title: Map() is not defined in Google Chrome
body: <p>I've been searching for an answer but I'm only getting results regarding the Google maps API. I'm trying to use a map in JavaScript to map an integer to a string. Everything is working fine in Firefox but in chrome I get an error message in the console:</p>
  
  <blockquote>
    <p>Uncaught ReferenceError: Map is not defined</p>
  </blockquote>
  
  <p>Below is a piece of reference code:</p>
  
  <pre><code>var NameMap;
  var DistanceMap;
  
  function FillMaps(){
      NameMap = new Map();
      DistanceMap = new Map();
  
      NameMap.set(01, "Araba/Álava");
  }
  
  function CheckName(_field){
      var value = document.getElementsByName(_field.name).item(0).value;
      var location = value.charAt(0) + value.charAt(1);
      var result = NameMap.get(parseInt(location));
      if(result == undefined){
          result = "Unknown";
      }
      document.getElementById('loc').innerHTML = result;
  }
  </code></pre>