title: Javascript : Seems like typeof doesn't work
body: <p>I want to set a Value in a javascript object only when it is not set. My (test) function looks like:</p>
  
  <pre><code>var test = function(){
      this.value = {};
  
      this.setValue = function(seperator, newValue){
          console.log((this.value[seperator] === "undefined"));  //Why both times false?
          if(typeof(this.value[seperator] === "undefined")){
              this.value[seperator] = newValue;
          }else{
              //noop
          }
          console.log(this.value[seperator]);
      }
  }
  var blubb = new test();
  
  blubb .setValue("foo","bar");
  blubb .setValue("foo","notme");
  </code></pre>
  
  <p>in the js console it returns</p>
  
  <pre><code>false
  bar
  false
  notme
  </code></pre>
  
  <p>Can someone tell me why both time my test of "undefined" told me that is not defined?</p>
  
  <p>thanks in advance</p>