title: javascript object properties as parameters
body: <p>If in javascript object properties are passed by reference why  this doesnt work:</p>
  
  <pre><code>var myObj={a:1}
  
  function myFun(x){
  x=2;
  }
  
  myFun(myObj.a);
  
  // value myObj.a is still 1
  </code></pre>
  
  <p>but on the other hand if you do this:</p>
  
  <pre><code>var myObj={a:1}
  
  function myFun(x){
  x.a=2;
  }
  
  myFun(myObj);
  
  // this works myObj.a is 2
  </code></pre>