  
  <p>Any advice?</p>